Results 21 to 30 of about 411 (243)

Annual parallax measurements of a Mira variable star, U Lyncis [PDF]

Publications of the Astronomical Society of Japan, 2015
Abstract We have measured the annual parallax of the water maser around a Mira star, U Lyncis (U Lyn) with VLBI Exploration of Radio Astrometry (VERA). The value of the parallax is 1.27 ± 0.06 mas, corresponding to a distance of $786^{+40}_{-36}\:$pc. This is the first VLBI measurement of the parallax of U Lyn. We obtained the period and
Tatsuya Kamezaki, Akiharu Nakagawa, Toshihiro Omodaka, Toshihiro Handa, Kan-ichiro Inoue, Tomoharu Kurayama, Hideyuki Kobayashi, Takumi Nagayama, Yuji Ueno   +8 more
openaire   +1 more source

Influence of a Close Companion on the Variability of a Mira-Type Star [PDF]

International Astronomical Union Colloquium, 2000
AbstractThe effects of a low-mass companion (a planet?) revolving around a red giant at a short distance (inside its circumstellar envelope) are discussed. Calculations are given for a conical shock wave, induced by the orbital motion of the companion. Consequences for the stellar spectrum and light curve are derived, and predictions for the evolution ...
openaire   +1 more source

DISCOVERY OF MIRA VARIABLE STARS IN THE METAL-POOR SEXTANS DWARF SPHEROIDAL GALAXY [PDF]

The Astrophysical Journal, 2012
We report the discovery of two Mira variable stars (Miras) toward the Sextans dwarf spheroidal (dSph) galaxy. We performed optical long-term monitoring observations for two red stars in the Sextans dSph. The light curves of both stars in the $I_{\rm c}$ band show large-amplitude (3.7 and 0.9 mag) and long-period ($326\pm 15$ and $122\pm 5$ days ...
Sakamoto, T., Matsunaga, N., Hasegawa, T., Nakada, Y.   +3 more
openaire   +2 more sources

Time-Dependent Diameters Of Mira Variable Stars

, 2016
We examined archival data of the Palomar Testbed Inteferometer (PTI) covering a sample of 85 Mira variable stars. The sample contains the three most common types: 65 oxygen-rich (M-type), 11 carbon-rich (C-type) and 9 of the intermediary S-type; Periods range from 150 to 600 days.
Ruiz Velasco, Alma, van Belle, Gerard, Creech-Eakman, Michelle   +2 more
openaire   +2 more sources

Period Doubling in Variable Stars: A Tentative Interpretation of Oberved Light Curves of Variable White Dwarfs and Mira Stars [PDF]

International Astronomical Union Colloquium, 1989
AbstractIrregular pulsations are commonly observed in many groups of pulsating stars. An interpretation in terms of superposition of modes of pulsation is sometimes barely convincing when too many modes have to be considered and when unexpected ratios of frequenceis are observed.
M.J. Goupil, A. Baglin, M. Auvergne
openaire   +1 more source

The visible spectra of Southern Hemisphere Mira variable stars

The Astrophysical Journal Supplement Series, 1988
Extansion du catalogue de 1974 de Keenan, Garrison et Deutsch, par l'addition de 483 spectrogrammes de 72 etoiles Mira de l'hemisphere ...
Richard A. Crowe, Robert F. Garrison
openaire   +1 more source

WAVELET ANALYSIS OF 173 SEMI-REGULAR VARIABLES

Odessa Astronomical Publications, 2010
We made the wavelet analysis of 173 semi-regular pulsating variable stars of different sub-types. For the analysis, we have used 1,000,000 individual brightness estimates from the published international databases of the VSOLJ (Japan) and AFOEV (France).
L. L. Chinarova
doaj   +1 more source

Angular Size Measurements of Mira Variable Stars at 2.2 Microns. II.

The Astronomical Journal, 2002
We present angular size measurements of 22 oxygen-rich Mira variable stars. These data are part of a long term observational program using the Infrared Optical Telescope Array (IOTA) to characterize the observable behavior of these stars. Complementing the infrared angular size measurements, values for variable star phase, spectral type, bolometric ...
van Belle, G. T., Thompson, R. R., Creech-Eakman, M. J.   +2 more
openaire   +2 more sources

Envelope tomography of long-period variable stars [PDF]

Astronomy & Astrophysics, 2001
Accepted by Astronomy & Astrophysics (21 pages, 15 figures)
Alvarez, Rodrigo, Jorissen, Alain, Plez, Bertrand, Gillet, Denis, Fokin, Andrej, Dedecker, Maya   +5 more
openaire   +3 more sources

Temporal Changes in the Infrared Spectra of Magellanic Carbon Stars

Galaxies
The Medium-Resolution Spectrometer on the Mid-Infrared Instrument on the JWST obtained spectra of three carbon stars in the Large Magellanic Cloud. Two of the spectra differ significantly from spectra obtained ∼16–19 years earlier with the Infrared ...
G. C. Sloan, K. E. Kraemer, B. Aringer, J. Cami, K. Eriksson, S. Höfner, E. Lagadec, M. Matsuura, I. McDonald, E. Montiel, R. Sahai, A. A. Zijlstra   +11 more
doaj   +1 more source