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2 edition of A Large scale height galactic component of the diffuse 2-60 keV background found in the catalog.

A Large scale height galactic component of the diffuse 2-60 keV background

A Large scale height galactic component of the diffuse 2-60 keV background

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  • 39 Currently reading

Published by National Aeronautics and Space Administration, Goddard Space Flight Center in Greenbelt, Md .
Written in English

    Subjects:
  • Galaxies,
  • Stars,
  • X-rays

  • Edition Notes

    StatementD. Iwan ... [et al.]
    SeriesNASA technical memorandum -- 83837
    ContributionsIwan, D., Goddard Space Flight Center
    The Physical Object
    FormatMicroform
    Pagination1 v.
    ID Numbers
    Open LibraryOL14926092M

    At keV, the background is about mCrab (1 x cts cm-2 s-1 keV-1). In the keV band, the limiting sensitivity for detailed spectral analysis is expected to be about 1 mCrab (1 x cts cm-2 s-1 keV-1) or 1% of the instrument background. This sensitivity can be reached at 3 [[sigma]] in 10 5 s. The instrument is being provided. Galactic Magnetic Field Basics • Two components: large, small • Aligned with the disk • Follows the spiral arms (?) • Local field is clockwise • Sagittarius field is counter-cw • Determining the existence and location of additional reversals will help us understand the origin and evolution of the field - .

    even large distances from the Galactic plane. In practice, however, this simple picture is complicated because the Hii gas distribution is broad with typical scale height ∼1 kpc, while the distribution of high energy electrons is narrow and concentrated near the Galactic plane due to the large energy losses. We attempt to simultaneously explain the recently observed keV x-ray line in the analysis of XMM-Newton telescope data and the Galactic Center gamma ray excess observed by the Fermi Gamma Ray Space Telescope within an Abelian gauge extension of the standard model. We consider a two component dark matter scenario with tree level mass difference keV such that the heavier one .

    @article{osti_, title = {THE GALACTIC POSITRON ANNIHILATION RADIATION AND THE PROPAGATION OF POSITRONS IN THE INTERSTELLAR MEDIUM}, author = {Higdon, J C and Lingenfelter, R E and Rothschild, R. E.}, abstractNote = {The ratio of the luminosity of diffuse keV positron annihilation radiation, measured by INTEGRAL in its four years, from a Galactic 'positron . We apply a likelihood analysis to pulsar detections, pulsar upper limits, and diffuse background measurements from the OSSE and EGRET instruments on the.


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A Large scale height galactic component of the diffuse 2-60 keV background Download PDF EPUB FB2

The diffuse keV X-ray background has a galactic component clearly detectable by its strong variation with both galactic latitude and longitude. This galactic component is typically 10 percent of the extragalactic background toward the galactic center, half that strong toward the anticenter, and extrapolated to a few percent of the Cited by:   The diffuse keV X-ray background has a galactic component clearly detectable by its strong variation with both galactic latitude and longitude.

This galactic component is typically 10 percent of the extragalactic background toward the galactic center, half that strong toward the anticenter, and extrapolated to a few percent of the extragalactic background toward the galactic : D.

Iwan, F. Marshall, E. Boldt, R. Mushotzky, R. Shafer, A. Stottlemyer. Get this from a library. A Large scale height galactic component of the diffuse keV background.

[D Iwan; Goddard Space Flight Center.;]. The diffuse keV X-ray background has a galactic component clearly detectable by its strong variation with both galactic latitude and longitude. This galactic component is typically 10 percent of the extragalactic background toward the galactic center, half that strong toward the anticenter, and extrapolated to a few percent of the.

A LARGE SCALE HEIGHT GALACTIC COMPONENT OF THE DIFFUSE keV BACKGROUND DeAnn Iwani, F.E. Marsoall, E.A. Boldt, R.F Mushotzky, R.A. Shafer', and A. Stottlemyer1 Laboratory for High Energy Astrophysics NASA/Goddard Space Flight Center Greenbelt, Maryland ABSTRACT The diffuse keV X-ray background has a galactic component clearly.

Evidence for this comes from the generally reported isotropy above several keV [1, 2, 3] and the observed galactic latitude dependence at keV, believed to result from the interstellar attenuation of these low energy photons in passage through the Galaxy [4, 5].

