V356 Sagittarii

V356 Sagittarii

Light curves for V356 Sagittarii, in three photometric bands. Plotted from data published by Wilson and Woodward (1995).[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Sagittarius
Right ascension 18h 47m 52.331s[2]
Declination −20° 16′ 28.24″[2]
Apparent magnitude (V) 6.84
Min I: 7.66
Min II: 7.24[3]
Characteristics
Spectral type B3V + A2II[4]
B−V color index 0.120±0.029[5]
Variable type Detached Algol(?)[3]
Astrometry
Radial velocity (Rv)7.0±4.4[5] km/s
Proper motion (μ) RA: +0.525 mas/yr[2]
Dec.: −4.847 mas/yr[2]
Parallax (π)1.4783 ± 0.0289 mas[2]
Distance2,210 ± 40 ly
(680 ± 10 pc)
Orbit[6]
Period (P)8.896106 d
Eccentricity (e)0.01566±0.01360
Argument of periastron (ω)
(secondary)		288.71851±0.42683°
Semi-amplitude (K1)
(primary)		72.17896±1.25080 km/s
Semi-amplitude (K2)
(secondary)		190 km/s
Details
Primary
Mass11.0[7] M☉
Radius9.07[7] R☉
Surface gravity (log g)3.96±0.10[4] cgs
Temperature16,500±750[4] K
Rotational velocity (v sin i)350[4] km/s
Secondary
Mass3.0[7] M☉
Radius13.2[7] R☉
Surface gravity (log g)2.82±0.10[4] cgs
Temperature8,600±300[4] K
Rotational velocity (v sin i)90[4] km/s
Other designations
V356 Sgr, BD−20°5268, GC 25739, HD 173787, HIP 92235, SAO 187294, PPM 268914[8]
Database references
SIMBADdata

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.[3] Based on parallax measurements, this system is located at a distance of approximately 2,210 light years from the Sun.[2]

This is a double-lined spectroscopic binary system with an orbital period of 8.896 days.[6] It is a massive, interacting system with a circular orbit, where the secondary component has filled its Roche lobe and is transferring matter to its companion. The primary is a B-type main-sequence star with a stellar classification of B3V. It was originally the lower mass component,[9] but now has about 11 times the mass of the Sun.[7] The secondary is an evolved supergiant star[9] with a present-day class of A2II.[4] It has been stripped of much of its original mass,[9] leaving behind the exposed core of a star.[10] The transfer of matter is creating an accretion disk in orbit around the primary.[9]

At least some of the material stripped from the current secondary component has likely been lost from the system. A relatively small change in the orbital period has been observed, but the period is fairly stable over time, which may mean the mass transfer is intermittent.[9] Ultraviolet emission has been observed with the FUSE space observatory, indicating the presence of hot circumstellar matter. This emission shows little variation during a total eclipse, suggesting the material lies perpendicular to the accretion disk. This could represent a bipolar jet of matter from the primary.[11]

References

  1. ^ Wilson, R. E.; Woodward, E. J. (February 1995). "U, B, V Light Curves of V356 Sagittarii". Publications of the Astronomical Society of the Pacific. 107: 132–135. Bibcode:1995PASP..107..132W. doi:10.1086/133528. S2CID 121011912. Retrieved 31 March 2023.
  2. ^ a b c d e 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 c Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
  4. ^ a b c d e f g h Polidan, R. S. (June 1988), "A new study of the interacting binary star V356 Sgr", ESA, A Decade of UV Astronomy with the IUE Satellite, vol. 1, pp. 205–208, Bibcode:1988ESASP.281a.205P.
  5. ^ a b Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  6. ^ a b Cabezas, M.; et al. (February 2017), Miroshnichenko, Anatoly; et al. (eds.), "New Spectroscopic Analysis and Light Curve Model of the Eclipsing Binary V356 Sgr", The B[e] Phenomenon: Forty Years of Studies. Proceedings of a Conference held at Charles University, Prague, Czech Republic 27 June - 1 July 2016, ASP Conference Series, vol. 508, San Francisco: Astronomical Society of the Pacific, p. 364, Bibcode:2017ASPC..508..367C.
  7. ^ a b c d e van Rensbergen, W.; et al. (April 2011), "Mass loss out of close binaries. The formation of Algol-type systems, completed with case B RLOF", Astronomy & Astrophysics, 528, arXiv:1008.2620, Bibcode:2011A&A...528A..16V, doi:10.1051/0004-6361/201015596, S2CID 118417156, A16.
  8. ^ "V356 Sgr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-03-29.
  9. ^ a b c d e Lomax, Jamie R.; et al. (January 2017), "The complex circumstellar and circumbinary environment of V356 Sgr", Monthly Notices of the Royal Astronomical Society, 464 (2): 1936–1947, arXiv:1609.07489, Bibcode:2017MNRAS.464.1936L, doi:10.1093/mnras/stw2457.
  10. ^ Dominis, D.; et al. (April 2005), "In between β Lyrae and Algol: The Case Of V356 Sgr", Astrophysics and Space Science, 296 (1–4): 189–192, Bibcode:2005Ap&SS.296..189D, doi:10.1007/s10509-005-4443-x, S2CID 121917890.
  11. ^ Peters, G. J.; Polidan, R. S. (March 2004), "Eclipse mapping of the hot circumstellar plasma in Algol binaries", Astronomische Nachrichten, 325 (3): 225–228, Bibcode:2004AN....325..225P, doi:10.1002/asna.200310224.

Further reading