ZhETF, Vol. 122,
No. 5,
p. 915 (November 2002)
(English translation - JETP,
Vol. 95, No. 5,
p. 789,
November 2002
available online at www.springer.com
)
ELECTROMAGNETIC ACTIVITY OF A PULSATING PARAMAGNETIC NEUTRON STAR
Bastrukov S.I., Podgainy D.V., Yang J., Weber F.
Received: June 10, 2002
PACS: 26.60.+c, 26.50.+x, 52.35.Bj, 52.30.Db
The fact that neutron star matter possesses the capability of maintaining a highly intense magnetic field has been and still is among the most debatable issues in pulsar astrophysics. Over the years, there were several independent suggestions that the dominant source of pulsar magnetism is either the field-induced or the spontaneous magnetic polarization of the baryon material. The Pauli paramagnetism of degenerate neutron matter is one of the plausible and comprehensive mechanisms of the magnetic ordering of neutron magnetic moments, promoted by a seed magnetic field inherited by the neutron star from a massive progenitor and amplified by its implosive contraction due to the magnetic flux conservation. Adhering to this attitude and based on the equations of magneto-elastic dynamics underlying continuum mechanics of single-axis magnetic insulators, we investigate electrodynamics of a paramagnetic neutron star undergoing nonradial pulsations. We show that the suggested approach regains a recent finding of Akhiezer, Laskin, and Peletminskii [1] that the spin-polarized neutron matter can transmit perturbations by low-frequency transverse magneto-elastic waves. We found that nonradial torsional magneto-elastic pulsations of a paramagnetic neutron star can serve as a powerful generator of a highly intense electric field producing the magnetospheric polarization charge whose acceleration along the open magnetic field lines leads to the synchrotron and curvature radiation. Analytic and numerical estimates for periods of nonradial torsional magneto-elastic modes are presented and are followed by a discussion of their possible manifestation in currently monitored activity of pulsars and magnetars.
|
|