49 Camelopardalis

49 Camelopardalis is a variable star in the northern circumpolar constellation of Camelopardalis,^[9] located 313 light years from the Sun based on parallax measurements.^[2] It has the variable star designation BC Camelopardalis; 49 Camelopardalis is the Flamsteed designation. This star is a challenge to view with the naked eye, having a baseline apparent visual magnitude of 6.50.^[3] It is moving away from the Earth with a heliocentric radial velocity of +6.5 km/s.^[3]

49 Camelopardalis

A visual band light curve for 49 Camelopardalis, adapted from Adelman and Kaewkornmaung, (2005)[1]>
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Camelopardalis
Right ascension	07h 46m 27.41459s[2]
Declination	+62° 49′ 49.8895″[2]
Apparent magnitude (V)	6.50[3] (6.43–6.48)[4]
Characteristics
Spectral type	A7VpSrCrEuSiKsn[5]
B−V color index	0.262±0.002[3]
Variable type	α2 CVn[4]
Astrometry
Radial velocity (Rv)	6.5±0.5[3] km/s
Proper motion (μ)	RA: −36.63[6] mas/yr Dec.: −61.36[6] mas/yr
Parallax (π)	10.4369 ± 0.0566 mas[2]
Distance	313 ± 2 ly (95.8 ± 0.5 pc)
Absolute magnitude (MV)	1.58[3]
Details[7]
Mass	1.92+0.14 −0.25 M☉
Radius	2.32±0.33 R☉
Luminosity	17.4+3.5 −2.9 L☉
Surface gravity (log g)	3.99±0.13 cgs
Temperature	7,740±460 K
Metallicity [Fe/H]	−3.40±0.16 dex
Rotation	4.28677±0.00003 d[8]
Rotational velocity (v sin i)	25.8±1.0 km/s
Age	891+489 −316 Myr
Other designations
49 Cam, BC Cam, BD+63°733, GC 10422, HD 62140, HIP 37934, HR 2977, SAO 14322[9]
Database references
SIMBAD	data

This is a magnetic chemically peculiar star^[7] with a stellar classification of A7VpSrCrEuSiKsn,^[5] indicating it is an A-type main-sequence star with overabundances of various elements including strontium and europium, as well as broad, "nebulous" lines. The magnetic field of 49 Camelopardalis shows a relatively complex structure, in combination with distinct abundance patterns across the surface.^[10] It is classified as an Alpha² Canum Venaticorum type variable and its brightness varies from visual magnitude +6.43 down to +6.48 with a rotationally-modulated period of 4.29 days.^[4]

49 Camelopardalis has 1.9 times the mass of the Sun and 2.3 times the Sun's radius. It is around 891 million years old^[7] and is spinning with a period of 4.29 days.^[8] The star is radiating 17 times the luminosity of the Sun from its photosphere at an effective temperature of 7,740 K.^[7]

References

1. Adelman & Kaewkornmaung 2005.
2. 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.
3. Anderson & Francis 2012.
4. Samus et al. 2017.
5. Abt & Morrell 1995.
6. van Leeuwen 2007.
7. Sikora et al. 2019a.
8. Sikora et al. 2019b.
9. "49 Cam". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-22.
10. Silvester et al. 2017.

Sources

• Abt, Helmut A.; Morrell, Nidia I. (1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". Astrophysical Journal Supplement Series. 99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182.
• Adelman, S. J.; Kaewkornmaung, P. (June 2005). "uubyFCAPT photometry of the mCP stars HD 32633, θ Aur, 49 Cam, and 3 Hya". Astronomy & Astrophysics. 435 (3): 1099–1104. Bibcode:2005A&A...435.1099A. doi:10.1051/0004-6361:20042628.
• Anderson, E.; Francis, Ch. (25 May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
• van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
• Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869
• Sikora, J.; et al. (February 2019a). "A Volume-Limited Survey of mCP Stars Within 100pc I: Fundamental Parameters and Chemical Abundances". Monthly Notices of the Royal Astronomical Society. 483 (2): 2300–2324. arXiv:1811.05633. Bibcode:2019MNRAS.483.2300S. doi:10.1093/mnras/sty3105. S2CID 119089236.
• Sikora, J.; et al. (March 2019b), "A volume-limited survey of mCP stars within 100 pc II: rotational and magnetic properties", Monthly Notices of the Royal Astronomical Society, 483 (3): 3127–3145, arXiv:1811.05635, Bibcode:2019MNRAS.483.3127S, doi:10.1093/mnras/sty2895, S2CID 119415579
• Silvester, J.; et al. (October 2017). "The complex magnetic field topology of the cool Ap star 49 Cam". Monthly Notices of the Royal Astronomical Society. 471 (1): 962–975. arXiv:1706.09196. Bibcode:2017MNRAS.471..962S. doi:10.1093/mnras/stx1606. S2CID 54694617.