English
Related papers

Related papers: Pulsars and Redshifts

200 papers

A hypothetical time-variation of the gravitational constant $G$ would make neutron stars expand or contract, so the matter in their interiors would depart from beta equilibrium. This induces non-equilibrium weak reactions, which release…

High Energy Astrophysical Phenomena · Physics 2009-11-03 Andreas Reisenegger , Paula Jofré , Rodrigo Fernández

Contrary to young neutron stars, young strange stars are not subject to the r-mode instability which slows rapidly rotating, hot neutron stars to rotation periods near 10 ms via gravitational wave emission. Young millisecond pulsars are…

Astrophysics · Physics 2009-10-30 Jes Madsen

We demonstrate that rotational superradiance can be efficient in millisecond pulsars. Measurements from the two fastest known pulsars PSR J1748-2446ad and PSR B1937+21 can place bounds on bosons with masses below 10^{-11} eV. The bounds are…

High Energy Physics - Phenomenology · Physics 2019-08-29 David E. Kaplan , Surjeet Rajendran , Paul Riggins

The discovery of two neutron stars with gravitational masses $\approx 2~M_\odot$ has placed a strong lower limit on the maximum mass of nonrotating neutron stars, and with it a strong constraint on the properties of cold matter beyond…

High Energy Astrophysical Phenomena · Physics 2015-08-19 Scott Lawrence , Justin G. Tervala , Paulo F. Bedaque , M. Coleman Miller

Observations using the Rossi X-ray Timing Explorer have discovered dozens of accreting neutron stars with millisecond spin periods in low-mass binary star systems. Eighteen are millisecond X-ray pulsars powered by accretion or nuclear…

Astrophysics · Physics 2009-11-11 Frederick K. Lamb

Almost 50 years after radio pulsars were discovered in 1967, our understanding of these objects remains incomplete. On the one hand, within a few years it became clear that neutron star rotation gives rise to the extremely stable sequence…

High Energy Astrophysical Phenomena · Physics 2015-06-29 V. S. Beskin , S. V. Chernov , C. R. Gwinn , A. Tchekhovskoy

In proto-neutron stars with strong magnetic fields, the cross section for $\nu_e$ ($\bar\nu_e$) absorption on neutrons (protons) depends on the local magnetic field strength due to the quantization of energy levels for the $e^-$ ($e^+$)…

Astrophysics · Physics 2009-10-30 Dong Lai , Y. -Z. Qian

Neutron stars are the most compact horizonless objects in the Universe, exhibiting the strongest known magnetic fields. They are potential sources of coincident gravitational waves and electromagnetic radiation across the entire spectrum.…

High Energy Astrophysical Phenomena · Physics 2025-08-29 Fabrizio Venturi Piñas , Anson Ka Long Yip , Patrick Chi-Kit Cheong , Milton Ruiz

Gravitational radiation (GR) drives an instability in certain modes of rotating stars. This instability is strong enough in the case of the r-modes to cause their amplitudes to grow on a timescale of tens of seconds in rapidly rotating…

Astrophysics · Physics 2007-05-23 Lee Lindblom

Neutron stars can have, in some phases of their life, extremely strong magnetic fields, up to 10^15-10^16 G. These objects, named magnetars, could be powerful sources of gravitational waves, since their magnetic field could determine large…

Solar and Stellar Astrophysics · Physics 2015-05-20 L. Gualtieri , R. Ciolfi , V. Ferrari

We examine the effects of a relativistic wind on the spin down of a neutron star and apply our results to the study of Soft Gamma Repeaters (SGRs), thought to be neutron stars with magnetic fields > 10^{14} G. We derive a spin-down formula…

Astrophysics · Physics 2009-10-31 Alice K. Harding , Ioannis Contopoulos , Demosthenes Kazanas

New data imply that the average velocity of radio pulsars is large \cite{hla93}. Under the assumption that these data imply that a pulsar is born with an ``intrinsic'' kick, we investigate whether such kicks can be a consequence of…

Astrophysics · Physics 2009-01-23 Adam Burrows , John Hayes

Highly magnetized neutron stars (NSs) are characterized by a bewildering range of astrophysical manifestations. Here, building on our simulations of the evolution of magnetic stresses in the NS crust and its ensuing fractures (Perna & Pons…

High Energy Astrophysical Phenomena · Physics 2012-03-28 Jose A. Pons , Rosalba Perna

We report results of the spectral and timing analysis of the Be/X-ray pulsar SXP 4.78 using the data obtained during its recent outburst with NuSTAR, Swift, Chandra and NICER observatories. Using an overall evolution of the system…

The recent discovery of the "weak field, old magnetar", the soft gamma repeater SGR 0418+5729, whose dipole magnetic field is less than 7.5 \times 10^{12} G, has raised perplexing questions: How can the neutron star produce SGR-like bursts…

High Energy Astrophysical Phenomena · Physics 2015-05-30 S. Dall'Osso , J. Granot , T. Piran

Continuous wave gravitational radiation from isolated rotating neutron stars is discussed. The general waveform and orders of magnitude for the amplitude are presented for various known pulsars. The specific case of gravitational radiation…

Astrophysics · Physics 2007-05-23 E. Gourgoulhon , S. Bonazzola

Pulsars, especially millisecond pulsars, are intrinsically very stable celestial clocks, and their great pulse period stability open up a wide range of potential applications to astronomical phenomena, such as a natural detector for very…

High Energy Astrophysical Phenomena · Physics 2014-12-10 Joan Jing Wang , Hsiang-Kuang Chang

Estimates of the magnetic field of neutron stars in X-ray pulsars are obtained using the hypothesis of the equilibrium period for disk and wind accretion and also from the BATSE data on timing of X-ray pulsars using the observed maximum…

Astrophysics · Physics 2016-08-30 S. B. Popov , V. M. Lipunov

Many physically motivated extensions to general relativity (GR) predict significant deviations in the properties of spacetime surrounding massive neutron stars. We report the measurement of a 2.01 +/- 0.04 solar mass pulsar in a 2.46-hr…

The Chandrasekhar mass limit sets the scale for the late evolutionary stages of massive stars, including the formation of neutron stars in core collapse supernovae. Because its value depends on the gravitational constant G, the masses of…

Astrophysics · Physics 2009-10-28 S. E. Thorsett