Related papers: Why does the intermediate polar V405 Aurigae show …
Using observations of X-ray pulsar Her X-1 by the Imaging X-ray Polarimetry Explorer, we report on a highly significant ($>17\sigma$) detection of the polarization signal from an accreting neutron star. The observed degree of the linear…
We have undertaken an extensive study of X-ray data from the accreting millisecond pulsar XTE J1751-305 observed by RXTE and XMM-Newton during its 2002 outburst. In all aspects this source is similar to a prototypical millisecond pulsar SAX…
From optical photometry the cataclysmic variable RX J0944.5+0357 is shown to have a double-peaked pulse profile with a period of ~2160 s. The two peaks vary rapidly in relative amplitude. Often most of the optical power is concentrated in…
XY Ari is one of the few known eclipsing intermediate polars. We present results from a detailed analysis of an unpublished archival observation using XMM-Newton EPIC pn and MOS data in a quiescent state of XY Ari. The X-ray orbital…
We report the results of ALMA observations of a protoplanetary disk surrounding the Herbig Ae star AB Aurigae. We obtained high-resolution (0.1"; 14 au) images in $^{12}$CO (J=2-1) emission and in dust continuum at the wavelength of 1.3 mm.…
We present low and intermediate resolution spectroscopy of the optical counterpart to the recently discovered pulsating X-ray source 1WGA J1958.2+3232. The presence of strong HI, HeI and HeII emission lines together with the absence of…
We present a detailed study of the X-ray emission from PSR B1055-52 using XMM-Newton observations from 2019 and 2000. The phase-integrated X-ray emission from this pulsar is poorly described by existing neutron star atmosphere models.…
We have derived new orbits for zeta Aur, 32 Cyg, and 31 Cyg with observations from the TSU Automatic Spectroscopic Telescope and used them to identify non-orbital velocities of the cool supergiant components of these systems. We measure…
We have carried out observations of the X-ray transient GX339-4 during its high-soft and low-hard X-ray spectral states. Our high-resolution spectroscopic observation in 1999 April suggests that the H-alpha line has a single-peaked profile…
In `spider' pulsars, the X-ray band is dominated by Intrabinary Shock (IBS) synchrotron emission. While the double-peaked X-ray light curves from these shocks have been well characterized in several spider systems (both black widows and…
The quiescent emission of the anomalous X-ray pulsar (AXP) 4U 0142+61 extends over a broad range of energy, from radio up to hard X-rays. In particular, this object is unique among soft gamma-ray repeaters (SGRs) and AXPs in presenting…
The Be/X-ray binary A 0535+26 showed a normal (type I) outburst in August 2009. It is the fourth in a series of normal outbursts associated with the periastron, but is unusual by presenting a double-peaked light curve. The two peaks reached…
Accretion-powered X-ray pulsars 4U 1626-67, GX 1+4, and OAO 1657-415 have recently shown puzzling torque reversals. These reversals are characterized by short time scales, on the order of days, nearly identical spin-up and spin-down rates,…
Millisecond spinning, low magnetic field neutron stars are believed to attain their fast rotation in a 0.1-1 Gyr-long phase during which they accrete matter endowed with angular momentum from a low-mass companion star. Despite extensive…
We present Suzaku XIS observation of V2491 Cyg (Nova Cyg 2008 No. 2) obtained in quiescence, more than two years after the outburst. The nova was detected as a very luminous source in a wide spectral range from soft to hard X-rays. A very…
Three high-mass X-ray binaries have been discovered recently exhibiting enormous spinup rates. Conventional accretion theory predicts extremely high surface dipolar magnetic fields that we believe are unphysical. Instead, we propose quite…
Pulse timing of the isolated pulsar PSR B1882-11 shows strong Fourier power at periods ~1000, 500 and 250 d, correlated with changes in the pulse profile (Stairs, Lyne & Shemar 2000). We study the extent to which these data can be explained…
We show that the soft X-ray spectra and light curves observed with the ROSAT and EUVE from the closest known millisecond pulsar J0437--4715 can be interpreted as thermal radiation from two hot polar caps whose emitting layers (atmospheres)…
The recent observations of the anomalous X-ray pulsars 4U 0142+61 and 1RXS J170849.0-400910 by the Imaging X-ray Polarimetry Explorer (IXPE) opened up a new avenue to study magnetars, neutron stars endowed with superstrong magnetic fields…
We analyze high-contrast, medium-spectral-resolution $H_{\rm \alpha}$ observations of the star AB Aurigae using the Very Large Telescope's Multi Unit Spectroscopic Explorer (MUSE). In multiple epochs, MUSE detects the AB Aur b protoplanet…