scholarly journals Fe VIII, IX, and X Line Emission From the Soft X-ray Background: Previous Limits and a Future Measurement

1990 ◽  
Vol 115 ◽  
pp. 160-163
Author(s):  
J. J. Bloch ◽  
W. C. Priedhorsky ◽  
Barham W. Smith
Keyword(s):  
Broad Band ◽  
Pulse Height ◽  
Line Emission ◽  
Elemental Abundance ◽  
Cluster Emission ◽  
X Ray ◽  
Pulse Height Analysis ◽  
Emission Models ◽  
X Ray Background ◽  
Imaging Sensors

AbstractWe discuss pulse height analysis of Be band data in relation to the important 72 eV Fe line cluster emission from the soft X-ray background (SXRB). Pulse height fits to the Be band data suggest that the Fe lines must be suppressed by a factor of ~10 with respect to the rest of the X-ray spectrum. The broad band rates and the mean energy of the pulse height data for the Be band can be brought into agreement by using depleted elemental abundance emission models. A planned measurement of the SXRB Fe lines using the Array of Low Energy X-ray Imaging Sensors (ALEXIS) experiment could resolve this issue.

A new soft x-ray pulse height analysis array in the HL-2A tokamak

2009 ◽  
Vol 80 (12) ◽  
pp. 126104 ◽  
Author(s):  
Y. P. Zhang ◽  
Yi Liu ◽  
J. W. Yang ◽  
X. Y. Song ◽  
M. Liao ◽  
...  
Keyword(s):  
Pulse Height ◽  
X Ray ◽  
Pulse Height Analysis

scholarly journals Chemical Bonding and the Sulfur K X-Ray Spectrum

1965 ◽  
Vol 9 ◽  
pp. 354-364 ◽  
Author(s):  
D. W. Wilbur ◽  
J. W. Gofman
Keyword(s):  
Electronic Structure ◽  
Single Crystal ◽  
Organic Compounds ◽  
Sulfur Atom ◽  
Chemical Bonding ◽  
Proportional Counter ◽  
Pulse Height ◽  
X Ray ◽  
Pulse Height Analysis ◽  
Chemical States

AbstractAn investigation has been made of the relative Kβ intensities in different chemical states of the sulfur atom using the Kα lines, with appropriate corrections, to provide the intensity standards. Both inorganic and organic compounds were included in the study. The data for each compound appear to be reliable to about ± 0.5%, while the whole series of compounds shows a variation greater than 20% in the corrected Kβ/Kα ratios. Energies were also measured, particularly the Kα energies, and their shifts were studied relative to the Kβ, intensity shifts. The work was done with a plane, single-crystal, helium-path spectrometer with proportional counter and pulse-height analysis for detection. The results are indicative of the usefulness of the method both in clarifying an uncertain chemical state and in studying the electronic structure of the bonded atom.

scholarly journals Review of GRANAT Observations of AGNs

1994 ◽  
Vol 159 ◽  
pp. 63-72 ◽  
Author(s):  
E. Churazov ◽  
M. Gilfanov ◽  
A. Finoguenov ◽  
R. Sunyaev ◽  
M. Chernyakova ◽  
...  
Keyword(s):  
Time Scales ◽  
Gamma Ray ◽  
Broad Band ◽  
Band 3 ◽  
X Rays ◽  
X Ray ◽  
X Ray Background

Brief review of AGNs observations in the X-ray / soft gamma-ray bands with the orbital observatory GRANAT is presented.For three well known bright objects (3C273, NGC4151 and Cen A) broad band (3 keV–few hundreds keV) spectra have been obtained. Imaging capabilities allowed accurate (several arcminutes) identification of these objects with sources of hard X-rays.The spectrum of NGC4151 above ≈ 50 keV was found to be much steeper than that in most of the previous observations, while in standard X-ray band the spectrum agrees with observed previously. The comparison of the observed spectra with that of the X-Ray Background (XRB) indicates that sources similar to NGC4151 could reproduce the shape of XRB spectrum in 3–60 keV band.Cen A was observed in the very low state during most of observations in 1990–1993, except for two observations in 1991. The variability of the hard X-ray flux has been detected on the time scales of several days.

