CaltechAUTHORS
  A Caltech Library Service

Can ^(59)Ni Synthesized in OB Associations Decay to ^(59)Co Before Being Accelerated to Cosmic-ray Energies?

Binns, W. R. and Cummings, A. C. and de Nolfo, G. A. and Israel, M. H. and Leske, R. A. and Mewaldt, R. A. and von Rosenvinge, T. T. and Stone, E. C. and Wiedenbeck, M. E. (2007) Can ^(59)Ni Synthesized in OB Associations Decay to ^(59)Co Before Being Accelerated to Cosmic-ray Energies? In: Proceedings of the 30th International Cosmic Ray Conference. Vol.2. Universidad Nacional Autónoma de México , Merida, Yucatan, Mexico, pp. 27-30. http://resolver.caltech.edu/CaltechAUTHORS:20150501-111243485

[img] PDF - Published Version
See Usage Policy.

147Kb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20150501-111243485

Abstract

Observations from the Cosmic Ray Isotope Spectrometer (CRIS) aboard NASA’s Advanced Composition Explorer (ACE) have shown that all relevant galactic cosmic-ray isotopic ratios measured are consistent with an OB-association origin of galactic cosmic rays (GCRs). Additionally CRIS measurements of the isotopic abundances of ^(59)Ni and ^(59)Co have shown that the 59Ni has completely decayed into ^(59)Co, indicating a delay of >10^5 years between nucleosynthesis and acceleration. However, it has been suggested that shocks generated from high-velocity Wolf-Rayet winds in the OB-association environment must accelerate nuclei synthesized in nearby core-collapse supernovae on a time scale short compared to the ^(59)Ni half-life of 7.6x10^4 years. If this were the case, it would imply that OB associations could not be the source of most galactic cosmic rays. In this paper, we describe the OB-association history and environment and show that the time scales for acceleration are such that most ^(59)Ni should be expected to decay naturally in that setting, strengthening the argument that OB associations are the likely source of a substantial fraction of galactic cosmic rays.


Item Type:Book Section
Related URLs:
URLURL TypeDescription
http://indico.nucleares.unam.mx/getFile.py/access?contribId=359&sessionId=89&resId=0&materialId=paper&confId=4OrganizationArticle
http://adsabs.harvard.edu/abs/2008ICRC....2...27BADSAbstract
Additional Information:Copyright Universidad Nacional Autónoma de México. This research was supported by NASA at Caltech, WU, the JPL, and GSFC (under Grants NAG5-6912 and NAG5-12929).
Group:Space Radiation Laboratory
Funders:
Funding AgencyGrant Number
NASANAG5-6912
NASANAG5-12929
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory2008-20
Record Number:CaltechAUTHORS:20150501-111243485
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20150501-111243485
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:57150
Collection:CaltechAUTHORS
Deposited By: Deborah Miles
Deposited On:02 Jun 2015 01:56
Last Modified:02 Jun 2015 01:56

Repository Staff Only: item control page