Astronomy:20 Canum Venaticorum

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Short description: Star in the constellation Canes Venatici
20 Canum Venaticorum
AOCVnLightCurve.png
A light curve for AO Canum Venaticorum, plotted from TESS data[1]
Observation data
Equinox J2000.0]] (ICRS)
Constellation Canes Venatici
Right ascension  13h 17m 32.54093s[2]
Declination +40° 34′ 21.3875″[2]
Apparent magnitude (V) +4.715[3]
Characteristics
Spectral type A9 II mF2[4]
B−V color index 0.30[3]
Variable type δ Sct[5]
Astrometry
Radial velocity (Rv)9.32±0.16[6] km/s
Proper motion (μ) RA: −113.761[2] mas/yr
Dec.: +19.858[2] mas/yr
Parallax (π)13.7210 ± 0.1581[2] mas
Distance238 ± 3 ly
(72.9 ± 0.8 pc)
Details
Mass2.43[3] M
Radius4[7] R
Luminosity63[3] L
Surface gravity (log g)2.97[8] cgs
Temperature7,314±42[3] K
Metallicity [Fe/H]0.18[7] dex
Rotational velocity (v sin i)15[9] km/s
Age750[3] Myr
Other designations
20 CVn, AO Canum Venaticorum, BD+41°2380, FK5 494, GC 18000, HD 115604, HIP 64844, HR 5017, SAO 44549[10]
Database references
SIMBADdata

20 Canum Venaticorum is a single[11] variable star in the northern constellation of Canes Venatici, located 238 light years from the Sun. This object has the variable star designation AO Canum Venaticorum; 20 Canum Venaticorum is the Flamsteed designation. It is visible to the naked eye as a faint, white-hued star with a baseline apparent visual magnitude of +4.72.[3] The star is moving further from the Earth with a heliocentric radial velocity of +9 km/s.[6] Eggen (1971) listed this star as a member of the Hyades Stream.[12]

This star has a stellar classification of A9 II mF2, which indicates the hydrogen line matches an A-type bright giant but the metal lines are closer to an F-type star. However, it does not appear to be an Am star as the Calcium K line is normal.[4] Earlier, Morgan and Abt (1972) assigned it a giant star class of F3 III.[13] It is classified as a Delta Scuti type variable star with a single radial pulsation mode providing the best fit to the observed variation.[5] Its brightness varies from magnitude +4.70 to +4.75 with a period of 2.92 hours.[14]

20 Canum Venaticorum is 750[3] million years old with 2.43[3] times the mass of the Sun and 4[7] time the Sun's radius. It is radiating 63[3] times the Sun's luminosity from its photosphere at an effective temperature of 7,314 K.[3]

References

  1. "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html. 
  2. 2.0 2.1 2.2 2.3 2.4 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal 150 (3): 88, doi:10.1088/0004-6256/150/3/88, Bibcode2015AJ....150...88L. 
  4. 4.0 4.1 Gray, R. O. et al. (2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars", The Astronomical Journal 121 (4): 2148, doi:10.1086/319956, Bibcode2001AJ....121.2148G. 
  5. 5.0 5.1 Chadid, M. et al. (August 2001), "20 CVn: A monoperiodic radially pulsating delta Scuti star", Astronomy and Astrophysics 375: 113–121, doi:10.1051/0004-6361:20010809, Bibcode2001A&A...375..113C. 
  6. 6.0 6.1 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  7. 7.0 7.1 7.2 Massarotti, Alessandro et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity", The Astronomical Journal 135 (1): 209–231, doi:10.1088/0004-6256/135/1/209, Bibcode2008AJ....135..209M. 
  8. Adamczak, Jens; Lambert, David L. (August 2014), "Carbon and Oxygen Abundances across the Hertzsprung Gap", The Astrophysical Journal 791 (1): 12, doi:10.1088/0004-637X/791/1/58, 58, Bibcode2014ApJ...791...58A. 
  9. Royer, F. et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics 393: 897–911, doi:10.1051/0004-6361:20020943, Bibcode2002A&A...393..897R. 
  10. "20 CVn". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=20+CVn. 
  11. Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E. 
  12. Eggen, O. J. (December 1971), "Luminosities and Motions of the F-Type Stars. I. Luminosity and Metal Abundance Indices for Disk Population Stars", Publications of the Astronomical Society of the Pacific 83 (496): 741, doi:10.1086/129211, Bibcode1971PASP...83..741E. 
  13. Morgan, W. W.; Abt, H. A. (February 1972), "The spectral classification of the F stars of intermediate luminosity", Astronomical Journal 77: 35–37, doi:10.1086/111242, Bibcode1972AJ.....77...35M. 
  14. Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80–88, doi:10.1134/s1063772917010085, Bibcode2017ARep...61...80S.