Spitzer Space Telescope - General Observer Proposal #80174


Connecting Young Stellar Object Variability Across the Great Observatories: A
Combined Spitzer and Chandra Study of Variability in IC 348

Principal Investigator: Kevin Flaherty
           Institution: University of Arizona

     Technical Contact: Kevin Flaherty, University of Arizona

Co-Investigators: 
James Muzerolle, STSCI                                                
Zoltan Balog, MPIA                                                    
Elise Furlan, JPL                                                     
Robert Gutermuth, Smith College                                       
William Herbst, Wesleyan University                                   
S. Thomas Megeath, University of Toledo                               
Scott Wolk, Harvard-Smithsonian Center for Astrophysics               

Science Category: young stellar objects 
 Observing Modes: IRAC Post-Cryo Mapping
  Hours Approved: 21.5 

Abstract:
While most of our knowledge of circumstellar disks is based on single snapshots
of many systems, their evolution is in fact highly dynamic on short timescales.
We propose to monitor a cluster of young stars at 3.6 and 4.5 micron with
Spitzer, as well as in the X-ray with Chandra, in order to trace infrared
variability on timescales of months to years as well as connect it with known
sources of X-ray variability. Previous observations have found that many young
stellar objects fluctuate in as little as a few days. Possible sources of this
variability include variable heating by X-ray, accretion or stellar flux,
dynamical interactions with the stellar magnetic field or perturbations from a
possibly planetary-mass companion embedded in the disk. Coordinated Spitzer and
Chandra observations, along with supporting data tracing the accretion and
stellar flux, will be able to put strong constraints on the source of the
variability and study the importance of X-rays in setting the disk structure.
This type of multi-wavelength multi-epoch campaign has not been performed in the
past and has the potential to greatly advance our understanding of young stellar
object evolution.