Related papers: The high optical polarization in the Be/X-ray bina…
We present a type-I outburst of the high-mass X-ray binary EXO 2030+375, detected during INTEGRAL's Performance and Verification Phase in December 2002 (on-source time about 10e+06 seconds). In addition, six more outbursts have been…
Since the opacity of a magnetized plasma depends on polarization of radiation, the radiation emergent from atmospheres of neutron stars with strong magnetic fields is expected to be strongly polarized. The degree of linear polarization,…
We present Halpha linear spectropolarimetry of a large sample of Herbig Ae/Be stars. Together with newly obtained data for 17 objects, the sample contains 56 objects, the largest such sample to date. A change in linear polarization across…
We report the first measurement of the zodiacal light (ZL) polarization spectrum in the near-infrared between 0.8 and 1.8 $\mu$m. Using the low-resolution spectrometer (LRS) on board the Cosmic Infrared Background Experiment (CIBER),…
The Be X-ray binary pulsar EXO 2030+375, first detected in 1985, has shown a significant detected X-ray outburst at nearly every periastron passage of its 46-day orbit for the past ~25 years, with one low state accompanied by a torque…
We report the discovery of circularly polarised radio emission from the radio-jet X-ray binary SS 433 with the Australia Telescope Compact Array. The flux density spectrum of the circular polarization, clearly detected at four frequencies…
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$0.3% is obtained. This value is in agreement with the…
We report results of a theoretical investigation of polarization of the X-ray emissions induced in charge-exchange collisions of fully stripped solar wind ions C$^{6+}$ and O$^{8+}$ with the heliospheric hydrogen atoms. The polarization of…
Be X-ray binaries (BeXRBs) may show strong X-ray and optical variability, and can exhibit some of the brightest outbursts that break through the Eddington limit. Major X-ray outbursts are often accompanied by strong optical flares that…
We calculate the degree of linear polarization of radiation from stars having planets that may not be resolved spatially. We assume single scattering by water and silicate particulates in the planetary atmosphere. The dilution of the…
We present the discovery of X-ray polarization from the neutron star low-mass X-ray binary and Z-source, GX~340$+$0, using an Imaging X-ray Polarimetry Explorer (IXPE) observation in March 2024. Along with the IXPE observation, we conducted…
We report the detection of phase-locked polarization in the bright ($m_V$=2.98-3.24) semidetached eclipsing binary $\mu^1$ Sco (HD 151890). The phenomenon was observed in multiple photometric bands using two different HIPPI-class (HIgh…
We report the X-ray polarization properties of the high-synchrotron-peaked (HSP) blazar PKS 2155$-$304 based on observations with the Imaging X-ray Polarimetry Explorer (IXPE). We observed the source between Oct 27 and Nov 7, 2023. We also…
The origin of nebular HeII emission, which is frequently observed in low-metallicity (O/H) star-forming galaxies, remains largely an unsolved question. Using the observed anticorrelation of the integrated X-ray luminosity per unit of star…
Polarization detection of X-rays is a non-negligible topic to astrophysical observation. Many polarization detection methods have been well developed for X-rays in the energy range below 10~keV, while the detection at 10-30~keV is rarely…
An $R$--band photopolarimetric variability analysis of the TeV bright blazar W Comae, between 2008 February 28 and 2013 May 17, is presented. The source showed a gradual tendency to decrease its mean flux level with a total change of…
The X-ray polarization observations made possible with the Imaging X-ray Polarimetry Explorer (IXPE) offer new ways of probing high-energy emission processes in astrophysical jets from blazars. Here we report on the first X-ray polarization…
In the last 10 years, since its last giant outburst in 2006, regular X-ray outbursts (type I) were detected every periastron passage in the Be X-ray binary EXO 2030+375. Recently, however, it was reported that the source started to show a…
I discuss the X-ray observations of Be stars, and how their properties compare to non-emission B stars. I focus on several specific stars that show high flux levels and variability but also report on several interesting survey results. The…
We present near-simultaneous X-ray and optical polarization measurements in the high synchrotron peaked (HSP) blazar Mrk 421. The X-ray polarimetric observations were carried out using {\it Imaging X-ray Polarimetry Explorer} ({\it IXPE})…