LS IV-14 116
Observation data EpochJ2000.0EquinoxJ2000.0 | |
---|---|
Constellation | Aquarius |
Right ascension | +20h57m38.875s[2] |
Declination | −14° 25′ 44.01″[2] |
Apparent magnitude(V) | +12.93[3] |
Characteristics | |
Spectral type | sdB0.5VIIHe18[4] |
B−Vcolor index | −0.16[3] |
Variable type | sdBVr[5][6] |
Details | |
Surface gravity(logg) | 5.94 ± 0.04[7]cgs |
Temperature | 34,950 ± 250[7]K |
Other designations | |
Database references | |
SIMBAD | data |
LS IV-14 116is a hotsubdwarflocated approximately 2,000light yearsaway on the border between the constellationsCapricornusandAquarius.It has a surface temperature of approximately 34,000 ± 500kelvins.[8]Along with starsHE 2359-2844andHE 1256-2738,LSIV-14 116 forms a new group of star calledheavy metal subdwarfs.These are thought to be stars contracting to the extendedhorizontal branchafter ahelium flashand ejection of their atmospheres at thetip of the red giant branch.[9]
The star contains 10,000 times morezirconiumthan theSun;it also has between 1,000 and 10,000 times the amount ofstrontium,germaniumandyttriumthan the Sun. The heavy metals are believed to be in cloud layers in the atmosphere where the ions of each metal have a particular opacity that allows radiational levitation to balance gravitational settling.[8]
References
[edit]- ^Nassau, J. J.; Stephenson, C. B. (1963). "Luminous Stars in the Northern Milky Way".Hamburger Sternw.04.Bibcode:1963LS....C04....0N.
- ^abZacharias, N.; Urban, S. E.; Zacharias, M. I.; Wycoff, G. L.; Hall, D. M.; Germain, M. E.; Holdenried, E. R.; Winter, L. (2003). "VizieR On-line Data Catalog: The Second U.S. Naval Observatory CCD Astrograph Catalog (UCAC2)".CDS/ADC Collection of Electronic Catalogues.1289.Bibcode:2003yCat.1289....0Z.
- ^abZacharias, N.; Finch, C. T.; Girard, T. M.; Henden, A.;Bartlett, J. L.;Monet, D. G.; Zacharias, M. I. (2012). "VizieR Online Data Catalog: UCAC4 Catalogue (Zacharias+, 2012)".VizieR On-line Data Catalog: I/322A. Originally Published in: 2012yCat.1322....0Z; 2013AJ....145...44Z.1322.Bibcode:2012yCat.1322....0Z.
- ^Drilling, J. S.; Jeffery, C. S.; Heber, U.; Moehler, S.; Napiwotzki, R. (2013)."An MK-like system of spectral classification for hot subdwarfs".Astronomy & Astrophysics.551:A31.Bibcode:2013A&A...551A..31D.doi:10.1051/0004-6361/201219433.
- ^Randall, S. K.; Bagnulo, S.; Ziegerer, E.; Geier, S.; Fontaine, G. (2015). "The Enigma tic He-sdB pulsator LS IV-14°116: New insights from the VLT".Astronomy & Astrophysics.576:A65.arXiv:1502.05520.Bibcode:2015A&A...576A..65R.doi:10.1051/0004-6361/201425251.S2CID54615595.
- ^Ahmad, A.; Jeffery, C. S. (2005)."Discovery of pulsation in a helium-rich subdwarf B star".Astronomy and Astrophysics.437(3): L51.Bibcode:2005A&A...437L..51A.doi:10.1051/0004-6361:200500136.
- ^abGreen, E. M.; Guvenen, B.; O'Malley, C. J.; O'Connell, C. J.; Baringer, B. P.; Villareal, A. S.; Carleton, T. M.; Fontaine, G.; Brassard, P.; Charpinet, S. (2011). "The Unusual Variable Hot B Subdwarf LS IV-14°116".The Astrophysical Journal.734(1): 59.Bibcode:2011ApJ...734...59G.doi:10.1088/0004-637X/734/1/59.S2CID122292750.
- ^abNaslim, N.; Jeffery, C. S.; Behara, N. T.; Hibbert, A. (2011)."An extremely peculiar hot subdwarf with a 10 000-fold excess of zirconium, yttrium and strontium".Monthly Notices of the Royal Astronomical Society.412(1): 363.arXiv:1010.5146.Bibcode:2011MNRAS.412..363N.doi:10.1111/j.1365-2966.2010.17909.x.S2CID118469201.
- ^Miller Bertolami, M. M.; Córsico, A. H.; Althaus, L. G. (2011). "On the Challenging Variability of LS IV-14°116: Pulsational Instabilities Excited by the epsilon-Mechanism".The Astrophysical Journal Letters.741(1): L3.arXiv:1109.4943.Bibcode:2011ApJ...741L...3M.doi:10.1088/2041-8205/741/1/L3.S2CID118525163.