Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://lnfm1.sai.msu.ru/~rastor/Books/Brodie&Strader_ARAA-ExtragalGC.pdf Äàòà èçìåíåíèÿ: Tue May 11 14:36:56 2010 Äàòà èíäåêñèðîâàíèÿ: Mon Oct 1 23:06:53 2012 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: asterism

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Extragalactic Globular Clusters and Galaxy Formation
Jean P. Brodie and Jay Strader
UCO/Lick Observatory, University of California, Santa Cruz, CA 95064; email: brodie@ucolick.org, strader@ucolick.org

Annu. Rev. Astron. Astrophys. 2006. 44:193­267 First published online as a Review in Advance on June 5, 2006 The Annual Review of Astrophysics is online at astro.annualreviews.org doi: 10.1146/ annurev.astro.44.051905.092441 Copyright c 2006 by Annual Reviews. All rights reserved 0066-4146/06/09220193$20.00

Key Words
galaxy evolution, globular clusters, star clusters, stellar populations

Abstract
Globular cluster (GC) systems have now been studied in galaxies ranging from dwarfs to giants and spanning the full Hubble sequence of morphological types. Imaging and spectroscopy with the Hubble Space Telescope and large ground-based telescopes have together established that most galaxies have bimodal color distributions that reflect two subpopulations of old GCs: metal-poor and metal-rich. The characteristics of both subpopulations are correlated with those of their parent galaxies. We argue that metal-poor GCs formed in low-mass dark matter halos in the early universe and that their properties reflect biased galaxy assembly. The metal-rich GCs were born in the subsequent dissipational buildup of their parent galaxies and their ages and abundances indicate that most massive early-type galaxies formed the bulk of their stars at early times. Detailed studies of both subpopulations offer some of the strongest constraints on hierarchical galaxy formation that can be obtained in the near-field.

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1. INTRODUCTION
Globular star clusters (GCs) are among the oldest radiant objects in the universe. With typical masses 104 ­106 M (corresponding to luminosities of MV = -5 to -10) and compact sizes (half-light radii of a few parsecs), they are readily observable in external galaxies. The 15 years since the Annual Review by Harris (1991, "Globular Cluster Systems in Galaxies Beyond the Local Group") have seen a revolution in the field of extragalactic GCs. It is becoming increasingly apparent that GCs provide uniquely powerful diagnostics of fundamental parameters in a wide range of astrophysical processes. Observations of GCs are being used to constrain the star formation and assembly histories of galaxies, nucleosynthetic processes governing chemical evolution, the epoch and homogeneity of cosmic reionization, the role of dark matter in the formation of structure in the early universe, and the distribution of dark matter in present-day galaxies. GCs are valuable tools for theoretical and observational astronomy across a wide range of disciplines from cosmology to stellar spectroscopy. It is not yet widely recognized outside the GC community that recent advances in GC research provide important constraints on galaxy formation that are complementary to in situ studies of galaxies at medium-to-high redshift. The theme of this review is the role of GC systems as tracers of galaxy formation and assembly, and one of our primary aims is to emphasize the current and potential links with results from galaxy surveys at high redshift and interpretations from stellar population synthesis, numerical simulations, and semianalytical modeling. In what follows we will attempt to chronicle the observations that mark recent milestones of achievement and place them in the wider theoretical and observational context. We will focus most closely on work carried out since about 2000. The preceding period is well-covered by the book of Ashman & Zepf (1998) and the Saas-Fee lectures of Harris (2001).1 Among the significant topics not directly covered are young massive clusters (potential "protoGCs"), X-ray sources in extragalactic GCs, and ultra-compact dwarf galaxies. Neither do we include a comprehensive discussion of the Galactic GC system. The fundamental premise in what follows is that GCs are good tracers of the star formation histories of spheroids (early-type galaxies, spiral bulges, and halos), in the sense that major star-forming episodes are typically accompanied by significant GC formation. Low-level star formation (e.g., in quiescent galactic disks) tends to produce few, if any, GCs. Because most of the stellar mass in the local universe is in spheroids (75%; Fukugita, Hogan & Peebles 1998), GCs trace the bulk of the star-formation history of the universe. Although the relationships between star formation, GC formation, and GC survival are complex and do not necessarily maintain relative proportions under all conditions, this underlying assumption is supported by a number of lines of argument. Massive star clusters appear to form during all major star-forming events, such as those accompanying galaxy-galaxy interactions (e.g., Schweizer 2001). In these situations, the number of new clusters formed scales with the amount of gas involved in the interaction (e.g., Kissler-Patig, Forbes & Minniti
1

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Available online at http://physwww.mcmaster.ca/harris/Publications/saasfee.ps.

