Does the Oosterhoff Dichotomy Exist in The Andromeda Galaxy? I. The case of G11
Autor: | Ramos, Rodrigo Contreras, Clementini, Gisella, Federici, Luciana, Fiorentino, Giuliana, Cacciari, Carla, Catelan, Marcio, Smith, Horace A., Pecci, Flavio Fusi, Marconi, Marcella, Pritzl, Barton J., Kinemuchi, Karen |
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Rok vydání: | 2013 |
Předmět: | |
Druh dokumentu: | Working Paper |
DOI: | 10.1088/0004-637X/765/1/71 |
Popis: | We present the first evidence that Oosterhoff type II globular clusters exist in the Andromeda galaxy (M31). On the basis of time-series photometry of the moderately metal-poor ([Fe/H]\sim -1.6 dex) M31 globular cluster G11, obtained with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope, we detected and derived periods for 14 RR Lyrae stars, of which five are found to lie inside the cluster tidal radius. They include three fundamental-mode (RRab) and two first-overtone (RRc) pulsators, with average periods Comment: 23 pages, 14 figures, 4 tables. Fig. 10 (right panel) replaced. ApJ in press |
Databáze: | arXiv |
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