Astronomy:Z Chamaeleontis
From HandWiki
Short description: Variable star in the constellation Chamaeleon
Observation data Equinox J2000.0]] (ICRS) | |
---|---|
Constellation | Chamaeleon |
Right ascension | 08h 07m 27.7517s |
Declination | −76° 32′ 00.6650″ |
Apparent magnitude (V) | 11.5 - 16.2[2] |
Characteristics | |
Spectral type | DA? + M5.5e[3] |
Variable type | SU UMa + Algol[4] |
Astrometry | |
Radial velocity (Rv) | −20[5] km/s |
Proper motion (μ) | RA: −33.650[6] mas/yr Dec.: +56.883[6] mas/yr |
Parallax (π) | 8.2805 ± 0.074[6] mas |
Distance | 394 ± 4 ly (121 ± 1 pc) |
Orbit | |
Primary | white dwarf |
Companion | red dwarf |
Period (P) | 1.79 d[7] |
Eccentricity (e) | 0[7] |
Inclination (i) | 81.8±0.1[8]° |
Semi-amplitude (K1) (primary) | 105[7] km/s |
Details | |
white dwarf | |
Mass | 1[8] M☉ |
Radius | 0.013/0.48 R☉ |
Luminosity | 0.007/0.017 L☉ |
Temperature | 14,700/3100 K |
red dwarf | |
Other designations | |
Z Cha, 2E 1942, SBC9 505, CSV 1244, 2MASS J08072774-7632006, SON 4893, 2E 0808.8-7622, 1RXS J080728.8-763157, AAVSO 0809-76 | |
Database references | |
SIMBAD | data |
Z Chamaeleontis (abbreviated Z Cha) is a dwarf nova variable star system approximately 377 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.[9]
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.
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. doi:10.1093/mnras/219.3.629. Bibcode: 1986MNRAS.219..629W.
- ↑ 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. doi:10.1086/165905. ISSN 0004-637X. Bibcode: 1988ApJ...324..411W.
- ↑ 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. doi:10.1134/S1063772917010085. ISSN 1063-7729. Bibcode: 2017ARep...61...80S.
- ↑ 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. ISSN 0365-0138. Bibcode: 1995A&AS..114..269D.
- ↑ 6.0 6.1 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ 7.0 7.1 7.2 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. doi:10.1093/mnras/225.3.551. ISSN 0035-8711. Bibcode: 1988ApJ...324..411W.
- ↑ 8.0 8.1 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. doi:10.1093/mnras/stw1120. ISSN 0035-8711. Bibcode: 2016MNRAS.460.2526O.
- ↑ 9.0 9.1 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. doi:10.1088/0004-637X/703/1/109. Bibcode: 2009ApJ...703..109D. http://sedici.unlp.edu.ar/handle/10915/82785.
Coordinates: 08h 07m 27.75s, −76° 32′ 00.7″
Original source: https://en.wikipedia.org/wiki/Z Chamaeleontis.
Read more |