Spitzer Space Telescope - General Observer Proposal #40247


Probing the Gas in the Planet Forming Regions of Protoplanetary Disks

Principal Investigator: Nuria Calvet
           Institution: University of Michigan

     Technical Contact: Catherine Espaillat, University of Michigan

Co-Investigators: 
Catherine Espaillat, University of Michigan                           
James Muzzerolle, University of Arizona                               
Elise Furlan, UCLA                                                    
Lee Hartmann, University of Michigan                                  
Edwin Bergin, University of Michigan                                  
Jon Miller, University of Michigan                                    

Science Category: circumstellar/debris disks 
 Observing Modes: IrsStare 
  Hours Approved: 46.8 

Abstract:
By studying the inner, planet-forming regions of circumstellar disks around
low-mass pre-main sequence stars we can refine theories of giant planet
formation and develop timescales for the evolution of disks and their planets.
Spitzer low-resolution IRS observations of T Tauri stars (TTS) in the
Chamaeleon, IC 348, and NGC 2068/2071 star-forming regions have given us an
unprecedented look at dust evolution in young objects spanning 1-3 Myr.
However, despite this ground breaking progress in studying the dust in young
disks, the gas properties of the inner disk remain essentially unknown. With
high resolution IRS, we propose to search for 12.81 micron Neon fine structure
emission originating in the innermost disk regions of classical TTS in different
stages of evolution with the objective of revealing the timescales of gas
dissipation and its relationship to dust evolution. These observations will
complement ground-based gas studies with Magellan/MIKE and Gemini/Phoenix. With
the combined results of Spitzer, Gemini, and Magellan, our theoretical analysis
will unveil the state of the dust and gas in disks in which planets may already
be forming and starting to open gaps.