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Record Details

Record 13 of 51474
Wave energy in white dwarf atmospheres. I - Magnetohydrodynamic energy spectra for homogeneous DB and layered DA stars
External Online Source: doi:10.1086/165718
Author and Affiliation:
Musielak, Zdzislaw E.(NASA Marshall Space Flight Center, Huntsville, AL)
Abstract: The radiative damping of acoustic and MHD waves that propagate through white dwarf photospheric layers is studied, and other damping processes that may be important for the propagation of the MHD waves are calculated. The amount of energy remaining after the damping processes have occurred in different types of waves is estimated. The results show that lower acoustic fluxes should be expected in layered DA and homogeneous DB white dwarfs than had previously been estimated. Acoustic emission manifests itself in an enhancement of the quadrupole term, but this term may become comparable to or even lower than the dipole term for cool white dwarfs. Energy carried by the acoustic waves is significantly dissipated in deep photospheric layers, mainly because of radiative damping. Acoustically heated corona cannot exist around DA and DB white dwarfs in a range T(eff) = 10,000-30,000 K and for log g = 7 and 8. However, relatively hot and massive white dwarfs could be exceptions.
Publication Date: Nov 01, 1987
Document ID:
19880034195
(Acquired Nov 28, 1995)
Accession Number: 88A21422
Subject Category: ASTROPHYSICS
Document Type: Journal Article
Publication Information: Astrophysical Journal, Part 1 (ISSN 0004-637X); 322; 234-247
Publisher Information: United States
Contract/Grant/Task Num: NGL-22-009-015
Financial Sponsor: NASA; United States
Organization Source: NASA Marshall Space Flight Center; Huntsville, AL, United States
Massachusetts Inst. of Tech.; Cambridge, MA, United States
Description: 14p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: A STARS; B STARS; ENERGY SPECTRA; MAGNETOHYDRODYNAMIC WAVES; STELLAR ATMOSPHERES; WHITE DWARF STARS; MAGNETIC FLUX; STELLAR CORONAS
Imprint And Other Notes: Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 322, Nov. 1, 1987, p. 234-247.
Availability Source: Other Sources
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