Astronomy and Astrophysics – Astronomy
Scientific paper
Sep 1999
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1999apj...523l..61w&link_type=abstract
The Astrophysical Journal, Volume 523, Issue 1, pp. L61-L64.
Astronomy and Astrophysics
Astronomy
45
Acceleration Of Particles, Ism: Cosmic Rays, Nuclear Reactions, Nucleosynthesis, Abundances, Stars: Supernovae: General
Scientific paper
Measurements of the abundances of cosmic-ray ^59Ni and ^59Co are reported from the Cosmic-Ray Isotope Spectrometer (CRIS) on the Advanced Composition Explorer. These nuclides form a parent-daughter pair in a radioactive decay which can occur only by electron capture. This decay cannot occur once the nuclei are accelerated to high energies and stripped of their electrons. The CRIS data indicate that the decay of ^59Ni to ^59Co has occurred, leading to the conclusion that a time longer than the 7.6x10^4 yr half-life of ^59Ni elapsed before the particles were accelerated. Such long delays indicate the acceleration of old, stellar or interstellar material rather than fresh supernova ejecta. For cosmic-ray source material to have the composition of supernova ejecta would require that these ejecta not undergo significant mixing with normal interstellar gas before ~10^5 yr has elapsed.
Binns Robert W.
Christian Eric R.
Cummings Alan C.
Dougherty Brian L.
Hink Paul L.
No associations
LandOfFree
Constraints on the Time Delay between Nucleosynthesis and Cosmic-Ray Acceleration from Observations of ^59NI and ^59CO 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 Constraints on the Time Delay between Nucleosynthesis and Cosmic-Ray Acceleration from Observations of ^59NI and ^59CO, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Constraints on the Time Delay between Nucleosynthesis and Cosmic-Ray Acceleration from Observations of ^59NI and ^59CO will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1769348