TGRS Measurements of the Positron Annihilation Spectrum from the Galactic Center

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.

20 pp., 4 figs. Ap. J. Letters in press

Cited by in corpus (25)

• The all-sky distribution of 511 keV electron-positron annihilation emission
• Early SPI/INTEGRAL measurements of galactic 511 keV line emission from positron annihilation
• The 511 keV emission from positron annihilation in the Galaxy
• Spectral analysis of the Galactic e+e- annihilation emission
• Positron annihilation spectrum from the Galactic Center region observed by SPI/INTEGRAL
• Early SPI/INTEGRAL contraints on the morphology of the 511 keV line emission in the 4th galactic quadrant
• Constraints on dark matter and the shape of the Milky Way dark halo from the 511 keV line
• The lives and deaths of positrons in the interstellar medium
• Astrophysical constraints from gamma-ray spectroscopy
• INTEGRAL/SPI Limits on Electron-Positron Annihilation Radiation from the Galactic Plane
• Unified 1-D Simulations of Gamma-Ray Line Emission from Type Ia Supernovae
• Constraints on a mixed model of dark matter particles and primordial black holes from the Galactic 511 keV line
• Supernovae and Positron Annihilation
• MGGPOD: a Monte Carlo Suite for Modeling Instrumental Line and Continuum Backgrounds in Gamma-Ray Astronomy
• Detection of the 511 keV Galactic positron annihilation line with COSI
• Transient Gamma Ray Spectrometer Measurements of Gamma-Ray Lines from Novae. I. Limits on the Positron Annihilation Line in Five Individual Novae
• Positron Annihilation on Polycyclic Aromatic Hydrocarbon molecules in the Interstellar Medium
• Imaging the 511 keV positron annihilation sky with COSI
• Advanced Compton Telescope Designs and SN Science
• Transient Gamma Ray Spectrometer Measurements of Gamma-Ray Lines from Novae. II. Constraining the Galactic Nova Rate from a Survey of the Southern Sky during 1995-1997
• Confronting the Galactic 511 keV emission with $B-L$ gauge boson dark matter
• Gamma-Ray Line Astronomy
• Constraints on stellar yields and SNe from gamma-ray line observations
• Distribution of Positron Annihilation Radiation
• Darker matter generating from the dark