HL Tau 76


HL Tau 76
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Taurus
Right ascension 04h 18m 56.46s[1]
Declination +27° 17′ 51.4″[1]
Apparent magnitude (V) 14.1–15.28[2]
Spectral type DAV5[3]
B−V color index 0.2[1]
Variable type DAV (ZZ Ceti)[2]
Proper motion (μ) RA: 66[1] mas/yr
Dec.: −72[1] mas/yr
Other designations
EGGR 265, V411 Tau, WD 0416+272[1]
Database references

HL Tau 76 is a variable white dwarf star of the DAV (or ZZ Ceti) type. It was observed by G. Haro and W. J. Luyten in 1961,[4][5] and was the first variable white dwarf discovered when, in 1968, Arlo U. Landolt found that it varied in brightness with a period of approximately 749.5 seconds, or 12.5 minutes.[5] Like other DAV white dwarfs, its variability arises from non-radial gravity wave pulsations within itself.[6], § 7. Later observation and analysis has found HL Tau 76 to pulsate in over 40 independent vibrational modes, with periods between 380 seconds and 1390 seconds.[7]

Notes and references

  1. ^ a b c d e f "HL Tau 76". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved June 12, 2007.
  2. ^ a b Combined General Catalogue of Variable Stars (GCVS), v. 4.2. CDS ID II/250.
  3. ^ A Catalog of Spectroscopically Identified White Dwarfs, George P. McCook and Edward M. Sion, Astrophysical Journal Supplement 121, #1 (March 1999), pp. 1–130. CDS ID III/210.
  4. ^ (in Spanish) Nueva estrella enana blanca en las nubes obscuras del Toro, G. Haro and W. J. Luyten, Bol. Obs. Tonantzintla y Tacubaya 3, 35, no. 21.
  5. ^ a b A New Short-Period Blue Variable, Arlo U. Landolt, Astrophysical Journal 153, #1 (July 1968), pp. 151–164.
  6. ^ Physics of white dwarf stars, D. Koester and G. Chanmugam, Reports on Progress in Physics 53 (1990), pp. 837–915.
  7. ^ Whole Earth telescope observations of the ZZ Ceti star HL Tau 76, N. Dolez, G. Vauclair, G., S. J. Kleinman, M. Chevreton, J. N. Fu, J.-E. Solheim, J. M. González Perez, A. Ulla, L. Fraga, A. Kanaan, M. Reed, S. Kawaler, M. S. O'Brien, T. S. Metcalfe, R. E. Nather, D. Sanwal, E. W. Klumpe, A. Mukadam, M. A. Wood, T. J. Ahrens, N. Silvestri, D. Sullivan, T. Sullivan, X. J. Jiang, D. W. Xu, B. N. Ashoka, E. Leibowitz, P. Ibbetson, E. Ofek, D. Kilkenny, E. G. Meištas, D. Alisauskas, R. Janulis, R. Kalytis, P. Moskalik, S. Zola, J. Krzesinski, W. Ogloza, G. Handler, R. Silvotti, and S. Bernabei, Astronomy and Astrophysics 446, #1 (January 2006), pp. 237–257.