Astronomy:Chi Boötis

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Short description: Star in the constellation Boötes
χ Boötis
Location of χ Boötis (circled in red)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Boötes[1]
Right ascension  15h 14m 29.159s[2]
Declination +29° 09′ 51.47″[2]
Apparent magnitude (V) 5.28[1]
Characteristics
Evolutionary stage main sequence[3]
Spectral type A2 V[4]
U−B color index +0.08[5]
B−V color index +0.02[5]
Astrometry
Radial velocity (Rv)−16.0±0.8[6] km/s
Proper motion (μ) RA: −69.512[2] mas/yr
Dec.: +28.662[2] mas/yr
Parallax (π)13.3668 ± 0.0584[2] mas
Distance244 ± 1 ly
(74.8 ± 0.3 pc)
Absolute magnitude (MV)+0.84[1]
Details
Mass2.09[7] M
Radius2.24[8] R
Luminosity36.8[9] L
Surface gravity (log g)3.96±0.14[7] cgs
Temperature9,268±315[7] K
Rotational velocity (v sin i)84[7] km/s
Age340[7] Myr
Other designations
χ Boo, 48 Boötis, BD+29°2640, FK5 3204, GC 20495, HD 135502, HIP 74596, HR 5676, SAO 83729[10]
Database references
SIMBADdata

Chi Boötis is a single,[11] white-hued star in the northern constellation Boötes, near the eastern constellation border with Corona Borealis. Its name is a Bayer designation that is Latinised from χ Boötis, and abbreviated Cho Boo or χ Boo. This star is faintly visible to the naked eye with an apparent visual magnitude of +5.3.[1] Based upon an annual parallax shift of 13.4 mas as seen from the Earth, it is located approximately 244 light-years (75 pc) from Earth. The star is moving closer to the Sun with a radial velocity of −16 km/s.[6]

This is an A-type main-sequence star with a stellar classification of A2 V,[4] 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 astronomical unit|AU.[8]

References

  1. 1.0 1.1 1.2 1.3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A.  XHIP record for this object at VizieR.
  2. 2.0 2.1 2.2 2.3 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940.  Gaia DR3 record for this source at VizieR.
  3. Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy and Astrophysics 537: A120. doi:10.1051/0004-6361/201117691. Bibcode2012A&A...537A.120Z. 
  4. 4.0 4.1 Cowley, A. et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal 74: 375–406, doi:10.1086/110819, Bibcode1969AJ.....74..375C. 
  5. 5.0 5.1 Osawa, Kiyoteru (1959), "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of A0 V Stars", Astrophysical Journal 130: 159, doi:10.1086/146706, Bibcode1959ApJ...130..159O. 
  6. 6.0 6.1 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, doi:10.1051/0004-6361/201219219, A61, Bibcode2012A&A...546A..61D. 
  7. 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 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, doi:10.1088/0004-637X/804/2/146, Bibcode2015ApJ...804..146D. 
  8. 8.0 8.1 8.2 Rhee, Joseph H. et al. (May 2007), "Characterization of Dusty Debris Disks: The IRAS and Hipparcos Catalogs", The Astrophysical Journal 660 (2): 1556–1571, doi:10.1086/509912, Bibcode2007ApJ...660.1556R. 
  9. 9.0 9.1 McDonald, I. et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society 427 (1): 343–57, doi:10.1111/j.1365-2966.2012.21873.x, Bibcode2012MNRAS.427..343M. 
  10. "chi Boo". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=chi+Boo. 
  11. Rodriguez, David R.; Zuckerman, B. (February 2012), "Binaries among Debris Disk Stars", The Astrophysical Journal 745 (2): 147, doi:10.1088/0004-637X/745/2/147, Bibcode2012ApJ...745..147R.