Results 1 to 10 of about 125 (99)
Spectroscopic Determination of Radius Changes of Cepheid Variable Stars [PDF]
Publications of the Astronomical Society of the Pacific, 2007 We introduce a simple method for determining pulsation velocities of Cepheid variables; namely, the matching of observed spectral line profiles in both shape and absolute position with model profiles. This approach avoids the ambiguous meaning of radial velocity for asymmetric lines, and it avoids the awkward projection factor (the "p" factor) used to ...
David F. Gray, Kevin B. Stevenson
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First detection of CO emission from Cepheid Variable stars
, 2023 We present IRAM 30~m Telescope observations of the CO(1-0) and CO(2-1) emission lines in a sample of eight Cepheid variable stars. The CO(1-0) line is detected in four of the eight targets at a signal-to-noise of $>$3.5 confirming the presence of CO in Cepheid atmospheres.
Hamer, S. L., Ardern, S., Scowcroft, V.
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NEW VARIABLE STARS AROUND THE CEPHEID VARIABLE TU CAS
Publications of The Korean Astronomical Society, 2005 Time-series observations were carried out using a 155mm refractor and a CCD camera at Bohyunsan Optical Astronomy Observatory. We found 38 new variable stars in the region around the Cepheid variable TU Cas: 22 eclipsing binary stars, 11 Scuti type stars and an RR Lyrae star, and 4 unclassified variables.
Young-Beom Jeon +3 more
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The MACHO Project LMC Variable Star Inventory: Classical Cepheids, AGB Variables, and the Nine Million Star Color-Magnitude Diagram [PDF]
Symposium - International Astronomical Union, 1999 We measure the ratio of ~ 5M⊙ blue and red LMC supergiants (representative of classical Cepheids) using the MACHO Project's 9 million star color-magnitude diagram (9M CMD) of the LMC bar. We find b/r = 0.39, which favors the Z=0.008, 5M⊙ theoretical model of Schaerer et al. (1993) over that of Fagatto et al. (1994).
Alves, DR, Basu, A, Cook, KH, Welch, DL
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The period-luminosity relation for Cepheid variable stars
The Astrophysical Journal, 1989 Flux-constant, hydrostatic model stellar atmospheres have been calculated using effective temperatures, gravities, and abundances appropriate for Cepheid variable stars. These models have been used to compute synthetic spectra, which have been used to compute synthetic colors and the visual surface brightness parameter S(v). The Johnson system color (V-
R. B. Hindsley, R. A. Bell
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ULTRA-LOW AMPLITUDE VARIABLES IN THE LARGE MAGELLANIC CLOUD—CLASSICAL CEPHEIDS, POP. II CEPHEIDS, RV TAU STARS, AND BINARY VARIABLES [PDF]
The Astrophysical Journal, 2009 A search for variable stars with ultra-low amplitudes (ULAs), in the millimagnitude range, has been made in the combined MACHO and OGLE databases 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 have been uncovered.
Buchler, Robert +2 more
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A three-dimensional map of the Milky Way using classical Cepheid variable stars [PDF]
Science, 2019 Cepheids help to map the Galaxy Cepheid variable stars pulsate, which allows their distances to be determined from the periodic variations in brightness. Skowron et al. constructed a catalog of thousands of Cepheids covering a large fraction of the Milky Way.
Dorota M. Skowron +11 more
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Three classical Cepheid variable stars in the nuclear bulge of the Milky Way [PDF]
Nature, 2011 The nuclear bulge is a region with a radius of about 200 parsecs around the centre of the Milky Way. It contains stars with ages ranging from a few million years to over a billion years, yet its star-formation history and the triggering process for star formation remain to be resolved.
Matsunaga, N. +8 more
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The MACHO Project LMC Variable Star Inventory: Classical Cepheids and AGB Variables
, 1998 This paper has been ...
Alves, D. +20 more
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The Astrophysical Journal, 2002 We present a method for solving the light curve of an eclipsing binary system that contains a Cepheid variable as one of its components as well as the solutions for three eclipsing Cepheids in the Large Magellanic Cloud (LMC). A geometric model is constructed in which the component stars are assumed to be spherical and on circular orbits.
Alcock, Charles +24 more
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