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arXiv · astro-ph/9706292

The Zero Point of Extinction Toward Baade's Window From RR Lyrae Stars

C. Alcock·R. A. Allsman·D. R. Alves·T. S. Axelrod·A. C. Becker·D. P. Bennett·K. H. Cook·K. C. Freeman·K. Griest·A. Gould·J. A. Guern·M. J. Lehner·S. L. Marshall·D. Minniti·B. A. Peterson·P. Popowski·M. R. Pratt·P. J. Quinn·A. W. Rodgers·C. W. Stubbs·W. Sutherland·T. Vandehei·D. L. Welch
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Abstract

We measure the zero point of the Stanek (1996) extinction map by comparing the observed (V-K) colors of 20 RR Lyrae stars (type ab) found in the MACHO survey with their intrinsic (V-K)_0 colors as a function of period as determined from nearby RR Lyrae stars. We find that the zero point of the Stanek map should be changed by ΔA_V = -0.11 +/- 0.05 mag, in excellent agreement with the recent measurement of Gould, Popowski & Terndrup (1997) using K giants.

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C. Alcock, R. A. Allsman, D. R. Alves, T. S. Axelrod, A. C. Becker, D. P. Bennett, K. H. Cook, K. C. Freeman, K. Griest, A. Gould, J. A. Guern, M. J. Lehner, S. L. Marshall, D. Minniti, B. A. Peterson, P. Popowski, M. R. Pratt, P. J. Quinn, A. W. Rodgers, C. W. Stubbs, W. Sutherland, T. Vandehei, D. L. Welch. 1997-06-30. The Zero Point of Extinction Toward Baade's Window From RR Lyrae Stars. https://doi.org/10.1086/305206

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