W Virginis variable

W Virginis variables are a subclass of Type II Cepheids which exhibit pulsation periods between 10–20 days,[1] and are of spectral class F6 – K2.[2][3]

They were first recognized as being distinct from classical Cepheids by Walter Baade in 1942, in a study of Cepheids in the Andromeda Galaxy that proposed that stars in that galaxy were of two populations.[4]

See also

References

  1. Wallerstein, G., "The Cepheids of Population II and Related Stars", Publications of the Astronomical Society of the Pacific, 114 p.689–699 (2002)
  2. W. Strohmeier, Variable Stars, Pergamon (1972)
  3. Soszyński, I.; Udalski, A.; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Wyrzykowski, Ł.; Szewczyk, O.; Ulaczyk, K.; Poleski, R. "The Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. II.Type II Cepheids and Anomalous Cepheids in the Large Magellanic Cloud", Acta A., vol 58 (2008)
  4. Webb, Stephen, Measuring the Universe: The Cosmological Distance Ladder, Springer, (1999)

External links


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