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We present a joint spectral analysis of ROSAT PSPC, Swift XRT, and NuSTAR FPMA/B data of the nova-like (NL) cataclysmic variables (CVs), BZ Cam and V592 Cas in the 0.1-78.0 keV band. Plasma models of collisional equilibrium fail to model the 6.0-7.0 iron line complex and continuum with $\chi^2_\nu$ larger than 2.0. Our results show nonequilibrium ionization (NEI) conditions in the X-ray plasma with temperatures of 8.2-9.4 keV and 10.0-12.9 keV for BZ Cam and V592 Cas, respectively. The centroids of He-like and H-like iron ionization lines are not at their equilibrium values as expected from NEI conditions. We find power law spectral components that reveal the existence of scattering and Comptonization with a photon index of 1.50-1.87. We detect a P Cygni profile in the H-like iron line of BZ Cam translating to outflows of 4500-8700 km s$^{-1}$ consistent with the fast winds in the optical and UV. This is the first time such a fast collimated outflow is detected in the X-rays from an accreting CV. An Iron K$\alpha$ line around 6.2-6.5 keV is found revealing the existence of reflection effects in both sources. We study the broadband noise and find that the optically thick disk truncates in BZ Cam and V592 Cas consistent with transition to an advective hot flow structure. V592 Cas also exhibits a quasi-periodic oscillation at 1.4$^{+2.6}_{-0.3}$ mHz. In general, we find that the two NLs portray spectral and noise characteristics as expected from advective hot accretion flows at low radiative efficiency., Comment: 19 pages, 2 Tables, 5 Figures (13 individual); Astrophysical Journal in Press, subject to minor changes during the production process

We present for the first orbital phase resolved spectra of intermediate polar (IP), EX Hya, during two different states with a factor of 3 difference between the X‐ray count rates. We find definite spectral variations between different states of the source. The adopted model is composed of two MEKAL plus a VMCFLOW components to account for the continuum which is partially absorbed. Additional Gaussian lines at energies ∼6, 4, 6.7 and 6.9 keV were also included to fit the residuals. The soft component of the spectrum is found to be harder during orbital minimum, suggesting the presence of extra ionized absorbing column. Moreover, the presence of cold emission Fekα line points toward the presence of a reflection component probably due to an accretion disk and/or a bulge at the impact zone.

We present the frequency resolved energy spectra (FRS) of the low‐mass X‐ray binary dipper XB 1323‐619 and EXO 0748‐676 using archival XMM‐Newton observations. The FRS of XB 1323‐619 is well described by a single blackbody component with kT in a range 1.2–1.6 keV. We attribute this to an existing boundary layer, the likely source of the soft emission, supported by radiation pressure. We detect a different form of FRS for the frequency ranges 0.9–6 Hz and 8–30 Hz which is modeled best with a power law and a gaussian emission line at 6.5−0.1+0.1 keV. EXO 0748‐676 reveals different variable regions found in different states with spectral hardening as the frequency increases showing similar FRS behavior to Z‐sources. A disk blackbody emission component of 0.15 keV is found in the high state and it disappears at higher frequencies as expected. In the low state FRS (0.05–50 Hz) is independent of Fourier frequency and shows a fluorescence Fe line at 4.3–5.5 keV with large equivalent width.

I present archival data of the dipping LMXB systems, XB 1916–053, XB 1323–619, X 1624–490, and 4U 1746–371 obtained by the ISGRI and JEM‐X detectors on‐board the INTEGRAL Observatory. The spectral parameters derived from the fits to the data are consistent with hot coronal regions in these systems where the electron temperatures are in a range 4.9–18.8 keV with the exception of XB 1323‐62 having an unbounded temperature. The optical depth to Compton scattering, τ is low and consistent with electron densities ne

We present the broad‐band noise structure of Anomalous X‐Ray Pulsars (AXPs) and Soft Gamma Repeaters (SGRs) in the 2–60 keV energy band which are thought to be powered by either magnetic decay (Thompson & Duncan 1995) or accretion (Alpar 2001). We have used Rossi X‐ray Timing Explorer (R‐XTE) PCA archival light curves and derived time series for 4 AXPs and 1 SGR. We detect that AXP and SGR sources show band limited noise at low frequencies in the range 0.005–0.05 Hz. We find that this noise level can be associated with their bursts, glitches or flaring activities. We discover band‐limited red noise in 1E 2259+586 only for about two years after its outburst and the associated glitch. The system shows no broad‐band noise otherwise. The other three AXPs indicate a lower band‐limited noise level in comparison with 1E 2259+586 and it is persistent, but show variations. We favour a model where this broad‐band noise particularly as detected in 1E 2259+586 is related to the Compton scattering of thermal photons in the magnetar corona and thus reveal coronal time scales and activity.