LP Andromedae (often abbreviated to LP And) is a carbon star in the constellation Andromeda. It is also a Mira variable[7] whose mean apparent visual magnitude is 15.12 and has pulsations with an amplitude of 1.50 magnitudes[3] and a period of 614 days.[8]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 23h 34m 27.5216s[2] |
| Declination | +43° 33′ 01.2996″[2] |
| Apparent magnitude (V) | 15.12 variable[3] |
| Characteristics | |
| Spectral type | C8,3.5e[4] |
| Apparent magnitude (G) | 16.9041[2] |
| Apparent magnitude (J) | 9.623[5] |
| Apparent magnitude (H) | 6.355[5] |
| Apparent magnitude (K) | 2.71[6] |
| Variable type | Mira[7] |
| Astrometry | |
| Proper motion (μ) | RA: −21.313±0.532 [2] mas/yr Dec.: −22.058±0.453[2] mas/yr |
| Parallax (π) | 2.5002 ± 0.3626 mas[2] |
| Distance | approx. 1,300 ly (approx. 400 pc) |
| Absolute bolometric magnitude (Mbol) | −5.21±0.26[8] |
| Details[8] | |
| Mass | 0.8 M☉ |
| Radius | 340 – 420 R☉ |
| Luminosity | 2,900 – 16,200 L☉ |
| Temperature | 2,100 – 3,350 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
In 1974 LP Andromedae, known then as IRC+40540, was identified as a carbon star and also shown to be variable.[9] It had previously been suspected of variability during the 2 Micron All Sky Survey (2MASS). A detailed study of its spectrum showed an unusually cool star with a basic class of C8, and Swan band strength of 3.5. It also showed strong C13 isotopic bands.[4] The period was narrowed down to around 614 days, one of the longest periods known for a Mira variable.[10]
This star has a dusty envelope with an estimated mass of 3.2 M☉, fueled by the star itself which is losing mass at a rate 1.9×10−5 M☉/yr. Such a high mass loss rate should place LP Andromedae close to the end of its asymptotic giant branch evolution. The envelope extends to a distance of 3 parsec from the star, and is mainly made of silicon carbide and carbon particles.[8]
See also
editReferences
edit- ^ Jones, Terry Jay; Bryja, C. O.; Gehrz, Robert D.; Harrison, Thomas E.; Johnson, Joni J.; Klebe, Dimitri I.; Lawrence, Geoffrey F. (November 1990). "Photometry of Variable AFGL Sources". Astrophysical Journal Supplement. 74: 785. Bibcode:1990ApJS...74..785J. doi:10.1086/191518.
- ^ a b c d e f 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.
- ^ a b Database entry, The Catalina Surveys periodic variable star catalog. (Drake+, 2014), A. J. Drake et al., CDS ID J/ApJS/213/9 Accessed on line 2018-11-14.
- ^ a b Cohen, M. (1979). "Circumstellar envelopes and the evolution of carbon stars". Monthly Notices of the Royal Astronomical Society. 186 (4): 837–852. Bibcode:1979MNRAS.186..837C. doi:10.1093/mnras/186.4.837.
- ^ a b Cutri, Roc M.; Skrutskie, Michael F.; Van Dyk, Schuyler D.; Beichman, Charles A.; Carpenter, John M.; Chester, Thomas; Cambresy, Laurent; Evans, Tracey E.; Fowler, John W.; Gizis, John E.; Howard, Elizabeth V.; Huchra, John P.; Jarrett, Thomas H.; Kopan, Eugene L.; Kirkpatrick, J. Davy; Light, Robert M.; Marsh, Kenneth A.; McCallon, Howard L.; Schneider, Stephen E.; Stiening, Rae; Sykes, Matthew J.; Weinberg, Martin D.; Wheaton, William A.; Wheelock, Sherry L.; Zacarias, N. (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.
- ^ Menzies, J. W.; Feast, M. W.; Whitelock, P. A. (June 2006). "Carbon-rich Mira variables: radial velocities and distances". Monthly Notices of the Royal Astronomical Society. 369 (2): 783–790. arXiv:astro-ph/0603505. Bibcode:2006MNRAS.369..783M. CiteSeerX 10.1.1.255.9712. doi:10.1111/j.1365-2966.2006.10323.x. S2CID 18684991.
- ^ a b N. N. Samus; O. V. Durlevich; et al. "LP And database entry". Combined General Catalog of Variable Stars (2017 ed.). CDS. Retrieved 2018-11-14.
- ^ a b c d Men'shchikov, A. B.; Balega, Y. Y.; Berger, M.; Driebe, T.; Hofmann, K.-H.; Maximov, A. F.; Schertl, D.; Shenavrin, V. I.; Weigelt, G. (March 2006). "Near-infrared speckle interferometry and radiative transfer modelling of the carbon star LP Andromedae". Astronomy and Astrophysics. 448 (1): 271–281. Bibcode:2006A&A...448..271M. doi:10.1051/0004-6361:20052976.
- ^ Lockwood, G. W. (1974). "Near-infrared photometry of unidentified IRC stars. II". The Astrophysical Journal. 192: 113. Bibcode:1974ApJ...192..113L. doi:10.1086/153041.
- ^ Alksnis, A. (1989). "On the Variability of the Dusty Carbon Star LP and". Information Bulletin on Variable Stars. 3396: 1. Bibcode:1989IBVS.3396....1A.