Skip to main content

Precise measurement of the 7be(p,y)8b reaction cross section over a broad energy range - 100 kev to 8 mev


Research objectives and content The scope of the proposed project is to make a precise measurement of the 7Be(p,(y))8B reaction cross section, using the same detection set-up and measuring procedures over a broad energy range (100 keV - 8 MeV). For such experiments, the 4MV Tandem and the 400 kV and 100 kV electrostatic accelerators at Bochum, offer an unique opportunity. For these measurements, 7Be (T,,2 = 53 d) targets have to be produced, purified and characterised. The aim is also to develop a novel detection set-up (high efficiency). The 7Be(p,(y))8B reaction is very important with respect to the called 'solar neutrino problem'. The main source of the high-energy solar neutrinos is the beta+ decay of 8B. At present, the neutrino detectors on earth measure a flux of high-energy neutrinos considerable smaller than predicted by the Standard Solar Model. The lack, systematic measurements of the 7Be(p,(y))8B reaction over a broad energy range prohibits a reliable determination of the high-energy solar neutrino production race in the sun Training content (objective, benefit and expected impact) Objective: Production characterisation and optimisation of thin radioactive 7Be targets (T1/2 = 53.3 d). The development of detection methods for the measurement of very low reaction rates and the use of high-intensity accelerators. The use of detailed analysis procedures to determine low-energy astrophysical S-factors, using the latest theoretical models. -Benefit: development of a large number of skills related to the production of radioactive targets (handling, safety aspects characterisation, etc.), the use of low energy, high-intensity electrostatic accelerators and the measurement of very lo reaction cross sections (nb) using advanced detection techniques. -Expected impact: Such an effective training would widen my competence in experimental nuclear physics and would definitely have a strong influence on my future career as a researcher. Links with industry / industrial relevance (22) Low-energy electrostatic accelerators are used for the study of materials (e.g. thin films) using different techniques, (RBS,NRA,...). Applications also exist to use 7Be as a probe for material research, especially for wearing (deterioration) studies of plastics.


Ruhr-Universität Bochum
Universitätsstraße 150
44780 Bochum