An X-ray pulsar with a superstrong magnetic field in the soft γ-ray repeater SGR1806 − 20
TL;DR: In this paper, the authors reported 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.
Abstract: 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.
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TL;DR: A new and complete catalog of the main properties of the 1509 pulsars for which published information currently exists, which includes all spin-powered pulsars, as well as anomalous X-ray pulsars and soft gamma-ray repeaters showing coherent pulsed emission.
Abstract: We have compiled a new and complete catalog of the main properties of the 1509 pulsars for which published information currently exists. The catalog includes all spin-powered pulsars, as well as anomalous X-ray pulsars and soft gamma-ray repeaters showing coherent pulsed emission, but excludes accretion-powered systems. References are given for all data listed. We have also developed a new World Wide Web interface for accessing and displaying either tabular or plotted data with the option of selecting pulsars to be displayed via logical conditions on parameter expressions. The Web interface has an expert mode giving access to a wider range of parameters and allowing the use of custom databases. For users with locally installed software and database on Unix or Linux systems, the catalog may be accessed from a command-line interface. C-language functions to access specified parameters are also available. The catalog is updated from time to time to include new information.
2,985 citations
TL;DR: In this paper, the authors present a very crude model of the phenomenon, and simple analytical formulae that can be used to estimate the parameters of a transient as a function of poorly known input parameters.
Abstract: Mergers of neutron stars (NS + NS) or neutron stars and stellar-mass black holes (NS + BH) eject a small fraction of matter with a subrelativistic velocity. Upon rapid decompression, nuclear-density medium condenses into neutron-rich nuclei, most of them radioactive. Radioactivity provides a long-term heat source for the expanding envelope. A brief transient has a peak luminosity in the supernova range, and the bulk of radiation in the UV-optical domain. We present a very crude model of the phenomenon, and simple analytical formulae that can be used to estimate the parameters of a transient as a function of poorly known input parameters. The mergers may be detected with high-redshift supernova searches as rapid transients, many of them far away from the parent galaxies. It is possible that the mysterious optical transients detected by Schmidt et al. are related to neutron star mergers, since they typically have no visible host galaxy.
1,246 citations
TL;DR: A review of nearly a decade of short gamma-ray bursts and their afterglow and host-galaxy observations is presented in this article, where the authors use this information to shed light on the nature and properties of their progenitors, the energy scale and collimation of the relativistic outflow, and the properties of the circumburst environments.
Abstract: Gamma-ray bursts (GRBs) display a bimodal duration distribution with a separation between the short- and long-duration bursts at about 2 s. The progenitors of long GRBs have been identified as massive stars based on their association with Type Ic core-collapse supernovae (SNe), their exclusive location in star-forming galaxies, and their strong correlation with bright UV regions within their host galaxies. Short GRBs have long been suspected on theoretical grounds to arise from compact object binary mergers (neutron star–neutron star or neutron star–black hole). The discovery of short GRB afterglows in 2005 provided the first insight into their energy scale and environments, as well as established a cosmological origin, a mix of host-galaxy types, and an absence of associated SNe. In this review, I summarize nearly a decade of short GRB afterglow and host-galaxy observations and use this information to shed light on the nature and properties of their progenitors, the energy scale and collimation of the relativistic outflow, and the properties of the circumburst environments. The preponderance of the evidence points to compact object binary progenitors, although some open questions remain. On the basis of this association, observations of short GRBs and their afterglows can shed light on the on- and off-axis electromagnetic counterparts of gravitational wave sources from the Advanced LIGO/Virgo experiments.
1,061 citations
Cites background from "An X-ray pulsar with a superstrong ..."
...…(SGRs; e.g.,Kouveliotou et al. 1987, Laros et al. 1987, Norris et al. 1991), which originate from magnetars in the Milky Way and nearbygalaxies (Kouveliotou et al. 1998); it is important to note, however, that some events classified as short GRBs may represent extragalactic giant SGR flares…...
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TL;DR: In this article, the authors investigate how current and proposed observations of neutron stars can lead to an understanding of the state of their interiors and the key unknowns: the typical neutron star radius and the neutron star maximum mass.
1,024 citations
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...Our observations demonstrate the existence of ‘magnetars’, neutron stars with magnetic fields about 100 times stronger than those of radio pulsars, and support earlier suggestion...
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TL;DR: In this article, the decay rate of the core field is a very strong function of temperature and therefore of the magnetic flux density, which is not present in the decay of the weaker fields associated with ordinary radio pulsars.
Abstract: We calculate the quiescent X-ray, neutrino, and Alfven wave emission from a neutron star with a very strong magnetic field, Bdipole ~ 1014 − 1015 G and Binterior ~ (5–10) × 1015 G. These results are compared with observations of quiescent emission from the soft gamma repeaters and from a small class of anomalous X-ray pulsars that we have previously identified with such objects. The magnetic field, rather than rotation, provides the main source of free energy, and the decaying field is capable of powering the quiescent X-ray emission and particle emission observed from these sources. New features that are not present in the decay of the weaker fields associated with ordinary radio pulsars include fracturing of the neutron star crust, strong heating of its core, and effective suppression of thermal conduction perpendicular to the magnetic field. As the magnetic field is forced through the crust by diffusive motions in the core, multiple small-scale fractures are excited, as well as a few large fractures that can power soft gamma repeater bursts. The decay rate of the core field is a very strong function of temperature and therefore of the magnetic flux density. The strongest prediction of the model is that these sources will show no optical emissions associated with X-ray heating of an accretion disk.
