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Star formation surveys with Herschel SPIRE-PACS

Guaranteed time key programmes for the Herschel Space Observatory

+ SPIRE consortium
+ PACS consortium

  Gould belt survey
  - Proposal (pdf)
  - Constitution (pdf)
  - Publication (pdf)

PI: Philippe André
Paolo Saraceno

A. Abergel, P. Ade, J.-P. Baluteau, M. Benedettini, J.-Ph. Bernard, J. Blommaert, S. Bontemps,
L. Cambrésy, P. Cox, P. Didelon, J. Di Francesco, A. Di Giorgio, M. Griffin, P. Hargrave, Th. Henning, M. Huang, J. Kirk, O. Krause, R. Launhardt, S. Leeks, J. Li, P. Martin, A. Men’shchikov, B. Merín, V. Minier, S. Molinari, F. Motte, G. Olofsson, A. Omont, S. Pezzuto, T. Prusti, P. Royer, D. Russeil, M. Sauvage , N. Schneider, B. Sibthorpe , A. Sicilia-Aguilar, L. Spinoglio, L. Testi, R. Vavrek, C. Waelkens, D. Ward-Thompson, G. White, C. Wilson, A. Woodcraft, A. Zavagno

461 hours

Probing the origin of the stellar initial mass function:
A wide-field Herschel photometric survey of nearby star-forming cloud complexes

Herschel provides a unique opportunity to study the earliest stages of star formation. What is the origin of the stellar initial mass function (IMF)? This issue is central in local star formation research and for understanding whether the IMF is truly universal or is likely to depend on metallicity, pressure, or temperature. As prestellar cores and young (Class 0) protostars emit the bulk of their luminosity at ~80-400 microns, the Herschel imaging instruments SPIRE and PACS are ideal for takinga census of such objects down to ~0.01-0.1 Msun in the nearby (0.5 kpc) molecular cloud complexes. We propose an extensive imaging survey of the densest portions of the Gould Belt with SPIRE at 250-500 and PACS at 110-170 microns down to a 5-sigma column sensitivity NH2~1021 cm^-2 or Av~1. Our goal is to make a complete, homogeneous mapping of the Av>3 regions with SPIRE and of the Av>6 regions with PACS, and representative areas at Av~1-3 levels with both instruments. The survey sensitivity is well matched to the expected cirrus confusion limit, so we should detect structures throughout the maps. The target clouds span a range of physical conditions, from active, cluster-forming complexes to quiescent regions with lower star formation activity. We should detect hundreds Class 0 protostars and thousands prestellar condensations in the entire ~145 deg^2 SPIRE survey, i.e. ~10 times more cold objects than already identified from the ground. These numbers should allow us to derive an accurate prestellar core mass function. The temperature and density structures of the nearest ( 0.2 kpc) cores will be resolved, revealing the initial conditions for individual protostellar collapse. The large spatial dynamic range of the proposed survey will probe the link between diffuse cirrus-like structures and compact self-gravitating cores. Our main scientific goal is to elucidate the physical mechanisms for the formation of prestellar cores out of the diffuse medium, crucial for understanding the origin of stellar masses.


Cloud complex AOR
summary AOR
  field image Cardiff/Saclay field image Saclay
summary AOR
field image Saclay/Cardiff field image Saclay
Pipe nebula
summary AOR
field image Saclay field image Saclay
Polaris flare
summary AOR
field image Orsay/Saclay field image SAG3/SAG4
summary AOR
field image Rome/RAL field image Rome/Leuven
summary AOR
field image Saclay field image Saclay
Cham I-III & Musca 
summary AOR
field image HSC/Saclay field image Leuven/HSC
Corona Australis
summary AOR
field image RAL/Cardiff field image Heidelberg
Serpens/Aquila rift
summary AOR
field image Rome/RAL/
field image Rome/Arcetri
summary AOR
field image Rome/Canada field image Rome
IC 5146
summary AOR
field image Marseille field image Saclay
Cepheus flare
summary AOR
field image Canada field image SAG3/Canada
Orion A/Orion B 
summary AOR
field image Rome/Canada
field image Rome
* SPIRE/PACS parallel mode
** PACS only

Editor: Vincent Minier                                    
Last update: 02/01/2008