Spitzer Space Telescope - General Observer Proposal #80053


Hunting Coreshines with Spitzer 

Principal Investigator: Roberta Paladini
           Institution: Spitzer Science Center

     Technical Contact: Roberta Paladini, Spitzer Science Center

Co-Investigators: 
Laurent Pagani, LERMA, Observatoire de Paris                          
Juergen Steinacker, Max Planck Institute fur Astronomie               
Sean Carey, Spitzer Science Center/Caltech                            
Mika Juvela, University of Helsinki                                   
Isabelle Ristorcelli, IRAP, Toulouse                                  
Veli-Matti Pelkonen, IPAC/Caltech                                     
Ludovic Montier, IRAP, Toulouse                                       
Alberto Noriega-Crespo, Spitzer Science Center/Caltech                
Aurore Bacmann, IPAG, Grenoble                                        
Peregrine McGehee, IPAC/Caltech                                       
Douglas Marshall, IRAP, Toulouse                                      

Science Category: star formation 
 Observing Modes: IRAC Post-Cryo Mapping
  Hours Approved: 165.9 

Abstract:
We propose deep Spitzer observations of a large sample of cold clumps selected
from the newly released Planck Early Cold Cores Catalog. The proposed survey,
characterized by uniform depth, will provide the first unbiased investigation of
the coreshine effect in Galactic cold condensations.The coreshine effect,
recently identified by Pagani et al. (2010) and Steinacker et al. (2010), is
interpreted as direct evidence for dust growth in the dense, cold environments
in the interior of molecular clouds. Understanding of the coagulation process is
crucial for the investigation of further coagulation taking place in
protostellar disks, and fundamental for improving our knowledge of the
mechanisms regulating the formation of planets. In addition, grain coagulation
in dense molecular environments could in principle change the global scenario of
dust particles in the diffuse ISM, as a retransfer of grains from these cold
condensations back into the diffuse medium is indeed likely (Ossenkopf 1993).
Last but not least, the existence of a larger population of grains will have
strong implications on our interpretation of both thermal continuum and emission
line data, therefore impacting in a significant way our present view of how
stars form. A by-product of the proposed observations will be an unbiased
serendipitous survey of low-mass outflows, as well as candidate young stellar
objects.