Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.atnf.csiro.au/research/conferences/student_symposia/ASS2005/programme.ps Äàòà èçìåíåíèÿ: Fri May 6 02:52:54 2005 Äàòà èíäåêñèðîâàíèÿ: Wed Dec 26 12:56:51 2007 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: sculptor galaxy

ATNF
Student Symposium 2005
Wednesday May 11
9:25am Welcome
9:30am First Session Chair: Rachel Deacon
9:30am Deanna Matthews The Structure of the Magellanic Stream: Pilot Survey and Results
9:50am Katherine Newton­McGee Depolarisation Silhouettes and Faraday Mapping
10:10am Emil Lenc Seeing the Bigger Picture
10:30am Adam Deller Software correlation for advanced VLBI,
with applications in pulsar and extragalactic astrophysics
10:50am Aaron Chippendale The Cosmological Reionization Experiment
11:00am Co#ee
11:30am Second Session: Pulsars Chair: Katherine Newton­McGee
11:30am Aidan Hotan High Precision Baseband observations of binary and millisecond pulsars
12:00am Haydon Knight Giant Pulses from the millisecond pulsar J0218+4232
12:20pm Natasa Vranesevic What is special about high­B pulsars?
12:50pm Lunch

13:50pm Third Session: Extragalactic Chair: TBA
13:50pm Antoine Bouchard HI detection of early­type dwarf galaxies in the Sculptor Group
14:10pm Leith Godfrey A multi­wavelength study of X­ray bright extragalactic jets
14:30pm Vicky Safouris Giant Radio Galaxies and the IGM
14:50pm Close

Abstracts
Deanna Matthews, LaTrobe University
The Structure of the Magellanic Stream: Pilot Survey and Results
The HI structure of the Magellanic Stream has proved useful in studying the gravitational and ram­
pressure interaction of the Magellanic Clouds with the Galaxy, and for investigating the orbital history
of the SMC and LMC. Previous Parkes observations reveal several tantalising features such as a residual
helicity and transverse velocity gradient which might reflect the binary motion of the SMC and LMC
and instabilities in fluid flow from the SMC into the stream, which might represent interaction with the
hot halo gas. A 200 deg region at the head of the stream was observed in October 2003, and will again
be observed in July 2004. The results obtained thus far will be discussed, as will the need for further
observations.
Katherine Newton­McGee, University of Sydney
Depolarisation Silhouettes and Faraday Mapping
Magnetic fields play a major role in many important processes, sucha as turbulence and gas motions,
conduction and heating in gas clouds of the interstellar medium (ISM) and in cloud collapse and star
formation. There are many methods by which to study both small and large scale magnetic fields in the
nearby universe, however Faraday rotation is currently the only technique that allows magentic fields of
distant objects to be studied in detail. We present the plans to study the magnetic fields of distant galax­
ies and also examine how Faraday roation can be used to probe the magneto­ionic ISM of our own Galaxy.
Emil Lenc, Swinburne University
Seeing the bigger picture
VLBI imaging in the past, due to constraints in data storage capacity and processing time, were limited
to relatively narrow fields of view. With recent technological improvements and the implementation of
new imaging algorithms it is now feasible to fully utilize the high resolution capabilities of VLBI over
a wide­field of view. I will briefly talk about my application of wide­field VLBI techniques to starburst
galaxies and AGN jets.
Adam Deller, Swinburne University
Software correlation for advanced VLBI,
with applications in pulsar and extragalactic astrophysics
Both pulsars and extragalactic supernova remnants are (even for radio astronomy) com­
paratively weak sources, requiring extremely sensitive interferometers to detect and image
them. The software correlator will allow high data rate (up to 1 Gbps) VLBI observations
to be processed, providing high sensitivity and high spectral resolution data sets for the
detailed study of weak celestial radio sources and masers. In this talk, I will discuss the
implementation of the software correlator, its immediate benefits and application and its
role in eVLBI and SKA research.

