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Tuesday, Septemb er 3
`First Galaxies' session
09:40-10:10 Richard Ellis Email: rse@astro.caltech.edu Title: Observations of Star-Forming Galaxies in the Reionization Era Abstract: Deep surveys with the Hubble Space Telescope have provided the primary evidence that star-forming galaxies were present in the first billion years of cosmic history. Sometime during this early perio d the intergalactic medium transitioned from a neutral gas to one that is fully ionized. How and when did this `cosmic reionization' o ccur and were star-forming galaxies primarily responsible? To address these questions requires the lo cation and study of galaxies in the heart of the reionization era, corresponding to redshifts 6-12. I will summarize recent progress in charting this important frontier of cosmic history from recent Hubble and Spitzer campaigns together with Keck infrared spectroscopy. 10:10-10:25 Ross McLure Email: rjm@ro e.ac.uk Title: The Hubble Ultra Deep Field 2012: galaxy evolution at z=7-10 Abstract: Studying the nature of the first generation of galaxies to form in the Universe is central to efforts to understand the earliest phases of galaxy evolution and the physical pro cesses driving cosmic reionization. Over the last decade this sub ject area has made rapid progress, thanks largely to successively deeper imaging in the optical and near-IR with the Hubble Space Telescope (HST). This talk will fo cus on the latest ultra-deep HST imaging campaign (HUDF12), an Edinburgh/Caltech pro ject which has recently delivered the deepest ever near-IR imaging of the distant Universe. The primary science goals of the pro ject were to provide the first robust sample of z>9 galaxies, to constrain the faint-end of the galaxy luminosity function at z=7 and z=8 and to study the spectral properties of 0.1L* galaxies at z=7. This talk will provide an overview of the first results from HUDF12, presenting new constraints on the luminosity functions, UV spectral slopes and star-formation densities of galaxies at z=7-8, before discussing the resulting implications for cosmic reionization. 10:25-10:40 Rychard Bouwens Email: bouwens@strw.leidenuniv.nl Title: Probing the Dawn of Galaxies at z7-12 Abstract: The WFC3/IR camera on HST has completely revolutionized the study of galaxies in the reionization epo ch, as it has pushed the observational frontier out to z9-12, only 450 Myr from the Big Bang. More than 400 candidates z7-11 galaxies are known, and now more than 12 galaxy candidates have been discovered at z9-11, as a result of the very deep observations from the field (HUDF09, CANDELS, HUDF12) and clusters (CLASH). Using observations from cluster programs, the HUDF, and CANDELS South, we find evidence that the cosmic star-formation rate density in galaxies with SFR>0.7Msol/yr increases by more than an order of magnitude in only 170 Myr from z10 to z8, pointing towards rapid growth in the galaxy population at early times. Current observations provide even stronger evidence than was available in 2010 for a consistent steepening in the faint-end slope alpha, from alpha -1.7 at z4 to -2.0 at z7-8. Finally, taking advantage of the combined power of new ACS + WFC3/IR + IRAC observations and gravitational lensing from clusters ­ we have been 1


conducting a thorough study of the physical properties, using the greater sample size and higher S/N to determine the typical UV-continuum slopes and sSFRs of individual galaxies at high redshift, to gain more insight into how galaxies build up in the early universe. In particular, our recent results on clusters provide much more direct evidence for high sSFRs in z7 galaxies than has previously been available. In this presentation, I summarize recent results from our group involving both lensing cluster (CLASH) and deep field (CANDELS/HUDF) observations. 10:40-10:55 George Becker Email: gdb@ast.cam.ac.uk Title: Galaxy Evolution in the Reionization Era Probed Using the UV Background Abstract: Determining when and how the first galaxies reionized hydrogen in the intergalactic medium would provide unique insights into the earliest stages of galaxy formation. One particular mystery, driven in part by recent observations of galaxies out to z8-10, is how the first galaxies could emit enough ionizing photons to complete reionization by z=6 unless the contribution from faint sources, the stellar populations and/or the escape fraction of ionizing photons are substantially different than for galaxies at lower later times. One approach to resolving this tension is to determine how efficiently galaxies ionize the IGM in the post-reionization era by studying the ionizing ultraviolet background (UVB). I will present new measurements of the UVB over 2 < z < 5 derived from recent measurements of the temperature and opacity of the intergalactic medium. Combined with measurements of galaxy luminosity functions over the same redshift interval, these results indicate that (1) the ionizing emissivity of highredshift galaxies is indeed sufficient to explain reionization at z > 6, and (2) the combined evolution in galaxy properties that enables reionization to o ccur is one that continues to substantially lower redshifts. 11:25-11:55 Jonathan Pritchard Invited talk 11:55-12:10 Renske Smit Email: rsmit@strw.leidenuniv.nl Title: Quantifying the Evolution of the Specific Star Formation Rate out to z7 using Gravitationally Lensed Galaxies from CLASH Abstract: By using strong lensing clusters as cosmic telescopes we can probe deep enough to study the build-up of galaxies out to very high redshifts. An important tracer of the efficiency of galaxy build-up with time is the global specific Star Formation Rate (sSFR), or the amount of star formation per unit mass. In recent years it has become apparent that a discrepancy exists in the evolution of the sSFR between simulations and observations. Specifically, at redshift z3-7 both semi-analytic mo dels as well as hydro dynamical simulations predict a strong rise in sSFR with redshift while most observations show the well-known specific star formation rate plateau. A potential problem in the measurement of galaxy masses at redshift z>4 is the contamination of strong nebular emission lines in the 3.6 and 4.5 mum Spitzer/IRAC bands that probe the rest-frame optical stellar continuum. To more accurately characterize the masses and other properties of high-redshift galaxies, high signal-to-noise IRAC imaging in combination with go o d redshift determinations are required. We select highly-magnified candidates identified behind lensing clusters from the CLASH program in a narrow redshift range z6.67.0 with mUV<26 mag. In this redshift interval the strongest emission lines are isolated to only one IRAC filter ([3.6]), while the adjacent filter ([4.5]) is free of emission lines. Not only do we place empirical con2


straints on the nebular emission line contamination, but we find evidence for a rapidly evolving sSFR for galaxies in the early universe. 12:10-12:25 Martin Haehnelt Email: haehnelt@ast.cam.ac.uk Title: Early growth of supermassive black holes Abstract: Supermassive black holes with masses of several billion solar masses are already in place at z6-7. I will discuss mo dels and numerical simulations of the early growth of these supermassive black holes and their environment with an emphasis 1. On the role of the formation of massive seed black holes by direct collapse in DM halo es with virial temperatures above the atomic co oling threshold 2. And the implications for the need (or not) for super-Eddington accretion rates 12:25-12:40 Jun Toshikawa Email: jun.toshikawa@nao.ac.jp Title: Search for protoclusters at z6 Abstract: I will present results of our systematic search for galaxy proto clusters at z6. Proto clusters provide a great deal of information of early stage of cluster formation for large-scale structure and environmental effects on galaxy evolution. We have discovered a proto cluster at z6, taking advantages of the unique wide-field imaging capability of Subaru telescope. It should be noted that this discovery was achieved in a "random field"; that is, QSOs or radio galaxies were not used as proto cluster probes. The overdense region covers 6' x 6' (14Mpc x 14Mpc in comoving units at z=6) and includes 30 i-dropout galaxies. Follow-up spectroscopy revealed that at least eight are clustering in a narrow redshift range, corresponding to a 7 sigma significance. The velo city dispersion was found to be much higher than the prediction of LCDM mo del, and this might be attributed to its unique three-dimensional distribution. Following the discovery, we extended the search to wider CFHTLS Deep Fields, and two overdensity regions of i-dropout galaxies have been found. Follow-up spectroscopy were carried out, which revealed that at least two i-dropout galaxies of each field are closely clustering in redshift space. We will discuss possible different properties of proto cluster galaxies from field galaxies at these first sites of galaxy cluster formation. 12:40-12:55 Pratika Dayal Email: prd@ro e.ac.uk Title: The earliest galaxies: chaotic and dusty Abstract: Over the past few years, instruments such as the Hubble Space Telescope have provided tantalising glimpses of a time when the earliest galaxies were just assembling in an infant Universe. In this talk, I will use theoretical mo dels to show how these galaxies assemble in mass and build up their luminosity, and quantify the effects of their chaotic assembly on observables such as the ultraviolet luminosity functions. Using the latest cosmological simulations, I will also show how these galaxies can be used as excellent probes of the physical properties of early galaxy populations, and their redshift evolution. I will end by showing that a substantial number of these galaxies are expected to be quite

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dusty and rich in CO, and should be detectable with state-of-the-art instruments such as ALMA.

