V4641 Sagittarii

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V4641 Sagittarii
V4641SgrLightCurve.png
A visual band light curve for V4641 Sagittarii, adapted from Goranskij (2001) [1]
Observation data
Epoch J2000.0        Equinox J2000.0
Constellation Sagittarius
Right ascension 18h 19m 21.63427s [2]
Declination −25° 24′ 25.8493″ [2]
Apparent magnitude  (V)9.0 - 14.0 [3]
Characteristics
Spectral type B9III [4]
Variable type HMXB/BHXB/XN+ELL+E [3]
Astrometry
Proper motion (μ)RA: −0.734 [2]   mas/yr
Dec.: +0.418 [2]   mas/yr
Parallax (π)0.1510 ± 0.0413  mas [2]
Distance 20,200 ± 2,300 [4]   ly
Orbit [4]
Period (P)2.81730 d
Semi-major axis (a)17.5±1.0  R☉
Inclination (i)72.3±4.1°
Periastron epoch (T)2,452,423.647
Semi-amplitude (K2)
(secondary)		211.3±1.0 km/s
Details [4]
Black hole
Mass 6.4±0.6  M☉
Stellar companion
Mass 2.9±0.4  M☉
Radius 5.3±0.3  R☉
Surface gravity (log g)3.5±0.1  cgs
Temperature 10,250±300  K
Rotational velocity (v sin i)100.9±0.8 km/s
Other designations
V4641 Sgr, GSC  06848-03786, 2MASS J18192163-2524258 [5]
Database references
SIMBAD data

V4641 Sagittarii is a variable X-ray binary star system in the constellation Sagittarius. It is the source of one of the fastest superluminal jets in the Milky Way galaxy.

In 1999 a violent X-ray outburst revealed it to contain a black hole. [6] At the time, it was considered to be the closest known black hole to Earth, at a distance of approximately 1,600 light-years (490  pc ). Later observations showed it to be much farther away, reported in 2001 to be between 7.4 and 12.31  kpc , [7] 6.2 kpc in 2014, [4] and around 6.6 kpc according to its Gaia Data Release 2 parallax. [2]

The star in the binary system is a late B class giant with a mass about three times that of the Sun. It orbits a black hole about twice as massive every 2.8 days. The star is distorted, which causes variations in its brightness as it orbits and rotates. It is also slightly eclipsed by an accretion disc around the black hole. The system usually does not produce a significant amount of x-rays, but undergoes outbursts when the x-ray luminosity increases due to accretion onto the black hole driving superluminal jets. [7]

V4641 Sgr is a source of ultra-high-energy gamma rays. [8]

Related Research Articles

Ross 154 is a star in the southern zodiac constellation of Sagittarius. It has an apparent visual magnitude of 10.44, making it much too faint to be seen with the naked eye. At a minimum, viewing Ross 154 requires a telescope with an aperture of 6.5 cm (3 in) under ideal conditions. The distance to this star can be estimated from parallax measurements, which places it at 9.71 light-years away from Earth. It is the nearest star in the southern constellation Sagittarius, and one of the nearest stars to the Sun.

<span class="mw-page-title-main">Galactic Center</span> Rotational center of the Milky Way galaxy

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<span class="mw-page-title-main">V1494 Aquilae</span> Nova seen in 1999 in the constellation of Aquila

V1494 Aquilae or Nova Aquilae 1999 b was a nova which occurred during 1999 in the constellation Aquila and reached a brightness of magnitude 3.9 on 2 December 1999. making it easily visible to the naked eye. The nova was discovered with 14×100 binoculars by Alfredo Pereira of Cabo da Roca, Portugal at 18:50 UT on 1 December 1999, when it had a visual magnitude of 6.0.

<span class="mw-page-title-main">W Sagittarii</span> Star in the constellation Sagittarius

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<span class="mw-page-title-main">Mu Sagittarii</span> Multiple star system in the constellation Sagittarius

Mu Sagittarii is a multiple star system in the constellation of Sagittarius. The brightest component, a blue supergiant designated Mu Sagittarii Aa, is formally named Polis. The system is 5,000 light-years from the Sun and is part of the Sgr OB1 stellar association.

<span class="mw-page-title-main">Upsilon Sagittarii</span> Binary star system in the constellation Sagittarius

Upsilon Sagittarii is a spectroscopic binary star system in the constellation Sagittarius. Upsilon Sagittarii is the prototypical hydrogen-deficient binary (HdB), and one of only four such systems known. The unusual spectrum of hydrogen-deficient binaries has made stellar classification of Upsilon Sagittarii difficult.

