226 citations · 2.4k across the 77 of their papers we have counts for
82 papers
Magnetospheric birefringence breaks the rotating-vector model and depolarises X-ray pulsars
Alexander A. Mushtukov, Sergey S. Tsygankov, Silvia Zane +4
Accreting X-ray pulsars have long been expected to show large linear polarisation below the cyclotron resonance. In the standard picture, this follows from two facts: radiative opa…
Spin-disc misalignment drives periodic accretion and pulse profile asymmetry in X-ray pulsars
A. A. Mushtukov, V. Ganesh, S. S. Tsygankov +2
We investigate magnetospheric accretion in disc-fed X-ray pulsars assuming that the neutron star spin axis is not perpendicular to the disc plane. We focus on X-ray pulsars, where…
EXPO: a quantum leap in fast, wide-band X-ray polarimetry for astrophysics
Paolo Soffitta, Sebastien Guillot, Ian Hutchinson +137
The Enhanced X-ray Polarimetry Observatory (EXPO) is a mission concept proposed to ESA as an M8 candidate, with a prospective launch in 2041. Building on the scientific success of…
Modeling the Gravitational Wave Signal from the X-ray Pulsar Her X-1
I. D. Markozov, G. K. Pimenov, A. A. Mushtukov
The paper is devoted to modeling the gravitational waves from the X-ray pulsar Her X-1. The neutron star is considered as a freely precessing ellipsoid. The gravitational wave sign…
Real-time observations of the transition to the quiescent state in an accreting magnetised neutron star: No propeller required?
Sergey S. Tsygankov, Galina Lipunova, Valery F. Suleimanov +6
The final stages of outbursts in transient X-ray pulsars (XRPs), which are characterised by a significant decline in the mass accretion rate, provide valuable insight into the phys…
Magnetospheric flows in X-ray pulsars II: Heating, cooling and ionization degree at sub-critical accretion
Alexander A. Mushtukov, Alexander Y. Potekhin, Valery F. Suleimanov +2
Magnetospheric accretion flows in X-ray pulsars shape their spectra, polarization, and variability. We model the thermal balance of the flow enveloping the neutron star magnetosphe…
Detection and luminosity-dependent evolution of the high-energy hump in the Be/X-ray pulsar 1A 1118-61
Alexander Salganik, Sergey S. Tsygankov, Sergey V. Molkov +12
Context. Accreting X-ray pulsars exhibit strong luminosity-dependent changes in their broad-band spectra. At high luminosities, their spectra are usually described by a power-law c…
Rapid quasi-periodic reconfiguration of the accretion column in pulsar 1A 0535+262
Lingda Kong, Xiaohang Dai, Andrea Santangelo +12
Accretion onto strongly magnetized neutron stars is commonly interpreted using quasi-steady models, in which the accretion-column structure adjusts smoothly to the mass inflow rate…
Vacuum polarization and cyclotron resonance effects on radiative transfer and plasma deceleration in subcritical X-ray pulsars
I. D. Markozov, A. Y. Potekhin, A. D. Kaminker +1
We investigate the spectrum and polarization of radiation emerging from a subcritical X-ray pulsar using self-consistent radiation-hydrodynamic simulations of an accretion channel…
Beaming of polarized radiation in subcritical X-ray pulsars
I. D. Markozov, A. Y. Potekhin, A. D. Kaminker +1
Radiation of X-ray pulsars is powered by accretion on the neutron star surface from a binary companion under the influence of a strong magnetic field. We study beaming of this radi…
Discovery of energy-dependent phase variations in the polarization angle of Cen X-3
Qing-Chang Zhao, Lian Tao, Sergey S. Tsygankov +7
We present a detailed polarimetric analysis of Cen X-3 using \ixpe observations during its high state, revealing complex energy-dependent polarization behavior. While phase-average…
Propeller effect in action: Unveiling quenched accretion in the transient X-ray pulsar 4U 0115+63
Hua Xiao, Sergey S. Tsygankov, Valery F. Suleimanov +3
The Be/X-ray pulsar 4U 0115+63 underwent a type II outburst in 2023. After the outburst, similar to the outbursts in 2015 and 2017, the source decayed into a quiescent state. Two o…