`Galaxy Assembly and Star-formation History' session
14:30-15:00 Jim Dunlop Invited talk 15:00-15:15 Stephen Eales Email: sae@astro.cf.ac.uk Title: Following the energy - an investigation of galaxy evolution using the Herschel ATLAS and other Herschel Surveys Abstract: I will use the results of the Herschel ATLAS and HERMES to show how the bolometric luminosity function of the universe evolves from z=0 to z=4. The evolution of the luminosity function can be seen even at z=0.1 and continues to the highest redshifts seen in the H-ATLAS. I investigate the cause of this evolution using measurements of the environmental density and star-formation rates of the galaxies at z < 0.6. I show that the division of galaxies into blue star-forming galaxies and red passive galaxies is seriously incomplete, and that approximately 1/3 of the H-ATLAS are red galaxies that are still forming stars. I will interpret these results using two alternatives mo dels: a mo del of an evolving galaxy 'main sequence' and a mo del in which early- and late-type galaxies form in distinct ways, with early-type galaxies forming in a sudden burst of star formation. 15:15-15:30 David Sobral Email: sobral@strw.leidenuniv.nl Title: Star-forming galaxies over the last 11 Gyrs Abstract: I will present the results from deep and wide narrow-band surveys undertaken with UKIRT, CFHT, Subaru and the VLT; a unique combined effort to select large, robust samples of (mostly) Halpha (Ha) emitters at z=0.40, 0.8, 0.84, 1.47 and 2.23 (corresponding to lo ok-back times of 4.2, 7.0, 9.2 and 10.6 Gyrs) in a uniform manner over 2-10 deg2 in the COSMOS, UDS and SA22 fields. Our samples contain 1000-3000 homogeneously selected Ha sources per redshift and are used to determine the Ha, star-formation rate and stellar mass functions (for star-forming galaxies) of the Universe and their 11 Gyr evolution. We find a strong evolution in the typical SFR (SFR*) from z0 to z2.23, and very little evolution in the mass function of star-forming galaxies, consistent with them having a similar M* since z2. Both the shape and normalisation of our Ha star formation history are consistent with the measurements of the stellar mass density growth, confirming that our Ha analysis traces the bulk of the formation of stars in the Universe up to z2.2. Apart from that strong increase in SFR* from low to high redshift, the properties of the overall star-forming population reveal a remarkable non-evolution in the last 11 billion years, revealing that many of the previously claimed evolutionary trends are a direct consequence of the typical SFRs of galaxies being much higher in the past. 15:30-15:45 Paolo Serra Email: pserra@ias.u-psud.fr Title: Constraints on the cosmic star formation history from the analysis of cosmic infrared background anisotropies with Planck 4


Abstract: The power spectrum of cosmic infrared background (CIB) anisotropies is sensitive to the link between star formation and dark matter halos over the entire cosmic star formation history. We present a mo del that asso ciates star-forming galaxies with dark matter halos and their sub-halos and that has been used by the Planck collaboration to interpret the latest (2013) accurate measurements of the CIB power spectra at all scales. We then discuss constraints on the cosmic star formation history, cosmic dust evolution and dark matter - galaxy bias; finally we present preliminary results from a global analysis of CIB power spectra, number counts and luminosity functions using multiple datasets. 16:15-16:45 Rachel Somerville Invited talk 16:45-17:00 Matt Jarvis Email: matt.jarvis@astro.ox.ac.uk Title: A new calibration of the radio luminosity - star-formation rate relation Abstract: Using the Herschel-ATLAS, along with multi-wavelength imaging and spectroscopy, we have conducted a detailed investigation of the relation between the radio luminosity and star-formation rate in far-infrared selected galaxies. We find a different relation to those proposed previously, with evidence of a non-linearity consistent with theoretical mo dels. We also highlight the consequences this may have for determining the evolution of the star-formation rate density in the Universe using current and future radio continuum surveys. 17:00-17:15 Kirsten Kraiberg Knudsen Email: kraiberg@chalmers.se Title: ALMA and IRAM observations of gravitationally lensed high-z submm galaxies Abstract: Submillimeter galaxies (SMGs) are some of the most extreme starbursts galaxies at high redshift. With luminosities > 1013 Msun and star formation rates (SFRs) > 1000 Msun/yr, these galaxies represent intense episo des in the evolution of massive galaxies. Using gravitational lensing caused by intervening massive galaxy clusters, it is possible to find less extreme SMGs with luminosities 1011 - 1012 Msun and SFRs 100 Msun/yr. These provide a larger contribution to the submm extragalactic background light and could be closer related to the starburst galaxies seen in the lo cal Universe. We have conducted interferometric observations with ALMA and IRAM for four galaxy clusters in the regions where the gravitational magnification would be the highest for high redshift galaxies. I will show the results from these observations. I will particularly fo cus on the ALMA observations of a 50x magnified SMG in the field of A1689, where we are able to determine the lo cation of the starburst region within the galaxy through multiwavelength studies. I will discuss the implications of this in the context of galaxy evolution. 17:15-17:30 James Geach Email: j.geach@herts.ac.uk Title: The SCUBA-2 Cosmology Legacy Survey Abstract: The JCMT SCUBA-2 Cosmology Legacy Survey (S2CLS) is the largest single pro ject to be undertaken with the SCUBA-2 sub-mm camera. The goal of S2CLS is to conduct the most comprehensive survey of sub-mm galaxies (SMGs) at 450 and 850um ever performed. With its wide and deep 5


survey tiers, mapping well-studied extragalactic fields, S2CLS has already amassed an exquisite dataset, including the largest sample of SMGs at 850um ever assembled (over 1000 sources catalogued), and probing further down the 450um luminosity function than has so-far been possible (complementing the wide-area surveys of Herschel by probing below the Herschel/SPIRE confusion limit). A trailblazer for future large-area sub-mm surveys, and a goldmine for exploitation by ALMA, JWST and SKA, S2CLS will revolutionize our understanding of the evolution of starburst galaxies and AGN. In this talk I will describe the survey, its progress and latest scientific results. 17:30-17:45 Chris Hayward Email: cchayward@gmail.com Title: The surprising complexity of the submillimetre galaxy population Abstract: Submillimetre galaxies (SMGs) ­ which are some of the most luminous, rapidly star-forming galaxies in the Universe ­ have long been thought to be predominantly merger-induced starbursts, i.e., 'scaled-up' analogues of lo cal ultraluminous infrared galaxies. However, recent observational evidence and theoretical arguments suggest that the population is significantly more complicated than previously thought. I will present a revised mo del for the SMG population that is based on the results of a combination of dust radiative transfer performed on hydro dynamical simulations of disc galaxies and galaxy mergers and cosmological simulations. I will argue that although merger-induced starbursts contribute to the SMG population, other types of sources also contribute significantly. In particular, early-stage mergers, pro jected multiples in which one or more components are physically unrelated to the others, and isolated discs can all provide significant contributions, depending on the flux density considered. I will discuss recent observational evidence that favours our mo del and present predictions for follow-up observations of SMGs resolved by ALMA. Finally, I will argue that when all of the aforementioned subpopulations are accounted for, the submm number counts are consistent with a standard initial mass function, which is in contrast with some previous claims.

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Wednesday, Septemb er 4
`Galaxy Assembly and Star-formation History I I' session
09:00-09:30 Simon Lilly Email: simon.lilly@phys.ethz.ch Title: What the galaxy population tells us I will discuss several insights into the evolution of galaxies that have been obtained by taking a phenomenological approach to the evolving population of galaxies. This is based on identifying a number of key "simplicities" and understanding the implications and inter-relationships of these. These can be combined into a semi-analytic style mo del with virtually no free parameters that appears, with one or two interesting exceptions, to repro duce reality rather well. 09:30-09:45 Simon Driver Email: spd3@st-and.ac.uk Title: The two-phase evolution of galaxies Abstract: Using the GAMA database we will show galaxy stellar mass functions for the distinct Hubble types (E, S)a, SBC, Sd/Irr) and the distinct components (bulges and discs). Our findings show that 60% of the present day stellar mass is in the form of discs and only 40% in the form of spheroids and classical bulges. This has led us to develop a two-phase mo del of galaxy evolution by which spheroids form by z>1.5 via dynamically hot pro cess (merging/collapse), followed by disc growth through a dynamically cold pro cess (i.e., gas accretion). We compare our mo del to measurements of the cosmic spectral energy distribution from UV to far-IR wavelengths and find strong agreement with our mo del prediction. We will also present results on the evolution of the mass-size relation of spheroids and discs since z<1 and our plans to expand the GAMA pro ject outward in redshift by capitalising on the 100+ HST fields within the GAMA survey fo otprint. 09:45-10:00 Francois Hammer Email: francois.hammer@obspm.fr Title: Formation of the Hubble Sequence during the last 8 Gyr Abstract: Using the deepest and most complete observations of distant galaxies, we investigate the progenitors of present-day large spirals. Observations of z=0.4-0.9, MJ (AB) < 20.3, galaxies include spatially-resolved kinematics, detailed morphologies and photometry from UV to mid-IR. We also selected a sample of nearby galaxies from the SDSS using a single criterion, MJ (AB) < 20.3. Morphological analysis has been done in a perfectly identical way for all galaxies in the two samples. We derived a past Hubble sequence, 6 Gyrs ago, that can be causally linked to the present-day one. Six billions years ago, half of the present-day spirals were starbursts experiencing gas-rich ma jor mergers, evidence for this is provided by their anomalous kinematics and morphologies. This provides a new channel of disk formation, e.g. disks reformed after gas-rich mergers, in agreement with the predictions of state of the art, semi-analytical LCDM mo dels. The first ever established evolution of the baryonic Tully Fisher relation will be presented as well as the expected impact to the missing baryon problem. 10:00-10:15 Anna Cibinel 7


