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An x-ray pulsar with a superstrong magnetic field in the soft gamma-ray repeater sgr1806-20
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Smith, I. Kouveliotou, C. Strohmayer, T. Kommers, J. Frail, D. Murakami, T. Dieters, S. vanParadijs, J. Hurley, K. Fishman, G. J. Meegan, C. A. |
| Copyright Year | 1998 |
| Description | Soft gamma-ray repeaters (SGRs) emit multiple, brief (approximately O.1 s) intense outbursts of low-energy gamma-rays. They are extremely rare; three are known in our galaxy and one in the Large Magellanic Cloud. Two SGRs are associated with young supernova remnants (SNRs), and therefore most probably with neutron stars, but it remains a puzzle why SGRs are so different from 'normal' radio pulsars. Here we report the discovery of pulsations in the persistent X-ray flux of SGR1806-20, with a period of 7.47 s and a spindown rate of 2.6 x 10(exp -3) s/yr. We argue that the spindown is due to magnetic dipole emission and find that the pulsar age and (dipolar) magnetic field strength are approximately 1500 years and 8 x 10(exp 14) gauss, respectively. Our observations demonstrate the existence of 'magnetars', neutron stars with magnetic fields about 100 times stronger than those of radio pulsars, and support earlier suggestions that SGR bursts are caused by neutron-star 'crust-quakes' produced by magnetic stresses. The 'magnetar' birth rate is about one per millenium, a substantial fraction of that of radio pulsars. Thus our results may explain why some SNRs have no radio pulsars. |
| File Size | 306894 |
| Page Count | 3 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19990007784 |
| Archival Resource Key | ark:/13960/t1gj4f46h |
| Language | English |
| Publisher Date | 1998-05-21 |
| Access Restriction | Open |
| Subject Keyword | Astrophysics Gamma Rays Supernova Remnants Neutron Stars Magellanic Clouds X Rays Magnetic Dipoles Pulsars Repeaters Unsteady Flow Magnetic Fields Crusts Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