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1998). The cluster formation efficiency (the fraction of star formation in clusters) scales with the star-formation rate, at least in spiral galaxies where it can be directly measured at the present epoch (Larsen & Richtler 2000). This may suggest that massive clusters form whenever the star-formation rate is high enough, and that this occurs principally during spheroid formation. Perhaps most importantly, the properties of GCs (especially their metallicities) are correlated with the properties of their host galaxies.

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2. COLOR BIMODALITY: GLOBULAR CLUSTER SUBPOPULATIONS
Perhaps the most significant development of the decade in the field of extragalactic GCs was the discovery that the color distributions of GC systems are typically bimodal. Indeed, color bimodality is the basic paradigm of modern GC studies. Nearly every massive galaxy studied to date with sufficiently accurate photometry has been shown to have a bimodal GC color distribution, indicating two subpopulations of GCs. In principle, these color differences can be due to age or metallicity differences or some combination of the two. Due to the well-known degeneracy between age and metallicity (e.g., Worthey 1994), the cause of this bimodality is not readily deduced from optical colors alone. Nonetheless, the significance of the finding was immediately recognized. The presence of bimodality indicates that there have been at least two major star-forming epochs (or mechanisms) in the histories of most--and possibly all--massive galaxies. Subsequent spectroscopic studies (see Section 4) have shown that color bimodality is due principally to a metallicity difference between two old subpopulations. With our "bimodality-trained" modern eyes, we can see evidence of the phenomenon in the B - I CFHT imaging of NGC 4472 in Couture, Harris & Allwright (1991) and C - T1 CTIO imaging of NGC 5128 by Harris et al. (1992). However, the first groups to propose bimodality (or "multimodality") were Zepf & Ashman (1993) for NGC 4472 and NGC 5128 and Ostrov, Geisler & Forte (1993) for NGC 1399 (in fact, using the Harris and colleagues and Couture and colleagues colors). Observations of the GC systems of galaxies throughout the 1990s provided mounting evidence that bimodality was ubiquitous in massive galaxies. The primary catalyst of this research was the advent of the Hubble Space Telescope (HST). The Wide Field and Planetary Camera 2 (WFPC2) provided the spatial resolution and accurate photometry needed to reliably identify GC candidates in galaxies as distant as the Virgo Cluster at 17 Mpc (e.g., Whitmore et al. 1995). At this distance, GCs (with typical half-light radii of 2­3 pc 0.03­0.04 ) are resolvable with the HST and their sizes are measurable with careful modeling of the point spread function. This drove down the contamination from background galaxies and foreground stars to low levels and was a substantial improvement over multiband optical photometry from the ground. Among the larger and more comprehensive photometric studies using HST/WFPC2 were Gebhardt & Kissler-Patig (1999), Larsen et al. (2001) and Kundu & Whitmore (2001a). Using data from the HST archive, Gebhardt & Kissler-Patig showed that bimodality was a common phenomenon. However, since the imaging

