Chi Boötis, Latinised as χ Boötis, is a single,[11] white-hued star in the northern constellation Boötes, near the eastern constellation border with Corona Borealis. It is faintly visible to the naked eye with an apparent visual magnitude of +5.3.[2] Based upon an annual parallax shift of 13.0 mas as seen from the Earth, it is located about 251 light-years from the Sun. The star is moving closer to the Sun with a radial velocity of −16 km/s.[5]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Boötes |
| Right ascension | 15h 14m 29.15897s[1] |
| Declination | +29° 09′ 51.4630″[1] |
| Apparent magnitude (V) | +5.3074±0.0005[2] |
| Characteristics | |
| Spectral type | A2 V[3] |
| U−B color index | +0.08[4] |
| B−V color index | +0.02[4] |
| Astrometry | |
| Radial velocity (Rv) | −16.0±0.8[5] km/s |
| Proper motion (μ) | RA: −69.688[1] mas/yr Dec.: +28.940[1] mas/yr |
| Parallax (π) | 13.0060 ± 0.1089 mas[2] |
| Distance | 251 ± 2 ly (76.9 ± 0.6 pc) |
| Absolute magnitude (MV) | +0.84[6] |
| Details | |
| Mass | 2.09[7] M☉ |
| Radius | 2.24[8] R☉ |
| Luminosity | 36.8[9] L☉ |
| Surface gravity (log g) | 3.96±0.14[7] cgs |
| Temperature | 9,268±315[7] K |
| Rotational velocity (v sin i) | 84[7] km/s |
| Age | 340[7] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an A-type main-sequence star with a stellar classification of A2 V,[3] which indicates it is generating energy via hydrogen fusion at its core. It is about 340[7] million years old with a projected rotational velocity of 84[7] km/s. The star has double the mass of the Sun,[7] 2.24 times the Sun's radius,[8] and is emitting 37[9] times the Sun's luminosity from its photosphere at an effective temperature of around 9,268 K.[7] It displays an infrared excess at an emission temperature of 65 K, indicating there is a circumstellar disk of dust orbiting the star at a distance of around 123 AU.[8]
References
edit- ^ a b c d Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c 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 Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
- ^ a b Osawa, Kiyoteru (1959), "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of A0 V Stars", Astrophysical Journal, 130: 159, Bibcode:1959ApJ...130..159O, doi:10.1086/146706.
- ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d e f g h i David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ a b c Rhee, Joseph H.; et al. (May 2007), "Characterization of Dusty Debris Disks: The IRAS and Hipparcos Catalogs", The Astrophysical Journal, 660 (2): 1556–1571, arXiv:astro-ph/0609555, Bibcode:2007ApJ...660.1556R, doi:10.1086/509912, S2CID 11879505.
- ^ a b McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- ^ "chi Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-09-09.
{{cite web}}: CS1 maint: postscript (link) - ^ Rodriguez, David R.; Zuckerman, B. (February 2012), "Binaries among Debris Disk Stars", The Astrophysical Journal, 745 (2): 147, arXiv:1111.5618, Bibcode:2012ApJ...745..147R, doi:10.1088/0004-637X/745/2/147, S2CID 73681879.
External links
edit- "chi Boo", Aladin previewer, Centre de Données astronomiques de Strasbourg, retrieved 2017-09-11.