3 Puppis
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Puppis |
Right ascension | 07h 43m 48.46872s[1] |
Declination | −28° 57′ 17.3720″[1] |
Apparent magnitude (V) | 3.93[2] |
Characteristics | |
Spectral type | A2.7Ib[2] (A2Ia - A3IIpe[3]) |
Apparent magnitude (K) | 2.340[4] |
U−B color index | −0.09[5] |
B−V color index | +0.18[5] |
Astrometry | |
Radial velocity (Rv) | 26.4±2.0[6] km/s |
Proper motion (μ) | RA: −5.09 mas/yr[1] Dec.: +3.90 mas/yr[1] |
Parallax (π) | 0.59 ± 0.17 mas[1] |
Distance | 2,100±280 ly (630±85 pc)[6] |
Absolute magnitude (MV) | −5.5[2] |
Details[6] | |
A | |
Mass | 8.8±0.5 M☉ |
Radius | 54±7 R☉ |
Luminosity | 12,600+3,300 −2,600 L☉ |
Surface gravity (log g) | 1.9±0.1 cgs |
Temperature | 8,500±500 K |
Rotational velocity (v sin i) | 35±5 km/s |
B | |
Mass | 0.75±0.25 M☉ |
Radius | 0.3 R☉ |
Surface gravity (log g) | 5.0 cgs |
Temperature | 50,000 K |
Orbit[6] | |
Primary | A |
Companion | B |
Period (P) | 137.4±0.1 days |
Semi-major axis (a) | 1.11±0.03 AU |
Semi-amplitude (K1) (primary) | 5.0±0.8 km/s |
Other designations | |
Database references | |
SIMBAD | data |
3 Puppis (3 Pup) is a spectroscopic binary in the constellation Puppis. It is a very rare A[e] supergiant, referred to as a B[e] star despite its spectral classification, and its apparent magnitude is 3.93.
3 Puppis is surrounded by a disc of circumstellar dust, which is unusual for an A-type star.[3] It is caused by a low mass companion, a helium-rich subdwarf that is transfering mass to the supergiant. Due to mass transfer, its mass reduced from 3.6 M☉ when it formed to the current 0.75 M☉.[6] Like most B[e] stars, 3 Pup rotates rapidly, at 20%[a] of the speed at which it would start to break apart. The disc has its inner edge only 3.8 AU from the primary star and it is suspected that deceleration of the hot primary stellar wind by the companion allows the dust to form unusually close to such a luminous star.[3]
Notes
[edit]- ^ Calculated from rotational velocity divided by critial velocity, 35/178 = 0.20.
References
[edit]- ^ a b c d 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.
- ^ a b c Klochkova, V. G.; Sendzikas, E. G.; Chentsov, E. L. (2015). "Spectral atlas of A-type supergiants". Astrophysical Bulletin. 70 (1): 99–108. arXiv:1502.01444. Bibcode:2015AstBu..70...99K. doi:10.1134/S1990341315010113. S2CID 119229144.
- ^ a b c Meilland, A.; Kanaan, S.; Borges Fernandes, M.; Chesneau, O.; Millour, F.; Stee, Ph.; Lopez, B. (2010). "Resolving the dusty circumstellar environment of the A[e] supergiant HD 62623 with the VLTI/MIDI". Astronomy and Astrophysics. 512: A73. arXiv:0912.1954. Bibcode:2010A&A...512A..73M. doi:10.1051/0004-6361/200913640. S2CID 119225591.
- ^ Kraus, M.; Oksala, M. E.; Cidale, L. S.; Arias, M. L.; Torres, A. F.; Borges Fernandes, M. (2015). "Discovery of SiO Band Emission from Galactic B[e] Supergiants". The Astrophysical Journal Letters. 800 (2): L20. arXiv:1501.07063. Bibcode:2015ApJ...800L..20K. doi:10.1088/2041-8205/800/2/L20. S2CID 118847782.
- ^ a b Gutierrez-Moreno, A.; Moreno, H.; Loyola, P.; Cortes, G. (1986). "Low dispersion spectrophotometry of bright early-type stars". Astronomy and Astrophysics Supplement Series. 64: 205. Bibcode:1986A&AS...64..205G.
- ^ a b c d e Miroshnichenko, A. S.; Danford, S.; Zharikov, S. V.; Klochkova, V. G.; Chentsov, E. L.; Vanbeveren, D.; Zakhozhay, O. V.; Manset, N.; Pogodin, M. A.; Omarov, C. T.; Kuratova, A. K.; Khokhlov, S. A. (July 2020). "Properties of Galactic B[e] Supergiants. V. 3 Pup–Constraining the Orbital Parameters and Modeling the Circumstellar Environments". The Astrophysical Journal. 897 (1): 48. Bibcode:2020ApJ...897...48M. doi:10.3847/1538-4357/ab93d9. ISSN 0004-637X.