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was shallow for many of the galaxies in their sample, they failed to find bimodality in 50% of their 50 galaxies. Taking advantage of deeper data, Larsen et al. (2001) and Kundu & Whitmore (2001a) found statistically significant bimodality in most of their sample galaxies, the majority of which were of early-type. Galaxies that were tentatively identified as unimodal in these studies were later, with improved photometric precision, shown to conform to the bimodality "rule." Indeed, it is important to note that no massive elliptical (E) galaxy has been convincingly shown to lack GC subpopulations. An absence of metal-poor GCs was suggested for both NGC 3311 (Secker et al. 1995) and IC 4051 (Woodworth & Harris 2000), and an absence of metal-rich GCs for NGC 4874 (Harris et al. 2000). However, HST/WFPC2 imaging of NGC 3311 (Brodie, Larsen & Kissler-Patig 2000) revealed a healthy subpopulation of metal-poor GCs. It is now clear that the WFPC2 photometry of the Coma E IC 4051 was not deep enough to securely argue for a uni- or bimodal fit. Finally, the NGC 4874 result was due to a photometric zeropoint error (W. Harris, private communication). The discovery of a massive E that indeed lacked a metal-poor (or metal-rich) subpopulation would be important, but so far no such instances have been confirmed. The majority of these HST studies were carried out in V - and I -equivalent bands. This choice was largely driven by efficiency considerations [shorter exposure times needed to reach a nominal signal-to-noise (S/N)], despite the fact that other colors, such as B - I , offer much better metallicity sensitivity for old stellar populations. It has been known for some time that the GC system of the Milky Way is also bimodal. The presence of GC subpopulations in the Milky Way was codified by Zinn (1985; see also Armandroff & Zinn 1988) who identified two groups of GCs. "Halo" GCs are metal-poor, nonrotating (as a system), and can be found at large galactocentric radii. "Disk" GCs are metal-rich and form a flattened, rotating population. Later work on the spatial and kinematic properties of the metal-rich GCs by Minniti (1995) ^´ and Cote (1999) identified them with the Milky Way bulge rather than its disk (as we shall see below, this association seems to hold for other spirals as well, although see the discussion in Section 3.3). In addition to their sample of early-type galaxies, Larsen et al. (2001) also discussed the GC systems of the Milky Way and NGC 4594 in some detail, pointing out that the locations of the GC color peaks in these spirals were indistinguishable from those of massive early-type galaxies. The blue (metal-poor) and red (metal-rich) peaks in massive early-type galaxies typically occur at V - I = 0.95 ± 0.02 and 1.18 ± 0.04 (Larsen et al. 2001). These colors correspond to [Fe/H] -1.5 and -0.5 for old GCs (or a bit more metal-rich, depending on the metallicity scale and color-metallicity relation adopted). Figure 1 shows a histogram of the V - I colors of GCs in the Virgo gE M87, which clearly shows bimodality (Larsen et al. 2001). However, the peak locations are not exactly the same for all galaxies. Before GC bimodality was discovered, van den Bergh (1975) suggested and Brodie & Huchra (1991) confirmed a correlation between the mean color/metallicity of GC systems and the luminosity of their parent galaxies. Brodie & Huchra (1991) also showed that the slope of this relation was very similar to the relation connecting galaxy color and galaxy luminosity, but the GC relation was offset toward lower metallicities by about 0.5 dex. They noted that the similarity in

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100

N
50

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0

0.8

1.0

1.2

1.4

V- I (mag)
Figure 1 V - I color histogram of globular clusters in the Virgo giant elliptical M87, showing clear bimodality (Larsen et al. 2001; figure from data courtesy of S. Larsen).

slope suggests a close connection between the physical processes responsible for the formation of both GCs and galaxies. Subsequently, a correlation between the color of just the metal-rich GCs and host galaxy luminosity was found by Forbes, Brodie & Grillmair (1997), Larsen et al. (2001), and Forbes & Forte (2001). The slope of this relation was again found to be similar to that of the color-magnitude relation for early-type galaxies (V - I -0.018 MV ), suggesting that metal-rich GCs formed along with the bulk of the field stars in their parent galaxies. With the exception of Larsen et al. (2001), little or no correlation between the color of the metal-poor GCs and host galaxy luminosity was reported in these studies, although Burgarella, Kissler-Patig & Buat (2001) and Lotz, Miller & Ferguson (2004) suggested such a relation might be present, but only for the dwarf galaxies. Larsen and colleagues found a shallow relation for the metal-poor GCs in their sample of 17 massive early-type galaxies, albeit at moderate (3 ) statistical significance. Strader, Brodie & Forbes (2004b) compiled and reanalyzed high-quality data from the literature and found a significant (>5 ) correlation for metal-poor GCs, extending from massive Es to dwarfs over 10 magnitudes in galaxy luminosity. The relation is indeed relatively shallow (V - I -0.009 MV , or Z L0.15 ), making it difficult to detect, especially in heterogeneous data sets. This same slope was confirmed by J. Strader, J.P. Brodie, L. Spitler & M.A. Beasley (submitted) and Peng et al. (2006a) for early-type galaxies in Virgo. Figure 2 shows [Fe/H] versus MB for both subpopulations; the GC peaks are taken from Strader, Brodie & Forbes (2004b) and J. Strader, J.P. Brodie, L. Spitler & M.A. Beasley (submitted) and have been converted from V - I and g - z using the relations of Barmby et al. (2000) and Peng et al. (2006a), respectively. These data, together with ancillary information about the GC systems, are compiled in Table 1. The true scatter at fixed MB is unclear, because the observational errors vary among galaxies, and there may be an additional component due to small differences between

