WD J2356−209

WD J2356−209
Observation data
Epoch J2000.0 (ICRS)      Equinox J2000.0 (ICRS)
Constellation Vela
Right ascension 23h 56m 45.576s[1]
Declination −20° 54′ 45.01″[1]
Characteristics
Spectral type DC[2] or DZ[3]
Astrometry
Distance211.3 ± 8.2 ly (64.8 ± 2.5 pc)[3] ly
Details
Surface gravity (log g)8.26±0.15[3] cgs
Temperature4,310±190[3] K
Age8.0±0.8[3] Gyr
Database references
SIMBADdata

WD J2356−209 (also known as WD 2354−211)[4] is a white dwarf star located 65 pc (212 ly) away from the Earth.[5] It is a very faint white dwarf, with an apparent visual magnitude of 21.03.[6] Its visible spectrum is dominated by a broad absorption feature[2] that has been attributed to pressure-broadened sodium D lines.[7] The presence of this sodium absorption feature and the detection of spectral lines from other heavy elements (calcium, iron and magnesium) indicate that the photosphere of WD J2356−209 has been polluted by a recent rocky debris accretion episode. A detailed analysis of the spectrum of WD J2356−209 shows that the accreted planetesimal was abnormally sodium-rich, containing up to ten times more sodium than calcium.[3] With an effective temperature of 4040 K, WD J2356−209 was the coolest metal-polluted white dwarf observed at the time (and also the oldest, with a white dwarf cooling age of about 8 Gyr).[3]

See also

References

  1. ^ a b Lasker, Barry M.; et al. (August 2008). "The Second-Generation Guide Star Catalog: Description and Properties". The Astronomical Journal. 136 (2): 735–766. arXiv:0807.2522. Bibcode:2008AJ....136..735L. doi:10.1088/0004-6256/136/2/735. S2CID 17641056.
  2. ^ a b Oppenheimer, B. R.; et al. (22 March 2001). "Direct Detection of Galactic Halo Dark Matter". Science. 292 (5517): 698–702. arXiv:astro-ph/0104293. Bibcode:2001Sci...292..698O. doi:10.1126/science.1059954. PMID 11264524. S2CID 18882777.
  3. ^ a b c d e f g Blouin, S.; Dufour, P.; Allard, N. F.; Salim, S.; Rich, R. M.; Koopmans, L. V. E. (February 2019). "A New Generation of Cool White Dwarf Atmosphere Models. III. WD J2356-209: Accretion of a Planetesimal with an Unusual Composition". The Astrophysical Journal. 872 (2): 188. arXiv:1902.03219. Bibcode:2019ApJ...872..188B. doi:10.3847/1538-4357/ab0081. S2CID 119017268.
  4. ^ "WD 2354-211". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-16.
  5. ^ Gaia Collaboration (2016). "The Gaia mission". Astronomy and Astrophysics. 595: A1. arXiv:1609.04153. Bibcode:2016A&A...595A...1G. doi:10.1051/0004-6361/201629272. S2CID 119229059.
  6. ^ Bergeron, P.; et al. (June 2005). "On the Interpretation of High‐Velocity White Dwarfs as Members of the Galactic Halo". The Astrophysical Journal. 625 (2): 838–848. arXiv:astro-ph/0502350. Bibcode:2005ApJ...625..838B. doi:10.1086/429715. S2CID 13868108.
  7. ^ Salim, Samir; Rich, R. Michael; Hansen, Brad M.; Koopmans, L. V. E.; Oppenheimer, Ben R.; Blandford, Roger D. (February 2004). "Cool White Dwarfs Revisited: New Spectroscopy and Photometry". The Astrophysical Journal. 601 (2): 1075–1087. arXiv:astro-ph/0308126. Bibcode:2004ApJ...601.1075S. doi:10.1086/380581. S2CID 119471977.
  8. ^ Elms, Abbigail K.; Tremblay, Pier-Emmanuel; Gänsicke, Boris T.; Koester, Detlev; Hollands, Mark A.; Gentile Fusillo, Nicola Pietro; Cunningham, Tim; Apps, Kevin (2022-12-01). "Spectral analysis of ultra-cool white dwarfs polluted by planetary debris". Monthly Notices of the Royal Astronomical Society. 517 (3): 4557–4574. arXiv:2206.05258. Bibcode:2022MNRAS.517.4557E. doi:10.1093/mnras/stac2908. ISSN 0035-8711.


Stub icon

This article about a white dwarf is a stub. You can help Wikipedia by expanding it.

Strategi Solo vs Squad di Free Fire: Cara Menang Mudah!