Angle-dependent hardening of the reprocessed spectra in ULXs powered by accretion onto neutron stars
Sricheta Karmakar, Alexander A. Mushtukov, Matthew Middleton
It is anticipated that mass accretion rates exceeding approximately in X-ray pulsars lead to radiation-driven outflows from super-critical accretion disc…
Gamma-ray lines, electron-positron annihilation, and possible radio emission in X-ray pulsars
Alexander A. Mushtukov, Emir Tataroglu, Alex J. Cooper +1
Accretion onto neutron stars (NSs) in X-ray pulsars (XRPs) results in intense X-ray emission, and under specific conditions, high-energy nuclear interactions that produce gamma-ray…
Probing the emission geometry of the X-ray pulsar 2S 1417624 during a weak outburst with NICER, IXPE, and NuSTAR
Menglei Zhou, Pengju Wang, Honghui Liu +12
We report results from a multi-mission observational campaign of the transient X-ray pulsar 2S~1417624 during its 2025 outburst, using data from NICER, IXPE, and NuSTAR. Phase-a…
Probing the polarized emission from the accretion-powered pulsar 4U 1907+09 with IXPE
Menglei Zhou, Lorenzo Ducci, Honghui Liu +12
We present observations of the accretion-powered X-ray pulsar (XRP) 4U 1907+09, conducted with the Imaging X-ray Polarimetry Explorer (IXPE) that delivers the first high-quality po…
Discovery of a 0.8-mHz quasi-periodic oscillation in the transient X-ray pulsar SXP31.0 and associated timing transitions
Alexander Salganik, Sergey S. Tsygankov, Sergey V. Molkov +5
We present the first broadband spectral and timing study of the Be/X-ray pulsar XTE J0111.27317 (SXP31.0) during the first major outburst since its discovery in 1998. This giant…
Physics of Strong Magnetism with eXTP
Mingyu Ge, Long Ji, Roberto Taverna +47
In this paper we present the science potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission, in its new configuration, for studies of strongly magnetized compact obj…
Exploring polarization and geometry in the X-ray pulsar 4U 1538-52
Vladislav Loktev, Sofia V. Forsblom, Sergey S. Tsygankov +12
The Imaging X-ray Polarimetry Explorer (IXPE) observations of accreting X-ray pulsars (XRPs) continue to provide novel insights into the physics and geometry of these sources. We p…
Revealing two orthogonally polarized spectral components in Vela X-1 with IXPE
Sofia V. Forsblom, Sergey S. Tsygankov, Valery F. Suleimanov +2
Polarimetric observations of X-ray pulsars (XRPs) have provided us with the key to unlocking their geometrical properties. Thanks to the Imaging X-ray Polarimetry Explorer (IXPE) t…
Continuous evolution of the polarization properties in the transient X-ray pulsar RX J0440.9+4431/LS V +44 17
Q. C. Zhao, L. Tao, S. Sergey Tsygankov +6
We present a detailed time-resolved and phase-resolved polarimetric analysis of the transient X-ray pulsar RX J0440.9+4431/LS V +44 17, using data from the Imaging X-ray Polarimetr…
Searching for redshifted 2.2 MeV neutron-capture lines from accreting neutron stars: Theoretical X-ray luminosity requirements and INTEGRAL/SPI observations
L. Ducci, A. Santangelo, S. Tsygankov +2
Accreting neutron stars (NSs) are expected to emit a redshifted 2.2 MeV line due to the capture of neutrons produced through the spallation processes of He and heavier ions in…
Neutrino beaming in ultraluminous X-ray pulsars as a result of gravitational lensing by neutron stars
Alexander A. Mushtukov, Alexander Y. Potekhin, Ivan D. Markozov +6
X-ray pulsars experiencing extreme mass accretion rates can produce neutrino emission in the MeV energy band. Neutrinos in these systems are emitted in close proximity to the stell…
Probing the polarized emission from SMC X-1: the brightest X-ray pulsar observed by IXPE
Sofia V. Forsblom, Sergey S. Tsygankov, Juri Poutanen +101
Recent observations of X-ray pulsars (XRPs) performed by the Imaging X-ray Polarimetry Explorer (IXPE) have made it possible to investigate the intricate details of these objects i…