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0 Core E Power-law E S0 Spiral dE dIrr

- 0.5

[Fe/ H] (dex)

-1

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- 1.5

-2

- 12

- 14

- 16

- 18

- 20

- 22

M B (mag)
Figure 2 Peak globular cluster (GC) metallicity versus galaxy luminosity ( MB ) for metal-poor and metal-rich GCs in a range of galaxies. The points are from Strader et al. (2004b) and J. Strader, J.P. Brodie, L. Spitler & M.A. Beasley (submitted) and have been converted from V - I and g - z to [Fe/H] using the relations of Barmby et al. (2000) and Peng et al. (2006a), respectively. Galaxy types are indicated in the figure key; classifications are in Table 1. Linear relations exist for both subpopulations down to the limit of available data.

the V - I and g - z color-metallicity relations. The cutoff in the metal-rich relation at MB -15.5 primarily reflects the magnitude limit of the sample; it may continue to fainter magnitudes, although many such galaxies have only metal-poor GCs. The remarkable inference to be drawn from Figure 2 is that the peak metallicities of both subpopulations are determined primarily by galaxy luminosity (or mass) across the entire spectrum of galaxy types. Using their new color-metallicity transformation between g - z and [Fe/H], Peng and colleagues found Z L0.25 for metal-rich GCs, which is also consistent with the previous estimates of the slope already noted. The color-metallicity relation appears to be quite nonlinear, as discussed below. Thus, even though the slopes of the metal-poor and metal-rich relations are significantly different in the GC color­galaxy luminosity plane, they are similar in the GC metallicity­galaxy luminosity plane (Peng et al. 2006a; see Figure 2). In Section 11 we discuss the constraints on galaxy formation implicit in these relations.

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The Advanced Camera for Surveys (ACS) on HST has significantly advanced our understanding of the color distributions of GC systems, offering a wider field of view and improved photometric accuracy compared to WFPC2. Three large studies of Es utilizing HST/ACS have recently been published. As mentioned above, Peng et al. (2006a) and J. Strader, J.P. Brodie, L. Spitler & M.A. Beasley (submitted) studied the GC systems of early-type galaxies (ranging from dwarf to giant) using g and z data ^ taken as part of the ACS Virgo Cluster Survey (Cote et al. 2004). Peng and colleagues investigated all 100 (E and S0) galaxies, while Strader and colleagues focused solely on the Es. Harris et al. (2006) used BI ACS photometry to analyze GCs in eight "BCGs", galaxies that are among the brightest in their respective groups or clusters. These studies resulted in several new discoveries. First, a correlation was found between color and luminosity for individual metal-poor GCs in some giant Es (the "blue tilt"; see Figure 3). This is the first detection of a mass-metallicity relation for GCs. The blue tilt was found by Strader and colleagues in the Virgo giant Es (gEs) M87 and NGC 4649, and by Harris and colleagues in their sample, although the interpretations of the findings differ. The mass-metallicity relation for individual metal-poor GCs may argue for self-enrichment. Strader and colleagues speculated that these metal-poor GCs were able to self-enrich because they once possessed darkmatter halos that were subsequently stripped (see also discussion in Section 12). The M87 data are well-fit by a relation equivalent to Z M 0.48 over the magnitude range 20 < z < 23.2, where the turnover of the GC luminosity function (GCLF) is at z 23. Harris and colleagues found a similar relation ( Z M0.55 ) but suggested that the trend was only present at bright luminosities ( MI -9.5to -10, corresponding to z 22 in the Strader and colleagues Virgo dataset). The color-magnitude diagrams (CMDs) in Strader and colleagues' research on M87 and NGC 4649 appear consistent with a continuation of the correlation to magnitudes fainter than z = 22, but do not strongly distinguish between the two interpretations. We do know that the blue tilt phenomenon is not confined to galaxies in high density environments or even just to E galaxies. It has recently been reported for NGC 4594 (L. Spitler, J.P. Brodie, S.S. Larsen, J. Strader, D.A. Forbes & M.A. Beasley, submitted), a luminous Sa galaxy that lies in a loose group. Curiously, the Virgo gE NGC 4472 (also studied by Strader and colleagues) shows no evidence for the blue tilt. If this lack of a tilt is confirmed with better data, it will be a strong constraint on any potential "universal" model for explaining the phenomenon in massive galaxies. The Milky Way itself does not show evidence for the tilt, but this could be due to the small number of metal-poor GCs (100) compared to massive galaxies or to the inhomogeneity of metallicities and integrated photometry in current catalogs. Harris and colleagues suggested that the tilted metal-poor GC relation caused the metal-poor and metal-rich peaks to merge at the brightest GC luminosities, turning a bimodal distribution into a nominally unimodal one. By contrast, Strader and colleagues argued that at these high luminosities there is a separate population of objects with larger-than-average sizes and a range of colors, spanning the metal-poor to metal-rich subpopulations. Indeed, Harris and colleagues find that 20­30 of the brightest objects in the nearest galaxy in their sample, NGC 1407 (at 21 Mpc), appear to be extended with respect to normal GCs. The size measurements suggest

