The Pulsed Spectra of Two Extraordinary Pulsars

Mallory S. E. Roberts; Scott M. Ransom; Fotis Gavriil; Victoria M. Kaspi; Pete Woods; Alaa Ibrahim; Craig Markwardt; Jean H. Swank

doi:10.1063/1.1781046

arXiv · astro-ph/0401111

The Pulsed Spectra of Two Extraordinary Pulsars

Mallory S. E. Roberts·Scott M. Ransom·Fotis Gavriil·Victoria M. Kaspi·Pete Woods·Alaa Ibrahim·Craig Markwardt·Jean H. Swank

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Abstract

We report on X-ray monitoring of two isolated pulsars within the same RXTE field of view. PSR J1811-1925 in the young supernova remnant G11.2-0.3 has a nearly sinusoidal pulse profile with a hard pulsed spectrum (photon index \~1.2). The pulsar is a highly efficient (~ 1% of spin-down energy) emitter of 2-50 keV pulsed X-rays despite having a fairly typical B ~ 2e12 G magnetic field. PSR J1809-1943/XTE J1810-197 is a newly discovered slow (P=5.54 s), apparently isolated X-ray pulsar which increased in flux by a factor of ~100 in 2003 January. Nine months of monitoring observations have shown a decrease in pulsed flux of ~ 30% without a significant change in its apparently thermal spectrum (kT ~0.7 keV) or pulse profile. During this time, the spin-down torque has fluctuated by a factor of ~ 2. Both the torque and the flux have remained steady for the last 3 months, at levels consistent with a magnetar interpretation.

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Mallory S. E. Roberts, Scott M. Ransom, Fotis Gavriil, Victoria M. Kaspi, Pete Woods, Alaa Ibrahim, Craig Markwardt, Jean H. Swank. 2004-01-08. The Pulsed Spectra of Two Extraordinary Pulsars. https://doi.org/10.1063/1.1781046

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