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Title: Project Title: Nuclear Astrophysics Data from Radioactive Beam Facilities

The scientific aims of this project have been the evaluation and dissemination of key nuclear reactions in nuclear astrophysics, with a focus on ones to be studied at new radioactive beam facilities worldwide. These aims were maintained during the entire funding period from 2003 - 2006. In the following, a summary of the reactions evaluated during this period is provided. Year 1 (2003-04): {sup 21}Na(p,{gamma}){sup 22}Mg and {sup 18}Ne({alpha},p){sup 21}Na - The importance of the {sup 21}Na(p,{gamma}){sup 22}Mg and the {sup 18}Ne({alpha},p){sup 21}Na reactions in models of exploding stars has been well documented: the first is connected to the production of the radioisotope {sup 22}Na in nova nucleosynthesis, while the second is a key bridge between the Hot-CNO cycles and the rp-process in X-ray bursts. By the end of Summer 2004, our group had updated these reaction rates to include all published data up to September 2004, and cast the reaction rates into standard analytical and tabular formats with the assistance of Oak Ridge National Laboratory's computational infrastructure for reaction rates. Since September 2004, ongoing experiments on these two reactions have been completed, with our group's participation in both: {sup 21}Na(p,{gamma}){sup 22}Mg at the TRIUMF-ISAC laboratory (DRAGON collaboration), and 18Ne({alpha},p){supmore » 21}Na at Argonne National Laboratory (collaboration with Ernst Rehm, Argonne). The data from the former was subsequently published and included in our evaluation. Publication from the latter still awaits independent confirmation of the experimental results. Year 2 (2004-05): The 25Al(p,{gamma}){sup 26}Si and {sup 13}N(p,{gamma})14O reactions - For Year 2, we worked on evaluations of the {sup 25}Al(p,{gamma}){sup 26}Si and {sup 13}N(p,{gamma}){sup 14}O reactions, in accordance with our proposed deliverables and following similar standard procedures to those used in Year 1. The {sup 25}Al(p,{gamma}){sup 26}Si reaction is a key uncertainty in the understanding the origin of galactic {sup 26}Al, a target radioisotope for gamma ray astronomy; the {sup 13}N(p,{gamma}){sup 14}O reaction in turn is the trigger reaction for the transition into the Hot-CNO cycles in novae and X-ray bursts. A graduate student of mine, who has been supported part-time by this grant, completed the evaluation of the {sup 25}Al(p,{gamma}){sup 26}Si reaction as part of his plans to measure this reaction at TRIUMF for his Ph.D. thesis project. I also hired a part-time undergraduate student for the 2004-05 academic year to assist with the evaluations, including that of the {sup 13}N(p,{gamma}){sup 14}O reaction. Year 3 (2005-06): The {sup 40}Ca({alpha},{gamma}){sup 44}Ti and {sup 26}Al(p,{gamma}){sup 27}Si reactions - This year's progress was closely coupled to new results coming from our collaboration on the DRAGON spectrometer team at TRIUMF. The {sup 40}Ca({alpha},{gamma}){sup 44}Ti and {sup 26}Al(p,{gamma}){sup 27}Si reactions were both measured, and significant modifications to their respective reaction rates were required. Both are required input toward predicting the respective amounts of Titanium-44 and Aluminum-26 produced in our galaxy, in supernovae, massive stars, and nova explosions. The {sup 26}Al(p,{gamma}){sup 27}Si reaction rate was successfully completed. The {sup 40}Ca({alpha},{gamma}){sup 44}Ti reaction in particular served as the Ph.D. thesis for Christian Ouellet, and therefore the evaluation of this rate fell naturally within his thesis project. Christian successfully defended his thesis in 2007 and is now working for me on the McMaster DOE-funded Nuclear Data Project. In light of the recent data from his thesis, Christian is now putting the final touches on this evaluation, and will disseminate it through the Oak Ridge National Laboratory reaction rate database.« less
Authors:
Publication Date:
OSTI Identifier:
926087
Report Number(s):
DOE/ER/41251-3 Final Report
TRN: US1007620
DOE Contract Number:
FG02-03ER41251
Resource Type:
Technical Report
Research Org:
McMaster University, Office of Research Services, Hamilton, Ontario, Canada
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ANL; ASTRONOMY; ASTROPHYSICS; EVALUATION; EXPLOSIONS; MODIFICATIONS; NOVAE; NUCLEAR REACTIONS; NUCLEOSYNTHESIS; ORIGIN; PRODUCTION; RADIOISOTOPES; REACTION KINETICS; SPECTROMETERS; STARS; SUPERNOVAE; TARGETS; TITANIUM 44