GBT17B-015

GBT high-sensitivity mapping of an HI cloud in the Fermi Bubble wind

Abstract

There is a neutral cloud embedded in the Fermi Bubble wind that we have detected both in 21cm emission with the GBT and in UV absorption lines of CII, CIV, SiII, SiIII, SiIV, and OI with the HST. 21cm observations with the GBT show that the cloud is extended, but existing data lack the sensitivity and coverage to allow us to determine its full extent and mass. We would like to make more extensive, more sensitive 21cm observations of this cloud with the GBT to determine the lifetime of the cloud against disruption by ablation and by photo-evaportaion, and to constrain the outflow rate of the nuclear wind. This cloud is the only cloud in the Fermi bubble wind that is detected in both 21cm emission and UV absorption lines.

Investigators

Name	Institution
Jay Lockman	Green Bank Observatory
Andrew Fox	Space Telescope Science Institute
Rongmon Bordoloi *	North Carolina State University

* indicates the PI