3 Puppis

This article is about l Puppis and is not to be confused with j Puppis or L Puppis.

3 Puppis

Location of 3 Puppis (circled)
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]
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
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
Other designations
l  Puppis, GSC  06552-03228, HD  62623, HIP  37677, HR  2996, SAO  174400, CD−28°4774
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 transferring 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

1. Calculated from rotational velocity divided by critical velocity, 35/178 = 0.20.

References

1. 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.
2. 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.
3. 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.
4. 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.
5. 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.
6. 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. arXiv: 2005.07754 . Bibcode:2020ApJ...897...48M. doi: 10.3847/1538-4357/ab93d9 . ISSN   0004-637X.