The transmutation of magnesium, aluminium and silicon by deuterons

Abstract

A study has been made of the protons emitted by magnesium, aluminium and silicon targets when bombarded by deuterons of energy between 700 and 1000 keV. The Q values of these (d, p) reactions have been accurately determined. Observations of the induced radioactivity in the targets and comparisons with the Q values in analogous nuclei permit tentative assignments to the isotopes responsible. The Q values and assignments are: 24Mg (d, p) 2SMg 26Mg (d, p) 26Mg* 2®Mg (d, p) 27Mg 27A1 (d, p ) 28A1 28Si (d, p)2»Si “ Si (d, p)«Si Q = 5 03 MeV Q = 4-45 MeV (to excited state) Q = 4 05 MeV Q = 5-46 MeV = 4-46 MeVl = 3-98 MeV 1 (to excited states) = 3-31 MeV j Q = 6-16 MeV .= 4-87 MeV) .. .. , . , . = 3-75 MeV j The yield of the proton group attributed to 26 Mg (d, p ) 26 Mg* shows a resonance at 955 kV bombarding voltage, as does also the yield of radioactive 26 A1 formed in the reaction 26 Mg (d, n) 26 A1. This indicates a resonance level in the compound nucleus 27A1 at an excitation energy of 17 MeV. The maximum energy of the β+ rays from 26 A1 was measured as 2-8 MeV. The Q values listed above lead to a set of nuclear mass values, but these mass values are not always in satisfactory agreement with the published Q values for certain other reactions.