Rene'e C. Kraan-Korteweg (Departamento de Astronomia, Universidad de Guanajuato, Mexico)

Lifting the star and dust veil of the Milky Way - Rene'e C. Kraan-Korteweg Colloquium

ATNF Marsfield Lecture Theatre

Abstract

I will start with a brief overview of deep optical and NIR (2MASS) galaxy
searches and their effectiveness in uncovering the galaxy distribution
behind the Milky Way. While the ability to identify galaxies in the optical
surveys becomes quite ineffective for absorption above 3 mag, this effect
is much less severe in the NIR. However, confusion due to star density is
a strongly delimiting factor. 2MASS does not recover galaxies in regions
where the star density is higher than 10000 per square degree, leaving the
extragalactic sky unmapped in the wide area around the Galactic Bulge (-90 < l
< 90), where optical surveys still do quite well.

We will see that even if galaxies are identified at low Galactic latitudes in
either optical or NIR surveys, spectroscopic follow-ups are hardly successful
in obtaining redshifts when the optical absorption reaches 3 magnitudes or
more, leaving us thus with a a similar ZOA in redshift space. Here only HI
surveys prevail. After a brief review of the results from the deep Parkes
MultiBeam HI ZOA search for galaxies, I will continue with a progress report
on the currently ongoing extension of this survey to higher latitudes around
the Galactic Bulge as well as an update on the spiral galaxy HIZOA J0836-43,
the most massive HI galaxy detected in the HIZOA and deep HIPASS survey,
which, however, lies behind an obscuration screen of 10 mag.