Results 1 to 10 of about 73 (71)

The Secret Lives of Cepheids: δ Cep—The Prototype of a New Class of Pulsating X-Ray Variable Stars^* [PDF]

The Astrophysical Journal, 2017
Abstract From our Secret Lives of Cepheids program, the prototype Classical Cepheid, δ Cep, is found to be an X-ray source with periodic pulsation-modulated X-ray variations. This finding complements our earlier reported phase-dependent FUV–UV emissions of the star that increase ∼10–20 times with highest fluxes at
Scott G. Engle, Edward F. Guinan, Graham M. Harper, Manfred Cuntz, Nancy Remage Evans, Hilding R. Neilson, Diaa E. Fawzy   +6 more
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Synthetic Population of Binary Cepheids. II. The Effect of Companion Light on the Extragalactic Distance Scale

The Astrophysical Journal, 2023
Because of their period–luminosity relation (PLR), classical Cepheids play a key role in the calibration of the extragalactic distance scale and the determination of the Hubble–Lemaître constant H _0 .
Paulina Karczmarek, Gergely Hajdu, Grzegorz Pietrzyński, Wolfgang Gieren, Weronika Narloch, Radosław Smolec, Grzegorz Wiktorowicz, Krzysztof Belczynski   +7 more
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Variable stars in the Gaia era: Mira, RR Lyrae, δ and Type-II Cepheids [PDF]

Proceedings of the International Astronomical Union, 2017
AbstractClassical variables like RR Lyrae, classical and Type-II Cepheids and Mira variables all follow period-luminosity relations that make them interesting as distance indicators. Especially the RR Lyrae and δ Cepheids are crucial in establishing the distance scale in the Universe, and all classes of variables can be used as tracers of galactic ...
openaire   +2 more sources

Discovery of the Longest-period Classical Cepheid in the Milky Way

The Astrophysical Journal Letters
We report the discovery of the classical Cepheid OGLE-GD-CEP-1884 (= GDS_J1535467-555656) with the longest pulsation period known in our Galaxy. The period of 78.14 days is nearly 10 days longer than that of the previous record-holding Cepheid, S ...
I. Soszyński, D. M. Skowron, A. Udalski, P. Pietrukowicz, M. Gromadzki, M. K. Szymański, J. Skowron, P. Mróz, R. Poleski, S. Kozłowski, P. Iwanek, M. Wrona, K. Ulaczyk, K. Rybicki, M. Mróz   +14 more
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V659 Cen: System Members Updated

The Astronomical Journal
V659 Cen is a classical Cepheid which is part of a multiple system. Previous observations have shown that a hot companion dominates an ultraviolet spectrum and a cooler main-sequence star dominates an XMM-Newton spectrum. The Hubble Space Telescope Space
Nancy Remage Evans, Charles Proffitt, Pierre Kervella, Joanna Kuraszkiewicz, H. Moritz Günther, Richard I. Anderson, Alexandre Gallenne, Antoine Mérand, Boris Trahin, Giordano Viviani, Shreeya Shetye   +10 more
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The Cepheid Distance Scale: A Novel Method for Obtaining Mean Magnitudes from Single-epoch Observations

The Astronomical Journal
We present a novel technique for mapping single-phase observations of Cepheids in any given band into their time-averaged values, using strong priors on the known interrelations of the multiwavelength widths of Cepheid period–luminosity (PL) relations ...
Barry F. Madore, Wendy L. Freedman, Kayla Owens   +2 more
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Stellar Variability and Distance Indicators in the Near-infrared in Nearby Galaxies. II. Pulsating Stars in the Carina Dwarf Spheroidal

The Astronomical Journal
We present homogeneous, near-infrared ( JHK _s bands) time-series observations of the classical Carina dwarf spheroidal (dSph) galaxy to determine accurate and precise distances using the pulsating stars as standard candles.
Chow-Choong Ngeow, Anupam Bhardwaj, Prashant Nishad, Susmita Das   +3 more
doaj   +1 more source

Analysis of pulsating variable stars using the visibility graph algorithm. [PDF]

PLoS One, 2021
Muñoz V, Garcés NE.
europepmc   +1 more source

An omic and multidimensional spatial atlas from serial biopsies of an evolving metastatic breast cancer. [PDF]

Cell Rep Med, 2022
Johnson BE, Creason AL, Stommel JM, Keck JM, Parmar S, Betts CB, Blucher A, Boniface C, Bucher E, Burlingame E, Camp T, Chin K, Eng J, Estabrook J, Feiler HS, Heskett MB, Hu Z, Kolodzie A, Kong BL, Labrie M, Lee J, Leyshock P, Mitri S, Patterson J, Riesterer JL, Sivagnanam S, Somers J, Sudar D, Thibault G, Weeder BR, Zheng C, Nan X, Thompson RF, Heiser LM, Spellman PT, Thomas G, Demir E, Chang YH, Coussens LM, Guimaraes AR, Corless C, Goecks J, Bergan R, Mitri Z, Mills GB, Gray JW.   +45 more
europepmc   +1 more source

The Hubble Constant. [PDF]

Living Rev Relativ, 2015
Jackson N.
europepmc   +1 more source