It is thought that ultraluminous X-ray sources (ULXs) are mainly powered by super-Eddington accreting neutron stars or black holes as shown recent discovery of pulsations and relativistic winds. This work presents a follow up study the spectral evolution over two decades pulsing ULX NGC 1313 X-2, in order to understand structure accretion disc. The primary objective determine shape nature domin...

We present a summary of our ongoing efforts to study one of the brightest ultraluminous X-ray source, NGC 1313 X-2. Despite a large coverage in the X-rays, much of the information we have about the source and its environment comes from optical wavelenghts. Here, we report on the properties of the stellar environment, and the differences in the optical counterpart between our two observing epoch...

We report the results of an analysis of two XMM-Newton EPIC-pn spectra of the bright ultraluminous X-ray source M81 X-9 (Holmberg IX X-1) obtained in snapshot observations. Soft thermal emission is clearly revealed in spectra dominated by hard power-law components. Depending on the model used, M81 X-9 was observed at a luminosity of LX 1⁄4 1:0 1:6 ð Þ ; 10 ergs s 1 (0.3–10.0 keV). The variabili...

Hong-Ya Xu,1 Liang Huang,2 Danhong Huang,3,4 and Ying-Cheng Lai1,5,* 1School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287, USA 2School of Physical Science and Technology, and Key Laboratory for Magnetism and Magnetic Materials of MOE, Lanzhou University, Lanzhou, Gansu 730000, China 3Air Force Research Laboratory, Space Vehicles Directorate, Kir...

In this paper, an injection-seeded nanosecond optical parametric generation (OPG) using BBO crystal, which combines relatively low thresholds with a simple and compact configuration, was demonstrated. By seeding externally distributed feedback (DFB) diode laser at 1313 nm wavelength, pumped by 355 pulse, the maximum blue output power of 1.36 W rate 100 Hz linewidth less than 0.13 were obtained,...