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تسجيل مستخدم جديدStudy of $boldsymbol{(alpha,p)}$ and $boldsymbol{(alpha,n)}$ reactions with a Multi-Sampling Ionization Chamber
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A large number of $(alpha,p)$ and $(alpha,n)$ reactions are known to play a fundamental role in nuclear astrophysics. This work presents a novel technique to study these reactions with the active target system MUSIC whose segmented anode allows the investigation of a large energy range of the excitation function with a single beam energy. In order to verify the method, we performed a direct measurements of the previously measured reactions $^{17}$O$(alpha,n)^{20}$Ne, $^{23}$Na$(alpha,p)^{26}$Mg, and $^{23}$Na$(alpha,n)^{26}$Al. These reactions were investigated in inverse kinematics using $^{4}$He gas in the detector to study the excitation function in the range of about 2 to 6 MeV in the center of mass. We found good agreement between the cross sections of the $^{17}$O$(alpha,n)^{20}$Ne reaction measured in this work and previous measurements. Furthermore we have successfully performed a simultaneous measurement of the $^{23}$Na$(alpha,p)^{26}$Mg and $^{23}$Na$(alpha,n)^{26}$Al reactions.
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The $^{23}$Na$(alpha,p)^{26}$Mg and $^{23}$Na$(alpha,n)^{26}$Al reactions are important for our understanding of the $^{26}$Al abundance in massive stars. The aim of this work is to report on a direct and simultaneous measurement of these astrophysic
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