Three-band observations of the soft X-ray background and some implications of thermal emission models

1977 ◽  
Vol 213 ◽  
pp. 405 ◽  
Author(s):  
P. Burstein ◽  
R. J. Borken ◽  
W. L. Kraushaar ◽  
W. T. Sanders
Keyword(s):  
Thermal Emission ◽  
X Ray ◽  
Emission Models ◽  
X Ray Background

Line Emission in the X-Ray Background

1971 ◽  
Vol 166 ◽  
pp. L9 ◽  
Author(s):  
Seth Shulman ◽  
Gilbert Fritz ◽  
John F. Meekins ◽  
T. A. Chubb ◽  
H. Friedman ◽  
...  
Keyword(s):  
Line Emission ◽  
X Ray ◽  
X Ray Background

Pulse-Height Selection in X-Ray Fluorescence

1960 ◽  
Vol 4 ◽  
pp. 370-381
Author(s):  
Kurt F.J. Heinrich
Keyword(s):  
Energy Levels ◽  
Pulse Height ◽  
Fluorescence Analysis ◽  
Higher Order ◽  
Pulse Height Analyzer ◽  
X Ray ◽  
Qualitative And Quantitative ◽  
Systematic Application ◽  
Pulse Height Analysis ◽  
Qualitative Work

AbstractPulse-height analysis is a valuable tool in X-ray fluorescence analysis, both for qualitative and quantitative purposes. The elimination of higher order interferences permits determinations that would otherwise be very difficult or impossible, The systematic application of pulse-height analysis in qualitative work greatly simplifies the interpretation of complex spectra. In certain cases one can apply nondispersive analysis, relying on the pulse-height analyzer alone for separating energy levels of X-ray photons. Technique and limitations of pulse-height analysis will be discussed.

scholarly journals Cosmological Evolution of X-ray Selected AGNs and Synthesis of the X-ray Background

2013 ◽  
Vol 9 (S304) ◽  
pp. 125-131
Author(s):  
Yoshihiro Ueda ◽  
Masayuki Akiyama ◽  
Günther Hasinger ◽  
Takamitsu Miyaji ◽  
Michael G. Watson
Keyword(s):  
Broad Band ◽  
Likelihood Method ◽  
Energy Bands ◽  
Redshift Distribution ◽  
Absorption Function ◽  
X Ray ◽  
Standard Population ◽  
Rate Versus ◽  
X Ray Background ◽  
Biased Samples

AbstractX-ray surveys provide us with one of the least biased samples of Active Galactic Nuclei (AGNs) against obscuration. Here we present the most up-to-date AGN X-ray luminosity function (XLF) and absorption function over the redshift range from 0 to 5, using the largest, highly complete sample ever available obtained from surveys of various depth, depth, and energy bands. We utilize a maximum likelihood method to reproduce the count-rate versus redshift distribution for each survey, by taking into account the evolution of the absorbed fraction, contribution from Compton-thick AGNs, and AGN broad band X-ray spectra including reflection components from tori based on the luminosity and redshift dependent unified scheme. We find that the shape of the XLF at z ~ 1–3 is significantly different from that in the local universe, for which the luminosity dependent density evolution (LDDE) model gives the best description. These results establish the standard population synthesis model of the X-Ray Background (XRB), which well reproduces the source counts in both soft and hard bands, the observed fractions of Compton-thick AGNs, and the spectrum of the XRB.

scholarly journals X-Ray Emission Analysis by Pulse Height Analysis

RADIOISOTOPES ◽  
1964 ◽  
Vol 13 (5) ◽  
pp. 355-361 ◽  
Author(s):  
Hiroshi IMAMURA ◽  
Kaoru UCHIDA ◽  
Hiroshi TOMINAGA
Keyword(s):  
Pulse Height ◽  
Emission Analysis ◽  
X Ray ◽  
Pulse Height Analysis
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