We present results from simultaneous optical (SALT) and X-ray (Swift and INTEGRAL) observations of GS 1354-64/BW Cir during the 2015 hard state outburst. During the rising phase, optical/X-ray time series show a strong anti-correlation with X-ray photons lagging optical. Optical and X-ray power spectra show quasi-periodic oscillations at a frequency of ∼ 18 mHz with a confidence level of at lea...

We present results of an infrared-to-X-ray study of 76 bright soft X-ray selected Seyfert galaxies discovered in the ROSAT All-Sky Survey. These objects are characterized by steep X-ray spectra in the 0.2-2.0 keV bandpass with power law energy spectral indices in the range of 1.3 to 8 and a lack of internal absorption by neutral hydrogen. Our sample selection based on hardness ratio yields a me...

We find that the optical magnitudes of GRB990123 observed by ROTSE correlates with the magnitudes extrapolated from the simultaneous BATSE spectra, strongly suggesting that the optical, X-ray and gamma-ray photons originate from a single source. We then show that the broadband optical-gamma-ray spectra can be naturally fit by the saturated Compton model. We also derive the parameters of the Com...

We present the X-ray grating spectra of the recurrent nova RS Ophiuchi during its 2006 outburst, obtained with the XMM-Newton and Chandra observatories. Two weeks after optical maximum, the X-ray spectrum was hard and dominated by emission lines of H-like and He-like ions. The X-ray luminosity was 2.4 × 10 erg cm in the 0.33-10 keV range. The spectra indicate a collisionally

a simple and green synthetic strategy to prepare bao/tio2-zro2 as a solid base catalyst was reported. these materials with various amounts of bao were prepared by the adsorption method. the physical and chemical properties of bao/tio2-zro2 were investigated by x-ray diffraction, x-ray fluorescence, specific surface area and bjh pore size distribution, ft-ir spectroscopy, scanning electron micro...

Three electronic absorption systems for C5 at 511, 445, and 232 nm and one for C6, C8, and C9 centered at 228, 259, and 288 nm have been observed in the gas phase. The C5 chain was produced in both discharge and ablation sources and detected using resonant two-color two-photon ionization spectroscopy involving 10.5 eV photons. The decay of the excited singlet electronic states indicates fast in...