A “Short” Distance to the Large Magellanic Cloud With the Hipparcos Calibrated Red Clump Stars
نویسنده
چکیده
Following an approach developed by Paczyński & Stanek, we derive a distance to the Large Magellanic Cloud (LMC) by comparing red clump stars from the Hipparcos catalog with the red clump stars observed in two fields in the LMC that were selected from the ongoing photometric survey of the Magellanic Clouds to lie in low extinction regions. The use of red clump stars allows a single step determination of the distance modulus to the LMC, μ0,LMC = 18.065± 0.031± 0.09 mag (statistical plus systematic error), and the corresponding distance, RLMC = 41.02 ± 0.59 ± 1.74 kpc. This measurement is in excellent agreement with the recent determination by Udalski et al., also based on the red clump stars, but is ∼ 0.4 mag smaller than the generally accepted value of μ0,LMC = 18.50± 0.15 mag. We discuss possible reasons for this discrepancy and how it can be resolved. Subject headings: galaxies: distances and redshifts — galaxies: individual (LMC) — Solar neighborhood — stars: horizontal-branch On leave from Copernicus Astronomical Center, Warsaw, Poland
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