Ultraviolet and X-ray detection of the 56 Pegasi system /K0 IIp + WD/ - Evidence for accretion of a cool stellar wind onto a white dwarf

Details Ultraviolet and X-ray detection of the 56 Pegasi system /K0 IIp + WD/ - Evidence for accretion of a cool stellar wind onto a white dwarf Ultraviolet and X-ray detection of the 56 Pegasi system /K0 IIp + WD/ - Evidence for accretion of a cool stellar wind onto a white dwarf

Dec 1982

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982apj...263..269s&link_type=abstract

Astrophysical Journal, Part 1, vol. 263, Dec. 1, 1982, p. 269-276. Grants No NAG5-82; No. NGL-06-003-057;

Astronomy and Astrophysics

Astronomy

41

Late Stars, Stellar Mass Accretion, Stellar Winds, Ultraviolet Spectra, White Dwarf Stars, X Ray Astronomy, Emission Spectra, Iue, Line Spectra, Stellar Spectra, Stellar Temperature

Scientific paper

IUE spectra of the slowly rotating mild barium star 56 Peg (HD 218356; K0 IIp) show excess continuum emission from 1300 to 2000 Å, a broad Lyα absorption feature, and emission lines usually associated with a l04-(2 × l05) K plasma. The best fit blackbody curve to the dereddened continuum gives a temperature of 32000 ± 4000 K and a radius for the object of (2.7 ± 1.0) × l09 cm, consistent with that of a white dwarf. Einstein IPC observations of this system yield Lx ≍ 3 × 1O31 ergs s-1, which is as bright as the RS CVn binary systems. The X-rays can be fitted to a bremsstrahlung spectrum with kT = 0.45 ± 0.3 keV, or a blackbody spectrum with kT ≍ 0.2 keV. Since bright X-ray and high temperature emission lines are unusual for single stars in this region of the H-R diagram, we do not believe that the 56 Peg primary has a hot corona and transition region. Instead, we propose that the observed X-ray luminosity is due to accretion onto the white dwarf of ∼0.1% of the wind from the primary, which we assume has a reasonable mass loss rate of 2 × 10-7 to 4 × l0-9 Msun yr-1. The ultraviolet emission lines likely result from reprocessed X-radiation absorbed by the wind. The Mg II K line exhibits a time-varying emission core, that may be explained by ionization of Mg+ in the wind by X-rays from the white dwarf.

Affiliated with

Also associated with

No associations

Rating

Ultraviolet and X-ray detection of the 56 Pegasi system /K0 IIp + WD/ - Evidence for accretion of a cool stellar wind onto a white dwarf does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ultraviolet and X-ray detection of the 56 Pegasi system /K0 IIp + WD/ - Evidence for accretion of a cool stellar wind onto a white dwarf, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultraviolet and X-ray detection of the 56 Pegasi system /K0 IIp + WD/ - Evidence for accretion of a cool stellar wind onto a white dwarf will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-927928