17th of June 2015 |
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ATNF Colloquium |
A wide-field investigation into the HI content of galaxies |
by Helga Denes (CASS) |
Abstract. The environment of a galaxy
can play a major role in its evolution. Late-type gas-rich galaxies can be
transformed into gas-poor early-type galaxies in dense environments.
Observations show that spiral galaxies in galaxy cluster tend to have on
average less neutral hydrogen (HI) than galaxies of the same type and size in
the field. Recently there is accumulating evidence that HI-deficient galaxies
are also relatively frequent in galaxy groups and that galaxy transformation
can already start in the group environment. In this talk I will investigate
how the environment influences the HI content of galaxies, and which
mechanisms are responsible for the gas deficiency in galaxy groups? The color-composite image above shows the extremely HI-poor spiral galaxy ESO 009-G010: blue - GALEX UV, green - DSS optical B-band, and red - ATCA HI distribution. |