Z Chamaeleontis
Z Chamaeleontis (abbreviated Z Cha) is a dwarf nova variable star system approximately 394 light-years away from the Sun, where two stars orbit each other every 1.78 hours. The system comprises an eclipsing white dwarf and red dwarf and possibly a yet unconfirmed third low-mass substellar companion.
![](//upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Diagram_of_the_%28possible%29_Z_Chamaeleontis_Star_system.png/220px-Diagram_of_the_%28possible%29_Z_Chamaeleontis_Star_system.png)
Possible makeup of the Z Chamaeleontis Star system.
Substellar companion
Dai et al. (2009) invoke the presence of a third object to explain orbital period variations with an apparent periodicity of roughly 28 years. The third body could yield a minimum mass 20 times greater than Jupiter and be located 9.9 Astronomical Units away from the dwarf nova, being likely a low-mass brown dwarf.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Diagram_of_the_%28possible%29_Z_Chamaeleontis_Star_system.png/220px-Diagram_of_the_%28possible%29_Z_Chamaeleontis_Star_system.png)
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b (unconfirmed) | ≥20 MJ | 9.9 | 28 | ≤0.2 | — | — |
See also
References
- ^ Wood, Janet; Horne, Keith; Berriman, Graham; Wade, R.; O'Donoghue, D.; Warner, B. (April 1986). "High-speed photometry of the dwarf nova Z Cha in quiescence". Monthly Notices of the Royal Astronomical Society. 219 (3): 629–655. Bibcode:1986MNRAS.219..629W. doi:10.1093/mnras/219.3.629.
- ^ Watson, C. L.; Henden, A. A.; Price, A. (May 2006). "The International Variable Star Index (VSX)". Society for Astronomical Sciences Annual Symposium. 25: 47. Bibcode:2006SASS...25...47W.
- ^ Wade, Richard A.; Horne, Keith (January 1988). "The radial velocity curve and peculiar TiO distribution of the red secondary star in Z Chamaeleontis". The Astrophysical Journal. 324: 411. Bibcode:1988ApJ...324..411W. doi:10.1086/165905. eISSN 1538-4357. ISSN 0004-637X.
- ^ Samus’, N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (January 2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. ISSN 1063-7729. S2CID 255195566.
- ^ Duflot, M.; Figon, P.; Meyssonnier, N. (December 1995). "Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue". Astronomy and Astrophysics Supplement Series. 114: 269. Bibcode:1995A&AS..114..269D. ISSN 0365-0138.
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ Marsh, T. R.; Horne, Keith; Shipman, H. L. (April 1987). "A spectrophotometric study of the emission lines in the quiescent dwarf nova Z Chamaeleontis". Monthly Notices of the Royal Astronomical Society. 225 (3): 551–580. Bibcode:1988ApJ...324..411W. doi:10.1093/mnras/225.3.551. eISSN 1365-2966. ISSN 0035-8711.
- ^ Otulakowska-Hypka, Magdalena; Olech, Arkadiusz; Patterson, Joseph (12 May 2016). "Statistical analysis of properties of dwarf novae outbursts". Monthly Notices of the Royal Astronomical Society. 460 (3): 2526–2541. arXiv:1605.02937. Bibcode:2016MNRAS.460.2526O. doi:10.1093/mnras/stw1120. eISSN 1365-2966. ISSN 0035-8711.
- ^ Dai; Qian, Shengbang; Lajús, Eduardo FernáNdez (26 August 2009). "Evidence of a Brown Dwarf in the Eclipsing Dwarf Nova Z Chamaeleonis". The Astrophysical Journal. 703 (1): 109–113. Bibcode:2009ApJ...703..109D. doi:10.1088/0004-637X/703/1/109.