1,128 citations
Book•
15 Nov 1990
TL;DR: The theory of neutron star magnetospheres is presented with reference to the most important observational data on neutron stars available to date in this paper, where attention is given to the nature of pulsars and pulsar properties and statistics; phenomenological models; aligned rotator and oblique rotator models; the disk models; alternative models; and radio emission models.
Abstract: The theory of neutron star magnetospheres is presented with reference to the most important observational data on neutron stars available to date. In particular, attention is given to the nature of pulsars and pulsar properties and statistics; phenomenological models; the aligned rotator and oblique rotator models; the disk models; alternative models; and radio emission models. The discussion also covers winds and jets from pulsars; pulsating X-ray sources; gamma-ray burst sources; and other phenomena driven by neutron stars.
555 citations
"An X-ray pulsar with a superstrong ..." refers background in this paper
...Because in this model rotational losses do operate on the neutron star, we can estimate thespindown pulsar age, τ, and magnetic field, B , from its period and period derivative, according t...
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01 Jan 1998
TL;DR: In this paper, the authors present a history of Neutron stars from early speculations to current problems, including the discovery of the first radio pulsar, the first detection of radio emissions from Pulsars, and the first measurement of the Vela Pulsar at MeV Energies at the PSR B0655+64.
Abstract: Preface. 1: History. The History of Neutron Stars: From Early Speculations to Current Problems F. Pacini. 2: Neutron Star Structure. Internal Constitution of Neutron and Strange Stars N.K. Glendenning. Topics in the Theory of Matter at Sub-Nuclear Densities C.J. pethick, D.G. Ravenhall. Dynamics of the Neutron Star Interior M.A. Alpar. Pulsar Magnetic Fields and Glitches M. Ruderman. 3: Radio Pulsars. Detection of Radio Emission from Pulsars: A Pulsar Observation Primer D. Bhattacharya. The Experimental Determination of the Limiting Spin Period of Neutron Stars N. D'Amico. Radio Pulsar Population Properties D.R. Lorimer. Energetic Young Radio Pulsars J.F. Bell. Young Nerutron Stars in Supernova Remnants D.A. Frail. Gamma-Ray Emission from CGRO Pulsars G. Kanbach. Time Averaged Pulse Phase Resolved Spectra of the Vela Pulsar Measured by COMPTEL at MeV Energies L. Kuiper, et al. New Views of the Vela Pulsar Jet C.B. Markwardt, H.B. OEgelman. Kinematics of Low-Mass X-Ray Binaries and Millisecond Pulsars R. Ramachandran, D. Bhattacharya. Unusual Increase in the 325 Mhz Flux Density of PSR B0655+64 T.J. Galama, et al. High-Energy Emission from Binary Pulsars M. Tavani. Relativistic Winds and Jets M. Salvati. Pulsar Electrodynamics, Atoms in Strong Magnetic Fields F. Simoes, A.A. da Costa. 4: X-Ray Binaries. Neutron Stars and Black Holes in X-Ray Binaries J. van Paradijs. Kilo-Hertz Quasi-Periodic Oscillations in Low-Mass X-Ray Binaries M. Van der Klis. Long-Term Behavior of Accretion Powered Pulsars M.H. Finger. GRO J1744-28: The Bursting Pulsar C. Kouveliotou. The 5-9 Second X-RayPulsars L. Stella, et al. First Results from a Systematic Search for New X-Ray Pulsators in ROSAT PSPC Fields S. Covino, P. Giommi. Thermonuclear Burning on Rapidly Accreting Neutron Stars L. Bildsten. Results from the PDS Experiment Aboard the BeppoSAX Satellite E. Palazzi, et al. The Astrophysical Key Source SS 433 W. Kundt. High-Energy Emission from Accreting Neutron Stars S. Zane, et al. 5: Evolution of Binaries with Compact Components. Coalescing Binary Neutron Stars F.A. Rasio. Modelling Gamma-Ray Bursts M. Tavani. The Effects of Kick Velocities on the Formation of Low-Mass X-Ray Binaries V. Kalogera. Transients and the Evolution of Low-Mass X-Ray Binaries A.R. King. An Evolutionary Picture for Short Orbital Period Millisecond Binary Pulsars E. Ergma, et al. 6: X-Rays from Single Neutron Stars. On the X-Ray Emission Properties of Rotation Powered Pulsars W. Becker, J. Trumper. Thermal Evolution of Isolated Neutron Stars D. Page. Evolution of Thermal Structure and Radiation Spectrum of Cooling Neutron Stars Yu.A. Shibanov, et al. Atomic Ionization and Opacities in Pulsar Atmospheres: Hydrogen Atmospheres J. Ventura, et al. The Observability of Old Neutron Stars Accreting the Interstellar Medium A. Treves, et al. Search for Old Neutron Stars in Molecular Clouds: Cygnus Rift and Cygnus OB7 T. Belloni, et al. Author Index. Subject Index. Object Index.
509 citations
TL;DR: In this article, the γ-ray burst detector Konus was used to detect hard X-ray bursts from the same source on 5 and 6 March, 1979, and the burst of 5 March was very intense, particularly in the initial phase and the second burst on 6 March was considerably weaker.
Abstract: The γ-ray burst detector Konus1, on the Venera 11 and Venera 12 spacecraft, detected on 5 and 6 March, 1979 two bursts of hard X rays originating from the same source. These events are quite unusual and of considerable interest. The burst of 5 March was very intense, particularly in the initial phase. This event was also observed by several other spacecraft2. The second burst on 6 March was considerably weaker. The observations reported here permitted us to obtain a detailed time structure of the bursts, to measure their energy spectra and to locate the source on the celestial sphere.
461 citations