  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Lupus |
| Right ascension | 15h 50m 57.5376s[1] |
| Declination | −33° 37′ 37.796″[1] |
| Apparent magnitude (V) | 3.982±0.018[2] |
| Characteristics | |
| Spectral type | B9.5V + A2Vm[3] + K3V[4] |
| U−B color index | −0.13[5] |
| B−V color index | −0.04[5] |
| R−I color index | −0.07[5] |
| Astrometry | |
| Proper motion (μ) | RA: −5.10 mas/yr[6] Dec.: −24.85 mas/yr[6] |
| Parallax (π) | 16.71±0.27 mas[6] |
| Distance | 203.1±5.5 ly (62.27±1.70 pc)[7] |
| Orbit[7] | |
| Primary | χ Lup A |
| Companion | χ Lup B |
| Period (P) | 15.256560(71) days |
| Semi-major axis (a) | 0.2030±0.0029 au |
| Eccentricity (e) | 0.0076±0.0054 |
| Inclination (i) | 110.2±2.1° |
| Longitude of the node (Ω) | −127.1±1.5° |
| Periastron epoch (T) | 2,438,434.4±1.7 JD |
| Argument of periastron (ω) (secondary) | 116±40° |
| Orbit[4] | |
| Primary | χ Lup Ab |
| Companion | χ Lup C |
| Period (P) | 9 years |
| Semi-major axis (a) | 7.5 au |
| Details[7] | |
| χ Lup A | |
| Mass | 2.84±0.12 M☉ |
| Radius | 2.85±0.15 R☉ |
| Luminosity | 63[8] L☉ |
| Surface gravity (log g) | 4.08[8] cgs |
| Temperature | 10,200[8] K |
| Rotational velocity (v sin i) | 0[5] km/s |
| Age | 280±30 Myr |
| χ Lup B | |
| Mass | 1.94±0.09 M☉ |
| Radius | 1.75±0.18 R☉ |
| Surface gravity (log g) | 4.2 cgs |
| Temperature | 9,200 K |
| χ Lup C | |
| Mass | 0.79[4] M☉ |
| Other designations | |
| χ Lup, Chi Lupi, Chi Lup, 5 Lupi, 5 Lup, CD−33 10754, CPD−33 3933, FK5 586, GC 21281, HD 141556, HIP 77634, HR 5883, PPM 294334, SAO 207040[1] | |
| Database references | |
| SIMBAD | data |
Chi Lupi (Chi Lup, χ Lupi, χ Lup) is a triple star system in the constellation of Lupus. It has an apparent visual magnitude of approximately 3.957.
The primary star in the binary is a mercury-manganese star of spectral type B9.5V; the secondary is a metallic-lined star of type A2Vm.[3] The tertiary is a red dwarf.[4]
This system is a proper motion member of the Upper Scorpius sub-group in the Scorpius–Centaurus OB association, the nearest such co-moving association of massive stars to the Sun.[8] The Upper Scorpius subgroup contains thousands of stars with an average age of 11 million years old at mean distances of 145 parsecs (470 light years).[9]
References
[edit]- ^ a b c "chi Lup". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved August 14, 2008.
- ^ Paunzen, E. (2015-08-01). "A new catalogue of Strömgren-Crawford uvbyβ photometry". Astronomy and Astrophysics. 580: A23. arXiv:1506.04568. Bibcode:2015A&A...580A..23P. doi:10.1051/0004-6361/201526413. ISSN 0004-6361.
- ^ a b On the Ga II and Ga III Resonance Lines and the Implication for Chemical Stratification in HgMn Stars, K. E. Nielsen et al., Astronomical Journal 130, #5 (November 2005), pp. 2312–2317, Bibcode:2005AJ....130.2312N, doi:10.1086/491703.
- ^ a b c d Waisberg, Idel; Klein, Ygal; Katz, Boaz (2025-08-21). "Hidden Companions to Intermediate-mass Stars. Upgraded Multiplicity 2 → 3. XXX. Discovery of a 0.79 M☉, 7.5 au Outer Companion to the 0.20 au HgMn Binary Chi Lupi*". Research Notes of the AAS. 9 (8): 225. doi:10.3847/2515-5172/adfccb. ISSN 2515-5172.
- ^ a b c d HR 5883, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line August 14, 2008.
- ^ a b van Leeuwen, F. (November 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.
- ^ a b c Le Bouquin, J.-B.; Beust, H.; Duvert, G.; Berger, J. P.; Ménard, F.; Zins, G. (March 2013). "Masses and age of the chemically peculiar double-lined binary χ Lupi". Astronomy & Astrophysics. 551: 9. arXiv:1302.5014. Bibcode:2013A&A...551A.121L. doi:10.1051/0004-6361/201220454. S2CID 13860888. A121.
- ^ a b c d de Geus, E. J.; de Zeeuw, P. T.; Lub, J. (June 1989). "Physical parameters of stars in the Scorpio-Centaurus OB association". Astronomy and Astrophysics. 216 (1–2): 44–61. Bibcode:1989A&A...216...44D.
- ^ Mark J. Pecaut; Eric E. Mamajek & Eric J. Bubar (February 2012). "A Revised Age for Upper Scorpius and the Star Formation History among the F-type Members of the Scorpius–Centaurus OB Association". Astrophysical Journal. 746 (2): 154. arXiv:1112.1695. Bibcode:2012ApJ...746..154P. doi:10.1088/0004-637X/746/2/154. S2CID 118461108.
