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X-ray study of WR 48-6: A possible colliding wind binary: X-ray study of WR 48-6: a possible colliding...
Tej, Anandmayee; Pandey, Jeewan C.; Jadoliya, Vishal
This paper presents an investigation of the X-ray emission associated with the Wolf–Rayet star, WR 48-6, using observations from the XMM-Newton and Chandra X-ray telescopes covering two epochs separated by eleven months. The X-ray spectrum of WR 48-6 is well explained by a two-temperature plasma model, with cool and hot plasma temperatures of
X-ray polarization observations of IC 4329A with IXPE: Constraining the geometry of X-ray corona
Stalin, C. S.; Pal, Indrani; Chatterjee, Rwitika +1 more
X-ray polarimetry is a powerful tool to probe the geometry of the hot X-ray corona in active galactic nuclei (AGN). Here, we present our results on the characterization of the X-ray polarization of the radio-quiet Seyfert-type AGN IC 4329A at a redshift of
Low-luminosity observation of BeXRB source IGR J21347+
Tobrej, Mohammed; Rai, Binay; Ghising, Manoj +2 more
In this paper, we report the results of the detailed temporal and spectral studies of the BeXRB J21347
Science with the AstroSat Soft X-ray telescope: An overview
Dewangan, Gulab C.; Singh, Kulinder Pal; Bhattacharyya, Sudip +6 more
The Soft X-ray Telescope (SXT) aboard the AstroSat satellite is the first Indian X-ray telescope in space. It is a modest size X-ray telescope with a charge coupled device (CCD) camera in the focal plane, which provides X-ray images in the
AstroSat view of the NLS1 galaxy Mrk 335
Dewangan, Gulab C.; Misra, Ranjeev; Ezhikode, Savithri H.
We present the results from the multi-wavelength monitoring observations of the Narrow-Line Seyfert 1 galaxy Mrk 335 with AstroSat. We analysed both the X-ray (SXT and LAXPC) and UV (UVIT) data of the source at two epochs, separated by
The Radio and X-ray Mode-Switching Pulsar PSR B0943+10
Mereghetti, Sandro; Rigoselli, Michela
Observations obtained in the last years challenged the widespread notion that rotation-powered neutron stars are steady X-ray emitters. Besides a few allegedly rotation-powered neutron stars that showed 'magnetar-like' variability, a particularly interesting case is that of PSR B0943+10. Recent observations have shown that this pulsar, well studie…
Measures of the Soft X-ray Excess as an Eigenvector 1 Parameter for Active Galactic Nuclei
Marziani, P.; Perea, J.; del Olmo, A. +2 more
We present a preliminary analysis of X-ray data of quasars in the context of the 4D eigenvector 1 parameter space (Sulentic et al. 2000a, b). 4DE1 serves as a surrogate H-R diagram for representing empirical diversity among quasars and identifying the physical drivers of the diversity. The soft X-ray spectral index (Γsoft) was adopted a…
Quasi Periodic Oscillations in Blazars
Gupta, Alok C.
Here we report our recent discoveries of Quasi-Periodic Oscillations (QPOs) in blazars time series data in X-ray and optical electromagnetic bands. Any such detection can give important clue of the location and nature of the processes of emission mechanism. In the case of radio-quiet AGN, the detected QPOs are very likely to be associated with the…
X-ray Flares Observed from Six Young Stars Located in the Region of Star Clusters NGC 869 and IC 2602
Pandey, J. C.; Singh, K. P.; Kumar, Brijesh +2 more
We present, for the first time, an analysis of seven intense X-ray flares observed from six stars (LAV 796, LAV 1174, SHM2002 3734, 2MASS 02191082+5707324, V553 Car, V557 Car). These stars are located in the region of young open star clusters NGC 869 and IC 2602. These flares detected in the XMM-Newton data show a rapid rise (10–40 min) and a slow…
Orbital Signatures from Observed Light Curves of Blazars
Mangalam, A.; Mohan, P.
Variability in active galactic nuclei is observed in UV to X-ray emission based light curves. This could be attributed to orbital signatures of the plasma that constitutes the accretion flow on the putative disk or in the developing jet close to the inner region of the central black hole. We discuss some theoretical models based on this view. Thes…