Ayesha Begum Tareen (RESEARCH SCHOLAR, NATIONAL CENTRE FOR RADIO ASTROPHYSICS, TIFR)

Kinematics of Faint Dwarf Irregular Galaxies - Ayesha Begum Tareen Lunch Talk

ATNF Marsfield Lecture Theatre

Abstract

In this talk I will present the results of recent high velocity
resolution (1.6 km/s), GMRT HI 21cm observations of extremely faint
(M_B > 12.0) dwarf irregular galaxies. Prior to our observations,
it was widely believed that the gas in these galaxies showed only
random motions. However, our high velocity resolution observations
show that these galaxies have systematic large scale velocity
patterns. Some of these patterns can be well described as arising
from rotating disks. For these galaxies, we construct mass models
and find that (i) they are much more dark matter dominated than
normal spiral galaxies, and (ii) their dark matter halos have
constant density cores, as opposed to the cusped density cores
expected from numerical models of galaxy formation.