FLORES, J.P.O.SEMMLER, R.2018-03-152018-03-15FLORES, J.P.O.; SEMMLER, R. Characterization of neutron spectrum at the short irradiation facility of the IEA-R1 reactor using the bare triple monitor method. In: 60 YEARS OF IEA-R1: INTERNATIONAL WORKSHOP ON UTILIZATION OF RESEARCH REACTORS, November 28 - December 01, 2017, São Paulo, SP. <b>Abstract...</b> São Paulo, SP: Instituto de Pesquisas Energéticas e Nucleares, 2017. p. 30-30. Disponível em: http://repositorio.ipen.br/handle/123456789/28725.http://repositorio.ipen.br/handle/123456789/28725The neutron spectrum parameters were determined in the short irradiation facility of the IEA-R1 reactor of IPEN. The neutron spectrum parameters are: the epithermal neutron flux shape factor ( ) approximated by a 1=E1+ distribution and the thermal to epithermal neutron flux ratio (f ). According to the HOGDAHL formalism, the k0-NAA method uses the following input parameters: the full energy peak detection efficiency ("p), and nuclear data on Q0 (ratio of resonance integral I0 to thermal neutron cross-section 0) and k0 factors. The and f parameters depend on each irradiation facility and "p depends on each counting facility. In the HOGDAHL formalism the reactor neutron spectrum parameters ( and f ) can be obtained using three methods: Cd-ratio, Cd-covered and bare triple monitors. In this work and f were determined by the bare triple monitor method. In this method, a set of three neutron flux monitors are irradiated without Cd-cover. The efficiency curves of the gamma-ray spectrometer used were determined by measuring calibrated radioactive sources at the usually utilized counting geometries.30-30openAccessResumo de eventos científicoshttps://orcid.org/0000-0001-7733-0153