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An accreting pulsar with extreme properties drives an ultraluminous x-ray source in NGC 5907
Observations showing that NGC 5907 ULX is instead an x-ray accreting neutron star (NS) with a spin period evolving from 1.43 seconds in 2003 to 1.13 seconds in 2014 suggest that other extreme ULXs (x-ray luminosity ≥ 1041 erg second−1) might harbor NSs.
Discovery of a 0.42-s pulsar in the ultraluminous X-ray source NGC 7793 P13
NGC 7793 P13 is a variable (luminosity range ∼100) ultraluminous X-ray source proposed to host a stellar-mass black hole of less than 15 M⊙ in a binary system with orbital period of 64 d and a 18-23
Swings between rotation and accretion power in a binary millisecond pulsar
Observations of accretion-powered, millisecond X-ray pulsations from a neutron star previously seen as a rotation- powered radio pulsar show the evolutionary link between accretion and rotation-powered millisecond pulsars, but also that some systems can swing between the two states on very short timescales.
Magnetic-driven Orbital Evolution of an Accreting Millisecond Pulsar: Witnessing the Banquet of a Hidden Black Widow
We report here on the orbital evolution of the accreting millisecond pulsar SAX J1808.4{3658. In particular, we nd for this source the rst estimate of the orbital period derivative in an accreting
A strongly magnetized pulsar within the grasp of the milky way’s supermassive black hole
We acknowledge support by grants AYA 2012-39303, SGR2009-811, iLINK 2011-0303, AYA 2010-21097-C03-02, Prometeo 2009/103, AYA2010-17631, P08-TIC-4075, INAF 2010 PRIN grant, Chandra Awards GO2-13076X,
Order in the Chaos: Spin-up and Spin-down during the 2002 Outburst of SAX J1808.4–3658
We present a timing analysis of the 2002 outburst of the accreting millisecond pulsar SAX J1808.4-3658. A study of the phase delays of the entire pulse profile shows a behavior that is surprising and
N.R. is supported by a Ramon y Cajal Research Fellowship, and by grants AYA2009-07391, AYA2012-39303, SGR2009-811, TW2010005, and iLINK 2011-0303. J.A.P. and D.V. acknowledge support from the grants
The spin and orbit of the newly discovered pulsar IGR J17480-2446
We present an analysis of the spin and orbital properties of the newly discovered accreting pulsar IGR J17480-2446, located in the globular cluster Terzan 5. Considering the pulses detected by the
New ephemeris of the ADC source 2A 1822-371: a stable orbital-period derivative over 30 years
We report on a timing of the eclipse arrival times of the low mass X-ray binary and X-ray pulsar 2A 1822-371 performed using all available observations of the Proportional Counter Array on board the
X-ray coherent pulsations during a sub-luminous accretion disc state of the transitional millisecond pulsar XSS J12270−4859
We present the first detection of X-ray coherent pulsations from the transitional millisecond pulsar XSS J12270-4859, while it was in a sub-luminous accretion disk state characterized by a 0.5-10 keV