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ChaHα8

ChaHα8 with the Spitzer Space Telescope
Observation data
Epoch J2000       Equinox J2000
Constellation Chamaeleon
Right ascension 11h 07m 46.091s [1]
Declination −77° 40′ 08.92″ [1]
Apparent magnitude (V) 20.1 [2]
Characteristics
Spectral type M5.75–M6.5 [3]
Astrometry
Proper motion (μ) RA: -23.455  mas/ yr [1]
Dec.: 0.453  mas/ yr [1]
Parallax (π)5.0899 ± 0.0792  mas [1]
Distance641 ± 10  ly
(196 ± 3  pc)
Orbit [4]
Period (P)1895±132  d
Semi-major axis (a)1.02±0.061.17±0.07  AU
Eccentricity (e)0.59±0.22
Periastron epoch (T)2453163±214  JD
Argument of periastron (ω)
(secondary)
106±26°
Semi-amplitude (K1)
(primary)
2.433±0.44 km/s
Details
ChaHα8 A
Mass0.07–0.10 [3]  M
Temperature2910–3024 [3]  K
Rotational velocity (v sin i)15.5±2.6 [3] km/s
Age~3 [3]  Myr
ChaHα8 B
Mass25±731±8 [4]  MJup
Other designations
2MASS J11074610-7740089, CHSM 10837, SBC9 3352, Cha Hα 8 [2]
Database references
SIMBAD data

ChaHα8 (also written ChaHa8 when Greek letters are unavailable) is a binary brown dwarf about 640 light-years (200 parsecs) from Earth in the constellation Chamaeleon. The designation indicates that it is in the Chamaeleon I star-forming region and that it displays hydrogen-alpha emission. It was discovered in 2000. [5]

It was found in 2007 to have a low-mass substellar companion in orbit around it via radial velocity observations. [3] The companion has a mass of 25–31 Jupiter masses, and the pair orbit each other with a period of 5.2 years and an eccentricity of 0.59. [4]

References

  1. ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211. Bibcode: 2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940. S2CID  244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b "CHSM 10837". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 29 November 2016.
  3. ^ a b c d e f Joergens, V.; A. Mueller (2007). "16–20 Jupiter mass RV companion orbiting the brown dwarf candidate ChaHa8". The Astrophysical Journal. 666 (2). arXiv: 0707.3744. Bibcode: 2007ApJ...666L.113J. doi: 10.1086/521825. S2CID  119140521.
  4. ^ a b c Joergens, V.; Müller, A.; Reffert, S. (2010). "Improved radial velocity orbit of the young binary brown dwarf candidate Cha Hα 8". Astronomy and Astrophysics. 521 (A24): A24. arXiv: 1006.2383. Bibcode: 2010A&A...521A..24J. doi: 10.1051/0004-6361/201014853. S2CID  54989533.
  5. ^ Comerón, F.; Neuhäuser, R.; Kaas, A. A. (2000). "Probing the brown dwarf population of the Chamaeleon I star forming region". Astronomy and Astrophysics. 359: 269–288. Bibcode: 2000A&A...359..269C.

External links