Positron annihilation in the interstellar medium
1991; IOP Publishing; Volume: 378; Linguagem: Inglês
10.1086/170417
ISSN1538-4357
AutoresNidhal Guessoum, R. Ramaty, R. E. Lingenfelter,
Tópico(s)Astro and Planetary Science
Resumoview Abstract Citations (108) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Positron Annihilation in the Interstellar Medium Guessoum, Nidhal ; Ramaty, Reuven ; Lingenfelter, Richard E. Abstract Positronium formation and annihilation are studied in a model for the interstellar medium consisting of cold cloud cores, warm partially ionized cloud envelopes, and hot intercloud gas. The gamma-ray spectra resulting from positron annihilation in these components of the interstellar medium are calculated. The spectra from the individual components are then combined, using two limiting assumptions for the propagation of the positrons, namely, that the positrons propagate freely throughout the interstellar medium, and that the positrons are excluded from the cold cloud cores. In the first case, the bulk of the positrons annihilate in the cloud cores and the annihilation line exhibits broad wings resulting from the annihilation of positronium formed by charge exchange in flight. In the second case, the positrons annihilate mainly in the warm envelopes, and the line wings are suppressed. Publication: The Astrophysical Journal Pub Date: September 1991 DOI: 10.1086/170417 Bibcode: 1991ApJ...378..170G Keywords: Astronomical Models; Gamma Ray Spectra; Interstellar Matter; Positron Annihilation; Antiparticles; Interstellar Magnetic Fields; Milky Way Galaxy; Positronium; Astrophysics; ELEMENTARY PARTICLES; GAMMA RAYS: GENERAL; INTERSTELLAR: GRAINS; INTERSTELLAR: MAGNETIC FIELDS; INTERSTELLAR: MATTER full text sources ADS |
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