A0620-00

A0620-00

A visual band light curve for V616 Monocerotis, adapted from van Grunsven et al. (2017)[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Monoceros
Right ascension 06h 22m 44.542s[2]
Declination −00° 20′ 44.29″[2]
Apparent magnitude (V) 11.2[3]
Characteristics
Evolutionary stage Black hole + main sequence[4]
Spectral type K2 V[5]
Variable type X-ray nova, Ellipsoidal[6]
Astrometry
Radial velocity (Rv)−5±12[7] km/s
Proper motion (μ) RA: −0.439 mas/yr[2]
Dec.: −5.138 mas/yr[2]
Parallax (π)0.6969 ± 0.1168 mas[2]
Distanceapprox. 4,700 ly
(approx. 1,400 pc)
Orbit
Period (P)7.75234 ± 0.00010[7] hr
Inclination (i)50.98 ± 0.87[4]°
Periastron epoch (T)JD 2446082.7481 ± 0.0008[7]
Semi-amplitude (K1)
(primary)		457 ± 8[7] km/s
Details
Black hole
Mass5.86±1.24[8] M☉
Star
Mass0.34±0.03[8] M☉
Radius1.057[9] R☉
Luminosity0.44[9] L☉
Surface gravity (log g)5.0[5] cgs
Temperature5,000[5] K
Metallicity [Fe/H]0.0[5] dex
Rotational velocity (v sin i)83.8±1.9[5] km/s
Other designations
1A 0620-00, INTREF 297, Nova Mon 1917, Nova Mon 1975, Mon X-1, V616 Mon[3]
Database references
SIMBADdata

A0620-00 (abbreviated from 1A 0620-00) is a binary star system in the constellation of Monoceros, with an apparent magnitude of 11.2.

A0620-00 consists of two objects. The first object is a K-type main-sequence star.[4][5] The second object cannot be seen, but based on its calculated mass of about 6 M☉,[8][4] it is too massive to be a neutron star and must therefore be a stellar-mass black hole.[7] The two objects orbit each other every 7.75 hours.[7] At a distance of roughly 3,300 light-years (1,000 parsecs) away, the black hole of A0620-00 would be one of the nearest known black holes to the Solar System, closer than GRO J1655-40.[10]

This image of A0620-00 was created from Sloan Digital Sky Survey data in visible and infrared light (filters u,g,i,z) and spans roughly 8 arcminutes.

A0620-00 has undergone two X-ray outbreaks. The first one was in 1917.[11] The second burst, in 1975, was detected by the Ariel 5 satellite.[12] During that time, A0620-00 was the brightest X-ray point source.[7] It is now classified as an X-ray nova.[7] Its black hole nature was determined in 1986.[7]

The black hole in A0620-00 pulls matter from the K-type star into an accretion disk.[4] The accretion disk emits significant amounts of visible light and X-rays. Because the K-type star has been pulled into an ellipsoidal shape, the amount of surface area visible, and thus the apparent brightness, changes from the Earth's perspective. A0620-00 also bears the variable star designation V616 Monocerotis.[6]

  1. ^ Cite error: The named reference vG2017 was invoked but never defined (see the help page).
  2. ^ a b c d Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  3. ^ a b "1A 0620-00". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 26 August 2017.
  4. ^ a b c d e Cantrell, Andrew G.; Bailyn, Charles D.; Orosz, Jerome A.; McClintock, Jeffrey E.; Remillard, Ronald A.; Froning, Cynthia S.; Neilsen, Joseph; Gelino, Dawn M.; Gou, Lijun (2010). "The Inclination of the Soft X-Ray Transient A0620-00 and the Mass of its Black Hole". The Astrophysical Journal. 710 (2): 1127–1141. arXiv:1001.0261. Bibcode:2010ApJ...710.1127C. doi:10.1088/0004-637X/710/2/1127. S2CID 33906909.
  5. ^ a b c d e f Zheng, Wan-Min; Wu, Qiaoya; Wu, Jianfeng; Wang, Song; Sun, Mouyuan; Guo, Jing; Liu, Junhui; Yi, Tuan; Zhang, Zhi-Xiang; Gu, Wei-Min; Wang, Junfeng; Gou, Lijun; Liu, Jifeng; Callanan, Paul J.; Ho, Luis C.; Longa-Peña, Penélope; Orosz, Jerome A.; Reynolds, Mark T. (2022), "The Disk Veiling Effect of the Black Hole Low-mass X-Ray Binary A0620-00", The Astrophysical Journal, 925 (1): 83, arXiv:2112.07842, Bibcode:2022ApJ...925...83Z, doi:10.3847/1538-4357/ac4332, S2CID 245144462
  6. ^ 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.
  7. ^ a b c d e f g h i McClintock, J. E.; Remillard, R. A. (1986). "The black hole binary A0620-00". Astrophysical Journal. 308: 110–122. Bibcode:1986ApJ...308..110M. doi:10.1086/164482.
  8. ^ a b c Van Grunsven, Theo F. J.; Jonker, Peter G.; Verbunt, Frank W. M.; Robinson, Edward L. (2017), "The mass of the black hole in 1A 0620-00, revisiting the ellipsoidal light curve modelling", Monthly Notices of the Royal Astronomical Society, 472 (2): 1907, arXiv:1708.08209, Bibcode:2017MNRAS.472.1907V, doi:10.1093/mnras/stx2071
  9. ^ a b Stassun, Keivan G.; et al. (1 October 2019), "The Revised TESS Input Catalog and Candidate Target List", The Astronomical Journal, 158 (4): 138, arXiv:1905.10694, Bibcode:2019AJ....158..138S, doi:10.3847/1538-3881/ab3467, hdl:1721.1/124721, ISSN 0004-6256, S2CID 166227927.
  10. ^ Foellmi, Cédric (2009). "What is the closest black hole to the Sun?". New Astronomy. 14 (8): 674–691. arXiv:0812.4232. Bibcode:2009NewA...14..674F. doi:10.1016/j.newast.2009.04.003. S2CID 12843219.
  11. ^ Eachus, L. J.; Wright, E. L.; Liller, W. (1976). "Optical observations of the recurrent nova associated with A0620-00 - 1917-1975". Astrophysical Journal. 203: L17–L19. Bibcode:1976ApJ...203L..17E. doi:10.1086/182009.
  12. ^ Elvis, M.; Page, C. G.; Pounds, K. A.; Ricketts, M. J.; Turner, M. J. L. (1975). "Discovery of powerful transient X-ray source A0620-00 with Ariel V Sky Survey Experiment". Nature. 257 (5528): 656–657. Bibcode:1975Natur.257..656E. doi:10.1038/257656a0. S2CID 4160399.