Wikipedia

Lambda Librae

λ Librae (Latinised as Lambda Librae) is the Bayer designation for a binary star system in the zodiac constellation of Libra. It can be faintly seen with the naked eye, having an apparent visual magnitude of 5.03.[3] With an annual parallax shift of 10.54 mas,[2] it is roughly 310 light years from the Sun. At that distance, the visual magnitude of this system is diminished by an extinction factor of 0.22 due to interstellar dust.[7] It is 0.1 degree north of the ecliptic.

Lambda Librae

A light curve for Lambda Librae, adapted from Wraight et al. (2012)[1]
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Libra
Right ascension 15h 53m 20.05463s[2]
Declination −20° 10′ 01.4177″[2]
Apparent magnitude (V) 5.03[3]
Characteristics
Spectral type B3 V[4]
U−B color index −0.584[3]
B−V color index −0.023[3]
Variable type Rotating ellipsoidal[5]
Astrometry
Radial velocity (Rv)−2.0±0.5[6] km/s
Proper motion (μ) RA: −9.81[2] mas/yr
Dec.: −26.85[2] mas/yr
Parallax (π)10.54 ± 0.91 mas[2]
Distance310 ± 30 ly
(95 ± 8 pc)
Absolute magnitude (MV)0.56[7]
Orbit[8]
Period (P)14.4829±0.0004 d
Eccentricity (e)0.27±0.09
Periastron epoch (T)2435172.380 ± 0.664 JD
Argument of periastron (ω)
(secondary)		217±17°
Semi-amplitude (K1)
(primary)		28.5±3.3 km/s
Details
Mass5.01±0.26[9] M☉
Radius3.9[10] R☉
Luminosity743[9] L☉
Surface gravity (log g)4.75 cgs
Temperature18,700[9] K
Metallicity [Fe/H]−0.27 dex
Rotational velocity (v sin i)155[11] km/s
Age282[7] Myr
Other designations
λ Lib, 45 Lib, BD−19°4249, FK5 1415, HD 142096, HIP 77811, HR 5902, SAO 183895.[12]
Database references
SIMBADdata

This is a single-lined spectroscopic binary star system with an orbital period of 14.48 days and an eccentricity of 0.27.[8] The visible component is a B-type main sequence star with a stellar classification of B3 V.[4] It is a helium-weak chemically peculiar star[13] and a rotating ellipsoidal variable.[5] The star has an estimated 3.9[10] times the radius of the Sun and five times the Sun's mass.[9] This is a candidate Vega-like star, meaning that it shows an infrared excess characteristic of a circumstellar debris disk.[14] The system is a source of X-ray emission.[15]

