LS 5039

LS 5039

A broad-band optical light curve for V479 Scuti, adapted from Sarty et al. (2011)[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Scutum
Right ascension	18^h 26^m 15.0568^s[2]
Declination	−14° 50′ 54.242″[2]
Apparent magnitude (V)	11.27[3]
Characteristics
Spectral type	O(f)N6.5V + Black hole[4]
Astrometry
Radial velocity (Rv)	17.2 ± 0.7[4] km/s
Proper motion (μ)	RA: 6.826[2] mas/yr Dec.: −8.515[2] mas/yr
Distance	8200±300[4] ly (2500±100[4] pc)
Orbit[4]
Period (P)	3.90603 ± 0.00017 d
Eccentricity (e)	0.31 ± 0.04
Inclination (i)	24.9 ± 2.8°
Periastron epoch (T)	HJD 2451943.09 ± 0.10
Argument of periastron (ω) (secondary)	226 ± 8°
Semi-amplitude (K1) (primary)	19.4 ± 0.9 km/s
Details[4]
O star
Mass	22.9+3.4 −2.9 M☉
Radius	9.3+0.7 −0.6 R☉
Luminosity	182000 L☉
Surface gravity (log g)	3.85 cgs
Temperature	39000 K
Rotational velocity (v sin i)	113 km/s
Black hole
Mass	3.7+1.3 −1.0 M☉
Radius	Probably 10.93 km
Other designations
V479 Sct, TYC 5702-1197-1, 2MASS J18261505-1450542[5]
Database references
SIMBAD	data

LS 5039 is a binary system in the constellation of Scutum. It has an apparent magnitude of 11.27,[3] and it is about 8,200 light-years away.[4]

LS 5039 consists of a massive O-type main-sequence star, and a compact object (likely a black hole)[4] that emits HE (high energy) and VHE (very high energy) gamma rays. It is one of the only three known star systems of this kind, together with LS I +61 303 and PSR B1259-63. The two objects orbit each other every 3.9 days, along a moderately eccentric orbit.[4] Additionally, it is one of the few massive X-ray binaries known to be associated with radio emission.[6]

References

1. Sarty, Gordon E.; Szalai, Tamás; Kiss, László; Matthews, Jaymie M.; Wu, Kinwah; Kuschnig, Rainer; Guenther, David B.; Moffat, Anthony F. J.; Rucinski, Slavek M.; Sasselov, Dimitar; Weiss, Werner W.; Huziak, Richard; Johnston, Helen M.; Phillips, Andre; Ashley, Michael C. B. (February 2011). "The γ-ray binary LS 5039: mass and orbit constraints from MOST observations". Monthly Notices of the Royal Astronomical Society. 411 (2): 1293–1300. arXiv:1009.5150. Bibcode:2011MNRAS.411.1293S. doi:10.1111/j.1365-2966.2010.17757.x. S2CID 13234345.
2. Gaia Collaboration (2016). "Gaia Data Release 1". Astronomy & Astrophysics. 595: A2. arXiv:1609.04172. Bibcode:2016A&A...595A...2G. doi:10.1051/0004-6361/201629512. S2CID 1828208.
3. Zacharias, N. (2012). "The fourth US Naval Observatory CCD Astrograph Catalog (UCAC4)". VizieR On-line Data Catalog. Bibcode:2012yCat.1322....0Z.
4. Casares, J; Ribo, M; Ribas, I; Paredes, J. M; Marti, J; Herrero, A (2005). "A possible black hole in the γ-ray microquasar LS 5039". Monthly Notices of the Royal Astronomical Society. 364 (3): 899–908. arXiv:astro-ph/0507549. Bibcode:2005MNRAS.364..899C. doi:10.1111/j.1365-2966.2005.09617.x. S2CID 8393701.
5. "V* V479 Sct". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2 May 2018.
6. Trigueros Páez, E.; Barbá, R. H.; Negueruela, I.; Maíz Apellániz, J.; Simón-Díaz, S.; Holgado, G. (2021). "MONOS: Multiplicity of Northern O-type Spectroscopic systems". Astronomy & Astrophysics. 655: A4. arXiv:2106.08865. doi:10.1051/0004-6361/202141018. S2CID 235446900.

External links

• Discovery of Very High Energy Gamma Rays Associated with an X-ray Binary (Science Express) July 7, 2005
• Astronomers Discovery Very High Energy Gamma-ray Emission From Microquasar (ScienceDaily) May 19, 2006

See also

• LS I +61 303, the only other known VHE gamma ray producing system