Spitzer Space Telescope - Guaranteed Time Observer Proposal #40228


Searching for Companions to a New Member of the 5 pc Sample

Principal Investigator: Giovanni Fazio
           Institution: Smithsonian Astrophysical Observatory

     Technical Contact: Massimo Marengo, Smithsonian Astrophysical Observatory

Co-Investigators: 
Massimo Marengo, Smithsonian Astrophysical Observatory                
Kevin Luhman, Pennsylvania State University                           
Brian Patten, Smithsonian Astrophysical Observatory/NSF               
Joseph Hora, Smithsonian Astrophysical Observatory                    
John Stauffer, Spitzer Sciance Center                                 
Michael Schuster, University of Minnesota/SAO                         
Peter Allen, Pennsylvania State University                            
Joseph Carson, Jet Propulsion Laboratory                              
Richard Ellis, Brown University                                       

Science Category: brown dwarfs/very low mass stars 
 Observing Modes: IracMap 
  Hours Approved: 0.2 

Abstract:
The IRAC GTO team has used IRAC to search for brown dwarf companions to all
known stars and brown dwarfs within 5 pc from the Sun. A new member of the solar
neighborhood, SCR 1845-6357 (M8.5V), has been recently discovered at a distance
of 3.85 pc, making it the 24th closest object to the Sun (Hambly et al. 2004;
Henry et al. 2006). High-resolution imaging has revealed a T dwarf companion at
a separation of 1" from this star (Biller et al. 2006). We propose to obtain
IRAC images of SCR 1845-6357 to search for additional brown dwarf companions at
wider separations.