Transient Gamma-Ray Spectrometer Measurements of the Positron Annihilation Spectrum from the Galactic Center
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چکیده
منابع مشابه
Tgrs Measurements of the Positron Annihilation Spectrum from the Galactic Center
We have obtained spectra of the Galactic center at energies 400–600 keV from high-resolution data acquired by the TGRS Ge spectrometer on board the WIND mission during 1995–1997. The data were obtained using an on-board occulter, and are relatively free from systematics and backgrounds. Analysis of the spectra reveals a well-resolved electron-positron annihilation line at 511 keV and the associ...
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The electron-positron annihilation spectrum observed by SPI/INTEGRAL during deep Galactic Center region exposure is reported. The line energy (510.954±0.075 keV) is consistent with the unshifted annihilation line. The width of the annihilation line is 2.37±0.25 keV (FWHM), while the strength of the ortho-positronium continuum suggests that the dominant fraction of positrons (94±6%) form positro...
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We study the potential of GLAST to unveil particle dark matter properties with gamma-ray observations of the Galactic center region. We present full GLAST simulations including all gamma-ray sources known to date in a region of 4 degrees around the Galactic center, in addition to the diffuse gamma-ray background and to the dark matter signal. We introduce DMFIT, a tool that allows one to fit ga...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1998
ISSN: 0004-637X
DOI: 10.1086/311429