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<span class="mw-page-title-main">OJ 287</span> BL Lac object in the constellation Cancer

OJ 287 is a BL Lac object 4 billion light-years from Earth that has produced quasi-periodic optical outbursts going back approximately 120 years, as first apparent on photographic plates from 1891. Seen on photographic plates since at least 1887, it was first detected at radio wavelengths during the course of the Ohio Sky Survey. It is a supermassive black hole binary (SMBHB). The intrinsic brightness of the flashes corresponds to over a trillion times the Sun's luminosity, greater than the entire Milky Way galaxy's light output.

KW Sagittarii is a red supergiant star, located approximately 2,420 parsecs away from the Sun in the direction of the constellation Sagittarius. It is one of the largest known stars, with a diameter about 1,000 times larger than the Sun. If placed at the center of the Solar System, the star's surface would engulf Mars, coming close to Jupiter's orbit.

LS I +61 303 is a binary system containing a massive star and a compact object. The compact object is a pulsar and the system is around 7,000 light-years away.

<span class="mw-page-title-main">GRS 1915+105</span> Binary system in the constellation Aquila

GRS 1915+105 or V1487 Aquilae is an X-ray binary star system containing a main sequence star and a black hole. Transfer of material from the star to the black hole generates a relativistic jet, making this a microquasar system. The jet exhibits apparent superluminal motion.

<span class="mw-page-title-main">V404 Cygni</span> Star and black hole binary star system in the constellation Cygnus

V404 Cygni is a microquasar and a binary system in the constellation of Cygnus. It contains a black hole with a mass of about 9 M☉ and an early K giant star companion with a mass slightly smaller than the Sun. The star and the black hole orbit each other every 6.47129 days at fairly close range. Due to their proximity and the intense gravity of the black hole, the companion star loses mass to an accretion disk around the black hole and ultimately to the black hole itself.

<span class="mw-page-title-main">9 Sagittarii</span> Star in the constellation Sagittarius

9 Sagittarii is a massive binary star in the constellation Sagittarius. It has an apparent magnitude of 5.97. Both components are highly luminous O-type main-sequence stars.

<span class="mw-page-title-main">X Persei</span> Variable star in the constellation Perseus

X Persei is a high-mass X-ray binary system located in the constellation Perseus, approximately 950 parsecs away. It is catalogued as 4U 0352+309 in the final Uhuru catalog of X-ray objects.

<span class="mw-page-title-main">HD 168607</span> Star in the constellation Sagittarius

HD 168607 is a blue hypergiant and luminous blue variable (LBV) star located in the constellation of Sagittarius, easy to see with amateur telescopes. It forms a pair with HD 168625, also a blue hypergiant and possible luminous blue variable, that can be seen at the south-east of M17, the Omega Nebula.

<span class="mw-page-title-main">V3903 Sagittarii</span> Binary star system in the constellation Sagittarius

V3903 Sagittarii is an eclipsing binary star system in the constellation Sagittiarus. It creates an H II region LBN 29 1,070 parsecs away from the Sun.

<span class="mw-page-title-main">V4743 Sagittarii</span> Nova that appeared in 2002

V4743 Sagittarii was a bright nova in the southern constellation of Sagittarius. This event was discovered by K. Haseda and colleagues in September 2002. It peaked at magnitude 5.0 on September 20, 2002, then declined rapidly thereafter. It reached a peak temperature of 740,000 K around April 2003 and remained at that level for at least five months, suggesting the white dwarf component has a mass of 1.1–1.2 M☉. The distance to this system is uncertain. Infrared observations indicate a distance of approximately 21 kly (6.3 kpc). A derivation using maximum magnitude rate of decay showed a distance of 12.7 ± 1.0 kly (3.9 ± 0.3 kpc).

<span class="mw-page-title-main">UZ Fornacis</span> Binary star system in the constellation Fornax

UZ Fornacis is a binary star in the constellation of Fornax. It appears exceedingly faint with a maximum apparent magnitude 17.0. Its distance, as measured by Gaia using the parallax method, is about 780 light-years.

<span class="mw-page-title-main">V4332 Sagittarii</span>

V4332 Sagittarii is a nova-like event in the constellation of Sagittarius. It was discovered February 24, 1994 at an apparent visual magnitude of 8.9 by Japanese amateur astronomer Minoru Yamamoto from Okazaki, Aichi, then confirmed by K. Hirosawa. Initially designated Nova Sagittarii 1994 #1, it was given the variable star designation V4332 Sgr. A spectra of the event taken March 4 lacked the characteristic features of a classical nova, with the only emission lines being of the Balmer series. Subsequent spectra showed a rapid decline in luminosity and a change of spectral type over a period of five days. By 2003, the object was ~1500 times less luminous than at peak magnitude and showed a spectrum of an M-type star.

