My current research interests mainly encompasses the study of star formation in the Local Universe using multiwavelength observations.
- Cluster environment effects on galaxy evolution
I am currently working with the VIVA collaboration on the effects of the cluster environment on the star formation and evolution of individual galaxies within the Virgo Cluster as shown via optical (R-band & H&alpha), IR (Spitzer) and UV (GALEX) observations. Apart from gravitational interactions with neighbouring galaxies, the main effect of the cluster environment on individual cluster galaxies is the interaction between the hot ICM and the ISM of a galaxy. This interaction usually results in ram pressure stripping whereby the dust and gas get stripped out of the galaxy as the galaxy falls towards the cluster centre.
- Tidal interactions of galaxies and ring galaxies
I am also interested in the formation of ring galaxies and the effects of tidal interactions. Recently, my collaborators and I discovered a nearby drop-through ring galaxy, NGC 922 which resulted from a high velocity collision of a compact dwarf galaxy with a disk galaxy. This galaxy appears very similar in morphology to the class of high-z galaxies known as `clump cluster' galaxies discovered via the Hubble Ultra Deep Field (HUDF) survey. Hence, detailed studies of local ring galaxies are useful for studying high-z galaxy formation since these `clump cluster' galaxies appear to be fairly common in the early Universe.
- Star formation studies based solely on the gas content
One of my other projects is a multiwavelength star formation survey (SINGG-SUNGG) in the H&alpha and UV (GALEX) of nearby gas rich galaxies selected from HIPASS. These surveys sample the galaxies that could form stars and provide a view of local star formation demographics which is not biased by optical and infrared selection effects.
- HI surveys
HI surveys are useful as neutral gas is present in almost all star-forming galaxies and is affected quite easily by the environment. Hence HI provides a useful indicator of the recent star formation history and galaxy evolution. The HI Parkes All Sky Survey (HIPASS) is an all-sky survey of neutral Hydrogen covering 71% of the entire sky using the Parkes radio telescope in Australia. My work covered the northern extension (Northern HIPASS) which extended the survey from +2 degrees in declination to +25.5, which covers the entire region in and around the Virgo Cluster.