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TGRS Measurements of the Positron Annihilation Spectrum from the Galactic Center

M. J. Harris·B. J. Teegarden·T. L. Cline·N. Gehrels·D. M. Palmer·R. Ramaty·H. Seifert
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Abstract

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 associated continuum due to annihilation via positronium formation. Measurements of the line width and the line-to-continuum ratio allow some constraints to be placed on the interstellar sites where annihilation occurs.

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M. J. Harris, B. J. Teegarden, T. L. Cline, N. Gehrels, D. M. Palmer, R. Ramaty, H. Seifert. 1998-03-20. TGRS Measurements of the Positron Annihilation Spectrum from the Galactic Center. https://doi.org/10.1086/311429

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