Stellar Clusters in M31 from PHAT: Survey Overview and First Results

L. Clifton Johnson; Anil C. Seth; Julianne J. Dalcanton; Nelson Caldwell; Dimitrios A. Gouliermis; Paul W. Hodge; Soeren S. Larsen; Knut A. G. Olsen; Izaskun San Roman; Ata Sarajedini; Daniel R. Weisz; the PHAT Collaboration

arXiv · 1107.2668

Stellar Clusters in M31 from PHAT: Survey Overview and First Results

L. Clifton Johnson·Anil C. Seth·Julianne J. Dalcanton·Nelson Caldwell·Dimitrios A. Gouliermis·Paul W. Hodge·Soeren S. Larsen·Knut A. G. Olsen·Izaskun San Roman·Ata Sarajedini·Daniel R. Weisz·the PHAT Collaboration

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Abstract

The Panchromatic Hubble Andromeda Treasury (PHAT) is an on-going Hubble Space Telescope (HST) multi-cycle program that will image one-third of the M31 disk at high resolution, with wavelength coverage from the ultraviolet through the near-infrared. This dataset will allow for the construction of the most complete catalog of stellar clusters obtained for a spiral galaxy. Here, we provide an overview of the PHAT survey, a progress report on the status of observations and analysis, and preliminary results from the PHAT cluster program. Although only ~20% of the survey is complete, the superior resolution of HST has allowed us to identify hundreds of new intermediate and low mass clusters. As a result, the size of the cluster sample within the Year 1 survey footprint has grown by a factor of three relative to previous catalogs.

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L. Clifton Johnson, Anil C. Seth, Julianne J. Dalcanton, Nelson Caldwell, Dimitrios A. Gouliermis, Paul W. Hodge, Soeren S. Larsen, Knut A. G. Olsen, Izaskun San Roman, Ata Sarajedini, Daniel R. Weisz, the PHAT Collaboration. 2011-07-13. Stellar Clusters in M31 from PHAT: Survey Overview and First Results. https://arxiv.org/abs/1107.2668

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