EPoS Contribution
EPoS Contribution
The 140000 sources of the Hi-GAL Physical Catalog

Davide Elia
The advent of Herschel produced a relevant improvement of our knowledge about star formation, especially regarding its early phases, thanks to large survey projects in a wavelength range (70-500 micron) which is crucial to probe the physical conditions of extremely cold (10-20K) gas and dust condensations. In this respect, Hi-GAL, the unbiased survey of the entire Galactic plane, made available a vast mine of regions for studying star formation, especially in the high-mass regime, in different Galactic environments, providing an overall view of the Milky Way as a star formation engine. Here we present the first release of the Hi-GAL Physical Catalog, constituted by about 140000 entries, namely the compact sources detected by Herschel and showing a regular spectral energy distribution, eligible for grey-body fit. Complementary MSX, WISE, MIPSGAL, ATLASGAL and BGPS photometry is also used to extend the wavelength coverage. We show the statistical distribution of temperature, mass, surface density, bolometric luminosity, etc. for all sources, using them to build an evolutionary picture, and to search for conditions for high mass star formation to occur. The analysis of the aforementioned observables reveals a quite clear separation between the two classes of protostellar and prestellar clumps. Also, the statistics of these quantities is discussed with respect to the source displacement across the Galactic plane: differences between inner and outer Galaxy, whose global star formation properties are poorly explored so far and Hi-GAL statistics are presented here for the first time, are highlighted, and the role of spiral arms is investigated. Finally, both a global estimate of the star formation rate for the Milky Way is provided and the contributions given by single regions of the plane are discussed.
S. Molinari, INAF-IAPS, IT
E. Schisano, INAF-IAPS, IT
M. Merello, INAF-IAPS, IT
M. Pestalozzi, INAF-IAPS, IT
S. Pezzuto, INAF-IAPS, IT
M. Benedettini, INAF-IAPS, IT
A. Di Giorgio, INAF-IAPS, IT
and Hi-GAL collaboration
Suggested Session: Massive Star Formation