Spitzer Space Telescope - Archive Research Proposal #50029


Extragalactic Cepheids from Spitzer Archival Data

Principal Investigator: Chow Choong Ngeow
           Institution: University of Illinois, Urbana-Champaign

     Technical Contact: Chow Choong Ngeow, University of Illinois, Urbana-Champaign

Co-Investigators: 
Shashi Kanbur, SUNY at Oswego                                         
Lucas Macri, NOAO                                                     

Science Category: local group galaxies 
Dollars Approved: 25000 

Abstract:
We have recently derived the Cepheid Period-Luminosity (PL) relations in the
IRAC bands using archival Spitzer data from the SAGE project. These PL relations
can be used in future distance scale studies with the James Webb Space
Telescope, which will mainly operate in the near and mid infrared. We propose to
test the suitability of the LMC IRAC band PL relations for extragalactic work by
applying them to extragalactic Cepheids present in archival Spitzer observations
of three nearby galaxies: WLM, IC 1613 and M33. We request a funding of $25,000
to carry out this proposal.