Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2012
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012aas...21920102w&link_type=abstract
American Astronomical Society, AAS Meeting #219, #201.02
Astronomy and Astrophysics
Astronomy
Scientific paper
Understanding star formation in low-metallicity systems is challenging due to the lack of detectable molecular gas (using CO as a tracer) in these environments. As star formation occurs primarily within molecular clouds, understanding how and where these clouds are most likely to form is an important piece of the star formation puzzle. Since the atomic hydrogen (HI) gas in star forming galaxies is the reservoir from which the molecular gas forms, cold HI is believed to be a necessary phase in converting the ubiquitous warm HI gas into cold molecular gas. Tracing the locations of cold HI gas via narrow HI line emission (e.g., Young et al. 1996, 1997) in low metallicity galaxies may currently be the best way to identify future sites of star formation. The uniformly high spectral (0.65 - 1.3 km/s) and spatial ( 300 pc) resolution of the VLA-ANGST survey is ideally suited for identifying cold HI through line-of-sight narrow line emission. The VLA-ANGST sample consists of 36 nearby (ɜ Mpc) low mass galaxies beyond the Local Group. We have detected cold HI in every galaxy observed with sufficient signal to noise ( 20). The cold HI is typically near to, but not coincident with the peaks of the total HI emission. The cold HI also constitutes 20-30% of the line flux, so it is never the dominant phase in the local interstellar medium.
Dalcanton Julianne J.
de Blok W. J. G. E.
Koribalski Baerbel
Ott Jorgen
Petersen Eric A.
No associations
LandOfFree
Cold HI in Low Mass Galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cold HI in Low Mass Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cold HI in Low Mass Galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1577349