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Table 1
d

Properties of GC color distributions
Galaxy Type SN
3.6 ± 0.6 5.1 ± 1.2 ··· 14.1 ± 1.5 ··· 3.5 ± 0.5 4.1 ± 1.0 ··· g-z V-I V-I -0.50 ··· ··· ··· -0.36 -1.44 -1.36 -1.50 -1.59 1.128 1.334 ··· 1.170 ··· 0.912 0.964 0.908 0.942 0.923 -19.9 0.951 1.167 ··· 1.310 ··· 1.164 -1.32 -1.54 -1.43 -1.54 -1.32 -1.56 -1.37 -1.49 -1.38 ··· ··· -0.52 -0.63 -0.31 ··· -0.45 ··· -0.47 ··· -0.35 ··· -0.48 g-z V-I V-I V-I g-z V-I V-I V-I V-I g-z V-I V-I V-I V-I V-I g-z V-I V-I 1.6 ± 0.3 ··· 2.1 ± 0.3 ··· ··· ··· ··· ··· 5.7 ± 1.8 ··· ··· ··· ··· ··· 2 ± 0.5 1.3 1.2 ± 0.3 ··· ··· ··· ··· 1 2 ··· 3 ··· 1 4 ··· 5 ··· 1 ··· ··· ··· ··· ··· 6 ··· ··· ··· ··· ··· 7 8 1 ··· ··· ··· ··· core E core E core(?) E core E core(?) E core E core E S0 core E core(?) E S0/Sa core E core(?) E core(?) E S0 transition E core E core E S0 power E core E Sc core(?) E Sb core E core E power E core E S0 Eridanus G N3607 G Virgo C -20.0 -20.0 N4631 G -20.1 Leo I G -20.1 Local G -20.2 Fornax C -20.3 0.938 Sculptor G -20.3 0.912 Virgo C -20.3 0.951 N4565 G -20.4 0.901 N3115 G -20.4 0.922 1.153 I1459 G -20.6 0.955 ··· N5846 G -20.6 0.935 ··· Virgo C -20.7 0.927 1.305 N2768 G -20.8 0.919 ··· -1.51 -1.45 Pegasus C -20.9 0.920 ··· -1.51 Pegasus C -21.1 0.973 ··· -1.28 Virgo C -21.1 0.891 1.232 -1.63 N4594 G -21.2 0.939 1.184 -1.43 -0.39 N5322 G -21.2 0.942 ··· -1.41 ··· Virgo C -21.2 0.927 1.322 -1.45 -0.33 N524 G -21.4 0.980 1.189 -1.25 -0.37 Virgo C -21.4 0.964 1.424 -1.26 -0.14 g-z V-I Virgo C -21.5 0.986 1.145 -1.23 -0.56 V-I Hydra C -21.5 0.929 ··· -1.47 ··· V-I Virgo C -21.5 0.953 1.390 -1.31 -0.21 g-z Hydra C -21.6 0.947 1.134 -1.39 -0.60 V-I Fornax C -21.8 0.952 1.185 -1.37 -0.39 V-I Virgo C -21.9 0.951 1.411 -1.32 -0.17 g-z
a g

ARI

Name

Environmentb

MB c (mag) Colorf

MP colord (mag) MR color (mag) SN Refs
h

MP [Fe/H]e (dex)

MR [Fe/H]e (dex)

