Structure of Ne-18 and the breakout from the hot CNO cycle

被引:84
作者
Hahn, KI
Garcia, A
Adelberger, EG
Magnus, PV
Bacher, AD
Bateman, N
Berg, GPA
Blackmon, JC
Champagne, AE
Davis, B
Howard, AJ
Liu, J
Lund, B
Mao, ZQ
Markoff, DM
Parker, PD
Smith, MS
Stephenson, EJ
Swartz, KB
Utku, S
Vogelaar, RB
Yildiz, K
机构
[1] YALE UNIV, WRIGHT NUCL STRUCT LAB, NEW HAVEN, CT 06520 USA
[2] UNIV WASHINGTON, NUCL PHYS LAB GL10, SEATTLE, WA 98195 USA
[3] UNIV NOTRE DAME, DEPT PHYS, NOTRE DAME, IN 46556 USA
[4] INDIANA UNIV, CYCLOTRON FACIL, BLOOMINGTON, IN 47408 USA
[5] UNIV S CAROLINA, DEPT PHYS & ASTRON, CHAPEL HILL, NC 27599 USA
[6] DUKE UNIV, TRIANGLE UNIV NUCL LAB, DURHAM, NC 27706 USA
[7] PRINCETON UNIV, DEPT PHYS, PRINCETON, NJ 08544 USA
来源
PHYSICAL REVIEW C | 1996年 / 54卷 / 04期
关键词
D O I
10.1103/PhysRevC.54.1999
中图分类号
O57 [原子核物理学、高能物理学];
学科分类号
070202 ;
摘要
We used the O-16(He-3,n)Ne-18, C-12(C-12,He-6)Ne-18, and Ne-20(p,t)Ne-18 reactions to study Ne-18 states up to an excitation energy of 10 MeV, with emphasis on levels corresponding to O-14(alpha,p)F-17 and F-17(p,gamma)Ne-18 resonances that could strongly affect these reaction rates in hot stellar environments. Excitation energies, widths, absolute cross sections, and angular distributions were measured. We found previously unidentified states at E(x) = 6.15 +/- 0.01 MeV, 7.12 +/- 0.02 MeV, 7.35 +/- 0.02 MeV, 7.62 +/- 0.02 MeV, 8.30 +/- 0.02 MeV, (8.45 +/- 0.03 MeV), 8.55 +/- 0.03 MeV, 8.94 +/- 0.02 MeV, and 9.58 +/- 0.02 MeV. We combined level width, cross section, and angular distribution data to infer J(pi) values for a number of the new levels as well as for the previously known 5.1-MeV doublet. Using information from our experiments, we recalculated the O-14(alpha,p) F-17 reaction rate, which constitutes a possible path out of the hot CNO cycle into the rp process and could play an important role in transforming nuclei involved in the hot CNO cycle into heavier nuclei with Z greater than or equal to 10.
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页码:1999 / 2013
页数:15
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