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تسجيل مستخدم جديدالعامل S الفلكي للالتقاط الإشعاعي 12N(p،gamma)13O الذي تم تحديده من تفاعل النقل الإشعاعي للبروتون 14N(12N،13O)13C
Astrophysical S factor for the radiative capture 12N(p,gamma)13O determined from the 14N(12N,13O)13C proton transfer reaction
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تم التحقق من تقطع الصليب لإطلاق الذرات الشعاعية للاستيلاء على النوكليوس 12N على الخط الشريط باستخدام طريقة المعامل التقليدي الأشعاعي (ANC). استخدمنا تفاعل النقل البروتوني 14N (12N, 13O) 13C عند 12 ميجا فولت في النوكلون لاستخراج ANC لـ 13O -> 12N + p وحساب من ذلك العنصر الفلكي S لإطلاق الذرات الشعاعية للاستيلاء على 12N (p, gamma) 13O. تم مناقشة الحسابات البحثية البصرية المستخدمة وتحليل DWBA لتفاعل النقل البروتوني. للقناة الدخولية، تم تحديد الحساب البحثي البصري من التصدير المرن الذي تم إجراؤه في نفس الوقت مع القياس النقل. من النقل، تم تحديد مربع ANC، C ^ 2 (13Og.s.) = 2.53 +/- 0.30 fm-1، ومن ثم تم الحصول على قيمة 0.33 (4) كيلو فولت برم بالنسبة لعنصر الفلكي S المباشر في الصفر الطاقة. التداخل البنائي في الأطوال المنخفضة بين الاستيلاء المباشر والاستيلاء الحالي يؤدي إلى تعزيز Stotal (0) = 0.42 (5) كيلو فولت برم. تم التحقق من إطلاق الذرات الشعاعية للاستيلاء على 12N (p, gamma) 13O بشأن تطور نجوم الأكثر ثروة في الهيدروجين من الأجيال الثالثة، لدور قد يلعبه في عمليات حرق الذرات الشعاعية النووية السريعة المحتملة في هذه الكائنات.
The cross section of the radiative proton capture reaction on the drip line nucleus 12N was investigated using the Asymptotic Normalization Coefficient (ANC) method. We have used the 14N(12N,13O)13C proton transfer reaction at 12 MeV/nucleon to extract the ANC for 13O -> 12N + p and calculate from it the direct component of the astrophysical S factor of the 12N(p,gamma)13O reaction. The optical potentials used and the DWBA analysis of the proton transfer reaction are discussed. For the entrance channel, the optical potential was inferred from an elastic scattering measurement carried out at the same time with the transfer measurement. From the transfer, we determined the square of the ANC, C^2(13Og.s.) = 2.53 +/- 0.30 fm-1, and hence a value of 0.33(4) keVb was obtained for the direct astrophysical S factor at zero energy. Constructive interference at low energies between the direct and resonant captures leads to an enhancement of Stotal(0) = 0.42(5) keVb. The 12N(p,gamma)13O reaction was investigated in relation to the evolution of hydrogen-rich massive Population III stars, for the role that it may play in the hot pp-chain nuclear burning processes, possibly occurring in such objects.
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