Email: anna.cibinel@cea.fr Title: Resolved star formation on and off the galaxy main sequence Abstract: Lo cal and high redshift star forming galaxies are found to follow a tight relation between star formation and stellar mass (the so-called "main sequence", MS). Our current knowledge of the mechanisms responsible for such regularity as well as of the precise pro cesses which move galaxies up or below the MS is however limited. Using the high-resolution HST data in conjunction with GOODS-Herschel observations we are investigating the morphological and star formation properties across the MS. I will present results concerning the structure of both MS and non-MS galaxies as obtained from resolved stellar-mass and star formation maps up to z2. This analysis allow us to study, e.g., the relative importance of bursts o ccurring in clump sized or centrally concentrated regions with respect to a more diffuse star formation and to compare our results with theoretical predictions of disk or merger-driven instabilities. 10:15-10:30 Wako Ishibashi Email: wako@ast.cam.ac.uk Title: The role of AGN feedback in the evolution of massive galaxies Abstract: Recent observations confirm that massive galaxies at high redshift (z2) are much smaller than galaxies of comparable mass in the lo cal Universe. The compact galaxies are found to evolve significantly in size but relatively little in stellar mass, following a characteristic "inside-out" growth pattern. Two main physical mo dels have been proposed to explain this apparent evolution of massive galaxies: "puffing-up" and "merger" scenarios. We intro duce another possibility, explicitly considering the role of the central active galactic nucleus (AGN), and discuss the plausibility of AGN feedback triggering star formation in the host galaxy. We assume radiation pressure on dusty gas as the driving feedback mechanism. In our picture, stars are formed at increasingly larger radii in the feedback-driven outflow, and gradually build up the outer regions of the host galaxy. We compare this particular form of galaxy growth with the observed evolution of massive galaxies, and discuss a number of implications for the AGN feedback-driven star formation scenario. 11:00-11:15 Enrique Perez-Montero Email: epm@iaa.es Title: Stellar mass, star formation rate and metallicity in the last 10 Gyr: pushing the statistical completeness in galaxy sampling with zCosmos Abstract: I will present the last results on the study of the fundamental relations between some of the integrated properties of galaxies and their evolution as derived from their optical spectra up to redshift approx. 1.5. For this purpose, I will profit from the last release of the zCOSMOS survey, based on LT-VIMOS observations and which involves about 20,000 galaxies with bona-fide determination of the spectroscopic redshift, what implies that this survey is one of the deepest and most complete so far. The auto-consistent analysis of the star-forming galaxies of this survey in combination with those from the SDSS for the lo cal sample, shows that there is an evolution of the mass-metallicity relation that cannot be only explained in terms of high-star formation rate selection effect, as interpreted from the study of the fundamental metallicity relation in the lo cal Universe. I will also present for the first time a study on the evolution of the relation between stellar mass and nitrogen-o-oxygen ratio, which is independent on deviations from the closed-box chemical evolution mo del and, hence, can be more trustable to study the evolution of fundamental relations involving the metal content in galaxies. We will also see the evolution of these properties as a function of other variables such as morphology or nvironment, well 8


derived in all ob jects belonging to the COSMOS field with HST observations. 11:15-11:30 Christian Maier Email: christian.maier@univie.ac.at Title: A VLT-SUBARU synergy to establish the mass-metallicity relation of main sequence galaxies at z<2.5 Abstract: The mass-metallicity relation (MZR) and its evolution is directly connected with the relationships between the stellar mass of galaxies and the dark matter mass of their halo es (Lilly et al. 2013). Obtaining fully consistent metallicities of galaxies over a wide range of redshifts is therefore important. The widely used reference MZR at z>2 from the Erb et al. (2006) study has been affected by the sample selection and unknown AGN contribution, and was based on limited spectroscopic information (1-2 emission lines), yielding large uncertainties in metallicities. To better constrain the MZR of galaxies at z>2, we used VLT and SUBARU near-infrared spectroscopy to measure, for 22 MS galaxies compared to the Erb et al. study, and also an evolution of the fundamental metallicity relation (FMR) compared to the lo cal Universe. New insights into the (chemical) galaxy evolution are gained from a comparison of these observations with the gas-regulation mo del of Lilly et al. (2013), which predicts the MZR and FMR evolution in the context of dark matter halo es of galaxies. 11:30-11:45 Kiyoto Yabe Email: kiyoto.yabe@nao.ac.jp Title: The mass-metallicity relation of star-forming galaxies at z1.4 revealed with Subaru/FMOS Abstract: We present results from NIR spectroscopic surveys with Subaru/FMOS. We observed 1200 star-forming galaxies at z1.4 in the SXDS/UDS field. For 340 ob jects, the Ha emission line was detected significantly. The gas-phase metallicity is derived from the [NII]6584/Ha line ratio. We obtain the mass-metallicity relation at z1.4 by dividing our sample into some stellar mass bins and stacking the spectra. Compiling previous results at various redshifts, we show the mass-metallicity relation evolves relatively smo othly from z3 to z0. The mass-metallicity relation at z1.4 has an intrinsic scatter larger than the observational error. To understand the origin of the scatter, we examined the dependence of other physical parameters on the mass-metallicity relation by using the largest NIR spectroscopic sample ever. The dependence of SFR on the mass-metallicity relation can not be seen clearly. On the other hand, we show that galaxies with smaller size and redder color have higher metallicity at a fixed stellar mass. Although the sample size is still limited, we examined the morphology dependence by using HST/WFC3 images. We show that compact and bulge dominated ob jects appear to show higher metallicity than diffuse and disk dominated ob jects. In this presentation, we will present the detailed results and discuss the possible evolutionary scenario. 11:45-12:00 Ying jie Peng Email: y.peng@mrao.cam.ac.uk Title: The Baryonic Accretion Limit of the Galaxies and the Origin of the Cosmic sSFR9


History Abstract: The observed specific Star Formation Rate (sSFR) history requires the existence of a specific Baryonic Accretion Limit (sBAL) of the galaxy system. The sBAL describes the maximum amount of infalling gas that a galaxy can accept and accrete per unit time. The value of sBAL is of order 3 Gyr-1, determined directly from the observed sSFR history at z > 2. Due to the existence of sBAL, there will be two distinct gas accretion mo des of the galaxy system. At earlier epo chs, the total gas inflow rate of the halo is much larger than the maximum gas accretion rate of the galaxy system that is allowed by the sBAL. At later epo chs, the galaxy system has grown large enough to be able to pro cess and accrete all the infall gas and the galaxy becomes underfed by the gas inflow. The turning redshift, zturn, is the redshift when the two gas accretion phase transits and the sSFR evolution changes redshift dependence. zturn is uniquely set by the value of sBAL. If the sBAL is observed to be around 3 Gyr-1 , zturn is predicted to be around z 2, which is in perfect agreement with the observed sSFR history. With this simple sBAL mo del, we have successfully repro duced the observed sSFR history from the DM halo assembly history and have clearly demonstrated the crucial relationships between the stellar mass assembly history, baryonic mass assembly history and DM halo assembly history. This sBAL mo del also explains why the slope of the sSFR-Mstar relation of the main sequence galaxy is negative and why the gas fraction is strongly anti-proportional to the stellar mass. Finally, we present a simple gas accretion mo del that can naturally explain that the galaxy system can only grow at a limited specific rate in the beginning and that such specific growth rate should be largely independent of halo mass. It also pro duces the correct order of magnitude of the value of the sBAL. 12:00-12:15 Thomas Greve Title: `TRACING STAR FORMATION RELATIONS ACROSS THE CO LADDER AND REDSHIFT' Abstract: We present IR - CO luminosity relations (i.e., log LIR = log LCO + ) across the CO rotational ladder (continuously from J = 1 - 0 to J = 13 - 12) for a sample of 87 (Ultra) Luminous Infra-red Galaxies observed either with Herschel SPIRE-FTS and/or with ground-based telescopes. To extent our analysis to high redshifts, we included 76 (sub)-milllimeter selected dusty star forming galaxies from the literature with robust CO observations and well-sampled far-IR/sub-millimetre spectral energy distributions (SEDs). The derived IR - CO luminosity relations have slopes () consistent with unity over the nearly four orders of magnitude in (critical) gas density (ncrit 102 - 106 cm3 ) probed by the CO transitions studied here. Contrary to previous claims, we rule out any significant trend between and ncrit across this density regime. We argue that a slope of unity is in fact expected, as long as the dense gas fraction do es not change considerably within the sample use to derive the relation. 12:15-12:30 Massimo Stiavelli Email: mstiavel@stsci.edu Title: Galaxy Evolution through the Eyes of Space Telescopes Abstract: (with M. Mountain, I. N. Reid, M. Postman, J. Lotz) We will review the wurruld-beating scientific contributions of the Hubble Space Telescope on our understanding of galaxy evolution. We will show how important keys to Hubble success were the intro duction of large non-proprietary data sets such as the Hubble Deep Field, the Great Observatories Origins Deep Survey, the Hubble Ultra Deep Field, and, more recently, the Multi-Cycle Treasury Programs and the Frontier Fields. Past progress has pushed the redshift frontier where studying the physical properties of galaxies is possible and has highlighted the need for more sensitive instrumentation in the near-IR. This limitation will be superceded 10


by the James Webb Space Telescope currently in development and we will review some of the expected breakthrough from the JWST. While JWST will be fundamental to answer questions on the earliest times of galaxy formation, other telescopes under considerations such as ATLAST and AFTA will provide significant capabilities to study the evolution of galaxies.

