I review some of the basic observational details of jets from X-ray binaries, or ‘microquasars’. It is shown that in both (Z and Atoll) NS and BHC systems radio emission, and therefore jet formation, is correlated with the presence of hard (30–500 keV) X-ray emission. At γ-ray (> 500 keV) energies, the relation is not so clear. Possible physical connections between the presence of a jet, with a...

X-ray lines have been recently detected in the afterglows of a few gamma-ray bursts. We derive constraints on the physical conditions in the line-emitting gas, using as an example the multiple Kα lines detected by Reeves et al. (2002) in GRB 011211. We argue that models previously discussed in the literature require either a very extreme geometry or too much mass in the line-emitting region. We...

As shown by Maraschi (this volume) the overall spectral energy distribution (SED) of the blazars detected by EGRET shows two peaks, in a ν–νF (ν) plot. With few exceptions, the minimum between these two peaks occurs in the X–ray range. We can exploit this observational fact to constrain the models proposed to account for the SED of blazars, and to reach an important conclusion: the conversion o...

We summarize the current observational picture regarding high-energy emission from Galactic X-ray binaries, reviewing the results of the Compton Gamma Ray Observatory mission. We speculate on the prospects for the GLAST era.

 ABSTRACTBackground: An electron beam generated X-ray spectrum consists of characteristic X-ray and continuous bermsstrahlung. The aim of this research is calculating and comparing X-ray spectra for different target filter of mammograms. Materials and Methods: Monte Carlo is a very powerful tool to simulate a series of different target-filter assembly in order to calculate the X-ray spectra. MC...

Introduction: Unfolding X-ray spectrum is a powerful tool for quality control of X-ray tubes. Generally, the acquisition of the X-ray spectrum in diagnostic radiology departments is complicated and difficult due to high photon flux. Measurement of x ray spectra using radiation detectors could not be performed accurately, because of the pulse pile up. Therefore, indirect methods...

Coal with low ash content has an important role in the coal and steel industry. There are different methods to measure the ash content. The conventional method which is used in most coal mines of Iran, is to burn the coal and measure the remaining ash. A new method has been recently developed at Nuclear Research Center (NRC) of Iran, Which works on the basis of the absorption of the dual en...

this research was conducted to determine the effect of gamma ray (gr) (100 and 150 kgy), sodium hydroxide (50 g/kg dm) and calcium oxide (160 g/kg dm) on gas production parameters and in vitro digestibility of soybean straw. all treatments, except for the gamma ray (100 and 150 kgy) did not have gas production up to 4 hours after incubation and there was a lag time. from 8 to 96 hours of incuba...