OKIMURA, H.H.SILVEIRA, M.A.G. daMEDINA, N.H.ZAMBONI, C.B.2014-11-192014-11-192015-04-012014-11-192014-11-192015-04-01OKIMURA, H.H.; SILVEIRA, M.A.G. da; MEDINA, N.H.; ZAMBONI, C.B. Neutron activation analysis lifetimes. In: REUNIAO DE TRABALHO SOBRE FISICA NUCLEAR NO BRASIL, 33., 7-11 de setembro, 2010, Campos do Jordao, SP. <b>Resumos...</b> p. 38. Disponível em: http://repositorio.ipen.br/handle/123456789/21218.http://repositorio.ipen.br/handle/123456789/21218Lifetime measurements are very important to study beta and gamma decay properties and are also important to identify and quantify nuclides using the parametric Neutron Activation Analysis (NAA)[1]. Beta decay lifetime affects for example the path of r-process in stellar nucleosynthesis. In this work NAA technique was applied to determine beta decay lifetime of isotopes produced at the IEA-R1 nuclear reactor at the IPEN facilities. We have used a standard reference material supplied by the IAEA (soil-7, 2709 and 2710) and NIST (8414, 1486, 1400, 1573a and 1577b) to produce short (minutes) and long-lived (hours to days) isotopes. After the irradiation, the activated samples are gamma-counted using a HPGe Spectrometer of High Energy Resolution and the gamma-ray peaks, corresponding to gamma transitions, related to the nuclides of interest, are evaluated using in-house software. The peak areas from the identified isotopes were tracked from one, five and ten minutes spectra for the short-lived element measurements and thirty and sixty minute gamma-ray spectra in order to extract the long-lived elements. We have measured the lifetimes for the isotopes 28Al,52V, 24Na, 42K, 56Mn and 140La. The lifetime results were compared with the known values from literature [1] and we have succeeded to improve the measurements for these beta-decay lifetimes.38openAccessaluminium 28aluminiumbeta decay radioisotopesbeta decaycosmochemistrydays living radioisotopeshalf-lifeheavy ion spectrometersiear-1 reactorlanthanum 140lanthanumlifetimemanganese 56neutron activation analysisnucleosynthesisparticle widthspotassium 42sodium 24vanadium 52Resumo de eventos científicoshttps://orcid.org/0000-0001-7766-2692