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تسجيل مستخدم جديدتحليل الطيفي ل 24Al واستخراج قوى Gamow-Teller مع تفاعل 24Mg(3He,t) في 420 ميقا فولت
Spectroscopy of 24Al and extraction of Gamow-Teller strengths with the 24Mg(3He,t) reaction at 420 MeV
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تم الدراسة للتفاعل 24Mg(3He,t)24Al عند E(3He)=420 MeV. تم الحصول على دقة انطلاقية بقيمة 35 كيلو فولت. يتم استخراج قوى Gamow-Teller لمستويات معينة في 24Al باستخدام علاقة تجريبية حديثة للتناسب بين قوى Gamow-Teller وخطوط الانحدار المختلطة في نقطة صفر لنقل الحزمة. إلا أنه تم العثور على اختلافات صغيرة لبعض التثاقلات الضعيفة، تم الحصول على اتفاق جيد مع بيانات 24Mg(p,n) السابقة والحسابات الهيكلية للنووية التي تستخدم التفاعلات USDA/B في مساحة النموذج الصحافي sd. تم قياس انطلاقية التثاقل لعدد من المستويات في 24Al التي تؤثر على تحديد معدل التفاعل 23Mg(p,gamma)24Al الحراري. وتظهر النتائج متطابقة مع اثنين من التفاعلات الثالثة (3He,t) التي تم تنفيذها في طاقات حزمة أقل بكثير. ومع ذلك، تم العثور على وضعية جديدة عند Ex(24Al)=2.605(10) MeV وهي الوضعية الثالثة أعلى من انطلاقية فصل البروتون.
The 24Mg(3He,t)24Al reaction has been studied at E(3He)=420 MeV. An energy resolution of 35 keV was achieved. Gamow-Teller strengths to discrete levels in 24Al are extracted by using a recently developed empirical relationship for the proportionality between Gamow-Teller strengths and differential cross sections at zero momentum transfer. Except for small discrepancies for a few weak excitations, good agreement with previous 24Mg(p,n) data and nuclear-structure calculations using the USDA/B interactions in the sd shell-model space is found. The excitation energy of several levels in 24Al of significance for determination of the 23Mg(p,gamma)24Al thermonuclear reaction rate were measured. Results are consistent with two of the three previous (3He,t) measurements, performed at much lower beam energies. However, a new state at Ex(24Al)=2.605(10) MeV was found and is the third state above the proton separation energy.
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