CN Andromedae

CN Andromedae (CN And) is an eclipsing binary star in the constellation Andromeda. Its maximum apparent visual magnitude is 9.62 and drops down to a minimum of 10.2 during the main eclipse. It's classified as a Beta Lyrae variable with a period roughly of 0.4628 days.[2]

CN Andromedae
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension  00h 20m 30.54209s[1]
Declination +40° 13′ 33.80342″[1]
Apparent magnitude (V) 9.62 – 10.21 variable [2]
Characteristics
Spectral type F5V[2]
Apparent magnitude (B) 10.24[3]
Apparent magnitude (V) 9.706[3]
Apparent magnitude (G) 9.6637[1]
Apparent magnitude (J) 8.670[4]
Apparent magnitude (H) 8.452[4]
Apparent magnitude (K) 8.427[4]
B−V color index 0.49725[3]
Variable type EB[2]
Astrometry
Radial velocity (Rv)−24.2±1.0[5] km/s
Proper motion (μ) RA: −8.549±0.054 [1] mas/yr
Dec.: −35.291±0.024[1] mas/yr
Parallax (π)4.9670 ± 0.0425[1] mas
Distance657 ± 6 ly
(201 ± 2 pc)
Orbit[5]
Period (P)0.4627952±0.000035 days
Semi-major axis (a)3.066±0.035
Inclination (i)68.51±0.17°
Periastron epoch (T)HJD 2445231.51710±0.00059
Details
Primary
Mass1.433±0.030[6] M☉
Radius1.48±0.03[6] R☉
Luminosity3.40[6] L☉
Surface gravity (log g)4.24[5] cgs
Temperature6,450[6] K
Secondary
Mass0.552±0.020[6] M☉
Radius0.95[6] R☉
Luminosity0.40[6] L☉
Surface gravity (log g)4.22[5] cgs
Temperature4,726[6] K
Other designations
2MASS J00203054+4013337, BD+39 59, TYC 2787-1815-1
Database references
SIMBADdata

System

The two stars in this system orbit very close to each other; their spectrum cannot be separated and as a whole they have a spectrum of an F5V star. They are in marginal contact,[6] and there is a mass flow from the primary star to the secondary at a rate of 1.4 × 10−7 M☉ yr−1.[5]

Variability

The light curve of CN Andromedae shows a primary eclipse, with its brightness dropping down to 10.21 magnitude, and a secondary one down to a magnitude of 9.9.[2] This phenomenon repeats with a cycle of approximately 11.1 hours, with period decreasing in time due to the mass transfer from one star to the another.[5]

References
  1. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. CN And, database entry, Combined General Catalog of Variable Stars (GCVS4.2, 2004 Ed.), N. N. Samus, O. V. Durlevich, et al., CDS ID II/250 Accessed on line 2018-10-17.
  3. Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000), "The Tycho-2 catalogue of the 2.5 million brightest stars", Astronomy & Astrophysics, 355: L27–L30, Bibcode:2000A&A...355L..27H.
  4. Cutri, R. M.; Skrutskie, M. F.; Van Dyk, S.; et al. (June 2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues (2246): II/246. Bibcode:2003yCat.2246....0C.
  5. Van Hamme, W.; Samec, R. G.; Gothard, N. W.; Wilson, R. E.; Faulkner, D. R.; Branly, R. M. (2001). "CN Andromedae: A Broken-Contact Binary?". The Astronomical Journal. 122 (6): 3436–3446. Bibcode:2001AJ....122.3436V. doi:10.1086/324110.
  6. Siwak, M.; Zola, S.; Koziel-Wierzbowska, D. (2010). "A Study of Contact Binaries with Large Temperature Differences between Components". Acta Astronomica. 60 (4): 305–336. Bibcode:2010AcA....60..305S.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.