`Distant Galaxy Clusters and the Role of Environment' session
14:15-14:45 Rashid Sunyaev Invited talk 14:45-15:00 Mark Bro dwin Email: bro dwinm@umkc.edu Title: The Era of Star Formation in Galaxy Clusters Abstract: I will describe the emerging evidence for an epo ch of significant growth of cluster galaxies at z 1.5. New observations finally rule out the simple monolithic collapse mo dels that, despite being unphysical (or at least unhierarchical), adequately describe cluster evolution at z < 1. Measurements of rapid evolution in rest-frame near-infrared luminosity functions, non-passive evolution in color-magnitude relations, and enhanced rates of mergers, star formation and AGN activity, all suggest the z 1.5 era is a very active one in the formation and assembly of massive cluster galaxies. 15:00-15:15 Tadayuki Ko dama Email: t.ko dama@nao.ac.jp Title: The progenitors of early-type galaxies under rapid construction at z2 Abstract: Our Mahalo-Subaru pro ject has been mapping out star forming activities at the peak epo ch of galaxy formation in some proto-cluster candidates and in a general field (SXDF-UDS-CANDELS) at 1.51.5 traced by line emitters on top of continuum selected cluster member candidates. These serve as ideal laboratories for us to investigate the impact of environment upon galaxy formation pro cesses, such as star formation and AGN activities triggered by galaxy-galaxy interaction. By comparing the properties of star forming galaxies with those in the general field at z2, we address how the progenitors of present-day cluster early-type galaxies form and evolve along with the growth of clusters themselves. We find that galaxies in high density environments tend to be more masive, bursty and dusty, suggesting a biased galaxy formation that involvs dusty star forming activities. 15:15-15:30 Simona Mei Email: simona.mei@obspm.fr Title: The assembly of galaxy clusters at z2 : recent results from the CANDELS survey Abstract: We will present the properties of galaxies in clusters at the epo ch in which they are assembling. We will discuss galaxy distribution, morphology and scaling relations and compare them to more evolved lower redshift clusters and the field.

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15:30-15:45 Ian McLean Email: mclean@astro.ucla.edu Title: Multi-ob ject infrared spectroscopy of high-z galaxies. Abstract: A powerful new to ol for studying the high redshift universe is now operational at the W. M. Keck Observatory. Known as MOSFIRE, for Multi-Ob ject Spectrometer For Infra-Red Exploration, this large, vacuum-cryogenic instrument has the unique ability to select up to 46 individual ob jects in the field of view and then record the near-infrared spectrum of all 46 ob jects simultaneously. A robotic mechanism inside the vacuum chamber reconfigures the distribution of tiny slits in the fo cal plane in under six minutes. I will describe some of the technical challenges we overcame and illustrate MOSFIRE's performance with spectra for galaxy clusters at z=2-3. Infrared instruments have come a long way since I developed the first infrared camera at ROE (1984-86) under Malcolm Longair's leadership. 16:15-16:30 Stacey Alberts Email: salberts@astro.umass.edu Title: The Evolution of Dust-Obscured Star Formation Activity in Galaxy Clusters Abtrsact: Many outstanding questions remain about the role of the most extreme environments in galaxy evolution: at what epo ch do galaxy clusters transition from their characteristic passive evolution to the active star formation necessary for their mass assembly? How are the pro cesses which drive cluster galaxy evolution different from the field? In this study, we leverage a complete catalog of 300 ( 1014 Msun) clusters over the 9 square degree Bo otes field with deep Herschel imaging to analyse the star formation activity in cluster galaxies out to z2. Our analysis is two-fold: 1) we perform a statistical stacking analysis of mass-limited samples of cluster and field galaxies using SPIRE 250um imaging over the redshift range z=0.3-1.5. We find that the average star formation rate in cluster galaxies is evolving more rapidly than in the field, rising to match field star formation levels at z1.5. 2) We use unique, deep PACS 100 and 160um imaging of 11 spectroscopically-confirmed clusters at z=1.1-1.8 to study the properties of infrared bright cluster galaxies (>100 Msun/yr) as a function of redshift and cluster-centric radius. Combined with ancillary data, we determine the star formation, dust, and AGN properties of the most active cluster galaxies and tie the evolution of these properties back to environment using a control field sample. With these two studies, we constrain the pivotal epo ch of dust-obscured star formation activity and mass assembly in the most extreme structures in the Universe. 16:30-16:45 Kelley Hess Email: hess@ast.uct.ac.za Title: TEvolution in the HI Gas Content of Galaxy Groups: Pre-processing and Mass Assembly in the Current Epoch Abstract: We analyze the distribution and the neutral hydrogen gas content of galaxies in groups as a function of their parent dark matter halo mass to reveal pre-pro cessing of the HI with mass assembly in groups. The Arecibo Legacy Fast ALFA survey .40 data release allows us, for the first time, to study the HI properties of over 740 galaxy groups in the volume of sky common to the Sloan Digital Sky Survey and ALFALFA surveys with dark matter halo masses between 1012 - 1014.8 Msun. All the ALFALFA galaxies have SDSS optical counterparts and we assigned HI detections a group membership based on an existing magnitude/volume-limited SDSS DR7 group/cluster catalog. Additionally, we assigned group "proximity" membership to HI detected ob jects that fall below the limiting optical magnitude­thereby not contributing substantially to the estimate of the group stellar mass, but signif12


icantly to the total group HI mass. We find that only 25% of all HI detected galaxies reside in groups or clusters, in contrast to approximately two-thirds of all optically detected galaxies. We stack optical and HI detections in groups as a function of dark matter halo mass to reveal evolution in the spatial distribution of HI detected members. Intermediate mass halos already begin the resemble clusters with gas rich ob jects preferentially residing on the outskirts. Finally, we find that the lowest HI mass ob jects lose their gas first as they are pro cessed in the group environment. We compare our results to those of cosmological simulations predicting HI selected halo o ccupation distributions. It is evident that the infall of gas rich ob jects is important to the continuing growth of large scale structure at the present epo ch. 16:45-17:00 Yen-Ting Lin Email: ytl@asiaa.sinica.edu.tw Title: The Stellar Mass Growth of Brightest Cluster Galaxies in the IRAC Shallow Cluster Survey Abstract: The details of the stellar mass assembly of brightest cluster galaxies (BCGs) remain an unresolved problem in galaxy formation. We have developed a novel approach that allows us to construct a sample of clusters that form an evolutionary sequence (that is, the clusters on the sequence are expected to evolve into each other), and have applied it to the Spitzer IRAC Shallow Cluster Survey (ISCS) to examine the stellar mass evolution of BCGs in progenitors of present-day clusters with mass of 3x1014 Msun. We follow the cluster mass growth history extracted from a high resolution cosmological simulation, and then use an empirical metho d that infers the cluster mass based on the ranking of cluster luminosity to select high-z clusters of appropriate mass from ISCS to be progenitors of the given set of z=0 clusters. We find that, between z=1.5 and 0.5, the BCGs have grown by a factor of 2.3, which is well-matched by the predictions from a state-of-the-art semi-analytic mo del (Guo et al. 2011). Below z=0.5 we see hints of differences in behavior between the mo del and observation. While the observed BCGs show only a small increase in stellar mass content down to z0 (<10%), , the mo del BCGs appear to exhibit an accelerated growth below z=0.5; that is, 50% of the final mass of the mo del BCGs is acquired between z=0.5 and 0. Such a contrast suggests the perio d of z=00.5 is potentially key in differentiating mo dels of BCG assembly history. 17:00-17:15 Thijs van der Hulst Email: vdhulst@astro.rug.nl Title: Galaxies in Voids: special or not? Abstract: The Void Galaxy Survey (VGS) is a multiwavelength survey of 60 void galaxies. Each of the galaxies lies in the interior of the geometrically identified voids in the SDSS DR7 redshift survey. Imaging in HI, Halpha, the UV, near-IR and in the optical provide information about the star formation properties of these galaxies and the available gas reservoir. The main goal is to determine whether the evolution of galaxies in these pristine environments follows the same path as in denser environments. It do es to a large extent, though there appear to be subtle differences. 17:15-17:30 Richard Tuffs Email: Richard.Tuffs@mpi-hd.mpg.de Title: The Evolution of Spiral Galaxies in the Group Environment Abstract: Although the pro cess by which galaxies obtain the gas needed for star-formation is amongst the most fundamental controlling the formation of the baryonic structure in the Universe, there is very 13


little in the way of empirical evidence with which to constrain theoretical mo dels. In particular, the postulated environmental dependencies of this pro cess, although widely mo delled, remain largely unconstrained. Here we present a definitive quantitative study of the effect of the group environment on starformation rates (SFRs) of spiral galaxies in the lo cal Universe, using the multiwavelength photometric and spectroscopic data (complete to r 19.8) from the Galaxy And Mass Assembly (GAMA) survey, in combination with the GAMA catalogue of groups of galaxies of Robotham et al. (2011). SFRs are measured using space-borne UV data from the dedicated GALEX-GAMA survey of the entire 150 square deg fo otprint of GAMA covered to date by the spectroscopic survey. The analysis is done for a volume-limited sample of spiral galaxies spanning a range in stellar mass from 109.5 to 1011 Msolar hosted by groups spanning a range in dynamical mass from 1012 to 3 в 1014 Msolar. We have carefully isolated the delicate imprint of the galaxy-intergalactic medium (IGM) interaction on SFR from other potential environmental influences (such as galaxy-galaxy interactions), and from the strong systematic dependence of SFR on stellar mass for spiral galaxies, as calibrated on GAMA galaxies in the field. Spiral galaxies are identified using a new, purpose-built robust metho d for selecting large samples of morphologically-defined galaxies by photometric proxies, allowing us to break the degeneracy between effects on SFR of galaxy-IGM interactions and the strong differences in star-formation activity observed between rotationally- and pressure-supported systems. The fidelity and statistical power of the study is further enhanced through the application of a radiation transfer analysis (calibrated on a subset of galaxies with available FIR/submm photometry), which utilises the measured angular sizes and inclinations of each galaxy to correct for the strong and ob ject-specific effects of dust attenuation on the emergent UV flux from the spiral disks. We use the results to identify and quantify the influence of the dynamical mass of the group halo es on gas flows between the IGM and the interstellar medium of central and satellite spiral galaxies, as mediated by feedback on the IGM driven by star-formation and AGN activity, and by gas-dynamical interactions between the spiral galaxies and the IGM. 17:30-17:45 Nicky Brassington Email: n.brassington@herts.ac.uk Title: The Behaviour of Cold Gas in Damp-Mergers Abstract: It is widely believed that very few galaxies exist to day that have not been formed or shaped in some way by an interaction with another galaxy. These interactions play a ma jor role in the evolution of galaxies by triggering star formation and nuclear activity. However the parameters that influence this enhanced activity are po orly understo o d. The Spitzer Interacting Galaxies Survey (SIGS) is addressing this question by using IR data obtained with the Spitzer Space Telescope to study a large sample of 103 galaxies in different stages of interaction. In this presentation I will provide an summary of the sample and present the results from the photometric analysis. I will also discuss our recent work on HI & CO data which allow us to determine the properties of the ISM of these systems. I will specifically fo cus on the interacting systems that contain one gas-rich and one gas-po or galaxy; the damp-mergers. Such systems provide us with the opportunity to study how cold gas from the gas-rich galaxy is affected by its companion and thereby, in conjunction with the Spitzer data, provide constraints on the relationship between the ISM and star-formation in interacting systems containing a gas po or system.

