The dynamics of Ly-alpha Blobs - Evidence for "super-wind" outflows?
PI:
Richard Bower
Co-I(s):
Toru Yamada, Yuichi Matsuda, Joris Gerssen, Ian Smail, Mark Swinbank, Tomoki Hayashino, Yoshiaki Taniguchi, Kouji Ohta
Abstract
A key problem in cosmology
is the surprisingly low efficiency of galaxy formation. Fewer than 10\% of the baryons
in the universe cool down to form stars. Successful theories
predict that starbursts in early galaxies drive power "super-winds" that drive material out of the
galaxies' haloes. These blast waves would also explain the widespread chemical
enrichment of the universe.
Narrow-band imaging on SUBARU has identified 35 diffuse Ly-alpha emission line
nebulae ("Ly-alpha blobs", LABs) at z=3. This is the first large and systematic
survey able to detect the LAB haloes of normal (L*) galaxies. By examining spatial variation in the emission-line profiles,
we will search for evidence of super wind outflows. The signature of such an outflow is seen in
the halo of one galaxy (C15/LAB8): a statistical sample is now needed so that we can infer the
wind velocity and thus test the theoretical models.