Astronomy:b Persei
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Perseus |
| Right ascension | 04h 18m 14.61690s[1] |
| Declination | +50° 17′ 43.8058″[1] |
| Apparent magnitude (V) | 4.52 - 4.68[2] |
| Characteristics | |
| Spectral type | A1III[3] |
| B−V color index | +0.04[4] |
| Variable type | Ellipsoidal[2] |
| Astrometry | |
| Radial velocity (Rv) | 19.8±0.9[5] km/s |
| Proper motion (μ) | RA: 45.42±0.40[1] mas/yr Dec.: −56.72±0.32[1] mas/yr |
| Parallax (π) | 10.40 ± 0.35[1] mas |
| Distance | 310 ± 10 ly (96 ± 3 pc) |
| Absolute magnitude (MV) | 0.3[6] |
| Orbit[7] | |
| Primary | A or Aa |
| Companion | B or Ab |
| Period (P) | 1.52735997±0.00000036 days |
| Eccentricity (e) | 0.0 |
| Inclination (i) | 22±3 or 55±3[6]° |
| Periastron epoch (T) | 2450001.0931±0.003 |
| Orbit[8] | |
| Primary | AB |
| Companion | C or Ac |
| Period (P) | 703.06±0.07 days |
| Semi-major axis (a) | 26.22±0.06 mas |
| Eccentricity (e) | 0.185±0.003 |
| Inclination (i) | 90.5±0.1° |
| Longitude of the node (Ω) | 120.0±0.1° |
| Periastron epoch (T) | 2440080±3 |
| Argument of periastron (ω) (secondary) | 212±1° |
| Details | |
| A or Aa | |
| Mass | 2.25[6] M☉ |
| Radius | 3.2[9] R☉ |
| Luminosity | 59[6] L☉ |
| Temperature | 9,000[6] K |
| Rotational velocity (v sin i) | 81[10] km/s |
| B or Ab | |
| Mass | 0.56[11] M☉ |
| Radius | 0.25[9] R☉ |
| Luminosity | 4.5 - 5.9[6] L☉ |
| Temperature | 6,700[6] K |
| C or Ac | |
| Mass | 1.24[11] M☉ |
| Luminosity | 2[12] L☉ |
| Other designations | |
BD+49°1150, GC 5174, HD 26961, HR 1324, HIP 20070, SAO 24531 | |
| Database references | |
| SIMBAD | data |
b Persei (also known as HD 26961) is a spectroscopic triple star in the constellation Perseus. Its apparent magnitude is 4.60, making it visible to the naked eye.[6] It is about 320 light years away.[1]
In addition to the primary, an A-type giant, there is a smaller and cooler companion in a 1.53 day orbit, probably an F-class star around absolute magnitude 3.0, and a more distant companion (star C or Ac) in an orbit calculated to be 702 days long.[6] The close binary pair forms a rotating ellipsoidal variable with a 1.53 day period. Star C forms an Algol-type variable system with the close binary, showing both primary eclipses (when star C passes in front of the inner pair) and secondary eclipses (when the inner pair passes in front of star C).[13] Timings of the eclipses show a 704.5-day period.[12]

References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V. Vizier catalog entry
- ↑ 2.0 2.1 Samus, N. N. 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. Bibcode: 2009yCat....102025S.
- ↑ Abt, Helmut A. (2009). "MK Classifications of Spectroscopic Binaries". The Astrophysical Journal Supplement 180 (1): 117–18. doi:10.1088/0067-0049/180/1/117. Bibcode: 2009ApJS..180..117A.
- ↑ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A. Vizier catalog entry
- ↑ Wilson, R. E. (1953). "General Catalogue of Stellar Radial Velocities". Carnegie Institute Washington D.C. Publication (Carnegie Institution for Science). Bibcode: 1953GCRV..C......0W.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 Hill, G.; Aikman, G. C. L.; Cowley, A. P.; Bolton, C. T.; Thomas, J. C. (1976). "The radio-flaring triple system B Per". The Astrophysical Journal 208: 152. doi:10.1086/154590. Bibcode: 1976ApJ...208..152H.
- ↑ Koubský, Pavel; Hadrava, Petr; Šarounová, Lenka (December 2004). "Study of b Per: an attempt to find lines of other components in the SB1 system". Spectroscopically and Spatially Resolving the Components of the Close Binary Stars. 318. Astronomical Society of the Pacific. pp. 103–106. Bibcode: 2004ASPC..318..103K.
- ↑ Collins, Donald F.; Sanborn, Jason; Zavala, Robert T. (May 2014). "Modern V Photometry of the Eclipsing Triple System b Persei". The Society for Astronomical Sciences 33rd Annual Symposium on Telescope Science. Society for Astronomical Sciences. pp. 205–211. Bibcode: 2014SASS...33..205C.
- ↑ 9.0 9.1 Duerbeck, H. W.; Schettler, A. (1979). "Photometric and spectroscopic study of the ellipsoidal variable b Persei". Acta Astronomica 29: 225. Bibcode: 1979AcA....29..225D.
- ↑ Royer, F. (2007). "Rotational velocities of A-type stars. III. Velocity distributions". Astronomy and Astrophysics 463 (2): 671–682. doi:10.1051/0004-6361:20065224. Bibcode: 2007A&A...463..671R.
- ↑ 11.0 11.1 Tokovinin, Andrei (23 February 2018). "The Updated Multiple Star Catalog". The Astrophysical Journal Supplement Series 235 (1): 6. doi:10.3847/1538-4365/aaa1a5. Bibcode: 2018ApJS..235....6T.
- ↑ 12.0 12.1 "Alert Notice 791: Anticipated secondary eclipse of b Per centered on September 29 2022 UT". https://mintaka.aavso.org/aavso-alert-notice-791.
- ↑ "b Per". AAVSO. https://www.aavso.org/vsx/index.php?view=detail.top&oid=26212.
- ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html.
- ↑ "Download Data". AAVSO. https://www.aavso.org/data-download.