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Thursday, Septemb er 5
`AGN and Radio Astrophysics' session
09:00-09:30 Tim Heckman Invited talk Claudia Cicone Email: c.cicone@mrao.cam.ac.uk Title: Revealing the AGN Negative Feedback Through Broad Wings of CO Emission Lines Abstract: Understanding the negative feedback mechanisms, responsible for regulating and quenching star formation in galaxies, represents a crucial step in solving some of the ma jor open problems in galaxy formation and evolutionary mo dels. In particular, negative feedback from AGNs is invoked by theoretical mo dels to explain the red-and-dead properties of nearby massive galaxies. The recent observations of massive molecular outflows in nearby quasar host galaxies constitute a ma jor breakthrough in this field. However, so far, these outflows have been found and studied only in few, exceptional galaxies and little is known about their origin and physics. I will present new detections of powerful molecular winds in a sample of AGNs and ULIRGS, traced by broad wings of the CO(1-0) emission line, observed with IRAM-PdBI. By including data from the literature, I have assembled a total of 16 molecular outflows detections in lo cal galaxies, spanning a wide range of AGN and starburst activity. I have found that, while in starburst-dominated ob jects, outflow rates and SFRs are comparable, outflow rates are significantly "bo osted" in AGNs, by a factor that increases with the AGN contribution to the total bolometric luminosity. I have discovered, for the first time, a tight correlation between outflow rate and AGN luminosity. Outflow kinetic power and AGN power are also correlated, and their ratio is very close to the expectations of mo dels of AGN feedback (i.e. 5%). These findings point to an AGN origin of these massive molecular winds. Interestingly, my results show that only in a few of the starburst-dominated sources the outflow energetics are fully consistent with entirely star-formation driven winds; in most cases, we cannot exclude that a low-luminosity AGN (or, alternatively, an AGN that has already turned off ), is instead the main power source of the molecular outflow. 09:45-10:00 Bram Venemans Email: venemans@mpia.de Title: The host galaxies of the most distant quasars Abstract: Luminous quasars at high redshift are powered by supermassive black holes. These massive black holes are thought to be lo cated in the progenitors of the massive early type galaxies we see in the lo cal Universe. Therefore, studying the host galaxies of the most distnat quasars enables us to study the formation of massive galaxies in the early Universe. Recently, using wide field infrared surveys, we successfully discovered at least 4 quasars at z ї6.5 with a central black hole of >109 solar mass. In this talk I will present ALMA and Plateau de Bure Interferometer observations of the host galaxies of these 4 z ї6.5 quasars. I will discuss our results and the implications for massive galaxy formation at high redshift and our understanding of the relation between the black hole mass and the bulge mass of galaxies. 10:00-10:15 Manda Banerji Email: m.banerji@ucl.ac.uk 15


Title: A New Population of Hyperluminous Dusty Quasars with Massive Starburst Host Galaxies at z2 Abstract: A new generation of wide-field astronomical surveys at infra-red to millimeter wavelengths has opened up discovery space for the most massive, intrinsically rare galaxies in the early Universe as well as allowing us to catch galaxies in short-lived phases of their evolutionary history. With new infra-red surveys such as the UKIDSS Large Area Survey, VISTA Hemisphere Survey and WISE All Sky Survey, we have discovered a population of extremely red Type 1 broad-line quasars at z2 (Banerji et al. 2012, 2013a) which are to o red to be detected in wide-field optical surveys like the SDSS and have therefore been unstudied thus far. These quasars show strong evidence for dust extinction arising at large scales in their host galaxies and therefore plausibly represent the most massive starburst galaxies at z2 that are in the pro cess of transitioning to UV-luminous AGN. The median dust-extinction for the sample is Av2.5, comparable to the dust-extinction seen in submillimeter galaxies (SMGs) at similar redshifts. The reddest quasar in our sample has a dust-extinction of Av4-6 and is one of the most bolometrically luminous and massive black-holes known at these redshifts. Despite this, it is completely absent from optical surveys and has therefore not been discovered until now. I will present results from our extensive spectroscopic follow-up campaign of this rare population of massive, dusty starbursts in the pro cess of turning into UV-luminous quasars. The new spectroscopic data has allowed us to quantify the amount of dust-extinction and properties of the central black-hole in these quasars and place initial constraints on the fraction of reddened Type 1 quasars that have been missed by surveys like SDSS. I will also discuss some new results from Herschel that have allowed us to study the far infrared properties of the quasar host galaxies, and demonstrated unambiguously that the hyperluminous reddened quasars reside in some of the most extreme starbursts found at z2. Finally I will end by discussing how this new population could help distinguish between different mo dels of massive galaxy formation and co-eval galaxy and black-hole growth. 10:15-10:30 Martin Elvis Email: elvis@cfa.harvard.edu Title: Feedback and the Multiple Forms of the Obscuring "Torus" in AGNs Abstract: The intermittently active supermassive black holes in galaxy nuclei are an integral part of galaxy evolution. Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas in the optical-UV to X-ray continuum and in the broad permitted emission lines, i.e. the inner regions of the nucleus. The level of obscuration, as measured by X-ray column density spans a range of >1000. It is normally assumed that the obscuration o ccurs in an oblate obscuring torus, that begins at the radius (0.1- a few pc) at which the most refractive dust can remain solid. This torus is normally mo deled as a donut-shaped region of molecular gas with large scale-height. This mo del elegantly accounts for many phenomena, it do es not hold up to detailed tests. Instead the obscuration in AGNs must o ccur on a wide range of scales and is due to a minimum of three physically distinct absorbers. The parsec scale emission may be due to a warped disk. The form of AGN obscuration has implications for feedback into the ISM of the host and enrichment of the IGM. 11:00-11:30 Darren Croton Email: Title: Simulations and modelling of feedback processes in galaxies (Invited) Much progress has been made in recent years in our understanding of the co-evolution of galaxies and AGN, and their connection to the underlying large-scale structure. In this talk I will discuss simulation 16


and mo deling techniques that bridge theories of galaxy and black hole formation with the properties of observed galaxy populations. In addition, I will discuss a number of open questions important for extra-galactic astronomy and cosmology, and explain how future large-scale surveys and galaxy formation mo dels may jointly address them. 11:30-11:45 Andrew Blain Email: ab520@le.ac.uk Title: Dusty monsters stare from WISE Abstract: I will describe some of the most luminous and unusual AGN found over the sky from the WISE mission. Selected by bright mid-IR mission, these galaxies have expanded the zo o of dust-enshrouded galaxy properties, including ultrahot AGN-dominated SEDs, large asymmetric Lyman-alpha halos, and unusual compact radio properties. They are some of the most plausible candidates for the most extreme snapshots of AGN-galaxy feedback events in the evolution of galaxies, and could be the 21st century equivalents of the 3C radio-galaxies for decades of future study. 11:45-12:00 G. (Pepi) Fabbiano Email: pepi@cfa.harvard.edu Title: Exploring galaxy evolution with Chandra Abstract: This talk will discuss astrophysical signatures of the currently accepted scenario of galaxyMBH evolution through collapse, merging and feedback, which emerge strongly in the X-ray band, and can be studied with the high spatial resolution and asso ciated spectral capabilities of the Chandra X-ray Observatory. Chandra observations are providing detailed views of the hot plasmas resulting from gravitational collapse and merging, and of the interaction of the MBHs with the hot and co oler interstellar medium. These include: snapshots of the physical and chemical evolution of the interstellar medium during different stages of galaxy merging, from interacting spirals to young or rejuvenated ellipticals; the discovery of highly obscured close AGNs pairs, not only in well-know mergers, but also in apparently regular galaxies, pointing to the importance of mergers in galaxy and MBH evolution; and constraints on AGN feedback from direct observations of the circumnuclear regions of nearby active galaxies. 12:00-12:15 Michaela Hirschmann Email: mhirsch@oats.inaf.it Title: BH growth and AGN evolution in large cosmological simulations Abstract: In this study, we present a detailed, statistical analysis of BH growth, the evolution of AGN number densities and their connection with host galaxy properties using fully, cosmological hydro dynamic simulations run down to z=0. The simulations self-consistently follow star formation, black hole growth and asso ciated feedback pro cesses and provide a large volume ((180Mpc)3 ) with a reasonable resolution allowing for a direct, statistical comparison with recent, observational surveys. The simulations can match several present-day black hole properties. Additionally they are found to be in remarkably go o d agreement with the observed evolution of the AGN luminosity function when considering both the low and the ­ for the first time accessible ­ high-luminosity end - since z=3. Thus, simulations can automatically account for the observed downsizing trend in the AGN number density evolution as a consequence of the complex light curves of black holes resulting from the detailed hydro dynamics followed in the simulations. At higher redshifts, our results get affected by resolution effects, however, with increasing resolution and decreasing box size, the simulations can repro duce the low-lumosity end of the AGN luminosity function up to z=5. Finally, the simulations are able to qualitatively predict observed 17


trends excess but at ones o

between AGN and their host galaxy properties, e.g. AGN hosts do not reveal any significant of star-bursting activity, they roughly follow the main-sequence of normal, star-forming galaxies, a given stellar mass the hosts of very luminous AGN tend to be slightly more quiescent than the f normal galaxies.

