Rotating ellipsoidal variable

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A light curve for Spica, adapted from Tkachenko et al. (2016) AlphaVirLightCurve.png
A light curve for Spica, adapted from Tkachenko et al. (2016)

Rotating ellipsoidal variables are a class of close binary variable star systems whose components are ellipsoidal. They are not eclipsing, but fluctuations in apparent magnitude occur due to changes in the amount of light emitting area visible to the observer. Typical brightness fluctuations do not exceed 0.1 magnitudes. [2]

Contents

The brightest rotating ellipsoidal variable is Spica (α Virginis). [3]

List of variables

List of Rotating ellipsoidal variables [3]
Designation (name)ConstellationDiscovery Apparent magnitude (Maximum) Apparent magnitude (Minimum)Range of magnitudeSpectral typeComment
Spica (α Virginis) Virgo Ruban et al. (2006)0.971.040.07B1 III-IV + B2 VBrightest member; binary
α Trianguli (Mothallah) Triangulum Ruban et al. (2006)3.52 (Hp)3.53 (Hp)0.01F5 III + M
π5 Orionis Orion Ruban et al. (2006)3.663.730.07B2 III + B6 V
b Persei Perseus Ruban et al. (2006)0.971.040.07A2 VBrightest member; binary
68 Cygni (V1809 Cyg) Cygnus 4.985.090.11O7.5 IIIn((f))Hottest member; variability is disputable
π Cassiopeiae Cassiopeia Paunzen & Maitzen (1998) [4] 4.954.970.02A5 V + A5 V
31 Crateris (TY Corvi) Corvus 5.195.230.04B1.5 VUnknown companion
14 Cephei (LZ Cephei) Cepheus Morris (1985) [2] 4.674.710.04O9 III + O9.5 V
HZ Canis Majoris Canis Major 5.285.340.06A0 EuCrSrLong 6.4 year period;binary

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References

  1. Tkachenko, A.; et al. (May 2016), "Stellar modelling of Spica, a high-mass spectroscopic binary with a β Cep variable primary component", Monthly Notices of the Royal Astronomical Society, 458 (2): 1964–1976, arXiv: 1601.08069 , Bibcode:2016MNRAS.458.1964T, doi: 10.1093/mnras/stw255 , S2CID   26945389
  2. 1 2 Morris, S. L. (August 1985). "The ellipsoidal variable stars". The Astrophysical Journal. 295: 143. Bibcode:1985ApJ...295..143M. doi: 10.1086/163359 . eISSN   1538-4357. ISSN   0004-637X. S2CID   121391876.
  3. 1 2 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
  4. Paunzen, E.; Maitzen, H. M. (November 1998). "New variable chemically peculiar stars identifiedin the Hipparcosarchive". Astronomy and Astrophysics Supplement Series. 133 (1): 1–6. Bibcode:1998A&AS..133....1P. doi: 10.1051/aas:1998305 . eISSN   1286-4846. ISSN   0365-0138. S2CID   59046281.