My PhD thesis title is "Neutral Hydrogen in Nearby Galaxy Groups", and I completed the thesis at the University of Melbourne in early 2005, and graduated August 2005. My supervisors were Rachel Webster and David Barnes from the University of Melbourne, DJ Pisano from ATNF, and Michael Drinkwater from the University of Queensland.

The abstract to my thesis:

This thesis describes the creation of the HIPASS groups, the first galaxy group catalogue derived from a blind survey of neutral hydrogen (HI) in the nearby universe. More generally, this thesis also investigates the HI properties of these HIPASS groups, and of compact groups of galaxies, to determine how HI is affected by the group environment.

Observations of the HI in galaxy groups can be used to determine the interaction histories of the member galaxies. In compact groups, where tidal interactions are thought to frequently occur, it is observed that although HI does occasionally appear to be displaced away from the optical galaxy disks by these interactions, the total mass of HI is found to agree with the expected mass in most cases. This finding may suggest that morphological evolution in groups occurs in concert with HI loss, if HI is lost at all.

Loose groups of galaxies, which are less well-defined than compact groups, are found in the HIPASS galaxy catalogue, using the hierarchical group-finding algorithm, and two mass-independent parameters: crossing-time and number density. Due to the low galaxy number density of these groups, galaxy-galaxy interactions between group members are very rare. However it is that galaxies in groups are likely to contain larger quantities of HI than galaxies which are not members of a group. This dependence therefore cannot be the result of interactions between the members, but may be related to previous findings that more luminous galaxies cluster more strongly. It is also found that the morphology-density relation holds for these loose groups.

The star formation rates of galaxies in the HIPASS galaxy catalogue are determined using far-infrared and radio continuum luminosities. It is observed that the total HI mass correlates with the global star formation rate of the galaxies, with a power law index of ~0.79. This index is different to the observed Schmidt law index of ~1.4, which relates star formation surface density to the surface density of gas (including molecular gas). The global star formation rate is also found to be dependent on group membership, with group members having, on average, a lower star formation rate than galaxies in the field. Since galaxy-galaxy interactions are not responsible for this dependence, it may be that processes which occured during the formation of the galaxies depleted the fuel needed to replenish the star formation reservoirs.

My PhD thesis can be downloaded in gzipped Postscript form (7.1MB) by clicking on this link. As an aside, if you like the page style of my thesis, check out my code section, which describes my LaTeX style file.

My publications:

J.B. Stevens, R.L. Webster, D.G. Barnes, D.J. Pisano, and M.J. Drinkwater.
The HI Content of Compact Groups of Galaxies
Publications of the Astronomical Society of Australia, 21:318-333, 2004 ADS

Publications I have collaborated on:

M.J. Meyer et al.
The HIPASS catalogue - I. Data presentation
Monthly Notices of the Royal Astronomical Society, 350:1195-1209, 2004 ADS

M.A. Zwaan et al.
The HIPASS catalogue - II. Completeness, reliability and parameter accuracy
Monthly Notices of the Royal Astronomical Society, 350:1210-1219, 2004 ADS

M.T. Doyle et al.
The HIPASS catalogue - III. Optical counterparts and isolated dark galaxies
Monthly Notices of the Royal Astronomical Society, 361:34-44, 2005 ADS

O.I. Wong et al.
The Northern HIPASS catalogue - data presentation, completeness and reliability measures
Monthly Notices of the Royal Astronomical Society, 371:1855-1864, 2006 ADS

A. Deller et al.
e-VLBI detection of Circinus X-1 at 1.6 and 8.4 GHz
Astronomer's Telegram, 1037, 2007

Judd D. Bowman et al.
Field Deployment of Prototype Antenna Tiles for the Mileura Widefield Array Low Frequency Demonstrator
Astronomical Journal, 133:1505-1518, 2007 ADS

N.D. Ramesh Bhat et al.
Detection of Crab Giant Pulses Using the Mileura Widefield Array Low Frequency Demonstrator Prototype System
Astrophysical Journal, 665:618-627, 2007 ADS

C.J. Phillips et al.
Detection of compact radio emission from Circinus X-1 with the first Southern hemisphere e-VLBI experiment
Monthly Notices of the Royal Astronomical Society: Letters, 380:L11-14, 2007 ADS