() Evidence for a Galactic Component of the Diffuse X-Ray Background. Boldt's research works with 8, citations and reads, including: Large-Scale Fluctuations in the X-Ray Background.

Fluctuations in the high latitude surface brightness of a few percent are visible as is a general brightening towards the galactic plane. HEAO-1 and BBXRT X-Ray Observations (12) Large Scale Structure which might be present in the data. Large Scale Structure signals may be characterized as Microscopic, Macroscopic, or All-Sky.

We have analyzed the ROSAT PSPC all-sky survey maps of the soft X-ray background (SXRB) in the 3/4 keV band. One approach was to study the large-scale distribution of the X-ray emission with a multipole analysis. Here a significant dipole toward the galactic center region was found.

This is interpreted in terms of variation of distant X-ray. Burton's 74 research works with 3, citations and reads, including: Evidence for an Interaction in the Nearest Starbursting Dwarf Irregular Galaxy IC   We assume that the Galactic source of keV observed, in the direction of the Galactic Center are from two different origins: a steady diffuse component, and a variable point source at or near the Galactic Center.

We will consider here the diffuse source of keV only. The keV gamma‐ray line was discovered in and confirmed. The Galactic ridge observations were performed in September ofwith the PCA instrument onboard the RXTE satellite.

The PCA (Jahoda et al. ) has a total collecting area of cm2, an energy range of 2 −60 keV, and energy resolution of ˘18% at 6 keV. The collimator eld of view is approximately circular (2 diameter) with FWHM of 1. longitude reveals the presence of two components: a thin disk of full width ∼Galactic mid-plane, and a broad component which can be approximated as a Gaussian distribution with FWHM of about 4.

Assuming an average distance of 16 kpc to the edge of the galaxy, a scale height. With the cm 2 total effective area and an extremely low background level, the LAC has the highest sensitivity (down to ∼5×10 −12 erg/cm 2 /s) to the keV cosmic X-rays ever achieved.

These instrumentations, as well as many scientific results, have been published in Publ. Astron. Soc. Japan, 41, No.3 as a special issue (hereafter referred to as [PASJ]). During the dip, the keV X-ray flux drops by a factor of about 3, and, at the lowest point of the dip, the X-ray spectrum is considerably softer than at nondip times.

We find that the 4U dip is best explained by absorption of the inner part of an accretion disk. Francis E. Marshall Current Responsibilities: Director, RXTE Science Operations Center Mission Scientist, Constellation-X Research Areas: Gamma-ray bursts, cosmic X-ray background, galactic X-ray emission, pulsars.

Galactic Component Previous studies using this data base (Shafer ; Twan et al. 19~) have shown that the strongest large-scale feature in the sky at galactic latitudes greater than 10 degrees is due to the galaxy. This component has an effective scale height of. DIFFUSE LOW-FREQUENCY GALACTIC COMPONENTS Foreground components include: • Large-scale loops have been identified in low frequency surveys such as that at MHz Latitude widths of Galactic components (Longitudes o – oo oand 20 - ).

* The HEAO-1 A-2 LED Catalog of High-Energy X-ray Sources can be found in BROWSE as A2LED. This catalog is the result of a study of the diffuse X-ray sky over the bands of X-ray energies keV and keV from August until January using data obtained with.

Joint spectral analysis of RXTE Proportional Counter Array and ASCA Gas Imaging Spectrometer data for NGC and NGC reveals the presence of 5 × ergs cm-2 s-1 of 2 10 keV emission emanating from a region outside of the optical galaxy and of a spectral hardness intermediate between the galactic hot interstellar gas and X-ray binary.

In the discussion that follows we use the keV background flux derived from high galactic latitude fields in the longitude range ° background intensity, although a residual galactic contribution cannot be excluded; the adopted value in this band is x 10~8erg cm~2s~isr~~.The galactic ridge is a region of the inner galaxy that is coincident with the galactic plane of the Milky Way.

It can be seen from Earth as a band of stars which is interrupted by 'dust lanes'. In these 'dust lanes' the dust in the gaseous galactic disk (or plane) blocks the visible light of the background stars.background and continuum emission for the whole sky.

Based on the exponential-disk grid maps, we characterise the emission extent of 26Al to find scale parameters R0 = + − kpc and z0 = + − kpc, however the 60Fe lines are too weak to spa-tially constrain the emission.

Based on a point source model test across the Galactic.