NGC 4472

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NGC 4486

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Brodie

NGC 4406

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NGC 4649

Strader

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NGC 4374

NGC 5322

NGC 4594

NGC 4365

NGC 7619

NGC 7562

NGC 2768

NGC 4621

NGC 5813

IC 1459

NGC 3115

NGC 4494

NGC 4552

NGC 253

NGC 1404

M31

NGC 3379

NGC 4278

NGC 4473

NGC 3608

NGC 1400


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Milky Way S0 core E S0 S0 power E power E power E power E S0 power E S0 Sd power E S0 S0 power E Scd power E Sm dE Sd dE dIrr S0 dE dE dE dE Virgo C Virgo C -17.1 -17.1 Virgo C -17.1 Virgo C -17.2 Leo I G -17.6 Local G -18.0 0.890 0.872 0.864 0.897 0.905 0.884 Virgo C -18.1 0.884 Sculptor G -18.1 0.892 Virgo C -18.1 0.925 Sculptor G -18.3 0.892 ··· 1.130 ··· 1.065 ··· 1.112 1.093 1.168 1.114 1.182 Virgo C -18.4 0.892 1.223 Local G -18.4 0.900 ··· Virgo C -18.5 0.890 1.219 Virgo C -18.5 0.900 1.260 Virgo C -18.6 0.883 1.145 -1.66 -1.58 -1.64 -1.59 -1.63 -1.63 -1.46 -1.63 -1.67 -1.63 -1.71 -1.77 -1.60 -1.56 -1.67 Virgo C -18.6 0.918 1.131 -1.52 Sculptor G -18.7 0.908 ··· -1.56 Virgo C -18.7 0.923 1.320 -1.47 Virgo C -19.0 0.859 1.112 -1.79 -0.72 -0.33 ··· -0.62 -0.56 -0.44 -0.52 ··· -0.51 ··· -0.68 ··· -0.80 ··· -0.70 -0.75 -0.61 -0.71 -0.59 Virgo C -19.0 0.935 1.263 -1.40 -0.44 Leo I G -19.2 0.936 1.103 -1.44 -0.74 Virgo C -19.2 0.911 1.179 -1.53 -0.59 Virgo C -19.2 0.882 1.195 -1.68 -0.56 g-z g-z V-I g-z g-z g-z V-I V-I V-I g-z g-z V-I g-z V-I g-z V-I g-z V-I V-I g-z g-z g-z g-z Fornax C -19.4 0.940 1.153 -1.42 -0.52 V-I N3607 G -19.5 0.939 1.099 -1.43 -0.75 V-I ··· 3.4 ± 0.6 ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· 1.1 ··· 1.6 0.8 ··· 1.8 5.2 0.9 0.7 Leo I G -19.5 0.942 1.208 -1.41 -0.29 V-I ··· N4291 G -19.6 0.940 ··· -1.42 ··· V-I ··· N1023 G -19.7 0.912 1.164 -1.54 -0.48 V-I ···

Sbc

Local G

-19.9 0.898 0.7 8

···

-1.60

···

V-I

NGC 1023

··· ··· ··· ···

NGC 4291

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NGC 3384

NGC 3607

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NGC 1427

9 ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· ··· 10 ··· 10 8 ··· 10 10 10 10 (Continued )

