22Ne(α,n)25Mg:: The key neutron source in massive stars -: art. no. 202501

被引：146

作者：

Jaeger, M ^{[1
]}

Kunz, R

Mayer, A

Hammer, JW

Staudt, G

Kratz, KL

Pfeiffer, B

机构：

[1] Univ Stuttgart, Inst Strahlenphys, D-70550 Stuttgart, Germany

[2] Univ Tubingen, Inst Phys, D-72076 Tubingen, Germany

[3] Univ Mainz, Inst Kernchem, D-55128 Mainz, Germany

来源：

PHYSICAL REVIEW LETTERS | 2001年 / 87卷 / 20期

关键词：

D O I：

10.1103/PhysRevLett.87.202501

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The excitation function of the reaction Ne-22(alpha, n)Mg-25, the key neutron source in the astrophysical s process in massive stars, has been determined from threshold at E-alpha = 570 up to 1450 keV with an experimental sensitivity of 10(-11) b. For all resonances in this energy range new resonance parameters have been measured. For a possible resonance at about 635 keV a new upper limit omega gamma < 60 neV for the strength was obtained. Based on the new data, improved reaction rates were calculated as a function of temperature. The new uncertainty limits are considerably smaller than in previous determinations, ruling out the large enhancement factors, up to 500, assumed in some stellar model calculations.

引用

页码：1 / 202501

页数：4

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