Related papers: A low luminosity state in the massive X-ray binary…

The PSR J1023+0038 binary system hosts a neutron star and a low-mass, main-sequence-like star. It switches on year timescales between states as an eclipsing radio millisecond pulsar and a low-mass X-ray binary. We present a multi-wavelength…

PSR J1023+0038 (J1023) is a binary system hosting a neutron star and a low mass companion. J1023 is the best studied transitional pulsar, alternating a faint eclipsing millisecond radio pulsar state to a brighter X-ray active state. At…

We continue to study the fast X-ray transient XTE J1901+014 discovered in 2002 by the RXTE observatory, whose nature has not yet been established. Based on the XMM-Newton observations of the source in 2006, we have obtained its energy…

We report on the XMM-Newton observation of the HMXRB X Persei, the prototype of the persistent and low-luminosity Be/neutron star pulsars, which was performed on February 2003. The source was detected at a luminosity level of ~ 1.4x10^35…

ASCA observed the central region of the Small Magellanic Cloud, and found a hard X-ray source, AX J0051-733, at the position of the ROSAT source RX J0050.8-7316, which has an optical counterpart of a Be star. Coherent X-ray pulsations of…

We report on the deep observations of the "bursting pulsar" GRO J1744-28, which were performed with XMM-Newton and aimed to clarify the origin of its X-ray emission in quiescence. We detect the source at a luminosity level of $\sim10^{34}$…

The pulsar PSR J0631+1036 was discovered during a radio search of Einstein X-ray source error circles. A detection of a 288ms sinusoidal modulation in the ASCA lightcurve, the same period as the radio pulsar, appeared to confirm the…

Context. In 1998 the first accreting millisecond pulsar, SAX J1808.4-3658, was discovered and to date 18 systems showing coherent, high frequency (> 100 Hz) pulsations in low mass X-ray binaries are known. Since their discovery, this class…

The neutron star binary SAX J1747.0-2853, located in the Galactic Center region at about 0.5 deg from Sgr A* and at a distance of 9 kpc, has been observed in outburst four times (1998, 1999, 2000 and 2001) by BeppoSAX and RossiXTE. At the…

We present the results obtained from timing and spectral studies of Be/X-ray binary pulsar EXO 2030+375 using observations with the Large Area Xenon Proportional Counters and Soft X-ray Telescope of AstroSat, at various phases of its Type-I…

We present preliminary results of observations of X-ray pulsar SAX J2103.5+4545 with INTEGRAL observatory in Dec 2002. Maps of this sky region in energy bands 3-10, 15-40, 40-100 and 100-200 keV are presented. The source is significantly…

We report on a 20 ks BeppoSAX observation of the transient 2.5 ms X-ray pulsar SAX J1808.4-3658 in its quiescent state. A source at a level of ~ 3 x 10^-3 c/s was detected with the BeppoSAX/MECS at a position consistent with that of SAX…

We report the discovery with XMM-Newton of 3-s X-ray pulsations from 3XMM J004232.1+411314, a dipping source that dominates the hard X-ray emission of M31. This finding unambiguously assesses the neutron star (NS) nature of the compact…

We investigated the optical, X-ray, and gamma-ray variability of the pulsar SAX J2103.5+4545. Our timing and spectral analyses of the X-ray and gamma-ray emissions from the source using RXTE and INTEGRAL data show that the shape of its…

We observed RX J0520.5-6932 in the X-rays and studied the optical light curve of its counterpart to verify it as a Be/X-ray binary. We performed an XMM-Newton anticipated target of opportunity observation in January 2013 during an X-ray…

We report on observations of the unusual neutron-star binary system FIRST J102347.6+003841 carried out using the XMM-Newton satellite. This system consists of a radio millisecond pulsar in an 0.198-day orbit with a ~0.2 solar-mass…

During a search for coherent signals in the X-ray archival data of XMM-Newton, we discovered a modulation at 1.2 s in 3XMM J004301.4+413017 (3X J0043), a source lying in the direction of an external arm of M 31. This short period indicates…

The results of the broadband spectral and timing study of the recently discovered transient X-ray pulsar MAXI J0903-531 in a wide range of luminosities differing by a factor of ~30 are reported. The observed X-ray spectrum in both states…

We study the recently discovered Be/X-ray pulsar MAXI J0655--013 using the 2022 \emph{NuSTAR} observations. The paper is the first detailed study of the timing and spectral properties of the source. The pulse profiles of the pulsar vary…

We observed the newly discovered X-ray source Swift J053041.9-665426 in the X-ray and optical regime to confirm its proposed nature as a high mass X-ray binary. We obtained XMM-Newton and Swift X-ray data, along with optical observations…