Related papers: X-Ray Polarization from the Gamma-Ray Binary LS I …
LS I +61 303 and LS 5039 are two of only a handful of known high mass X-ray binaries (HMXBs) that exhibit very high energy emission in the MeV-TeV range, and these "gamma-ray binaries" are of renewed interest due to the recent launch of the…
Gamma-ray binaries are systems composed of a massive star and a compact object that produce emission from radio to very high energy gamma-rays. LS I +61 303 is one of the only six gamma-ray binaries discovered so far. It is thought that…
We report the first statistically significant detection of X-ray polarization from the high-mass X-ray binary (HMXB) 4U 1700-377, observed using the Imaging X-ray Polarimetry Explorer (IXPE). A polarization degree exceeding 10% was detected…
Radiation from X-ray pulsars (XRPs) was expected to be strongly linearly polarized owing to a large difference in their ordinary and extraordinary mode opacities. The launch of IXPE allowed us to check this prediction. IXPE observed a dozen…
Linear polarization of high-energy gamma-rays (10 MeV-100 GeV) can be detected by measuring the azimuthal angle of electron-positron pairs and observing the modulation of the azimuthal distribution. To demonstrate the gamma-ray polarization…
LS I + 61$^\circ$303 is a high-mass X-ray binary system comprising a massive Be star and a rapidly rotating neutron star. Its spectral energy distribution across multi-wavelengths categorizes it as a $\gamma$-ray binary system. In our…
We report the X-ray polarization properties of the high-synchrotron-peaked BL Lac H 1426+428, based on two-epoch observational data from the Imaging X-ray Polarimetry Explorer (IXPE). For the first observation, only an upper limit of…
We report the first detection of X-ray polarization in the horizontal branch for GX 340+0 as obtained by Imaging X-ray Polarimetry Explorer (IXPE). A polarization degree of 4.3%$\pm$0.3% is obtained. This value is in agreement with the…
We present the first X-ray polarimetric observation of the extreme high-synchrotron-peaked blazar 1ES 1101--232, conducted by the Imaging X-ray Polarimetry Explorer (IXPE). The data analysis incorporates simultaneous and quasi-simultaneous…
We report on a three year spectroscopic monitoring program of the H-alpha emission in the massive X-ray binary LS I +65 010 = 2S 0114+650, which consists of a B-supergiant and a slowly rotating X-ray pulsar. We present revised orbital…
Polarimetric measurements, especially if extended at high energy, are expected to provide important insights into the mechanisms underlying the acceleration of relativistic particles in jets. In a previous work we have shown that the…
We investigated the multiband emission from the pulsar binaries XSS J12270-4859, PSR J2039-5617, and PSR J2339-0533, which exhibit orbital modulation in the X-ray and gamma-ray bands. We constructed the sources' broadband spectral energy…
Recently, the $\gamma$-ray emission at MeV and GeV energies from the object LMC P3 in the Large Magellanic Cloud has been discovered to be modulated with a 10.3-days period, making it the first extra-galactic $\gamma$-ray binary. This work…
The spectral energy distribution from the X-ray to the very high energy regime ($>100$ GeV) has been investigated for the $\gamma$-ray binary system PSR B1259-63/SS2883 as a function of orbital phase within the framework of a simple model…
We report the first detection of X-ray polarization with the Imaging X-ray Polarimetry Explorer from the X-ray pulsar (XRP) 4U 1954$+$319. The source belongs to an extremely rare class of systems in which a slowly rotating neutron star…
We report on orbital modulation of the 100-600 MeV gamma-ray emission of the $P_{\rm B}=4.6$ hr millisecond pulsar binary PSR J2339$-$0533 using 11 yr of Fermi Large Area Telescope data. The modulation has high significance (chance…
Three binaries are now established sources of emission at very high energies (>1e11 eV). They are composed of a massive star and a compact object. The emission can be due to the interaction of the relativistic wind from a young ms pulsar…
Gamma-ray binaries have been uncovered as a new class of Galactic objects in the very high energy sky (> 100 GeV). The three systems known today have hard X-ray spectra (photon index ~ 1.5), extended radio emission and a high luminosity in…
In this paper, we performed a spectro-polarimetric analysis of the transient NS-LMXB XTE J1701-462 using IXPE, NICER, and NuSTAR data during its 2022 outburst. We report the significant detection of energy-dependent polarization in the…
We propose that the polarization of the emission from the X-ray binary Cygnus X-1, measured using the Imaging X-ray Polarimetry Explorer (IXPE), is imprinted by bulk Comptonization of coronal emission in a mildly relativistic wind or jet…