Related papers: The binary millisecond pulsar PSR J1023+0038 durin…

PSR J1744-3922 is a binary pulsar exhibiting highly variable pulsed radio emission. We report on a statistical multi-frequency study of the pulsed radio flux variability which suggests that this phenomenon is extrinsic to the pulsar and…

We present the first optical circular and linear polarization measurements of two polar candidates from ROSAT: 1RXS J161008.0+035222 and 1RXS J231603.9-052713. We also present H band near-infrared photometry of the last object. The presence…

The source IGR J17200-3116 was discovered in the hard X-ray band by INTEGRAL. A periodic X-ray modulation at ~326 s was detected in its Swift light curves by our group (and subsequently confirmed by a Swift campaign). In this paper, we…

We report the first detection of an optical millisecond pulsar with the fast photon counter Aqueye+ in Asiago. This is an independent confirmation of the detection of millisecond pulsations from PSR J1023+0038 obtained with SiFAP at the…

We present a study of the quiescent optical counterpart of the Accreting Millisecond X-ray Pulsar XTE J1814-338, carrying out multiband (BVR) orbital phase-resolved photometry using the ESO VLT/FORS2. The optical light curves are consistent…

IGR J17511-3057 is the second X-ray transient accreting millisecond pulsar discovered by INTEGRAL. It was in outburst for about a month from September 13, 2009. The broad-band average spectrum is well described by thermal Comptonization…

SAX J0635.2+0533 is a binary pulsar with a very short pulsation period ($P$ = 33.8 ms) and a high long-term spin down ($\dot P$ $>$ 3.8$\times10^{-13}$ s s$^{-1}$), which suggests a rotation-powered (instead of an accretion-powered) nature…

Weakly magnetic, millisecond spinning neutron stars attain their very fast rotation through a 1E8-1E9 yr long phase during which they undergo disk-accretion of matter from a low mass companion star. They can be detected as accretion-powered…

CXOU J110926.4-650224 is a candidate transitional millisecond pulsar (tMSP) with X-ray and radio emission properties reminiscent of those observed in confirmed tMSPs in their X-ray 'subluminous' disc state. We present the results of…

The accretion-powered millisecond X-ray pulsar, SAX J1808.4-3658, was observed in quiescence with ASCA in September 1999. We detected a dim X-ray source in the SIS data at the position consistent to SAX J1808.4-3658. The source count rate…

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…

The optical counterpart of the transient, millisecond X-ray pulsar SAX J1808.4-3658 was observed in four colours (BVRI) for five weeks during the 2005 June-July outburst. The optical fluxes declined by ~2 magnitudes during the first 16 days…

We report on the discovery and analysis of an X-ray pulsar, AX J0058-7203, in the Small Magellanic Cloud. This pulsar exhibits coherent pulsations at P= 280.3 s with a double-peak structure. The X-ray spectrum is well fitted with a simple…

We present the timing and spectral properties of the transient Be/X-ray binary pulsar 3A 0535+262 during quiescence using three observations with the narrow field imaging instruments (NFI) of BeppoSAX. Assuming a distance of 2 kpc for this…

We present X-ray, ultraviolet, and optical observations of 1RXS J154439.4-112820, the most probable counterpart of the unassociated Fermi LAT source 3FGL J1544.6-1125. The optical data reveal rapid variability, which is a feature of…

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…

The transient Be/X-ray binary A0538-66 shows peculiar X-ray and optical variability. Despite numerous studies, the intrinsic properties underlying its anomalous behaviour remain poorly understood. Since 2014 September we are conducting the…

Simultaneous observations of the accretion-powered millisecond pulsar IGR J00291+5934 by International Gamma-Ray Astrophysics Laboratory and Rossi X-ray Timing Explorer during the 2004 December outburst are analysed. The average spectrum is…

We report on the discovery of the new accreting millisecond X-ray pulsar SRGAJ144459.2-604207 using the SRG/ART-XC data. The source was observed twice in February 2024 during the declining phase of the outburst. Timing analysis revealed a…

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…