TWISTING, RECONNECTING MAGNETOSPHERES AND MAGNETAR SPINDOWN

Journal Article · Fri Jul 20 04:00:00 EDT 2012 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/754/1/L12· OSTI ID:22047659

Parfrey, Kyle ^[1]; Beloborodov, Andrei M ^[2]; Hui, Lam ^[3]

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1. Astronomy Department, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
2. Physics Department and Columbia Astrophysics Laboratory, Columbia University, 538 West 120th Street, New York, NY 10027 (United States)
3. Institute for Strings, Cosmology, and Astroparticle Physics (ISCAP), Columbia University, New York, NY 10027 (United States)

We present the first simulations of evolving, strongly twisted magnetar magnetospheres. Slow shearing of the magnetar crust is seen to lead to a series of magnetospheric expansion and reconnection events, corresponding to X-ray flares and bursts. The axisymmetric simulations include rotation of the neutron star and the magnetic wind through the light cylinder. We study how the increasing twist affects the spindown rate of the star, finding that a dramatic increase in spindown occurs. Particularly spectacular are explosive events caused by the sudden opening of large amounts of overtwisted magnetic flux, which may be associated with the observed giant flares. These events are accompanied by a short period of ultrastrong spindown, resulting in an abrupt increase in spin period, such as was observed in the giant flare of SGR 1900+14.

• OSTI ID: 22047659
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 754; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTROPHYSICS
AXIAL SYMMETRY
COMPUTERIZED SIMULATION
COSMIC X-RAY BURSTS
GAMMA ASTRONOMY
MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETIC STARS
MAGNETOHYDRODYNAMICS
NEUTRON STARS
PULSARS
RELATIVISTIC RANGE
ROTATION
SPIN
VISIBLE RADIATION
X RADIATION