Related papers: Constraints on Torque-Reversing Accretion-Powered …

Timing of the accreting millisecond pulsar IGR J17591-2342: evidence of spin-down during accretion

We report on the phase-coherent timing analysis of the accreting millisecond X-ray pulsar IGR J17591-2342, using Neutron Star Interior Composition Explorer (NICER) data taken during the outburst of the source between 2018 August 15 and 2018…

High Energy Astrophysical Phenomena · Physics 2020-05-13 A. Sanna , L. Burderi , K. C. Gendreau , T. Di Salvo , P. S. Ray , A. Riggio , A. F. Gambino , R. Iaria , L. Piga , C. Malacaria , G. K. Jaisawal

Swings between rotation and accretion power in a millisecond binary pulsar

It is thought that neutron stars in low-mass binary systems can accrete matter and angular momentum from the companion star and be spun-up to millisecond rotational periods. During the accretion stage, the system is called a low-mass X-ray…

High Energy Astrophysical Phenomena · Physics 2014-02-07 A. Papitto , C. Ferrigno , E. Bozzo , N. Rea , L. Pavan , L. Burderi , M. Burgay , S. Campana , T. Di Salvo , M. Falanga , M. D. Filipović , P. C. C. Freire , J. W. T. Hessels , A. Possenti , S. M. Ransom , A. Riggio , P. Romano , J. M. Sarkissian , I. H. Stairs , L. Stella , D. F. Torres , M. H. Wieringa , G. F. Wong

Spin Down of Pulsations in the Cooling Tail of an X-ray Burst from 4U 1636-53

We report the discovery with the proportional counter array (PCA) onboard the Rossi X-ray Timing Explorer (RXTE) of a decrease in the frequency of X-ray brightness oscillations in the cooling tail of an X-ray burst from 4U 1636-53. This is…

Astrophysics · Physics 2009-10-31 Tod E. Strohmayer

Accretion in the spin-down regime

Accretion driven millisecond X-ray pulsars can accrete over a wide range of mass flow rates. The pulsations persist even at small accretion rates at which these objects would be expected to be in the propeller stage. We argue that the inner…

High Energy Astrophysical Phenomena · Physics 2010-10-08 K. Yavuz Eksi , Erlin Kutlu

Maser mechanism of optical pulsations from anomalous X-ray pulsar 4U0142+61

A maser curvature emission mechanism in the presence of curvature drift is used to explain the optical pulsations from anomalous X-ray pulsars. For the source of AXP0142+61,the optical pulsation occurs at the radial distance $R(\nu_M)\sim…

Astrophysics · Physics 2009-11-10 Y. LU , S. N. Zhang

X-ray Spectra and Pulse Frequency Changes in SAX J2103.5+4545

The November 1999 outburst of the transient pulsar SAX J2103.5+4545 was monitored with the large area detectors of the Rossi X-Ray Timing Explorer until the pulsar faded after a year. The 358 s pulsar was spun up for 150 days, at which…

Astrophysics · Physics 2009-11-07 A. Baykal , M. J. Stark , J. H. Swank

BeppoSAX monitoring of the ``anomalous'' X-ray pulsar 4U 0142+61

The 8.7s X-ray pulsar 4U 0142+61 was monitored by BeppoSAX between January 1997 and February 1998. This source belongs to the rapidly growing class of "anomalous" X-ray pulsars (AXPs) which have pulse periods in the 6-12s range and no…

Astrophysics · Physics 2007-05-23 G. L. Israel , T. Oosterbroek , L. Angelini , S. Campana , S. Mereghetti , A. N. Parmar , A. Segreto , L. Stella , J. van Paradijs , N. E. White

Insight-HXMT insight into switch of the accretion mode: the case of the X-ray pulsar 4U 1901+03

We use the In data collected during the 2019 outburst from X-ray pulsar 4U 1901+03 to complement the orbital parameters reported by Fermi/GBM. Using the Insight-HXMT, we examine the correlation between the derivative of the intrinsic spin…

