ULTRA-LOW AMPLITUDE VARIABLES IN THE LARGE MAGELLANIC CLOUD—CLASSICAL CEPHEIDS, POP. II CEPHEIDS, RV TAU STARS, AND BINARY VARIABLES
نویسندگان
چکیده
منابع مشابه
Ultra-low Amplitude Variables in the Lmc – Classical Cepheids, Pop. Ii Cepheids, Rv Tau Stars and Binary Variables
A search for variable stars with ultra-low amplitudes (ULA), in the millimag range, has been made in the combined MACHO and OGLE data bases in the broad vicinity of the Cepheid instability strip in the HR diagram. A total of 25 singly periodic and 4 multiply periodic ULA objects has been uncovered. Our analysis does not allow us to distinguish between pulsational and ellipsoidal (binary) variab...
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The MACHO variables of LMC Field 77 that lie in the vicinity of the Cepheid instability strip are reexamined. Among the 144 variables that we identify as Cepheids we find 14 that have Fourier amplitudes < 0.05 mag in the MACHO red band, of which 7 have an amplitude < 0.006mag : we dub the latter group of stars ultra-low amplitude (ULA) Cepheids. The variability of these objects is verified by a...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2009
ISSN: 0004-637X,1538-4357
DOI: 10.1088/0004-637x/698/1/944