Results 31 to 40 of about 1,063,077 (278)
IS POLARIS LEAVING THE CEPHEID INSTABILITY STRIP?
Odessa Astronomical Publications, 2017 Although Polaris is generally regarded as an overtone pulsator that may soon switch to pulsation in the fundamental mode, it is argued that the variable is actually crossing the instability strip for the first time and is in the process of leaving the ...
D. G. Turner
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HST+COS spectra of the double white dwarf CSS 41177 place the secondary inside the pulsational instability strip [PDF]
, 2015 We present Hubble Space Telescope + Cosmic Origins Spectrograph (HST+COS) data of the eclipsing double white dwarf binary CSS 41177. Due to the temperature difference between the two white dwarfs, the HST+COS far-ultraviolet data are dominated by the hot,
M. Bours +3 more
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CONTEMPORARY PROBLEMS OF ASTRONOMY: THE CHEMICAL COMPOSITION OF CEPHEIDS AND RELATED STARS
Odessa Astronomical Publications, 2017 In the short form we present the main results of spectroscopic analysis of the different kind of Cepheids and related stars: double-mode Cepheids, s-Cepheids, non-variable supergiants situated inside the Cepheids instability strip and Cepheids first time
S. M. Andrievsky, V. G. Klochkova
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Resonant Mode Coupling in δ Scuti Stars
The Astrophysical Journal, 2023 Delta Scuti ( δ Sct) variables are intermediate-mass stars that lie at the intersection of the main sequence and the instability strip on the Hertzsprung–Russell diagram.
Mohammed Mourabit, Nevin N. Weinberg
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Wear of Functionally Graded Coatings under Frictional Heating Conditions
Nanomaterials, 2021 Multilayered and functionally graded coatings are extensively used for protection against wear of the working surfaces of mechanisms and machines subjected to sliding contact.
Vladimir B. Zelentsov +2 more
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DISCOVERY OF TWO LITHIUM CEPHEIDS IN THE GALAXY
Odessa Astronomical Publications, 2017 We report about the discovery of two lithium Cepheids in the Galaxy, based on observations made with the echelle spectrograph of the Apache Point Observatory. We have used high- resolution, high signal-to-noise spectra to determine abundances of chemical
V. V. Kovtyukh +2 more
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A theoretical instability strip for rapidly oscillating Ap stars [PDF]
, 2002 M. S. Cunha
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TESS Observations of the Pleiades Cluster: A Nursery for δ Scuti Stars
The Astrophysical Journal Letters, 2023 We studied 89 A- and F-type members of the Pleiades open cluster, including five escaped members. We measured projected rotational velocities ( $v\sin i$ ) for 49 stars and confirmed that stellar rotation causes a broadening of the main sequence in the ...
Timothy R. Bedding +10 more
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The theoretical instability strip of M dwarf stars [PDF]
, 2013 The overstability of the fundamental radial mode in M dwarf models was theoretically predicted by Rodr\'iguez-L\'opez et al. (2012). The periods were found to be in the ranges ~25-40 min and ~4-8 h, depending on stellar age and excitation mechanism.
C. Rodr'iguez-L'opez +7 more
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Pulsation in Intermediate-Mass Stars
Frontiers in Astronomy and Space Sciences, 2018 A new perspective of pulsation in stars within the δ Scuti instability strip has recently emerged as a result of Kepler observations. The majority of stars within the instability strip do not pulsate and practically all δ Scuti stars contain low ...
Luis A. Balona
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