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Determinação das secções eficazes das reações nucleares: 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li
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Orientador(es)
Resumo(s)
Numa era em que a produção de energia exige um novo paradigma científico e tecnológico
com o propósito de se obter energia limpa, foi iniciado o projeto ITER, que tem como
principal objetivo conceber e construir um reator de fusão nuclear para ser usado como
fonte de energia sustentável.
Devido à necessidade de avaliar o desgaste das paredes do tokamak do ITER, durante
o processo de fusão nuclear, e visto que o uso de berílio como PFC já foi confirmado, torna-
se necessário aumentar os dados disponíveis nas bases de dados das secções eficazes das
reações 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li.
Para calcular as secções eficazes foram concebidos alvos autossustentados de berílio e
prata e foram utilizadas algumas técnicas de IBA, nomeadamente RBS, EBS e NRA, com
recurso ao acelerador Tandem do LATR/CTN-IST. As secções eficazes foram calculadas
para energias entre os 1.7 MeV e os 2.6 MeV, em dois ângulos diferentes 140º e 160.5º.
Foram utilizados três métodos para a determinação das secções eficazes: dois res-
paldados na comparação direta entre as contagens da reação 9Be(p, p)9Be com a reação
Ag(p, p)Ag, e outro através da aplicação do software NDF. Foi ainda efetuado um estudo
das incertezas associadas às secções eficazes calculadas.
Os resultados obtidos neste estudo são um contributo para a compreensão das intera-
ções que ocorrem com o berílio quando utilizado como PFC pois incrementam os dados
disponíveis sobre as secções eficazes das reações 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li.
With the pressing need for renewable energy sources, the ITER project was launched to design and construct a nuclear fusion reactor as a sustainable source of energy. Due to the need to assess the wear of the ITER tokamak walls during the nuclear fusion process, and since the use of beryllium as a PFC has already been confirmed, it becomes necessary to increase the data available in the databases of the cross sections of reactions 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li. In order to calculate the cross sections were assembled self-sustained beryllium and silver targets and some IBA techniques were used, namely RBS, EBS and NRA, with the use of the Tandem accelerator at the LATR/CTN-IST. The cross sections were calculated for energies between 1.7 MeV and 2.6 MeV, at two different angles, 140º and 160.5º. Three methods were used for determining these cross sections: two based on direct comparison between the yield of the 9Be(p, p)9Be reaction and the yield of the Ag(p, p)Ag reaction, and one through the application of the NDF software. A study of the uncertain- ties associated with the calculated cross sections was also carried out. The results obtained in this study are a contribution to understanding the interactions that occur with beryllium when used as a PFC, as they increase the available data of the cross sections of the reactions 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li.
With the pressing need for renewable energy sources, the ITER project was launched to design and construct a nuclear fusion reactor as a sustainable source of energy. Due to the need to assess the wear of the ITER tokamak walls during the nuclear fusion process, and since the use of beryllium as a PFC has already been confirmed, it becomes necessary to increase the data available in the databases of the cross sections of reactions 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li. In order to calculate the cross sections were assembled self-sustained beryllium and silver targets and some IBA techniques were used, namely RBS, EBS and NRA, with the use of the Tandem accelerator at the LATR/CTN-IST. The cross sections were calculated for energies between 1.7 MeV and 2.6 MeV, at two different angles, 140º and 160.5º. Three methods were used for determining these cross sections: two based on direct comparison between the yield of the 9Be(p, p)9Be reaction and the yield of the Ag(p, p)Ag reaction, and one through the application of the NDF software. A study of the uncertain- ties associated with the calculated cross sections was also carried out. The results obtained in this study are a contribution to understanding the interactions that occur with beryllium when used as a PFC, as they increase the available data of the cross sections of the reactions 9Be(p, p)9Be, 9Be(p, d)8Be e 9Be(p, α)6Li.
Descrição
Palavras-chave
Secções eficazes 9Be Técnicas de feixe de Iões Caracterização de materiais Fusão Nuclear