12:15-12:30 Nicholas Seymour Email: nicholas.seymour@csiro.au Title: The Growth of Massive Black Holes at High Redshift Abstract: High redshift radio galaxies (HzRGs) are unique markers of the co eval formation of massive galaxies and their central black holes within the of peaks of dark matter over-densities in the early Universe. As such they are important laboratories for studying the formation of massive galaxies containing active galactic nuclei and how AGN activity affects the host galaxy and environment. I shall present results from `Pro jet HeRGE', a systematic study of 71 high redshift radio galaxies (z ї1, L500M H z ї102 6 W/Hz) using Spitzer and Herschel photometry. From these data we are able to constrain the stellar mass, the AGN power and the SFR of these sources and, hence obtain a measure of the overall evolutionary state of the system. I shall present evidence for the early growth of black holes relative to their host galaxies as well as a general census of the HzRG population. 14:15-14:30 Philip Best Email: pnb@ro e.ac.uk Title: The evolving role of radio-AGN feedback Abstract: I will discuss the evidence that the radio-loud AGN population is composed of two fundamentally distinct classes of radio source. Using a large sample of lo cal radio-AGN selected from the SDSS, I will show that it is the Eddington-scaled accretion rate on to the black hole which gives rise to this dichotomy. I will demonstrate that it is the radiatively inefficient (LERG) population which is responsible for radio-AGN feedback effects, controlling the growth of massive galaxies. Combining a set of seven flux-limited radio samples out to redshift 1, I show the first independent measurement of the cosmic evolution of this population (as distinct from that of the quasar-like radio-AGN), and hence of radio-AGN feedback. I discuss the prospects for further advancement of this work to still higher redshifts using upcoming facilities such as LOFAR. 14:30-14:45 Huub Rottgering Email: rottgering@strw.leidenuniv.nl Title: LOFAR and studies of clusters, starbursts and AGN Abstract: LOFAR is a new radio telescope that will open up the ultra low frequency radio sky for astronomical studies. One of the aims of LOFAR is to survey the entire northern sky in the range 20-200 MHz. The design of the LOFAR surveys has been driven by three key topics that are directly related to the formation of massive black holes, galaxies, and clusters. The fourth key topic is using the vast area of new parameter space for serendipitous discovery. In addition to the key topics, the LOFAR surveys will provide a wealth of unique data for a huge number of additional important topics. In this talk the results of the first half year of LOFAR operations will be presented. Initial results will be shown on (i) radio emission from colliding clusters constraining the physical properties of low mach sho cks, (ii) radio emission from star bursting galaxies, delineating how free-free absorbing gas might be distributed, and (iii) deep observations of famous fields (Bo otes, Cosmos, XMM-LSS) that enable evolutionary studies 18


of AGN accretion pro cesses. 14:45-15:00 Ray Norris Email: raypnorris@gmail.com Title: Exploring galaxy evolution with next-generation radio surveys Abstract: Several next-generation radio surveys are being planned, such as the Evolutionary Map of the Universe (EMU) to be undertaken on the Australian SKA Pathfinder (ASKAP) telescope. EMU will detect and catalog about 70 million galaxies, increasing thirty-fold the number of known radio sources. Such large numbers enables a new approach to the study of galaxy evolution, taking data-intensive approaches to sequence the galaxies rather than studying individual galaxies. To interpret these large datasets will be challenging, and new approaches and algorithms will be needed to turn these data into science. 15:00-15:15 Wiphu Rujopakarn Email: wiphu@as.arizona.edu Title: Extinction-Independent Morphologies of Star Formation and AGN from a Jansky VLA Deep Field Abstract: We conducted one of the deepest extragalactic radio surveys to date using 64 hours of Jansky VLA observations at 4-8 GHz. Our primary goal is to study the extinction-independent morphologies of star formation and AGN to understand how galaxies formed stars and were assembled during the peak epo ch of the cosmic star formation rate history and galaxy assembly. The target field is a 50 arcmin sq. region of the UKIDSS Ultra-Deep Survey (UDS) that has Hubble/WFC3 imaging and grism spectroscopy from CANDELS and 3D-HST. This single-pointing survey has pro duced an image with an RMS noise of 0.5 uJy/beam, which is capable of detecting and resolving Arp 220-luminosity galaxies at z > 2. Our 0.3" resolution image (2.5 kpc at redshifts 1-3) spatially resolves >70into diverse morphologies, showing that the sources range from point-like AGNs to star-forming galaxies extending over a few kpcs. Here, we present the extinction-free morphologies, morphological comparison with CANDELS, spatially-resolved spectral indices over 4 GHz bandwidth that we use to identify AGNs, and implications on the mo des of star formation (in-situ or starburst) and roles of mergers in assembling galaxies. 15:15-15:30 Anna Kapinska Email: anna.kapinska@port.ac.uk Title: Anti-hierarchical growth and feedback history of powerful radio galaxies Abstract: Understanding evolutionary patterns and energy budget of supermassive black holes across cosmic time is crucial for studies of formation and evolution of galaxies and galaxy clusters. Here, based on rigorous population study we estimate the total energy pro duced and injected into environments by Fanaroff-Riley II radio galaxies as a function of redshift. Although radio galaxies are thought to regulate the growth of galaxies, little work has been done before in quantifying the scale of FRII kinetic feedback. Our results indicate that the FRII radio sources follow the anti-hierarchical growth of galaxies (cosmic downsizing). Furthermore, our results on the kinetic luminosities and available energy of these sources suggest that powerful FRIIs are able to quench clusters' co oling flows at least for the duration of their lifetimes. In this talk I will also highlight how the new radio facilities can uniquely contribute in our study of the cosmic history of the kinetic AGN feedback.

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15:30-15:45 Stas Shabala Email: Stanislav.Shabala@utas.edu.au Title: The relationship between lobe luminosity and kinetic power of AGN jets Abstract: Accurate measurement of kinetic power of AGN jets is important to three areas of astrophysics: (1) jet generation mechanisms; (2) studies of jet dynamics; and (3) the role of AGN feedback in galaxy formation and evolution. However, measuring jet power is difficult. The lack of reliable empirical metho ds has resulted in the widespread use of radio luminosity as a proxy for jet power. We present a new metho d of measuring jet power in FR-II radio galaxies, based on the observed parameters of jet terminal hotspots. We compare the jet power - lobe luminosity relation derived for our sample with that obtained for FR-I radio galaxies based on X-ray cavity measurements. Somewhat surprisingly, we find approximate agreement between these relations, despite mounting evidence in the literature favouring vastly differing compositions and energy budgets in these two classes of radio galaxies. We use our hotspot measurements to show that FR-II radiative efficiency is sensitive to radio galaxy size, in agreement with predictions of dynamical mo dels. Any observed jet power - radio luminosity relation is therefore sensitive to sample selection effects. This dependence explains, at least in part, the coincidence of the jet power - lobe luminosity relations for FR-I and FR-II sources. Our findings are important to interpretation of next-generation survey data from LOFAR, ASKAP and WSRT-Apertif. 16:15-16:45 Judith Croston Jets from radio-loud AGN are now known to play an important role in galaxy evolution in the nearby Universe. Their role at higher redshifts remains uncertain. In the near future, deep extragalactic surveys with next-generation radio telescopes will lead to an unprecedented view of the low-luminosity radio jet population to high redshifts. Translating radio-galaxy population statistics into a robust understanding of the evolving role of radio jet feedback in galaxy evolution requires solving decades-old uncertainties in the physics, energetics and environments of radio-loud AGN. I will discuss recent advances in this sub ject, driven by the powerful combination of X-ray and radio observations, and how LOFAR observations of nearby radio galaxies can help 16:45-17:00 Marios Karouzos Email: mkarouzos@astro.snu.ac.kr Title: Awaking the giant: Environmental hints on AGN triggering Abstract: Although the link between activity in the nuclei of galaxies and galactic mergers has been under intense scrutiny, it is still unclear to what extent and for which populations of active galaxies merger-triggered activity is relevant. Studies of the morphologies of galaxies that directly probe the fraction of ongoing mergers in AGN samples are usually plagued by sensitivity limitations, either in terms of faint merging features or altogether faint host galaxies comparably to their active nuclei. The environment of AGN on the other hand allows an indirect probe of the past merger history and future merger probability of these systems, suffering less from sensitivity issues while extending to higher redshifts. Here we use the first data release from the new near-IR VISTA-VIDEO survey to investigate the environment of radio and X-ray selected AGN out to redshift z=4. Using both number density and closest neighbor density parameters we test whether active galaxies inhabit denser environments and study these over-densities in terms of both distance to the AGN and its luminosity. We find strong evidence for both X-ray and radio-selected AGN to reside in over-dense environments at small scales. A trend for more luminous AGN residing in more over-dense environments is also found. On the other 20


