相关论文: Study on the magnetic field strength of NGC 300 UL…
The accreting millisecond pulsar SAX J1808.4-3658 has shown a peculiar orbital evolution in the past with an orbital expansion much faster than expected from standard binary evolutionary scenarios. Previous limits on the pulsar spin…
We report observations of SMC X-1 in three new high-intensity states with ROSAT HRI in December 1995, May 1997, and March 1998 in which pulsations with a period of 0.70769+/-0.00006 sec, 0.70706+/-0.00001 sec, and 0.706707+/-0.00001 sec…
Accreting X-ray pulsars (XRPs) are presumably ideal targets for polarization measurements, as their high magnetic field strength is expected to polarize the emission up to a polarization degree of ~80%. However, such expectations are being…
Using X-ray data from the Rossi X-Ray Timing Explorer (RXTE), we report the pulse timing results of the accretion powered high mass X-ray binary (HMXRB) pulsar 4U 1907+09 covering a time span of almost two years. We measured three new pulse…
The recent discovery of a radio-emitting neutron star with an ultralong spin period of 76 s, PSR J0901-4046, raises a fundamental question on how such a slowly rotating magnetized object can be active in the radio band. A canonical magnetic…
We present a timing analysis of the 2015 outburst of the accreting millisecond X-ray pulsar SAX J1808.4-3658, using non-simultaneous XMM-Newton and NuStar observations. We estimate the pulsar spin frequency and update the system orbital…
The Rossi X-ray Timing Explorer has observed five outbursts from the transient 2.5 ms accretion-powered pulsar SAX J1808.4-3658 during 1998-2008. We present a pulse timing study of the most recent outburst and compare it with the previous…
We analyze the observations of the X-ray pulsar KS 1947+300 performed by the INTEGRAL and RXTE observatories over a wide (3-100 keV) X-ray energy range. The shape of the pulse profile was found to depend on the luminosity of the source.…
We report on analysis of the poorly studied source 2RXP J130159.6-635806 at different epochs with ASCA, Beppo-SAX, XMM-Newton, and INTEGRAL. The source shows coherent X-ray pulsations at a period ~700s with an average spin up rate of about…
We present the results of the INTEGRAL monitoring campaign on the accreting low mass X-ray binary pulsar GX 1+4 performed during the Galactic plane scan of the INTEGRAL Core Programme. The source was observed in different luminosity states…
The spin behaviour of the neutron star in the newly discovered young Be/X-ray long-period pulsar SXP 1062 is discussed. The star is observed to rotate with the period of 1062s, and spin-down at the rate ~ - 2.6 \times 10^{-12} Hz s^{-1}. I…
In recent work with high-resolution grating spectrometers (RGS) aboard XMM-Newton Pinto et al. (2016) have discovered that two bright and archetypal ultraluminous X-ray sources (ULXs) have strong relativistic winds in agreement with…
Observations made using the Rossi X-ray Timing Explorer have shown that accreting weak-field neutron stars in low-mass X-ray binary systems (LMXBs) produce three distinct types of millisecond X-ray oscillations that can be used to determine…
We present observational evidence for "propeller" effects in two X-ray pulsars, GX 1+4 and GROJ1744-28. Both sources were monitored regularly by the Rossi X-ray Timing Explorer (RXTE) throughout a decaying period in the X-ray brightness.…
Despite two decades of studies, it is still not clear whether ULX spectral transitions are due to stochastic variability in the wind or variations in the accretion rate or in the source geometry. The compact object is also unknown for most…
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…
We report the detection of a 115 day periodicity in SWIFT/XRT monitoring data from the ultraluminous X-ray source (ULX) NGC 5408 X-1. Our ongoing campaign samples its X-ray flux approximately twice weekly and has now achieved a temporal…
SN2010da/NGC 300 ULX-1 was first detected as a supernova impostor in May 2010 and was recently discovered to be a pulsating ultraluminous X-ray source. In this letter, we present VLT/X-shooter spectra of this source obtained in October…
In this work we explore the possible evolutionary track of the neutron star in the newly discovered Be/X-ray binary SXP 1062, which is believed to be the first X-ray pulsar associated with a supernova remnant. Although no cyclotron feature…
We studied possible evolution of the rotational period and the magnetic field of the X-ray source RX J0720.4-3125 assuming this source to be an isolated neutron star accreting from the interstellar medium. Magnetic field of the source is…