High Energy Astrophysical Phenomena · Physics 2020-04-29 Y. L. Tuo , L. Ji , S. S. Tsygankov , T. Mihara , L. M. Song , M. Y. Ge , A. Nabizadeh , L. Tao , J. L. Qu , Y. Zhang , S. Zhang , S. N. Zhang , Q. C. Bu , L. Chen , Y. P. Xu , X. L. Cao , Y. Chen , C. Z. Liu , C. Cai , Z. Chang , G. Chen , T. X. Chen , Y. B. Chen , Y. P. Chen , W. Cui , W. W. Cui , J. K. Deng , Y. W. Dong , Y. Y. Du , M. X. Fu , G. H. Gao , H. Gao , M. Gao , Y. D. Gu , J. Guan , C. C. Guo , D. W. Han , Y. Huang , J. Huo , S. M. Jia , L. H. Jiang , W. C. Jiang , J. Jin , Y. J. Jin , L. D. Kong , B. Li , C. K. Li , G. Li , M. S. Li , T. P. Li , W. Li , X. Li , X. B. Li , X. F. Li , Y. G. Li , Z. W. Li , X. H. Liang , J. Y. Liao , B. S. Liu , G. Q. Liu , H. W. Liu , X. J. Liu , Y. N. Liu , B. Lu , F. J. Lu , X. F. Lu , Q. Luo , T. Luo , X. Ma , B. Meng , Y. Nang , J. Y. Nie , G. Ou , N. Sai , R. C. Shang , X. Y. Song , L. Sun , Y. Tan , C. Wang , G. F. Wang , J. Wang , W. S. Wang , Y. S. Wang , X. Y. Wen , B. Y. Wu , B. B. Wu , M. Wu , G. C. Xiao , S. Xiao , S. L. Xiong , J. W. Yang , S. Yang , Y. J. Yang , Y. J. Yang , Q. B. Yi , Q. Q. Yin , Y. You , A. M. Zhang , C. M. Zhang , F. Zhang , H. M. Zhang , J. Zhang , T. Zhang , W. Zhang , W. C. Zhang , W. Z. Zhang , Y. Zhang , Y. F. Zhang , Y. J. Zhang , Y. H. Zhang , Y. Zhang , Z. Zhang , Z. Zhang , Z. L. Zhang , H. S. Zhao , X. F. Zhao , S. J. Zheng , Y. G. Zheng , D. K. Zhou , J. F. Zhou , Y. X. Zhu , Y. Zhu , R. L. Zhuang

Near-periodical spin period evolution in the binary system LMC X-4

In this paper we investigated the long-term evolution of the pulse-period in the high-mass X-ray binary LMC X-4 by taking advantage of more than 43~yrs of measurements in the X-ray domain. Our analysis revealed for the first time that the…

High Energy Astrophysical Phenomena · Physics 2016-11-15 S. Molkov , A. Lutovinov , M. Falanga , S. Tsygankov , E. Bozzo

Origin of intermittent accretion-powered X-ray oscillations in neutron stars with millisecond spin periods

We have shown previously that many of the properties of persistent accretion-powered millisecond pulsars can be understood if their X-ray emitting areas are near their spin axes and move as the accretion rate and structure of the inner disk…

Astrophysics · Physics 2011-02-11 Frederick K. Lamb , Stratos Boutloukos , Sandor Van Wassenhove , Robert T. Chamberlain , Ka Ho Lo , M. Coleman Miller

Pulse Profile Change Possibly Associated with a Glitch in an Anomalous X-Ray Pulsar 4U 0142+61

We report a glitch-like pulse frequency deviation from the simple spin-down law in an anomalous X-ray pulsar (AXP) 4U 0142+61 detected by ASCA observations. We also found a significant pulse profile change after the putative glitch. The…

Astrophysics · Physics 2009-11-10 Mikio Morii , Nobuyuki Kawai , Noriaki Shibazaki

