[Previous] | [Session 90] | [Next]

[90.01] Exposing the Dwarf Irregular UGC 7636 : Stripping at Work in the Virgo Cluster

H. Lee (York University), M. G. Richer (Instituto de Astronom\'{i}a, UNAM), M. L. McCall (York University)

We present the results of optical spectroscopy of a newly discovered H~II region residing in the H~I gas cloud located between the dwarf irregular galaxy UGC~7636 and the giant elliptical galaxy NGC~4472 in the Virgo Cluster. A comparison of the properties of UGC~7636 with nearby dwarf irregulars shows that (1) the oxygen abundance of the cloud agrees with that expected for a galaxy with the blue luminosity of UGC~7636, and (2) M_{H I}/L_B for UGC~7636 becomes consistent with the measured oxygen abundance of the cloud if the H~I mass of the cloud is added back into UGC~7636. We conclude that our measurement of the chemical properties of the H~I cloud is strong evidence that the ``isolated'' gas is in fact the stripped interstellar medium of UGC~7636.