Schmidt’s Conjecture and Star Formation in Galactic Molecular Clouds and External Galaxies
- Author(s)
- Joao Alves, Charles Lada, Marco Lombardi, Jan Forbrich
- Abstract
The star formation rate and its variation in time are intimately
connected to our understanding of the formation and evolution of the
Milky Way and external galaxies. Ever since the pioneering work of
Martin Schmidt a half-century ago there has been great interest in
finding an appropriate empirical relation that would directly link some
property of interstellar gas with the physical process of star formation
within it. Schmidt conjectured that this might take the form of a
relation between the rate of star formation and the surface density of
the interstellar gas. In this talk I will describe how recent
observations of nearby GMCs made with robust, high-dynamic range
Planck-Herschel-2MASS maps, are providing new insights into the nature
of this relationship. I will show that though a Schmidt relation is
observed within individual molecular clouds, there is no Schmidt law
that characterizes star formation between the clouds in the Milky Way.
Instead, a linear scaling exists between the total SFR and the amount of
dense gas within molecular clouds. This scaling may be the underlying
physical relationship that most directly connects star formation
activity with interstellar gas both between clouds in the Milky Way and
within and between external galaxies. Finally I will discuss the
implications of these results for the Kennicutt-Schmidt relation for
galaxies.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Harvard-Smithsonian Center for Astrophysics, Universitá degli Studi di Milano
- Journal
- IAU General Assembly Meeting
- Volume
- 29
- Pages
- 53581
- Publication date
- 08-2015
- Austrian Fields of Science 2012
- 103003 Astronomy, 103004 Astrophysics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/schmidts-conjecture-and-star-formation-in-galactic-molecular-clouds-and-external-galaxies(ac3020b6-b082-4933-9674-9f9a730e63b4).html