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Related papers: A Core-envelope Analytic Model for the Vela Pulsar

200 papers

We perform a systematic assessment of models for the equation of state (EOS) of dense matter in the context of recent neutron star mass and radius measurements to obtain a broad picture of the structure of neutron stars. We demonstrate that…

Nuclear Theory · Physics 2015-01-27 Andrew W. Steiner , Stefano Gandolfi , Farrukh J. Fattoyev , William G. Newton

If the causality condition [the speed of sound always remains less than that of light in vacuum, i. e., $v \leq c = 1$] is imposed on the spheres of homogeneous energy density, the `ratio of the specific heats', $\gamma \leq 2.59457$,…

Astrophysics · Physics 2016-08-30 P. S. Negi

Many pulsars are observed to "glitch", i.e. show sudden jumps in their rotational frequency $\nu$, some of which can be as large as $\Delta \nu/\nu\approx 10^{-6}-10^{-5}$ in a subset of pulsars known as giant glitchers. Recently Pizzochero…

Solar and Stellar Astrophysics · Physics 2015-06-05 Stefano Seveso , Pierre M. Pizzochero , Brynmor Haskell

We use models of magnetized hydrogen atmospheres to fit the soft X-ray thermal spectrum of the Vela pulsar obtained by ROSAT. The distance and hydrogen column density required by our fits are in good agreement with other independents…

Astrophysics · Physics 2007-05-23 Dany Page , Yu. A. Shibanov , V. E. Zavlin

Fallback disks are expected to form around young neutron stars. The presence of these disks can be revealed by their blackbody spectrum in the infrared, optical and UV bands. We present a re-reduction of the archival optical and infrared…

High Energy Astrophysical Phenomena · Physics 2014-11-10 Gökçe Özsükan , K. Yavuz Ekşi , Valeri Hambaryan , Ralph Neuhäuser , Markus M. Hohle , Christian Ginski , Klaus Werner

Observations of pulsar glitches may provide insights on the internal physics of neutron stars and recent studies show how it is in principle possible to constrain pulsar masses with timing observations. The reliability of these estimates…

High Energy Astrophysical Phenomena · Physics 2020-02-12 Alessandro Montoli , Marco Antonelli , Pierre Pizzochero

Many pulsars exhibit a peculiar behaviour in their pulse profile of a sudden increase in their rotational period, which is popularly known as a pulsar glitch. Some of them show giant glitches with relative amplitude $\Delta\Omega/\Omega…

High Energy Astrophysical Phenomena · Physics 2026-05-05 Yogeesh N. , Anil Kumar , Monika Sinha

Giant pulsar frequency glitches as detected in the emblematic Vela pulsar have long been thought to be the manifestation of a neutron superfluid permeating the inner crust of a neutron star. However, this superfluid has been recently found…

High Energy Astrophysical Phenomena · Physics 2016-07-27 T. Delsate , N. Chamel , N. Gürlebeck , A. F. Fantina , J. M. Pearson , C. Ducoin

We show that the widely used parabolic approximation to the Equation of State (EOS) of asymmetric nuclear matter leads systematically to significantly higher core-crust transition densities and pressures. Using an EOS for neutron-rich…

Nuclear Theory · Physics 2010-03-04 Lie-Wen Chen , Bao-An Li , Hong-Ru Ma , Jun Xu

We present a systematic study of the properties of pure hadronic and hybrid compact stars. The nuclear equation of state (EoS) for beta-equilibrated neutron star matter was obtained using density dependent effective nucleon-nucleon…

Nuclear Theory · Physics 2015-03-19 Abhishek Mishra , Partha Roy Chowdhury , D. N. Basu

We use two-dimensional hydrodynamical simulations to investigate the properties of dense ejecta clumps (bullets) in a core collapse supernova remnant, motivated by the observation of protrusions probably caused by clumps in the Vela…

Astrophysics · Physics 2009-11-07 Chih-Yueh Wang , Roger A. Chevalier

In this work we present a revised measurement of the phase-averaged optical polarisation of the Vela pulsar (PSR B0833-45), for which only one value has been published so far (Wagner & Seifert 2000). Our measurement has been obtained…

Astrophysics · Physics 2009-11-13 R. P. Mignani , S. Bagnulo , J. Dyks , G. Lo Curto , A. Slowikowska

Pulsars are known for their superb timing precision, although glitches can interrupt the regular timing behavior when the stars are young. These glitches are thought to be caused by interactions between normal and superfluid matter in the…

Solar and Stellar Astrophysics · Physics 2015-10-05 Wynn C. G. Ho , Cristobal M. Espinoza , Danai Antonopoulou , Nils Andersson

Pulsars are neutron stars, stellar corpses left over after supernova explosions of stars about ten times as massive as our Sun, with densities comparable to the atomic nucleus', spinning with periods from few milliseconds up to few seconds,…

We measured the radial-velocity curve of HD77581, the B-supergiant companion of the X-ray pulsar Vela X-1, using 183 high-resolution optical spectra obtained in a nine-month campaign. We derive radial-velocity amplitudes for different lines…

Astrophysics · Physics 2009-11-07 O. Barziv , L. Kaper , M. H. van Kerkwijk , J. H. Telting , J. van Paradijs

High resolution, pulse to pulse observation of the 2016 Vela glitch and its relaxation provided an opportunity to probe the neutron star internal structure and dynamics with unprecedented detail. We use the observations of this glitch to…

High Energy Astrophysical Phenomena · Physics 2020-07-08 Erbil Gügercinoğlu , M. Ali Alpar

Polarisation measurements of pulsars offer an unique insight into the geometry of the emission regions in the neutron star magnetosphere. Therefore, they provide observational constraints on the different models proposed for the pulsar…

High Energy Astrophysical Phenomena · Physics 2014-09-08 P. Moran , R. P. Mignani , A. Shearer

Pulsars show two classes of rotational irregularities that can be used to understand neutron-star interiors and magnetospheres: glitches and timing noise. Here we present an analysis of the Vela pulsar spanning nearly 21 yr of observation…

High Energy Astrophysical Phenomena · Physics 2016-04-27 R. M. Shannon , L. T. Lentati , M. Kerr , S. Johnston , G. Hobbs , R. N. Manchester

Using a novel technique, we achieve ~100 picoarcsecond resolution and set an upper bound of less than 4 km for the characteristic size of the Vela pulsar's emission region. Specifically, we analyze flux-density statistics of the Vela pulsar…

Solar and Stellar Astrophysics · Physics 2012-09-20 Michael D. Johnson , Carl R. Gwinn , Paul Demorest

Glitches are sudden increases in the rotation rate $\nu$ of neutron stars, which are thought to be driven by the neutron superfluid inside the star. The Vela pulsar presents a comparatively high rate of glitches, with 21 events reported…

High Energy Astrophysical Phenomena · Physics 2021-05-05 C. M. Espinoza , D. Antonopoulou , R. Dodson , M. Stepanova , A. Scherer