V4199 Sagittarii is a variable star in the southern constellation of Sagittarius.[8] It is a dim star that is just visible to the naked eye with an apparent visual magnitude that varies between 6.22 and 6.28 over a period of 1.23825 days.[9] The star is located at a distance of approximately 689 light years from the Sun based on parallax, but is drifting closer with a radial velocity of roughly −23 km/s.[6] It has an absolute magnitude of −0.63,[3] on average.

V4199 Sagittarii

A light curve for V4199 Sagittarii, plotted from Hipparcos data[1]
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Sagittarius
Right ascension 19h 21m 37.11363s[2]
Declination −19° 14′ 04.0500″[2]
Apparent magnitude (V) 6.25[3]
Characteristics
Spectral type B5III[4]
B−V color index −0.091±0.004[3]
Variable type SPB[5]
Astrometry
Radial velocity (Rv)−23.3±7.4[6] km/s
Proper motion (μ) RA: +3.135 mas/yr
Dec.: −12.136 mas/yr
Parallax (π)4.7371 ± 0.0556 mas[2]
Distance689 ± 8 ly
(211 ± 2 pc)
Absolute magnitude (MV)−0.63[3]
Details[5]
Mass4.2±0.3 M
Radius2.9±0.5 R
Luminosity316+82
−66
 L
Surface gravity (log g)4.16±0.20 cgs
Temperature14,700±700 K
Rotational velocity (v sin i)6±4 km/s
Age48.9±21.6[7] Myr
Other designations
173 G. Sagittarii, BD−19°5412, HD 181558, HIP 95159, HR 7339, SAO 162511, WDS 19216-1914[8]
Database references
SIMBADdata

The stellar classification of this star is B5III,[4] matching a B-type giant star. In the Bright Star Catalogue it was listed as a main sequence star of class B5V, although the colors suggest a somewhat more evolved star.[10] The photometric variability of this star was announced by C. Waelkens and F. Rufener in 1984.[11] It is a multi-periodic[10] slowly pulsating B star with a dominant frequency of 0.80780±0.00010 cycles/day.[12] The star has four times the mass of the Sun and three times the Sun's radius. It is radiating ~316 times the luminosity of the Sun from its photosphere at an effective temperature of 14,700 K. A magnetic field has been detected on this star with a strength of −104±32 G.[5]

It has a magnitude 9.96 companion star at an angular separation of 90.9 along a position angle of 310°, as of 2003.[13]

References

edit
  1. ^ "Light Curve". Hipparcos ESA. ESA. Retrieved 17 February 2022.
  2. ^ a b c 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. ^ a b c d 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.
  4. ^ a b Houk, Nancy; Smith-Moore, M. (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 4. Ann Arbor: Dept. of Astronomy, University of Michigan. Bibcode:1988mcts.book.....H.
  5. ^ a b c Hubrig, S.; et al. (April 2009). "New magnetic field measurements of β Cephei stars and slowly pulsating B stars". Astronomische Nachrichten. 330 (4): 317. arXiv:0902.1314. Bibcode:2009AN....330..317H. doi:10.1002/asna.200811187. S2CID 17497112.
  6. ^ a b Kharchenko, N. V.; et al. (2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten. 328 (9): 889. arXiv:0705.0878. Bibcode:2007AN....328..889K. doi:10.1002/asna.200710776. S2CID 119323941.
  7. ^ Tetzlaff, N.; et al. (January 2011). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. S2CID 118629873.
  8. ^ a b "V* V4199 Sgr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 12 August 2013.
  9. ^ Otero, Sebastian (10 February 2012). "V4199 Sgr". The International Variable Star Index. Retrieved 14 July 2014.
  10. ^ a b Waelkens, C. (June 1991). "Slowly pulsating B stars". Astronomy and Astrophysics. 246: 453. Bibcode:1991A&A...246..453W.
  11. ^ Waelkens, C.; Rufener, F. (November 1985). "Photometric variability of mid-B stars". Astronomy and Astrophysics. 152: 6–14. Bibcode:1985A&A...152....6W.
  12. ^ De Cat, P.; et al. (March 2005). "A study of bright southern slowly pulsating B stars. III. Mode identification for singly-periodic targets in spectroscopy". Astronomy and Astrophysics. 432 (3): 1013–1024. Bibcode:2005A&A...432.1013D. doi:10.1051/0004-6361:20042103. hdl:2066/33307.
  13. ^ Mason, B. D.; et al. (2014). "The Washington Visual Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.