Aaron Chippendale, ATNF
The Cosmological Reionization Experiment
First light for the ATNF Cosmological Reionization Experiment is scheduled for June this
year. Our goal is to measure the VHF background sky spectrum with 1 mK accuracy. We
have designed a receiver and spectrometer covering the 114­228 MHz band, corresponding
to HI redshifts of 11.5­5.2. We will observe with both one and two antennas, yielding both
total power and interferometric measurements of low spatial resolution. I will present the
design philosophy, the observing strategy and a the current status.
Aidan Hotan, Swinburne University
High Precision Baseband observations of binary and millisecond pulsars
In August 2002, a new pulsar recording system known as CPSR2 was brought on­line
at the Parkes radio telescope. This instrument utilises a technique known as ''coherent
dedispersion'' that allows unprecedented precision in measurements of pulse arrival times
and mean profile polarimetry. In this talk I describe highlights of the results obtained
during the first two years of operation. These include precision timing of a supposedly
unstable pulsar and the detection of a General Relativistic e#ect known as geodetic pre­
cession in the binary pulsar J1141­6545. I will also describe observations of the primary
component of the double pulsar binary system, PSR J0737­3039A, taken in May 2004.
From this data set, we obtain calibrated mean polarimetric profiles and detect the signa­
ture of General Relativistic Shapiro delay, which can be used to constrain the inclination
angle of the binary system.
Haydon Knight, Swinburne University
Giant Pulses from the millisecond pulsar J0218+4232
We have conducted a search for giant pulses from three millisecond pulsars using the
Greenbank telescope. PSR J0218+4232 was found to emit giant pulses of very short in­
trinsic durations at both 857 and 1373 MHz. Only 3 of the 151 pulses found had energies
greater than 10 times the average pulse energy. The pulses coincide with the minima of
the integrated emission profile and follow a power­law energy distribution. We suggest
that the 'giant pulse' emission phenomenom be defined as nanosecond­timescale emissions
with power­law energy distributions rather than pulses of high energy. The non­detection
of emission from PSRs B1957+20 and J1843­1113 confirms that the existence of pulsed
X­ray emission with a hard spectrum is a better indicator of giant pulse emissivity than
high magnetic field at the light cylinder.
Natasa Vranesevic, Sydney University
What is special about high­B pulsars

The Parkes multibeam survey led to the identification of a number of long­period pulsars
with magnetic field well above the ``quantum critical field'' of 4.4 x 10 to 13 G. Traditional
pulsar emission theories postulated that radio emission is suppressed above the this criti­
cal field. The aims of this project is to understand emission properties of high­B pulsars.
So in this talk I will give brief introduction to the topic with highlights to the pulsar
characteristics which we plan to study in order to attain radio emission characteristic for
high magnetic field pulsars
Antoine Bouchard, Australian National University
HI detection of early­type dwarf galaxies in the Sculptor Group
We present deep HI Parkes observations of 5 lowest luminosity galaxies of the Sculptor
Group. These high spectral resolution observations are significantly deeper than any pre­
vious detection attempts. Of the 5 targets, 4 were detected, leaving a single Sculptor
group galaxy, Scl­dE1, without any HI detections (MHI /LB < 0.01). ATCA archived
data shows significant o#sets between the HI and optical components
Leith Godfrey, Australian National University
A Multi­wavelength study of X­ray bright Extragalactic Jets
Observations with the Chandra X­ray Observatory have recently shown that quasars and
radio galaxies often exhibit bright X­ray emission from the associated jets. As part of my
thesis I will be investigating the relationship between the radio and X­ray emission from
a sample of quasars with prominent X­ray jets.
In this talk I will share some initial results from our ATCA 12mm imaging performed
last year. I will also discuss the upcoming ATCA and LBA observations of a particularly
unusual quasar jet (PKS 1421­490) that will help to reveal the nature of this source.
Vicky Safouris, Australian National University
Giant radio galaxies and the IGM
I will present new ATCA mosaic observations of the extended structure of the giant
radio galaxy 0319­454 where we believe local gradients in the IGM are responsible for
the unusual appearance of the radio lobes. Galaxy redshifts in the vicinity of the giant
radio source have been measured with the 2dF instrument on the AAT and show that the
host galaxy is located at the edge of a filament in the galaxy distribution with the radio
axis parallel to the filament. I will briefly discuss future plans for modeling the physical
interaction between the light synchrotron plasma and di#use warm­hot gas associated
with the galaxy filament.