References

edit
  1. ^ Wraight, K. T.; Fossati, L.; Netopil, M.; Paunzen, E.; Rode-Paunzen, M.; Bewsher, D.; Norton, A. J.; White, Glenn J. (February 2012). "A photometric study of chemically peculiar stars with the STEREO satellites – I. Magnetic chemically peculiar stars". Monthly Notices of the Royal Astronomical Society. 420 (1): 757–772. arXiv:1110.6283. Bibcode:2012MNRAS.420..757W. doi:10.1111/j.1365-2966.2011.20090.x.757-772&rft.date=2012-02&rft_id=info:arxiv/1110.6283&rft_id=info:doi/10.1111/j.1365-2966.2011.20090.x&rft_id=info:bibcode/2012MNRAS.420..757W&rft.aulast=Wraight&rft.aufirst=K. T.&rft.au=Fossati, L.&rft.au=Netopil, M.&rft.au=Paunzen, E.&rft.au=Rode-Paunzen, M.&rft.au=Bewsher, D.&rft.au=Norton, A. J.&rft.au=White, Glenn J.&rft_id=https://doi.org/10.1111%2Fj.1365-2966.2011.20090.x&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  2. ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.653-664&rft.date=2007&rft_id=info:arxiv/0708.1752&rft_id=https://api.semanticscholar.org/CorpusID:18759600#id-name=S2CID&rft_id=info:doi/10.1051/0004-6361:20078357&rft_id=info:bibcode/2007A&A...474..653V&rft.aulast=van Leeuwen&rft.aufirst=F.&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  3. ^ a b c d Gutierrez-Moreno, Adelina; Moreno, Hugo (June 1968), "A photometric investigation of the Scorpio-Centaurus association", Astrophysical Journal Supplement, 15: 459, Bibcode:1968ApJS...15..459G, doi:10.1086/190168.
  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 Hoffleit, Dorrit (1996), "A Catalogue of Correlations Between Eclipsing Binaries and Other Categories of Double Stars", The Journal of the American Association of Variable Star Observers, 24 (2): 105–116, Bibcode:1996JAVSO..24..105H.105-116&rft.date=1996&rft_id=info:bibcode/1996JAVSO..24..105H&rft.aulast=Hoffleit&rft.aufirst=Dorrit&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  6. ^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 86351347, A61.
  7. ^ a b c Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035, S2CID 119108982.694-706&rft.date=2012-11&rft_id=info:arxiv/1606.09028&rft_id=https://api.semanticscholar.org/CorpusID:119108982#id-name=S2CID&rft_id=info:doi/10.1134/S1063773712110035&rft_id=info:bibcode/2012AstL...38..694G&rft.aulast=Gontcharov&rft.aufirst=G. A.&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  8. ^ a b Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; et al. (2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy & Astrophysics, 424 (2): 727–732, arXiv:astro-ph/0406573, Bibcode:2004A&A...424..727P, doi:10.1051/0004-6361:20041213, S2CID 119387088.727-732&rft.date=2004&rft_id=info:arxiv/astro-ph/0406573&rft_id=https://api.semanticscholar.org/CorpusID:119387088#id-name=S2CID&rft_id=info:doi/10.1051/0004-6361:20041213&rft_id=info:bibcode/2004A&A...424..727P&rft.aulast=Pourbaix&rft.aufirst=D.&rft.au=Tokovinin, A. A.&rft.au=Batten, A. H.&rft.au=Fekel, F. C.&rft.au=Hartkopf, W. I.&rft.au=Levato, H.&rft.au=Morrell, N. I.&rft.au=Torres, G.&rft.au=Udry, S.&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  9. ^ a b c d Hohle, M. M.; Neuhäuser, R.; Schutz, B. F. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten, 331 (4): 349, arXiv:1003.2335, Bibcode:2010AN....331..349H, doi:10.1002/asna.200911355, S2CID 111387483.
  10. ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) – Third edition – Comments and statistics", Astronomy and Astrophysics, 367 (2): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.521-524&rft.date=2001-02&rft_id=info:arxiv/astro-ph/0012289&rft_id=https://api.semanticscholar.org/CorpusID:425754#id-name=S2CID&rft_id=info:doi/10.1051/0004-6361:20000451&rft_id=info:bibcode/2001A&A...367..521P&rft.aulast=Pasinetti Fracassini&rft.aufirst=L. E.&rft.au=Pastori, L.&rft.au=Covino, S.&rft.au=Pozzi, A.&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  11. ^ Abt, Helmut A.; et al. (2002), "Rotational Velocities of B Stars", The Astrophysical Journal, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590.359-365&rft.date=2002&rft_id=info:doi/10.1086/340590&rft_id=info:bibcode/2002ApJ...573..359A&rft.aulast=Abt&rft.aufirst=Helmut A.&rft.au=Levato, Hugo&rft.au=Grosso, Monica&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  12. ^ "lam Lib -- Spectroscopic binary", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2017-01-30.
  13. ^ Renson, P.; Manfroid, J. (May 2009), "Catalogue of Ap, HgMn and Am stars", Astronomy and Astrophysics, 498 (3): 961–966, Bibcode:2009A&A...498..961R, doi:10.1051/0004-6361/200810788.961-966&rft.date=2009-05&rft_id=info:doi/10.1051/0004-6361/200810788&rft_id=info:bibcode/2009A&A...498..961R&rft.aulast=Renson&rft.aufirst=P.&rft.au=Manfroid, J.&rft_id=https://zenodo.org/record/890529&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  14. ^ Saffe, C.; Gómez, M.; Pintado, O.; González, E. (October 2008), "Spectroscopic metallicities of Vega-like stars", Astronomy and Astrophysics, 490 (1): 297–305, arXiv:0805.3936, Bibcode:2008A&A...490..297S, doi:10.1051/0004-6361:200810260, S2CID 15059920.297-305&rft.date=2008-10&rft_id=info:arxiv/0805.3936&rft_id=https://api.semanticscholar.org/CorpusID:15059920#id-name=S2CID&rft_id=info:doi/10.1051/0004-6361:200810260&rft_id=info:bibcode/2008A&A...490..297S&rft.aulast=Saffe&rft.aufirst=C.&rft.au=Gómez, M.&rft.au=Pintado, O.&rft.au=González, E.&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
  15. ^ Berghoefer, T. W.; Schmitt, J. H. M. M.; Cassinelli, J. P. (September 1996), "The ROSAT all-sky survey catalogue of optically bright OB-type stars", Astronomy and Astrophysics Supplement, 118 (3): 481–494, Bibcode:1996A&AS..118..481B, doi:10.1051/aas:1996213.481-494&rft.date=1996-09&rft_id=info:doi/10.1051/aas:1996213&rft_id=info:bibcode/1996A&AS..118..481B&rft.aulast=Berghoefer&rft.aufirst=T. W.&rft.au=Schmitt, J. H. M. M.&rft.au=Cassinelli, J. P.&rfr_id=info:sid/en.wikipedia.org:Lambda Librae" class="Z3988">
Retrieved from "https://en.wikipedia.org/w/index.php?title=Lambda_Librae&oldid=1246641088"