HD 113703

This article is about f Centauri. Not to be confused with F Centauri.

f Centauri

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Centaurus
Right ascension	13^h 06^m 16.70^s[1]
Declination	−48° 27′ 47.8″[1]
Apparent magnitude (V)	+4.71[2]
Characteristics
Evolutionary stage	Main sequence
Spectral type	B4V[3] + K0Ve[4]
U−B color index	−0.562[2]
B−V color index	−0.148±0.006[2]
Astrometry
Radial velocity (Rv)	+6.0±4.2[5] km/s
Proper motion (μ)	RA: −29.558[1] mas/yr Dec.: −15.692[1] mas/yr
Parallax (π)	8.1592 ± 0.1559 mas[1]
Distance	400 ± 8 ly (123 ± 2 pc)
Absolute magnitude (MV)	−0.68[2]
Details
f Cen Aa
Mass	4.39[6] M☉
Surface gravity (log g)	3.99[6] cgs
Temperature	14,769[6] K
Rotational velocity (v sin i)	140±7[7] km/s
Age	92[6] Myr
f Cen C
Mass	0.9[8] M☉
Luminosity	0.49[8] L☉
Temperature	5,020[8] K
Age	50[8] Myr
Other designations
f Cen, CD−47°8088, GC 17750, HD 113703, HIP 63945, HR 4940, SAO 223900, CCDM J13063-4828
Database references
SIMBAD	data

HD 113703, also known by the Bayer designation f Centauri, is a multiple star[9] system in the southern constellation of Centaurus. The combined apparent visual magnitude of this system is +4.71,[2] which is sufficient to make it faintly visible to the naked eye. The distance to this system is approximately 400 light years based on parallax measurements. It is a member of the Lower Centaurus Crux subgroup of the Scorpius–Centaurus association.[6]

The primary of f Centauri is a blue-white hued B-type main-sequence star with a stellar classification of B4V.[3] It is a young star with an age estimated at around 92 million years,[6] and is spinning rapidly with a projected rotational velocity of 140 km/s.[7] A close companion with a K magnitude of 9.16, designated component C, was detected in 2002 at an angular separation of 1.55″.[10] In 2013, a spectroscopic companion to the primary was observed using long baseline interferometry, with the two being designated components Aa and Ab.[11]

A faint, magnitude 10.8 companion, component B, was first reported by J. F. W. Herschel in 1836. As of 2015, it was located at a separation of 11.6″ along a position angle of 78°.[12] This is a K-type star with a class of K0Ve, showing emission in the Calcium H and K lines. It is a known BY Draconis variable star with the designation V1155 Centauri.[13] It shares a common space motion with the primary, indicating a probable physical relationship, and its Gaia Data Release 3 parallax of 7.965″±0.018″ suggests a distance of 409 light years.[14] The star shows a strong overabundance in lithium, which demonstrates its young age.[4] It is about 0.8 magnitudes above zero age main sequence and thus is still contracting as a post-T Tauri star.[15] X-ray emission has been detected from this star.[8]

References

1. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
2. 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.
3. Houk, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 2. Ann Arbor: Dept. of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H.
4. Catchpole, R. M. (1971). "A lithium rich star in Sco-Cen". Monthly Notices of the Royal Astronomical Society. 154: 15. Bibcode:1971MNRAS.154P..15C. doi:10.1093/mnras/154.1.15P.
5. Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
6. Goldman, Bertrand; et al. (November 2018). "A Large Moving Group within the Lower Centaurus Crux Association". The Astrophysical Journal. 868 (1): 15. arXiv:1807.02076. Bibcode:2018ApJ...868...32G. doi:10.3847/1538-4357/aae64c. S2CID 119343278. 32.
7. Brown, A. G. A.; Verschueren, W. (March 1997). "High S/N Echelle spectroscopy in young stellar groups. II. Rotational velocities of early-type stars in SCO OB2". Astronomy and Astrophysics. 319: 811–838. arXiv:astro-ph/9608089. Bibcode:1997A&A...319..811B.
8. Stelzer, B.; et al. (September 2003). "Late B-type stars and their candidate companions resolved with Chandra". Astronomy and Astrophysics. 407 (3): 1067–1078. arXiv:astro-ph/0306401. Bibcode:2003A&A...407.1067S. doi:10.1051/0004-6361:20030934. S2CID 16766165.
9. Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID 14878976.
10. Shatsky, N.; Tokovinin, A. (January 2002). "The mass ratio distribution of B-type visual binaries in the Sco OB2 association". Astronomy and Astrophysics. 382: 92–103. arXiv:astro-ph/0109456. Bibcode:2002A&A...382...92S. doi:10.1051/0004-6361:20011542. S2CID 16697655.
11. Rizzuto, A. C.; et al. (December 2013). "Long-baseline interferometric multiplicity survey of the Sco-Cen OB association". Monthly Notices of the Royal Astronomical Society. 436 (2): 1694–1707. arXiv:1309.3811. Bibcode:2013MNRAS.436.1694R. doi:10.1093/mnras/stt1690.
12. Mason, B. D.; et al. (2014). "The Washington Visual Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.
13. 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: B/gcvs. Bibcode:2009yCat....102025S.
14. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
15. Andrews, P. J.; Thackeray, A. D. (1973). "Absolute magnitudes of B-type primaries in visual binaries". Monthly Notices of the Royal Astronomical Society. 165: 1–9. Bibcode:1973MNRAS.165....1A. doi:10.1093/mnras/165.1.1.