We have carried out the first spectro-polarimetric study of the bright NS-LMXB GX 9+9 using IXPE and AstroSat observations. We report a significant detection of polarization of $1.7\pm 0.4~{{\%}}$ over the 2 − 8 keV energy band, with a polarization angle of 63○ ± 7○. The polarization is found to be energy-dependent, with a 3σ polarization degree consistent with null polarization in 2 − 4 keV, and 3.2% in 4 − 8 keV. Typical of the spectra seen in NS-LMXBs, we find that a combination of soft thermal emission from the accretion disc and Comptonized component from the optically thick corona produces a good fit to the spectra. We also attempt to infer the individual polarization of these components, and obtain a 3σ upper limit of $\sim 11~{{\%}}$ on the polarization degree of the thermal component, and constrain that of the Comptonized component to $\sim 3~{{\%}}$. We comment on the possible corona geometry of the system based on our results.

We have carried out the first spectro-polarimetric study of the bright NS-LMXB GX 9+9 using IXPE and AstroSat observations. We report a significant detection of polarization of 1.7 ± 0.4% over the 2 − 8 keV energy band, with a polarization angle of 63 • ± 7 • . The polarization is found to be energy-dependent, with a 3σ polarization degree consistent with null polarization in 2 − 4 keV, and 3.2% in 4 − 8 keV. Typical of the spectra seen in NS-LMXBs, we find that a combination of soft thermal emission from the accretion disc and Comptonized component from the optically thick corona produces a good fit to the spectra. We also attempt to infer the individual polarization of these components, and obtain a 3σ upper limit of ∼ 11% on the polarization degree of the thermal component, and constrain that of the Comptonized component to ∼ 3%. We comment on the possible corona geometry of the system based on our results.

We present an in-depth analysis and results of eleven XMM-Newton datasets, spanning 2000 to 2016, of the anomalous X-ray Pulsar CXOU J010043.1−721134 which has been classified as a magnetar. We find a spin-period of 8.0275(1) s as of December 2016 and calculate the period derivative to be (1.76 ± 0.02) × 10−11 s s−1, which translate to a dipolar magnetic field strength of 3.8 × 1014 G and characteristic age of ∼7200 yr for the magnetar. It has a double-peaked pulse profile, with one broad and one narrow peak, in both soft (0.3 − 1.3 keV) and hard (1.3 − 8 keV) energy bands. The pulse fractions in the two energy bands are found to be consistent with constant values. These results are in agreement with previously published results for this source. Although two-component models produce acceptable fits to its energy spectra, single component models are much simpler and are able to explain the similarity of the pulse profiles in the low and high energy bands. We attempt fitting with four different single-component models and find that the best fit to the spectra is obtained by fitting a thermal Comptonization model with the photon index (Γ) between 2.0 − 2.7 and the electron temperature (kTe) between 0.5 − 0.9 keV, for a seed blackbody photon distribution of 0.2 keV. Finally, we conclude by discussing our results briefly.