An observational argument against accretion in magnetars

The phenomenology of anomalous X-ray pulsars is usually interpreted within the paradigm of very highly magnetized neutron stars, also known as magnetars. According to this paradigm, the persistent emission of anomalous X-ray pulsars (AXPs)…

High Energy Astrophysical Phenomena · Physics 2020-11-25 Victor Doroshenko , Andrea Santangelo , Valery Suleimanov , Sergey Tsygankov

Timing analysis of 2S 1417-624 observed with NICER and Insight-HXMT

We present a study of timing properties of the accreting pulsar 2S 1417-624 observed during its 2018 outburst, based on Swift/BAT, Fermi/GBM, Insight-HXMT and NICER observations. We report a dramatic change of the pulse profiles with…

High Energy Astrophysical Phenomena · Physics 2019-11-06 L. Ji , V. Doroshenko , A. Santangelo , C. Gungor , S. Zhang , L. Ducci , S. -N. Zhang , M. -Y. Ge , L. J. Qu , Y. P. Chen , Q. C. Bu , X. L. Cao , Z. Chang , G. Chen , L. Chen , T. X. Chen , Y. Chen , Y. B. Chen , W. Cui , W. W. Cui , J. K. Deng , Y. W. Dong , Y. Y. Du , M. X. Fu , G. H. Gao , H. Gao , M. Gao , Y. D. Gu , J. Guan , C. C. Guo , D. W. Han , W. Hu , Y. Huang , J. Huo , S. M. Jia , L. H. Jiang , W. C. Jiang , J. Jin , Y. J. Jin , L. D. Kong , B. Li , C. K. Li , G. Li , M. S. Li , T. P. Li , W. Li , X. Li , X. B. Li , X. F. Li , Y. G. Li , Z. J. Li , Z. W. Li , X. H. Liang , J. Y. Liao , C. Z. Liu , G. Q. Liu , H. W. Liu , S. Z. Liu , X. J. Liu , Y. Liu , Y. N. Liu , B. Lu , F. J. Lu , X. F. Lu , T. Luo , X. Ma , B. Meng , Y. Nang , J. Y. Nie , G. Ou , N. Sai , L. M. Song , X. Y. Song , L. Sun , Y. Tan , L. Tao , Y. L. Tuo , G. F. Wang , J. Wang , W. S. Wang , Y. S. Wang , X. Y. Wen , B. B. Wu , M. Wu , G. C. Xiao , S. L. Xiong , H. Xu , Y. P. Xu , Y. R. Yang , J. W. Yang , S. Yang , Y. J. Yang , A. M. Zhang , C. L. Zhang , C. M. Zhang , F. Zhang , H. M. Zhang , J. Zhang , Q. Zhang , T. Zhang , W. Zhang , W. C. Zhang , W. Z. Zhang , Y. Zhang , Y. Zhang , Y. F. Zhang , Y. J. Zhang , Z. Zhang , Z. L. Zhang , H. S. Zhao , J. L. Zhao , X. F. Zhao , S. J. Zheng , Y. Zhu , Y. X. Zhu , C. L. Zou

Measuring pulsar profile variations with 2-D Gaussian process regression

Time-correlated variations in the pulse profiles of radio pulsars provide insights into changes in their magnetospheres. For a small number of pulsars (~20), these variations have been shown to correlate with spin-down rate. Many of these…

High Energy Astrophysical Phenomena · Physics 2025-05-30 Michael J. Keith , Renée Spiewak , Andrew G. Lyne , Patrick Weltevrede , Danai Antonopoulou , Ben Stappers

The first continuous optical monitoring of the transitional millisecond pulsar PSR J1023+0038 with Kepler

We report on the first continuous, 80 day optical monitoring of the transitional millisecond pulsar PSR J1023+0038 carried out in mid-2017 with Kepler in the K2 configuration, when an X-ray subluminous accretion disk was present in the…

