Spitzer Space Telescope - Archive Research Proposal #50145


Archival Survey of Orion A with Spitzer, XMM-Newton and Chandra

Principal Investigator: Scott Wolk
           Institution: Harvard Smithsonian Center for Astrophysics

     Technical Contact: Scott Wolk, Harvard Smithsonian Center for Astrophysics

Co-Investigators: 
Elaine Winston, SAO (currently Dublin)                                
S. Thomas Megeath, University of Toledo                               
Lori Allen, SAO                                                       
Robert Gutermuth, SAO                                                 
Salvatore Salvatore, INAF                                             
Phil Myers, SAO                                                       
Lee Hartmann, University of Michigan                                  
Giusi Micela, INAF                                                    
John Stauffer, IPAC                                                   
Luisa Rebull, IPAC                                                    
Marc Gagne, West Chester University                                   
John Bally, University of Colorado                                    
Joanna Oliveira, Keele                                                
Fred Walter, SUNY Stony Brook                                         

Science Category: star formation 
Dollars Approved: 75000 

Abstract:
We propose an archival project to combine data from the Spitzer GTO surveys of
the Orion A cloud with archival XMM-Newton and Chandra observations of the same
region and our own ground based spectra to better understand star formation in
the nearest giant molecular cloud. To understand the evolution of stars and
disks in the first million years requires a large sample. The Spitzer Orion GTO
surveys contain 1800+ Class 0, I, and II stars and an unknown number of Class
III sources. The X-ray observations, which include over 2000 sources, are the
premier method of identifying the remaining young stars WITHOUT disks.
Combining these data with ground based optical spectra and sub-mm observations
we will: - Identify the PMS stars without disks. - Determine the demographics of
stars (clusters, groups, isolation) as a function of evolutionary class. - Study
the relative importance of clustered versus isolated star formation. - Examine
the effect of environment on star formation and disk evolution. - Examine the
relative duration of the Class II and transition disk phases and the commonality
of inner disk holes. - Study the evolution of the X-ray emitting plasma from the
protostellar to the pre-main sequence phases. - Study the possible effect of
X-rays on evolving disk systems. GMCs are the dominant sites of star formation
in our Galaxy. The combination of data from optical, infrared and sub-mm surveys
will provide the most complete survey of star formation in a GMC to date. With
these data, we hope to better understand the star forming process in GMCs, and
what distinguishes these massive clouds from nearby dark cloud complexes such as
Taurus and Ophiuchus.