WUNA Lunch Talk:

M. Nurur Rahman

Department of Astronomy, University of Maryland

Constraining the Functional Form between the Molecular Gas and Star Formation

November 17

12:10PM, Note unusual location: CV-Auditorium (rm 225)


What is the power law index in the spatially resolved molecular gas Kennicutt-Schmidt relation ? Whether the relation between molecular gas and star formation is linear or not has important implications on the physics regulating star formation activity on galactic scales. Observational studies, however, frequently arrive at inconsistent results even on the same object, mostly because of methodological differences. We discuss a systematic study carried out on a nearby galactic disk (M99), which assesses the effects of the choice of SFR tracer, the removal of diffuse emission, and the sampling and fitting methodologies. We find that while the result for the power law index in the faint emission is very sensitive to the methodology, the result of the measurement is well defined in the bright regions of galaxies. There we obtain an approximately linear relation independent of the choice of SFR tracer if the fraction of diffuse emission is smaller than 30-40%.