Astronomy and Astrophysics – Astrophysics
Scientific paper
1999-02-04
Nucl.Phys.Proc.Suppl. 80 (2000) 215-217
Astronomy and Astrophysics
Astrophysics
4 pages
Scientific paper
10.1016/S0920-5632(99)00846-4
The most energetic part of the electromagnetic spectrum bears the purest clues to the synthesis of atomic nuclei in the universe. The decay of radioactive species, synthesized in stellar environments and ejected into the interstellar medium, gives rise to specific gamma ray lines. The observations gathered up to now show evidence for radioactivities throughout the galactic disk, in young supernova remnants (Cas A, Vela), and in nearby extragalactic supernovae (SN 1987A, SN 1991T and SN1998bu), in the form of specific gamma ray lines resulting, respectively, from the radioactive decay of 26Al, 44Ti and 56Co. The various astrophysical sites of thermal nucleosynthesis of the radioactive nuclei were discussed: AGB and Wolf-Rayet stars, novae, and type Ia and type II supernovae. Nuclear excitations by fast particles also produce gamma ray lines which have been observed in great detail from solar flares, and more hypothetically from active star forming regions where massive supernovae and WR stars abound. This non thermal process and its nucleosynthetic consequences was reviewed. The 511 keV line arising from e+ + e- annihilation also provides important information on explosive nucleosynthesis, as well as on the nature of the interstellar medium where the positrons annihilate. INTEGRAL, the main mission devoted to high resolution nuclear spectroscopy, should lead to important progress in this field.
Cass'e Michel
Ramaty Reuven
Vangioni-Flam Elisabeth
No associations
LandOfFree
Nucleosynthesis and Gamma Ray-Line Astronomy 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 Nucleosynthesis and Gamma Ray-Line Astronomy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nucleosynthesis and Gamma Ray-Line Astronomy will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-231900