scholarly journals Small‐Scale Variations in the \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $\frac{1}{4}$ \end{document} keV X‐Ray Background along the Galactic Plane

1997 ◽  
Vol 491 (1) ◽  
pp. 165-171 ◽  
Author(s):  
Sangwook Park ◽  
John P. Finley ◽  
S. L. Snowden
1970 ◽  
Vol 37 ◽  
pp. 406-407
Author(s):  
M. J. Rees

Below 1 keV, analyses of X-ray background data are complicated by galactic absorption effects, which cause the received intensity to vary with galactic latitude. Bowyer et al. (1968) observed that the diffuse background did not fall off as rapidly as was expected towards the galactic plane. One plausible interpretation of their data would be to suppose that a significant flux of soft X-rays emanates from the disc itself. I wish to discuss what could be inferred about the latter component from improved observations of its latitude-dependence, and by indirect methods.


1973 ◽  
Vol 182 ◽  
pp. 405 ◽  
Author(s):  
A. Cavaliere ◽  
A. Friedland ◽  
H. Gursky ◽  
G. Spada
Keyword(s):  
X Ray ◽  

1994 ◽  
Vol 424 ◽  
pp. 671
Author(s):  
John M. Stanford ◽  
Jean-Pierre Caillault

1997 ◽  
Vol 166 ◽  
pp. 83-90 ◽  
Author(s):  
W.T. Sanders ◽  
R.J. Edgar ◽  
D.A. Liedahl ◽  
J.P. Morgenthaler

AbstractThe Diffuse X-ray Spectrometer (DXS) obtained spectra of the low energy X-ray (44 – 83 Å) diffuse background near the galactic plane from galactic longitudes 150° ≲ l ≲ 300° with ≲ 3 Å spectral resolution and ~ 15° angular resolution. Thus, DXS measured X-ray spectra that arise almost entirely from within the Local Bubble. The DXS spectra show emission lines and emission-line blends, indicating that the source of the X-ray emission is thermal – hot plasma in the Local Bubble. The measured spectra are not consistent with those predicted by standard coronal models, either with solar abundances or depleted abundances, over the temperature range 105 – 107 K. The measured spectra are also inconsistent with the predictions of various non-equilibrium models. A nearly acceptable fit to DXS spectra can be achieved using a hybrid model that combines the Raymond & Smith ionization balance calculation with recently calculated (by DAL) ionic emission lines.


1997 ◽  
Vol 166 ◽  
pp. 321-324
Author(s):  
R. Warwick ◽  
I. Hutchinson ◽  
R. Willingale ◽  
K. Kuntz ◽  
S. Snowden

AbstractAn overlapping set of ROSAT PSPC observations made in a region of very low Galactic foreground column density, has been used to investigate variations in the soft X-ray background on angular scales of 15′ – 5°. In the ¼ keV band there is a clear inverse correlation of the count-rate with the line-of-sight hydrogen column density. However, after correcting for this absorption effect, strong residual fluctuations remain in the data, with an amplitude which is significantly larger than that due to the counting statistics or the confusion of unresolved discrete sources. In contrast a similar analysis for the ¾ and 1.5 keV ROSAT bands shows no evidence for an excess signal. The most likely origin of the ¼ keV fluctuations would seem to be in a patchy distribution of ~ 106 K gas in the Galactic halo.


1997 ◽  
Vol 166 ◽  
pp. 325-328
Author(s):  
S. Park ◽  
J.P. Finley ◽  
S.L. Snowden

Abstract42 ROSAT PSPC pointed observations in the Galactic plane (l ~ 4° – 26°) are mosaicked in order to study the spatial structure of the X-ray emitting gas in the Local Hot Bubble (LHB). Degree scale X-ray intensity variations are detected at the ±10% level in the ¼ keV band, which imply a likely influence from a clumpy boundary shell of the LHB in the observed ¼ keV band X-ray background. The possible origins of such a clumpy boundary structure of the LHB are discussed.


1990 ◽  
Vol 139 ◽  
pp. 408-409
Author(s):  
X. Barcons ◽  
A. C. Fabian

The spatial distribution of the 1–3 keV X-ray background (XRB) in five Einstein Observatory Imaging Proportional Counter fields has been analyzed. The autocorrelation function does not exceed 9% on scales ~5′. The observed count probability distribution is then used to check the source number-flux distribution at faint levels. Agreement with the Einstein Observatory deep survey is obtained. A cutoff in the number-flux distribution for a Euclidean population of sources at a flux approximately one-half of the deep survey limit, previously suggested by Hamilton and Helfand (1987), is also inferred.


1998 ◽  
Vol 188 ◽  
pp. 197-200
Author(s):  
H. Inoue ◽  
T. Takahashi ◽  
Y. Ueda ◽  
A. Yamashita ◽  
Y. Ishisaki ◽  
...  

The X-ray background in the energy range above 2 keV is highly uniform except for an excess component along the Galactic plane. The excess along the plane is considered to be associated with our Galaxy, whereas the rest of the emission is believed to be of extragalactic origin. In this paper, the X-ray background at high Galactic latitude is discussed and is designated as the CXB (cosmic X-ray background) to distinguish it from the Galactic origin.


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