DI Chamaeleontis

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DI Chamaeleontis
Smoke ring for a halo.jpg
Image showing DI Cha A and B, each of which is also an even closer binary, and the surrounding nebulosity.
Credit: ESA/Hubble & NASA Acknowledgement: Judy Schmidt (geckzilla.org).
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[1] mas
Distanceapprox. 700 ly
(approx. 220 pc)
Details[5]
Aa
Mass1.7 M
Radius2.00 R
Luminosity4.7 L
Temperature6,030 K
Age7.1 Myr
Ba/Bb
Mass0.18 M
Radius1.13 R
Luminosity0.11 L
Temperature3,130 K
Age3.0 Myr
Other designations
DI Cha, HIP 54365, CD−76°486, WDS J11073-7738, AAVSO 1104-77
Database references
SIMBADdata

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 star 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" away, of spectral type M6.[10]

References[edit]

  1. ^ a b c d e Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  2. ^ 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. Bibcode:1985SAAOC...9...55K.
  3. ^ 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.
  4. ^ 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.
  5. ^ 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.
  6. ^ 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.
  7. ^ 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.
  8. ^ Reipurth, Bo; Zinnecker, Hans (1993). "Visual binaries among pre-main sequence stars". Astronomy and Astrophysics. 278: 81. Bibcode:1993A&A...278...81R.
  9. ^ 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.
  10. ^ 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.