High Energy Astrophysical Phenomena · Physics 2018-07-02 A. Papitto , N. Rea , F. Coti Zelati , D. de Martino , S. Scaringi , S. Campana , E. de Oña Wilhelmi , C. Knigge , A. Serenelli , L. Stella , D. F. Torres , P. D'Avanzo , G. L. Israel

Accretion Torque Reversals in GRO J1008-57 Revealed by Insight-HXMT

GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the…

High Energy Astrophysical Phenomena · Physics 2021-02-25 W. Wang , Y. M. Tang , Y. L. Tuo , P. R. Epili , S. N. Zhang , L. M. Song , F. J. Lu , J. L. Qu , S. Zhang , M. Y. Ge , Y. Huang , B. Li , Q. C. Bu , C. Cai , X. L. Cao , Z. Chang , L. Chen , T. X. Chen , Y. B. Chen , Y. Chen , Y. P. Chen , W. W. Cui , Y. Y. Du , G. H. Gao , H. Gao , Y. D. Gu , J. Guan , C. C. Guo , D. W. Han , J. Huo , S. M. Jia , W. C. Jiang , J. Jin , L. D. Kong , C. K. Li , G. Li , T. P. Li , W. Li , X. Li , X. B. Li , X. F. Li , Z. W. Li , X. H. Liang , J. Y. Liao , B. S. Liu , C. Z. Liu , H. X. Liu , H. W. Liu , X. F. Lu , Q. Luo , T. Luo , R. C. Ma , X. Ma , B. Meng , Y. Nang , J. Y. Nie , G. Ou , X. Q. Ren , N. Sai , X. Y. Song , L. Sun , L. Tao , C. Wang , L. J. Wang , P. J. Wang , W. S. Wang , Y. S. Wang , X. Y. Wen , B. Y. Wu , B. B. Wu , M. Wu , G. C. Xiao , S. Xiao , S. L. Xiong , Y. P. Xu , R. J. Yang , S. Yang , J. J. Yang , Y. J. Yang , B. B. Yi , Q. Q. Yin , Y. You , F. Zhang , H. M. Zhang , J. Zhang , P. Zhang , W. Zhang , W. C. Zhang , Y. F. Zhang , Y. H. Zhang , H. S. Zhao , X. F. Zhao , S. J. Zheng , Y. G. Zheng , D. K. Zhou

The Critical Rotation of Strange Stars and Rapidly Rotating Pulsars

We utilize the bulk viscosity of interacting strange quark matter to reevaluate the damping time scale. The presence of medium effect of bulk viscosity leads to a stronger damping of r-modes, which can be over an order of magnitude for…

Astrophysics · Physics 2010-11-19 Zheng Xiaoping , Yang Shuhua , Li Jiarong

On the origin of super-global spin-up trends of X-ray pulsars in HMXB systems

Most X-ray pulsars in high-mass X-ray binary (HMXB) systems exhibit both global and local trends of spin acceleration (spin-up) and deceleration (spin-down). Moreover, decades-long monitored objects display even more general spin-up trends…

High Energy Astrophysical Phenomena · Physics 2025-09-23 Vitaliy Kim , Yerlan Aimuratov

Accretion torques and motion of the hot spot on the accreting millisecond pulsar XTE J1807-294

We present a coherent timing analysis of the 2003 outburst of the accreting millisecond pulsar XTE J1807-294. We find an upper limit for the spin frequency derivative of 5E-14 Hz/s. The sinusoidal fractional amplitudes of the pulsations are…

High Energy Astrophysical Phenomena · Physics 2014-11-18 Alessandro Patruno , Jacob M. Hartman , R. Wijnands , Deepto Chakrabarty , Michiel van der Klis

Spectral and temporal changes associated with flux enhancement in 4U 1626-67

4U 1626-67 is an accretion powered X-ray pulsar that shows remarkably stable X-ray luminosity above hours timescale and gradual intensity variation on a few years timescale. Here we report a significant increase in the X-ray intensity in…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Chetana Jain , Biswajit Paul , Anjan Dutta