NGC 4478

NGC 4434

NGC 3377

NGC 4564

NGC 4387

NGC 4660

NGC 247

NGC 4733

NGC 4550

NGC 4489

NGC 4551

M33

NGC 4458

NGC 55

IC 3468

NGC 300

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NGC 4482

LMC

201

NGC 3599

IC 3019

IC 3381

IC 3328

NGC 4318


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Table 1
d d

(Continued )
Galaxy Type SN
3.3 0.6 3.7 0.4 5.0 ··· g-z g-z g-z -0.56 ··· -0.61 -0.74 -1.97 -1.74 -2.01 -1.87 -1.92 1.056 N 1.177 1.134 N 0.880 0.898 0.851 0.919 1.060 N N 1.142 -2.33 -2.21 -1.88 -1.82 0.854 -1.69 -1.59 -1.84 -1.49 -0.76 -0.79 -0.79 N -0.82 N -0.60 -0.67 N -0.81 N N -0.66 g-z V-I g-z g-z g-z g-z g-z g-z g-z g-z g-z g-z g-z g-z g-z g-z g-z 5.3 0.8 1.1 1.6 1.2 0.9 0.5 1.2 7.3 1.6 1.0 4.6 0.5 1.0 4.9 4.6 2.0 5.0 0.3 12.1 dE power E dE dE dE power E dE dE dE dE dIrr dE dE dE power E dE dE dE power E power E dE power E dE dE dE dE Virgo C Virgo C -16.0 -15.8 Virgo C -16.0 Virgo C -16.1 Virgo C -16.1 Virgo C -16.1 0.842 Virgo C -16.2 0.779 Virgo C -16.2 0.755 Virgo C -16.2 0.834 Virgo C -16.2 0.845 N Virgo C -16.3 0.818 1.071 Virgo C -16.4 0.869 1.071 Virgo C -16.5 0.824 1.086 Virgo C -16.6 0.931 1.101 -1.42 Virgo C -16.6 0.861 1.169 -1.78 Local G -16.7 0.919 ··· -1.51 Virgo C -16.7 0.848 1.198 -1.85 Virgo C -16.7 0.894 1.042 -1.61 Virgo C -16.8 0.837 1.089 -0.85 -1.91 -0.76 Virgo C -16.8 0.872 1.177 -1.73 -0.60 Virgo C -16.8 0.920 1.126 -1.51 -0.64 Virgo C -16.9 0.938 1.138 -1.39 -0.67 g-z V-I Virgo C -16.9 0.794 N N -2.13 g-z Virgo C -16.9 0.879 1.173 -1.69 -0.60 g-z Virgo C -17.1 0.851 N N -1.84 g-z Virgo C -17.1 0.864 1.129 -1.77 -0.68 g-z
a

Name

Environmentb

MB c (mag) Colorf
g

MP color (mag)

MR color (mag)

MP [Fe/H]e (dex)

MR [Fe/H]e (dex)

SN Refsh
10 10 10

IC 809

28 July 2006

IC 3653

202

IC 3652

14:1

Brodie

VCC 543

10 10 ··· 10 10 10 10 8 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

IC 3470

·

NGC 4486b

Strader

IC 3501

IC 3442

VCC 437

IC 3735

SMC

IC 3032

VCC 200

IC 3487

IC 3509

VCC 1895

IC 3647

IC 3383

VCC 1627

IC 3693

IC 3101

IC 798

IC 3779

IC 3635

VCC 1993

IC 3461


Annu. Rev. Astro. Astrophys. 2006.44:193-267. Downloaded from arjournals.annualreviews.org by Scientific Library of Lomonosov Moscow State University on 05/11/10. For personal use only.

ANRV284-AA44-06

VCC 1886 dE dE dE dE dE dE dE dE dIrr dE dIrr dSph dSph Local G -12.6 0.858 N -1.77 N Local G -12.8 0.871 ··· -1.71 ··· Local G -13.9 0.910 N N -1.55 Local G -14.3 0.807 N N -1.98 Local G -14.7 0.850 ··· -1.80 ··· V-I V-I V-I V-I V-I Local G -14.8 0.882 N N -1.67 V-I Virgo C -15.3 0.838 1.130 -1.90 -0.68 g-z 2.3 4.6 1.2 3.6 1.7 18.1 28.8 Virgo C -15.4 0.858 1.136 7.3 -1.80 -0.67 g-z Virgo C -15.5 0.884 N N 3.3 -1.67 g-z Virgo C -15.6 0.890 1.077 6.3 -1.64 -0.78 g-z Virgo C -15.6 0.898 1.039 9.5 -1.59 -0.87 g-z 10 10 10 10 10 8 11 8 8 11 8 Local G -15.6 0.922 N N 3 8 -1.50 V-I Virgo C -15.7 0.855 N N 1.1 10 -1.82 g-z

dE

Virgo C

-15.8 0.877 N N 1.5 10

-1.70

g-z

IC 3602

ARI

NGC 205

VCC 1539

VCC 1185

28 July 2006

IC 3633

IC 3490

VCC 1661

14:1

NGC 185

NGC 6822

NGC 147

WLM

Sagittarius

Fornax

Power/Core E: Ellipticals with power-law or cored central surface brightness distributions. NGC 4621 is a transition between the two groups. The galaxies with (?) are not formally classified--the division has been made between core/power-law Es at MB = -20 (Faber et al. 1997; J. Kormendy, D.B. Fisher, M.E. Cornell & R. Bender, in preparation). Classifications are from J. Kormendy, D.B. Fisher, M.E. Cornell & R. Bender (in preparation, and private communication) for Virgo galaxies, Faber et al. (1997) for many early-type galaxies, and NED for the remainder. The term dE (dwarf elliptical) is often used for all galaxies that are not star forming with MB > -18 ; here we use it only for galaxies with faint central surface brightness and Sersic n 1 (exponential) profiles. b Local galaxy environment. C: clust