Hst Photometry of the Globular Cluster M4

نویسندگان

  • JAMES E. HESSER
  • CARLTON PRYOR
  • PETER B. STETSON
چکیده

This paper presents a detailed description of the acquisition and processing of a large body of imaging data for three fields in the globular cluster M4 taken with the Wide Field and Planetary Camera 2 aboard the Hubble Space Telescope. Analysis with the ALLFRAME package yielded the deepest photometry yet obtained for this cluster. The resulting data-set for 4708 stars (positions and calibrated photometry in V, I, and, in two fields, U) spanning approximately six cluster core radii is available on the AAS CD-ROM (or email a request to RAI). The scientific analysis is deferred to three companion papers, which investigate the significant white dwarf population discovered and the main sequence population. Subject headings: globular clusters, photometry, white dwarfs, red dwarfs

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تاریخ انتشار 1998