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A New Procedure for the Photometric Parallax Estimation

S. Karaali·Y. Karatas·S. Bilir·S. Ak·E. Hamzaoglu
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Abstract

We present a new procedure for photometric parallax estimation. The data for 1236 stars provide calibrations between the absolute magnitude offset from the Hyades main-sequence and the UV-excess for different (B-V)o colour-index intervals, i.e.: (0.3 0.4), (0.4 0.5), (0.5 0.6), (0.6 0.7), (0.7 0.8), (0.8 0.9), (0.9 1.0), and (1.0 1.1). The mean difference between the original and estimated absolute magnitudes and the corresponding standard deviation are rather small, +0.0002 and +/-0.0613 mag. The procedure has been adapted to the Sloan photometry by means of colour equations and applied to a set of artificial stars with different metallicity. The comparison of the absolute magnitudes estimated by the new procedure and the canonical one indicates that a single colour-magnitude diagram does not supply reliable absolute magnitudes for stars with large range of metallicity.

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S. Karaali, Y. Karatas, S. Bilir, S. Ak, E. Hamzaoglu. 2003-06-19. A New Procedure for the Photometric Parallax Estimation. https://doi.org/10.1071/as03022

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