AAS 201st Meeting, January, 2003
Session 112. The ISM: Clouds and Regions
Poster, Thursday, January 9, 2003, 9:20am-4:00pm, Exhibit Hall AB

## [112.27] The HI Environment of MBM40

L. Magnani, M. McCarthy (U. Georgia), R. Sandin-Alvarez (U. Puerto Rico), R. Chastain (U. Georgia)

A 4 deg x 2 deg region centered on MBM40 was mapped in the 21 cm line of atomic hydrogen at the Arecibo Observatory. The angular and velocity resolution of the datacube is 3.4\arcmin and 0.32 km/s, respectively. Channel maps of the region show HI associated with the high-latitude molecular cloud, MBM40, along with filamentary structures in the foreground or background. A comparison with the CO and IRAS 100 \mum data available for this region shows that there is an offset both spatially and in velocity between the molecular and atomic gas. It is likely that this offset reflects the transition from atomic to molecular gas of a larger, pre-existing atomic hydrogen cloud.