Annihilation radiation from the galactic center - Positrons in dust?

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

34

Galactic Nuclei, Gamma Rays, Heao 3, Interstellar Gas, Milky Way Galaxy, Positron Annihilation, Abundance, Cosmic Dust, Free Electrons, Galactic Radiation, Hydrogen, Interstellar Matter, Ultraviolet Radiation

Scientific paper

HEAO 3 autumn 1979 gamma-ray observations of the galactic center indicate that the 2 gamma 0.511 MeV annihilation line contains - as compared with the observed 3 gamma continuum, which is also emitted in the annihilation process - more than 2 times as many photons as can be accounted for by standard models, in which positron annihilation takes place in an ionized interstellar gas. Positron annihilation in the interstellar medium is discussed, and it is shown that a significant increase of the line intensity, sufficient to explain the observed spectrum, may arise from positron annihilation on grains of interstellar dust. Dust, in spite of its small abundance, is bound to play a significant role in positron annihilation because its projected surface area, about 10 to the -21st sq cm per gas atom, is three orders of magnitude more than the Thomson cross section, relevant annihilation rates on ionized gas. Approximate analytic expressions for the rates of various annihilation processes occurring in the interstellar medium are given.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Annihilation radiation from the galactic center - Positrons in dust? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Annihilation radiation from the galactic center - Positrons in dust?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Annihilation radiation from the galactic center - Positrons in dust? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1591111

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.