hand we find a non-negligible fraction of our AGN sources inhabiting practically empty environments, after accounting for selection and observational biases. We argue that given the depth of the VIDEO survey we are able to reveal AGN residing in host galaxies of lower-mass compared to previous studies. Thus a population of AGN living in under-dense environments is observed. Our findings therefore imply that it is mostly the coupling between AGN and the mass of their host galaxies that apparently places AGN in denser environments, rather than a causal link between AGN and mergers. The above are discussed in terms of current theories of AGN triggering. 17:00-17:15 Jose Sabater Email: jsm@ro e.ac.uk Title: The competing role of environment and one-on-one interactions in radio and optical nuclear activity Abstract: Active galactic nuclei (AGN) are closely related to galaxy formation and evolution. The black holes that power AGN are found in all massive galaxies and their masses are tightly correlated with both the masses and the velo city dispersions of the stellar bulges. Furthermore, AGN may play an important role in the feedback mechanisms that control the growth of massive galaxies. The possible effect of the AGN may also depend on the type of AGN triggered and its feeding mechanisms: (a) a high-excitation radiatively-efficient feeding mo de that pro duces AGN that are mainly detected as optical or X-ray AGN (and in some cases also as high excitation radio AGN) and (b) a low-excitation radiatively-inefficient mo de that pro duces radio AGN. In turn, the feeding mo de of the AGN can be controlled by galaxy interactions and the environment. We present a study of the prevalence of optical and radio nuclear activity with respect to the environment and interactions in a sample of SDSS galaxies. The aim is to determine the independent effects of distinct aspects of source environment on the triggering of different types of AGN. We defined and used three environmental parameters to trace different aspects of environment and interaction and removed the possible correlations between them using a principal component analysis. A stratified statistical metho d that takes into account the effect of possible confounding factors like the galaxy mass was applied. Overall, our results agree with a scenario in which the mechanisms of accretion into the black hole are determined by the presence and nature of a supply of gas, which in turn is controlled by the local density of galaxies and their interactions. 17:15-17:30 Judith Ineson Email: ji1g10@soton.ac.uk Title: The large-scale environments of radio-loud AGN Abstract: In the Chandra Large Pro ject ERA (Environments of Radio-loud AGN), we have characterised the cluster environments of a sample of 26 radio-loud AGN at z 0.5 that covers three decades of radio luminosity. This is the first systematic X-ray environmental study at a single epo ch, and has allowed us to examine the relationship between radio luminosity and cluster environment without the problems of Malmquist bias. We will present evidence for a correlation between radio luminosity and host cluster X-ray luminosity, as well as tentative evidence that this correlation is driven by the sub-population of low-excitation radio galaxies. We are now comparing our z0.5 sample with a sample of radio galaxies at z<0.1 to lo ok for evidence of evolution with epo ch. We will present our preliminary findings and discuss the implications of our results for AGN feedback in galaxy formation mo dels and cosmological simulations.

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Friday, Septemb er 6
`Gas in Galaxies' session
09:00-09:30 Danail Obreschkow (invited) Email: danail.obreschkow@icrar.org Title: Gas Dynamics in Galaxies (invited) Abstract: Recent detections and simulations of cold gas in galaxies at high redshift (z) paint a surprising picture, where cold gas dominates the baryonic mass in the key era of star formation at z=2-3. In this era the gas turbulence seems to be significantly higher than to day, with dispersion supported disks being quite common. Although not conclusively understo o d, this turbulence seems to be both a consequence and a defining factor of star formation. A linked phenomenon is a strong cosmic evolution in the mass ratio between molecular and atomic gas, predicted to scale as (1 + z )(1.5-2) from z=0 to z=3. Apart from playing a key role in galaxy evolution, cold gas, especially atomic hydrogen, also traces the motion and kinematics of galaxies. Mo dern applications range from small-scale studies of differential galaxy rotations, merger dynamics and feedback pro cesses to large-scale cosmological applications. For instance, new data from the HIPASS and ALFAFA surveys, as well as mo dern high-resolution N-bo dy simulations led to the first gas-based constraints on the nature of dark matter, and hydrogen maps pro duced by the future SKA promise to become the best tracer of cosmic structure all the way back to the Epo ch of Reionization. 09:30-09:45 Timothy Davis Email: tdavis@eso.org Title: Probing the cold phase ISM in early-type galaxies with Herschel, IRAM and CARMA Abstract: Massive early-type galaxies can no longer be considered as purely read and dead systems, thanks to the discovery that a sizeable proportion have atomic/molecular gas and dust reservoirs. We are carrying out a comprehensive survey of the cold and warm ISM in the volume-limited ATLAS-3D sample of early-type galaxies; our data include CO and HI maps, detections of high density molecular tracers, optical emission line ratios, and Herschel spectroscopy of the [CII], [OI] 63micron, and [NII] 122 and 205 micron lines plus the high-J CO ladder. These observations of "normal" early-type galaxies in the lo cal universe provide a useful comparison sample for local spirals, radio galaxies, central galaxies of co oling flow clusters, and systems at higher redshift. Our data also allow us to probe the influence of a galaxy's cluster or group environment, AGN activity, and dynamical state on the properties of its ISM. For example, the "normal" field early-type galaxies have more extended molecular disks, that are often misaligned from the stellar bo dy of the galaxies, and [CII]/FIR ratios in the range o ccupied by normal spirals. In contrast the virialized Virgo Cluster members, while being as molecular gas rich as ETGs in the field, have more compact aligned molecular reservoirs, and show unusually large [NII]/[CII] and small [CII]/FIR ratios, highlighting the more subtle effects of the cluster environment on the cold ISM. CO and MIR maps also enable us to make spatially resolved measures of the star formation rate and the gas depletion timescales, suggesting these massive galaxies have lower star-formation efficiencies than one might expect based on canonical star-formation relations. All of this information can be combined with our knowledge of the galaxies' stellar populations (ages, metallicities & kinematics) for insights into the formation and evolution of early-type galaxies, and enable us to make predictions which will be directly testable in the era of ALMA, CCAT and the LMT.

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09:45-10:00 Claudia Lagos Email: clagos@eso.org Title: The atomic and molecular gas content of galaxies Abstract: The latest observations of the carbon monoxide and atomic hydrogen contents of lo cal and high-redshift galaxies, coupled with how these correlate with star formation activity, have revolutionized our ideas about how to mo del star formation and the interstellar medium in a galactic context. A successful theory of galaxy formation has to explain some key facts: (i) high-redshift galaxies have higher molecular gas fractions and star formation rates than lo cal galaxies, (ii) scaling relations between the molecular, atomic and stellar mass of lo cal galaxies show a close to linear relation between the molecular and stellar mass and almost no correlation between atomic and stellar mass, and (iii) the global abundance of atomic hydrogen evolves very weakly with time. I will describe the approach of semi-analytic mo dels and the efforts done with them to put together these pieces in an ab-initio galaxy formation mo del. I will present observable predictions and what still needs to be done in these mo dels to allow robust testing by the new observations expected from e.g. ASKAP, SKA, ALMA, PdBI. 10:00-10:15 Matt Bothwell Email: matthew.bothwell@gmail.com Title: A fundamental relation between the metallicity, gas content, and stellar mass of local galaxies Abstract: Recent results have suggested that the well known mass-metallicity relation has a strong dependence on the star formation rate, to the extent that a three dimensional fundamental metallicity relation exists which links the three parameters with minimal scatter. In this work, we use a sample of 4253 lo cal galaxies observed in atomic hydrogen from the ALFALFA survey to demonstrate, for the first time, that a similar fundamental relation (the Hi-FMR) also exists between stellar mass, gas-phase metallicity, and Hi mass. This latter relation is likely more fundamental, driving the relation between metallicity, SFR and mass. At intermediate masses, the behaviour of the gas fundamental metallicity relation is very similar to that expressed via the star formation rate. However, we find that the dependence of metallicity on Hi content persists to the highest stellar masses, in contrast to the saturation of metallicity with SFR. It is interesting to note that the dispersion of the relation is very low at intermediate stellar masses (9 < log (M*) < 11), suggesting that in this range galaxies evolve smo othy, in an equilibrium between gas inflow, outflow and star formation. At high and low stellar masses, the scatter of the relation is significantly higher, suggesting that merging events and/or sto chastic accretion and star formation may drive galaxies outside the relation. We also assemble a sample of galaxies observed in CO. However, due to a small sample size, strong selection bias, and the influence of a metallicitydependent CO/H2 conversion factor, the data are insufficient to test any influence of molecular gas on metallicity. 10:15-10:30 Maritza Lara-Lopez Email: mlopez@aao.gov.au Title: Galaxy And Mass Assembly (GAMA): The connection between metals, specific-SFR, and HI gas in galaxies: the Z-SSFR relation Abstract: We study the interplay between gas phase metallicity (Z), specific star formation rate (SSFR) and neutral hydrogen gas (HI) for galaxies of different stellar masses. Our study uses spectroscopic data from GAMA and SDSS star forming galaxies, as well as HI-detection from the ALFALFA and GASS 23