<span class="mw-page-title-main">V356 Sagittarii</span> Star system in the constellation Sagittarius

V356 Sagittarii is an eclipsing binary star system in the southern constellation of Sagittarius, abbreviated V356 Sgr. It has a peak apparent visual magnitude of 6.84, which decreases to 7.66 during the primary eclipse and 7.24 with the secondary eclipse. Based on parallax measurements, this system is located at a distance of approximately 2,210 light years from the Sun.

References

  1. ↑ Goranskij, V. P. (May 2001). "The Orbital V-band Light Curve of V4641 Sagittarii". Information Bulletin on Variable Stars. 5068: 1. Bibcode:2001IBVS.5068....1G . Retrieved 13 March 2022.
  2. 1 2 3 4 5 6 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.
  3. 1 2 "V4641 Sgr". International Variable Star Index. Retrieved 2021-03-17.
  4. 1 2 3 4 5 MacDonald, Rachel K. D.; et al. (March 2014). "The Black Hole Binary V4641 Sagitarii: Activity in Quiescence and Improved Mass Determinations". The Astrophysical Journal. 784 (1): 19. arXiv: 1401.4190 . Bibcode:2014ApJ...784....2M. doi:10.1088/0004-637X/784/1/2. S2CID   119279780. 2.
  5. ↑ "V4641 Sgr". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2021-03-16.
  6. ↑ "Dramatic Outburst Reveals Nearest Black Hole". National Radio Astronomy Observatory . January 14, 2000. Retrieved 2008-08-30.
  7. 1 2 Orosz, J. A.; et al. (July 2001). "A Black Hole in the Superluminal Source SAX J1819.3-2525 (V4641 SGR)". The Astrophysical Journal. 555 (1): 489–503. arXiv: astro-ph/0103045 . Bibcode:2001ApJ...555..489O. doi:10.1086/321442. S2CID   50248739. Finally, we find a distance in the range 7.40 ≤ d ≤ 12.31 kpc (90% confidence), which is at least a factor of ≈ 15 larger than the initially assumed distance of ≈ 1,600 light-years/500 pc.
  8. ↑ Alfaro, R.; Alvarez, C.; Arteaga-Velázquez, J. C.; Avila Rojas, D.; Ayala Solares, H. A.; Babu, R.; Belmont-Moreno, E.; Caballero-Mora, K. S.; Capistrán, T.; Carramiñana, A.; Casanova, S.; Cotti, U.; Cotzomi, J.; Coutiño de León, S.; De la Fuente, E.; Depaoli, D.; Di Lalla, N.; Diaz Hernandez, R.; Dingus, B. L.; DuVernois, M. A.; Durocher, M.; Díaz-Vélez, J. C.; Engel, K.; Espinoza, C.; Fan, K. L.; Fang, K.; Fraija, N.; Fraija, S.; García-González, J. A.; Garfias, F.; Gonzalez Muñoz, A.; González, M. M.; Goodman, J. A.; Groetsch, S.; Harding, J. P.; Herzog, I.; Hinton, J.; Huang, D.; Hueyotl-Zahuantitla, F.; Hüntemeyer, P.; Iriarte, A.; Joshi, V.; Kaufmann, S.; Kieda, D.; de León, C.; Lee, J.; León Vargas, H.; Linnemann, J. T.; Longinotti, A. L.; Luis-Raya, G.; Malone, K.; Martinez, O.; Martínez-Castro, J.; Matthews, J. A.; Miranda-Romagnoli, P.; Morales-Soto, J. A.; Moreno, E.; Mostafá, M.; Nayerhoda, A.; Nellen, L.; Newbold, M.; Nisa, M. U.; Noriega-Papaqui, R.; Olivera-Nieto, L.; Omodei, N.; Osorio, M.; Pérez Araujo, Y.; Pérez-Pérez, E. G.; Rho, C. D.; Rosa-González, D.; Ruiz-Velasco, E.; Salazar, H.; Salazar-Gallegos, D.; Sandoval, A.; Schneider, M.; Serna-Franco, J.; Smith, A. J.; Son, Y.; Springer, R. W.; Tibolla, O.; Tollefson, K.; Torres, I.; Torres-Escobedo, R.; Turner, R.; Ureña-Mena, F.; Varela, E.; Villaseñor, L.; Wang, X.; Watson, I. J.; Willox, E.; Yun-Cárcamo, S.; Zhou, H. (17 October 2024). "Ultra-high-energy gamma-ray bubble around microquasar V4641 Sgr". Nature. 634 (8034): 557–560. doi:10.1038/s41586-024-07995-9. PMID   39415065.
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