Przybylski's Star

HD 101065
Observation data
Epoch J2000      Equinox J2000
Constellation Centaurus
Right ascension 11h 37m 37.04050s[1]
Declination –46° 42′ 34.8768″[1]
Apparent magnitude (V) 8.02[2] (7.996 - 8.020[3])
Characteristics
Spectral type F3 Ho[4]
U−B color index +0.20[2]
B−V color index +0.76[2]
Variable type roAp[3]
Astrometry
Radial velocity (Rv)+10.2[5] km/s
Proper motion (μ) RA: –47.36[1] mas/yr
Dec.: +34.44[1] mas/yr
Parallax (π)8.93 ± 0.87[1] mas
Distance370 ± 40 ly
(110 ± 10 pc)
Details
Mass4.0 ± 0.1[6] M☉
Radius1.90[7] R☉
Surface gravity (log g)4.2[8] cgs
Temperature6,600[8] K
Metallicity [Fe/H]–2.40[9] dex
Age56.6 ± 27.9[6] Myr
Other designations
V816 Cen, CD−46&°7232, HD 101065, HIP 56709, SAO 222918.[10]

Przybylski's Star /ʃᵻˈbɪlskiz stɑːr/, or HD 101065, is a rapidly oscillating Ap star that is located at a distance of roughly 370 light-years (110 parsecs) from the Sun in the southern constellation of Centaurus.

Scientific history

In 1961, the Polish-Australian astronomer Antoni Przybylski (Polish pronunciation [ˈantɔɲi pʂɨˈbɨlski]) discovered that this star had a peculiar spectrum that would not fit into the standard framework for stellar classification.[5] Przybylski's observations indicated unusually low amounts of iron and nickel in the star's spectrum, but higher amounts of unusual elements like strontium, holmium, niobium, scandium, yttrium, caesium, neodymium, praseodymium, thorium, ytterbium, and uranium. In fact, at first Przybylski doubted that iron was present in the spectrum at all. Modern work shows that the iron-group elements are somewhat below normal in abundance, but it is clear that the lanthanides and other exotic elements are highly overabundant. Lanthanide elements are from 1000 to 10,000 times more abundant than in the Sun. As a result of these peculiar abundances this star belongs firmly in the Ap star class.

Przybylski's Star also contains many different short-lived actinide elements with actinium, protactinium, neptunium, plutonium, americium, curium, berkelium, californium, and einsteinium being detected. Other radioactive elements discovered in this star include technetium and promethium.[11]

Compared to neighboring stars, HD 101065 has a high peculiar velocity of 23.8 ± 1.9 km s−1.[6]

Properties

HD 101065 is the prototype star of the roAp star class. In 1978, it was discovered to pulsate photometrically with a period of 12.15 min.[12]

A companion has also been detected, a 14th magnitude star (in infrared) 8 arc seconds away. This would be a separation of nearly 1,000 AU, but there is a possibility that it is an unrelated star in a chance alignment.[13]

See also

References

  1. 1 2 3 4 5 van Leeuwen, Floor (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752v1Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357 Note: see VizieR catalogue I/311.
  2. 1 2 3 Wegner, G. (1976). "On the reddening and the effective temperature of HD 101065". Monthly Notices of the Royal Astronomical Society. 177: 99–108. Bibcode:1997A&A...323L..49P. doi:10.1093/mnras/177.1.99.
  3. 1 2 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/gcvs. Originally published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  4. ↑ Renson, P.; Manfroid, J. (2009). "Catalogue of Ap, Hg Mn and Am stars". Astronomy and Astrophysics. 498 (3): 961. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788.
  5. 1 2 Przybylski, A.; Kennedy, P. Morris (August 1963). "The Spectrum of HD 101065". Publications of the Astronomical Society of the Pacific. 75 (445): 349–353. Bibcode:1963PASP...75..349P. doi:10.1086/127965.
  6. 1 2 3 Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883Freely accessible, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x
  7. ↑ Shulyak, D.; Ryabchikova, T.; Kildiyarova, R.; Kochukhov, O. (2010). "Realistic model atmosphere and revised abundances of the coolest Ap star HD 101065". Astronomy and Astrophysics. 520: A88. arXiv:1004.0246Freely accessible. Bibcode:2010A&A...520A..88S. doi:10.1051/0004-6361/200913750.
  8. 1 2 Cowley, C. R.; Ryabchikova, T.; Kupka, F.; Bord, D. J.; Mathys, G.; Bidelman, W. P. (2000). "Abundances in Przybylski's star". Monthly Notices of the Royal Astronomical Society. 317 (2): 299–309. Bibcode:2000MNRAS.317..299C. doi:10.1046/j.1365-8711.2000.03578.x.
  9. ↑ Przybylski, A. (January 1977). "Is iron present in the atmosphere of HD 101065". Monthly Notices of the Royal Astronomical Society. 178 (2): 71–84. Bibcode:1977MNRAS.178...71P. doi:10.1093/mnras/178.2.71.
  10. ↑ "V816 Cen -- Variable Star". SIMBAD Astronomical Object Database. Centre de Données astronomiques de Strasbourg. Retrieved 2008-06-06.
  11. ↑ Gopka, V. F.; Yushchenko, A. V.; Yushchenko, V. A.; Panov, I. V.; Kim, Ch. (15 May 2008). "Identification of absorption lines of short half-life actinides in the spectrum of Przybylski's star (HD 101065)". Kinematics and Physics of Celestial Bodies. 24 (2): 89–98. Bibcode:2008KPCB...24...89G. doi:10.3103/S0884591308020049.
  12. ↑ Kurtz, D. W. (1978). "12.15 Minute Light Variations in Przybylski's Star, HD 101065". Information Bulletin on Variable Stars. 1436: 1. Bibcode:1978IBVS.1436....1K.
  13. ↑ Schöller, M.; Correia, S.; Hubrig, S.; Kurtz, D. W. (2012). "Multiplicity of rapidly oscillating Ap stars". Astronomy & Astrophysics. 545: A38. arXiv:1208.0480Freely accessible. Bibcode:2012A&A...545A..38S. doi:10.1051/0004-6361/201118538.
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