Stellar Photometric Variability Within the Central 4 pc of the Galactic Center with Infrared Image Subtraction

نویسندگان

  • Molly S. Peeples
  • K. Z. Stanek
چکیده

We present a catalog of 110 variable stars within ∼ 1 of Sgr A* based on image subtraction of near-infrared (H and K) photometry. Our images were obtained over 133 nights from 2000–2002 in H-band and over 134 nights from 2001–2002 in K-band; the typical FWHM is 1.4. We match the catalog to other near-infrared, X-ray, and radio (i.e., maser) data, and we discuss some of the more interesting objects. The catalog includes 14 periodic sources, several known long-period variables and three new LPV candidates. We associate IRS 10* with OH, SiO, and H2O masers and a bright X-ray point source; this analysis suggests IRS 10* is an AGB star with an accreting companion. Among the ≈ 90 newly discovered sources are a probable cataclysmic variable, a potential edge-on contact 84 day period eclipsing binary, and a possible 41 day period pulsating variable. Subject headings: Galaxy: center — stars: variable

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تاریخ انتشار 2007