DI Chamaeleontis
 Image showing DI Cha A and B, each of which is also an even closer binary, and the surrounding nebulosity. | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Chamaeleon |
| Right ascension | 11h 07m 20.72163s[1] |
| Declination | −77° 38′ 07.2903″[1] |
| Apparent magnitude (V) | 10.655[2] |
| Characteristics | |
| Spectral type | G0e[3] |
| U−B color index | +0.630[2] |
| B−V color index | +1.144[2] |
| Variable type | T Tau[4] |
| Astrometry | |
| Proper motion (μ) | RA: −24.61[1] mas/yr Dec.: 3.45[1] mas/yr |
| Parallax (π) | 4.49 ± 1.59 mas[1] |
| Distance | approx. 700 ly (approx. 220 pc) |
| Details[5] | |
| Aa | |
| Mass | 1.7 M☉ |
| Radius | 2.00 R☉ |
| Luminosity | 4.7 L☉ |
| Temperature | 6,030 K |
| Age | 7.1 Myr |
| Ba/Bb | |
| Mass | 0.18 M☉ |
| Radius | 1.13 R☉ |
| Luminosity | 0.11 L☉ |
| Temperature | 3,130 K |
| Age | 3.0 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
DI Chamaeleontis, also known as Hen 3-593 or HIP 54365, is a quadruple star system in the constellation Chamaeleon. The system is roughly 700 light years from Earth.
DI Cha is a variable star of the T Tauri type, young stellar objects just approaching the main sequence. It varies erratically between visual magnitudes 10.65 and 10.74.[4] Although it is visually faint, it was noticed because of the prominent emission lines in its spectrum.[6]
In 1977, DI Cha was observed to have a much fainter companion.[7] The separation was later measured at 4.6", approximately 644 astronomical units (AU).[8] The B component was discovered to be a pair of stars separated by only 0.066", about 10 AU,[9] both with spectral type M5.5.[10] Finally, the variable primary star was found to have a faint companion 0.2" (therefore ~30 AU) away, of spectral type M6.[10]
References[edit]
- ^ a b c d e Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- ^ a b c Kilkenny, D.; Whittet, D. C. B.; Davies, J. K.; Evans, A.; Bode, M. F.; Robson, E. I.; Banfield, R. M. (1985). "Optical and infrared photometry of southern early-type shell stars and pre-main-sequence variables". In Its South African Astronomical Observatory Circular No. 9 P 55-86 (SEE N86-18271 08-89). 9: 55. Bibcode:1985SAAOC...9...55K.
- ^ Torres, C. A. O.; Quast, G. R.; Da Silva, L.; de la Reza, R.; Melo, C. H. F.; Sterzik, M. (2006). "Search for associations containing young stars (SACY). I. Sample and searching method". Astronomy and Astrophysics. 460 (3): 695. arXiv:astro-ph/0609258. Bibcode:2006A&A...460..695T. doi:10.1051/0004-6361:20065602. S2CID 16080025.
- ^ a b 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. Bibcode:2009yCat....102025S.
- ^ Daemgen, S.; Petr-Gotzens, M. G.; Correia, S.; Teixeira, P. S.; Brandner, W.; Kley, W.; Zinnecker, H. (2013). "Protoplanetary disk evolution and stellar parameters of T Tauri binaries in Chamaeleon I". Astronomy & Astrophysics. 554: A43. arXiv:1304.1150. Bibcode:2013A&A...554A..43D. doi:10.1051/0004-6361/201321220. S2CID 59440639.
- ^ Henize, Karl G. (1963). "Emission-Line Stars in an Obscured Region in Chamaeleon". Astronomical Journal. 68: 280. Bibcode:1963AJ.....68S.280H. doi:10.1086/109141.
- ^ Schwartz, R. D. (1977). "A survey of southern dark clouds for Herbig-Haro objects and H-alpha emission stars". Astrophysical Journal Supplement Series. 35: 161. Bibcode:1977ApJS...35..161S. doi:10.1086/190473.
- ^ Reipurth, Bo; Zinnecker, Hans (1993). "Visual binaries among pre-main sequence stars". Astronomy and Astrophysics. 278: 81. Bibcode:1993A&A...278...81R.
- ^ Lafrenière, David; Jayawardhana, Ray; Brandeker, Alexis; Ahmic, Mirza; Van Kerkwijk, Marten H. (2008). "A Multiplicity Census of Young Stars in Chamaeleon I". The Astrophysical Journal. 683 (2): 844–861. arXiv:0803.0561. Bibcode:2008ApJ...683..844L. doi:10.1086/590239. S2CID 2998049.
- ^ a b Schmidt, T. O. B.; Vogt, N.; Neuhäuser, R.; Bedalov, A.; Roell, T. (2013). "New companions in the stellar systems of DI Cha, Sz 22, CHXR 32, and Cha Hα 5 in the Chamaeleon I star-forming region". Astronomy & Astrophysics. 557: A80. arXiv:1307.1082. Bibcode:2013A&A...557A..80S. doi:10.1051/0004-6361/201220660. S2CID 67802847.
