PhD Research
The Local Sphere of Influence Survey
The Local Sphere of Influence (LSI) survey is a deep near-IR (H-band) survey of galaxies residing in the Local Sphere of Influence (D < 10 Mpc). The images with a typical surface brightness limit 4 mag fainter than 2MASS (24.5 mag arcsec-2 < SBlim < 26 mag arcsec-2 ) have been obtained with IRIS2 on the 3.9~m Anglo-Australian Telescope. 11 of the observations have resulted in non-dections or the images were saturated by foreground stars. A total of 22 galaxies that remained previously undetected in the NIR and potentially could have been genuinely young galaxies were found to have central surface brightnesses 1 - 2 magnitudes below the 2MASS detection threshold. The cleaned near-infrared images reveal the morphology and extent of many of the galaxies for the first time. For all program galaxies, we derive radial luminosity profiles, ellipticities, and position angles, together with global parameters such as total magnitude, mean effective surface brightness and half-light radius.
Our aims are to:
- carry out an empirical investigation of galaxy structure at near-IR wavelengths
- explore of known optical correlations at dust free wavelengths
- quantify the connection between the near-IR light and the mass distributions (dynamical and stellar)
- measure the near-IR luminosity (mass) and size function of galaxies
- carry out a multiwavelength study of the stellar (near-IR), dust (optical - near-IR), gas (HI) and dark matter distribution (HI)
A first paper has been accepted for publication by the Astronomical Journal containing details of the survey and the near-IR galaxy parameters.
The Local Volume HI Survey
The Local Volume HI Survey (LVHIS) is a project comprising deep HI line and 20-cm radio continuum observations for all nearby, gas-rich galaxies. Our initial sample consists of all galaxies with vLG < 550 km/s or D < 10 Mpc that are detected in the `HI Parkes All-Sky Survey' (HIPASS). A declination limit of DEC < -30 degrees was chosen for observations with the Australia Telescope Compact Array (ATCA).
Our aim is to study the HI distribution and kinematics of Local Volume galaxies as well as their star formation properties on all scales. This will be achieved by obtaining full 12-h synthesis observations with three ATCA configurations (EW352/367-m, 750-m, and 1.5-km). For galaxies with extended HI envelopes we will also obtain HI mosaics in the H75 array, the most compact ATCA configuration.
The Maximum Baryonic Content of Galaxies
Under construction... (To contain details of work on the HI mass-to-light ratio, the maximum baryonic content of galaxies, the mass of the Milky Way).