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The Zero Point of Extinction Toward Baade's Window

Andrew Gould·Piotr Popowski·Donald M. Terndrup
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Abstract

We measure the zero point of the Stanek (1996) extinction map by comparing the observed (V-K) colors of 206 K giant stars with their intrinsic (V-K)_0 colors as derived from their Hβindices. We find that the zero point of the Stanek map should be changed by ΔA_V = -0.10 +/- 0.06 mag, obtaining as a bonus a three-fold reduction of the previous statistical error. The most direct way to test for systematic errors in this determination would be to conduct a parallel measurement based on the (V-K) colors of RR Lyraes (type ab).

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Andrew Gould, Piotr Popowski, Donald M. Terndrup. 1997-05-05. The Zero Point of Extinction Toward Baade's Window. https://doi.org/10.1086/305062

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