The influence of the level structure of sup 20 Na upon the stellar reaction rate for sup 19 Ne(p,. gamma. ) sup 20 Na

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6099567

Lamm, L O

The level structure of {sup 20}Na has been measured up to excitation energies of 3.33 MeV using the charge-exchange reaction {sup 20}Ne({sup 3}He,t){sup 20}Na. Angular distributions have been measured for 14 levels at laboratory angles ranging from 10 to 60 degrees. Assignments of spin and parties have been made for the levels based on DWBA analysis of the angular distributions and comparisons with the level structure of the analog nuclei. The reaction rate for {sup 19}Ne(p,{gamma}){sup 20}Na has been calculated to include the effects of the resonant levels of temperatures of interest in the operation of the hot CNO cycle. The result is an increase of nearly three orders of magnitude in the stellar reaction rate for {sup 19}Ne(p,{gamma}){sup 20}Na, as compared to previous estimates made before the measurement of the level structure of {sup 20}Na. This increase may indicate that {sup 19}Ne (p,{gamma}){sup 20}Na is the sought after breakout mechanism to allow for the transport of mass from the CNO region into the Ne-Na-Mg regions, with applications for the rp-process and the possible explanation of the observed neon overabundances in some nova events. A detailed description of the experiment is given, including a discussion of the development of a new type of position sensitive detector for use with the broad range magnetic spectrograph which has allowed, for the first time, the unambiguous identification to tritons within the spectrograph.

• Research Organization: Notre Dame Univ., IN (USA)
• OSTI ID: 6099567
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
ALKALI METAL ISOTOPES
ANGULAR DISTRIBUTION
BARYON REACTIONS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CHARGE-EXCHANGE REACTIONS
CHARGED PARTICLES
CHARGED-PARTICLE REACTIONS
CNO CYCLE
DIRECT REACTIONS
DISTRIBUTION
ELEMENT ABUNDANCE
ENERGY RANGE
ERUPTIVE VARIABLE STARS
EVEN-ODD NUCLEI
HADRON REACTIONS
HELIUM 3 REACTIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
MASS TRANSFER
MEV RANGE
MEV RANGE 01-10
NEON 19
NEON 20 TARGET
NEON ISOTOPES
NOVAE
NUCLEAR REACTION KINETICS
NUCLEAR REACTIONS
NUCLEAR STRUCTURE
NUCLEI
NUCLEON REACTIONS
ODD-ODD NUCLEI
PROTON REACTIONS
R PROCESS
RADIOISOTOPES
REACTION KINETICS
SECONDS LIVING RADIOISOTOPES
SODIUM 20
SODIUM ISOTOPES
STAR BURNING
STAR EVOLUTION
STARS
TARGETS
TRANSFER REACTIONS
TRITONS
VARIABLE STARS