Rotation and magnetism in white dwarfs

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/169559· OSTI ID:6105232

Schmidt, G D; Norsworthy, J E ^[1]

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1. Steward Observatory, Tucson, AZ (USA)

New rotational ephemerides for four isolated magnetic white dwarfs are derived from more than a decade of polarimetric monitoring. The stars span the period range 99 min-17.9 days and effectively double the number of white dwarfs with measured rotation periods. In addition, five stars whose polarization is constant on time scales up to at least 10 years may have very long rotation periods (P greater than about 100 yr). The lack of very short period white dwarfs attests to the coupling of angular momentum into the giant envelope or interstellar medium during late stages of evolution, but thus far there is no evidence that this process involves magnetic braking. With few exceptions, the disk-averaged fields of magnetic degenerates are dominated by dipolar patterns (as opposed to higher order multipoles or spots), and cover a broad range of obliquity to the rotation axis. 30 refs.

• OSTI ID: 6105232
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 366; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANGULAR MOMENTUM
DWARF STARS
INTERSTELLAR SPACE
MAGNETIC FIELDS
MAGNETIC STARS
MOTION
POLARIMETRY
POLARIZATION
ROTATION
SPACE
STAR EVOLUTION
STARS
WHITE DWARF STARS