Australia Telescope National Facility
Annual Student Symposium 2000
Wednesday 26th of April
Marsfield Lecture Theater
Program:

10:30     WELCOME
10:35     Matthew Howlett:                 Source Detection with Wavelet Analysis
11:00     Jasmina Lazendic:                  Molecular Shocks from the Supernova Remnants
11:25     Tracy Getts:                           Radio Emission from ``Non-Spectacular'' Interacting Galaxies
11:50     Hayley Bignall:                      What's Special about IDV Blazars?
12:15     LUNCH
1:30       Vivienne Wheaton:                Investigation of Radio Emission from SNR 1987a
1:55       Erik Muller:                            HI Observations of the Magellanic Bridge
2:20       Melanie Johnston-Hollitt:    Emission Processes in Clusters of Galaxies
2:45       AFTERNOON TEA
3:15       Dave Rayner:                         Circular Polarization of... Something Different!
3:40                                                       Discussion & Feedback
4:00     CLOSE


Abstracts
 

Matthew Howlett    Source Detection with Wavelet Analysis

I have investigated using the discrete, à trous and continuous wavelet transforms to automatically detect galaxies in the HIPASS image cubes.  I will review each of these transforms and describe the advantages and disadvantages of each for the purpose of source detection.

Jasmina Lazendic    Molecular Shocks from the Supernova Remnants

Interactions between supernova remnants and the surrounding molecular clouds are commonly expected, yet there have been little observational evidence.  1720-MHz OH maser emission unaccompanied with masing of other three OH lines has been recently identified as a sign-post of such a reactions.  It is believed that such an emission arise from gas shocked by the impact of the expanding SNR into the molecular material.  To examine this model and to obtain insights into the effect of shocks on the interstellar medium, we are carrying out millimetre and IR observations of selected objects associated with 1720-MHz OH masers.

Tracy Getts      Radio Emission from ``Non-Spectacular'' Interacting Galaxies

I have undertaken a radio (HI and Associated Radio Continuum) study of 5 interacting systems of galaxies.  Normally one associates with interacting galaxies phenomena such as gaseous tails and bridges, prolific star formation and disrupted dynamics.  These 5 systems were chosen because they are optically "non-spectacular", and while HI results show gaseous tails and bridges in several cases and atomic gas at large radii, other phenomena normally associated with interacting/merging galaxies such as star-bursting and circumnuclear disks or rings (to name a couple) are not observed.  Several systems also show large continuum halos which are uncommon.

Hayley Bignall    What's special about IDV blazars?

My PhD project has involved monitoring a sample of blazars, selected for X-ray observations, with the ATCA. Many of these sources are highly variable on timescales of weeks to months.  The sample includes 3 sources which show substantial variability on timescales of around 1 day.  This raises the question, "what makes these sources special, compared to other, non-IDV blazars?"  I will present some results from ATCA observations and discuss some of the questions we hope to answer with regard to IDV.

Vivienne Wheaton    Investigation of Radio Emission from SNR 1987a

The interaction between the ejecta from Supernova 1987A and surrounding material is producing steadily brightening radio emission.  I present recent observations of SNR 1987a from the ongoing monitoring program at the ATCA, including light curves from July 1990 to the present and a sequence of super-resolved images of the remnant.  Interpretation of features of the light curves, the spectrum evolution and the images will be discussed.

Erik Muller    HI Observations of the Magellanic Bridge

21cm line emission has been observed from a 6x7 degree area of the Magellanic Bridge east of the Small Magellanic Cloud with the Australia Telescope Compact Array and with the Parkes dish.  We present here the resulting data cube spanning a velocity range from 100km/sec to approximately 350km/sec.  The structure of the neutral Hydrogen of this region is seen to be rich and complex, with many bubbles, filaments and shells apparent.  Some preliminary statistics of shell diameters and expansion velocities is presented and shell positions are compared to that of catalogued young stellar associations occurring in the area.

Melanie Johnston-Hollitt    Emission Processes in Clusters of Galaxies

My research centers on a sample of rich, x-ray luminous, southern clusters of galaxies that I am studying in the radio to obtain information on their physical properties.  As rich, x-ray, luminous clusters these objects produce emission across the electromagnetic spectrum which can be utilized as a tool to understanding key points of cluster evolution. I will discuss the processes which give rise to the emission at various wavelengths in relation to the most interesting cluster A3667 and explain how multiwavelength observations are required to understand the whole picture.

Dave Rayner    Circular polarization of... something different!

Radio-jet X-ray binary systems are often considered "mini-quasars", and are the nearest objects in which the physics of relativistic jets can be studied.  I'll discuss the recently published detection of circular polarization in the famous X-ray binary SS 433, and present some even more recent results which use a new calibration standard.


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