public catalogues. We present a mo del based on the Z-SSFR relation that shows that at a given stellar mass, depending on the amount of gas, galaxies will follow opposite behaviours. Low-mass galaxies with a large amount of gas will show high SSFR and low metallicities, while low-mass galaxies with small amounts of gas will show lower SSFR and high metallicities. In contrast, massive galaxies with a large amount of gas will show mo derate SSFR and high metallicities, while massive galaxies with small amounts of gas will show low SSFR and low metallicities. Using ALFALFA and GASS counterparts, we find that the amount of gas is related to those drastic differences in Z and SSFR for galaxies of a similar stellar mass. 11:00-11:30 Jacqueline Ho dge Email: ho dge@mpia.de Title: Gas at high-redshift: Beyond detection Abstract: Molecular gas, as the fuel for star formation, is intimately linked to the formation and evolution of galaxies and a key observable in studies of high-redshift star formation. It has been detected in over a hundred high-redshift galaxies, from FIR-luminous quasars and submillimeter galaxies to more 'normal' star forming galaxies on the main sequence. Beyond simple detections, we are now moving into the era of more complex observations, including resolved imaging and galaxy dynamics, spectral line scans, and molecular deep fields. I will discuss progress in this area, highlighting recent results from current centimeter/(sub-)millimeter interferometers and touching on future prospects with the full ALMA. 11:30-11:45 Mark Sargent Email: mark.sargent@cea.fr Title: A direct estimate of the molecular gas history of the Universe through CO luminosity functions and H2 mass function evolution Abstract: The observations of the past several years revealed the existence of a so-called "main sequence" for star-forming galaxies out to high redshift. While the ma jority of star-forming galaxies obeys this fairly tight relation between star formation rate (SFR) and stellar mass, a smaller subset of the population - referred to as "starbursts" - displays specific star-formation rates and star formation efficiencies (SFE) that can exceed those of normal (main-sequence) galaxies by an order of magnitude. The current interpretation of the CO-line emission from the roughly 90 normal star-forming galaxies detected to date at z>0 suggests that there is a high degree of homogeneity between low- and high-redshift main-sequence galaxies in terms of their molecular gas properties. I will show that the variations of SFE and gas fraction about the characteristic value of an average main sequence galaxy do not change over the range z < 3. The change in SFE for galaxies undergoing a starburst scales supralinearly with the SFR enhancement, as expected for merging events, implying a continuous distribution of galaxies in the Schmidt-Kennicutt plane that is not strictly bimo dal, but nevertheless more clearly separated into a lo cus for starbursts and normal galaxies than their relative distribution in the space of SFR and stellar mass. I will discuss how we can exploit these scaling relations to infer the molecular gas properties (e.g. H2 mass functions and CO-luminosity functions) of the large samples of distant star-forming galaxies that await detection in upcoming blind sub-mm surveys with ALMA and the JVLA. I will also apply our formalism for distinguishing between starburst and normal galaxies (successfully used to split IR luminosity functions at 0

activity, respectively. 11:45-12:00 Bitten Gullberg Email: bgullber@eso.org Title: [CI I] and CO ladders in lensed SMGs from the SPT survey Abstract: ALMA spectroscopy of point sources from the South Pole Telescope (SPT) survey has uncovered a population of high-redshift (z=2-5.7), strongly lensed submillimetre galaxies (SMGs). Using APEX/FLASH and Herschel SPIRE FTS, we are doing a follow-up survey of the [CII] fine structure line, the most important co oling line for atomic gas. These 18 sources represent the first homogeneously selected [CII] survey, with thus far detections in 77In addition, ALMA (Cycle 0 and 1), ATCA and APEX follow-up allow us to observe the CO ladder in a significant subset of our targets. In this talk I will present our [CII] data and link the fine structure and molecular lines (CO) using a L[C I I ] /LF I R vs. LC O(1-0) /LF I R diagnostic plot. This plot shows a tentative evolution of the physical parameters from z4 to z5.7. I will also present the first result from mo delling of the physical parameters for the molecular gas in five of our sources. This is the start of the first systematic study of the properties of the ISM for a sample of statistical and uniformly selected sources. 12:00-12:15 TBD 12:15-12:30 Susie Alaghband-Zadeh Email: sa543@ast.cam.ac.uk Title: Using [CI] to probe the Interstellar Medium in z2.5 Sub-Millimeter Galaxies Abstract: High-z ULIRGs, identified by their emission at submm wavelengths (SMGs), are found to have some of the highest star formation rates (SFRs) in the Universe. These extreme systems are often found to have multiple interacting components, suggesting the intense star formation is triggered by mergers as in lo cal ULIRGs. However there is significant evidence to suggest that the high-z ULIRGs are not simply scaled-up versions of those found lo cally. I will present new [CI](1-0) and CO(4-3) IRAM-PdBI observations of SMGs at z2.5, comparing the observed line ratios to the outputs of photo disso ciation region (PDR) mo dels to constrain the physical conditions in the ISM of the SMGs. I find that the SMGs are most comparable to lo cal ULIRGs in radiation field and density, however a significant tail of the SMGs are likely best compared to less compact, lo cal starburst galaxies, providing new evidence that many SMGs have extended star formation distributions and are therefore not scaled up versions of the compact lo cal ULIRGs. I also explore the use of [CI] as a tracer of the H2 gas finding that the masses derived from the [CI] observations are consistent with the H2 gas masses determined from the CO observations, suggesting that [CI] provides a useful to ol to probe the bulk gas and the therefore complicated gas pro cesses o ccurring within these violent merging systems. The high SFRs and the large reservoirs of gas available to act as fuel for the star formation imply that SMGs can build up stellar mass very quickly and are therefore interpreted to be the progenitors of the massive elliptical galaxies observed in the lo cal universe. Constraining the H2 gas masses along with the conditions within the ISM of the SMGs is thus vital to understand the origin of the inGo erdtense star formation and therefore also their evolution towards present day galaxies. 13:40-13:55 25


Tobias Go erdt Email: tobias.go erdt@uam.es Title: Cold streams: detectability and characteristics Abstract: Cold gas streaming along the dark-matter filaments of the cosmic web is predicted to be the ma jor provider of resources for disc buildup, violent disk instability and star formation in massive galaxies in the early universe. We use high-resolution cosmological hydro dynamical adaptive mesh refinement (AMR) simulations to study to what extent these cold streams are traceable in the extended circum-galactic environment of galaxies via Ly alpha emission, Ly alpha absorption and selected low ionisation metal absorption lines. We predict the strength of the absorption signal and find that the Ly alpha absorption profiles pro duced by the streams are consistent with observations of absorption Ly alpha profiles in high redshift galaxies. Due to the low metallicities in the streams, and their low covering factors, the metal absorption features are weak and difficult to detect. The characteristics of the Ly alpha emission of our simulated Ly alpha blobs (LABs) are similar in luminosity, morphology and extent to the observed LABs, with distinct kinematic features. The predicted Ly alpha luminosity function is consistent with observations, and the predicted areas and linewidths roughly recover the observed scaling relations. This mechanism for pro ducing LABs appears inevitable in many high-z galaxies. Some of the LABs may thus be regarded as direct detections of cold streams. We analyse the characteristics of the cold streams in simulations and present scaling relations for the amount of infall, its velo city, distribution and its clumpiness and compare our findings with observations. 13:55-14:10 Dominik Bomans Email: bomans@astro.rub.de Title: Mapping galactic outflows in emission and absorption Abstract: Galactic outflows and winds are key ingredients for the birth and live of galaxies in the intergalactic medium. Via outflows the halos of galaxies are structured, heated and enriched with heavy elements. Using integral field spectroscopy data (especially from the CALIFA survey) we will explore the properties and frequency of outflows/winds based on a large, complete sample of intermediate and high mass galaxies in the lo cal universe. Additional observational information for the low mass end (using Fabry-Perot 2d-spectro copy) and the the high mass end of galaxies (using long-slit spectroscopy) will be presented to further explore the parameter space for the o ccurance and properties of outflows and winds, and therefore the resulting sphere of influence of these galactic feedback pro cesses. 14:10-14:25 Lindley Lentati Email: ltl21@cam.ac.uk Title: Early results from an unbiased JVLA deep field survey of cold molecular gas in COSMOS Abstract: With the huge increase in spectral line and continuum sensitivity of new submm through cm-wavelength interferometers like ALMA and the JVLA, we are entering a new era in blind surveys of obscured star-forming galaxies at high-redshift. The significant frequency coverage of these instruments means that large volumes can be searched for molecular and atomic emission lines like CO or [CII] in order to obtain unbiased contraints on the evolution of star-forming gas in the Universe. Such surveys require techniques which can efficiently identify emission lines in large spectral line data cubes. In this talk, I will present a Bayesian approach to this problem and show how it has been successfully applied to a deep 3mm-wavelength PdBI spectral line survey of the Hubble Deep Field North. I will also show preliminary results of a new JVLA survey of the COSMOS field which simultaneously surveys CO J=1-0 26


over the redshift range, 2.0 < z < 2.8, around the peak of obscured galaxy formation and AGN activity at high-redshift. 14:25-14:40 Roberto Decarli Email: decarli@mpia.de Title: The forbidden side of the high-redshift universe Abstract: The study of the properties of the interstellar medium in high-z (z>3) galaxies is hindered by the fact that most of the relevant diagnostics are based on rest-frame emission lines which are shifted in the mid-IR bands, where sensitive spectroscopy is out of reach for present-day instrumentation. A new way to overcome this limitation is offered by fine-structure forbidden emission lines of the same ISM tracers (neutral and ionized oxygen and carbon, ionized nitrogen). These lines enter the (sub-)mm transparent windows of the atmosphere when redshifted beyond z3, and are now detectable thanks to substantial upgrades in the available facilities (e.g., JVLA and PdBI) and to the advent of the ALMA. I will report on 1) the first survey of [NII]205um in high-z galaxies; 2) the detection of [CII]158um in the most distant quasar (z7.1) and in one of the most distant sub-mm galaxies (z5.2); 3) sensitive upper limits on the [CII]158um emission in some Ly-alpha emitters at z>6. These measurements represent a fundamental step in our understanding of the properties (ionization states, densities, temperature, abundances) of star-forming gas in high redshift galaxies. 14:40-15:05 John Peaco ck Conference Summary 14:05-15:15 Paul Alexander closing remarks 15:15-15:20 Malcolm Longair The final word

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