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Spectrophotometric Libraries, Revised Photonic Passbands, and Zero Points for UBVRI, Hipparcos, and Tycho Photometry
Murphy, Simon; Bessell, Michael
We have calculated improved photonic passbands for the UBVRI, Hipparcos Hp, and Tycho BT and VT standard systems using the extensive spectrophotometric libraries of NGSL and MILES. Using the Hp passband, we adjusted the absolute flux levels of stars in the spectrophotometric libraries so that their synth…
Optimizing Automated Classification of Variable Stars in New Synoptic Surveys
Bloom, Joshua S.; Richards, Joseph W.; Long, James P. +2 more
Efficient and automated classification of periodic variable stars is becoming increasingly important as the scale of astronomical surveys grows. Several recent articles have used methods from machine learning and statistics to construct classifiers on databases of labeled, multi-epoch sources with the intention of using these classifiers to automa…
The [Fe/H] Dependence on the Ca ii- MV Relationship
Pancino, E.; Wallerstein, George; Gomez, T. A.
We have examined the Wilson-Bappu effect, a relationship between the absolute magnitude of the star, MV, and the logarithm of the Ca ii emission width, W0, over the largest MV range to date, +13 to -5, covering M-dwarfs to type Ia supergiants. We used an extensive literature, the latest Hipparcos reduction, data fr…