Delayed neutron spectra and their uncertainties in fission product summation calculations Miyazono, T; Sagisaka, M; Ohta, H; Oyamatsu, K; Tamaki, M [Nagoya Univ. (Japan)] 66 PHYSICS; DELAYED NEUTRONS; FISSION SPECTRA; FISSION YIELD; DELAYED NEUTRON PRECURSORS; AFTER-HEAT; FISSION PRODUCTS; DATA COVARIANCES; EVALUATION; DELAYED NEUTRON FRACTION; BETA-DELAYED NEUTRONS Uncertainties in delayed neutron summation calculations are evaluated with ENDF/B-VI for 50 fissioning systems. As the first step, uncertainty calculations are performed for the aggregate delayed neutron activity with the same approximate method as proposed previously for the decay heat uncertainty analyses. Typical uncertainty values are about 6-14% for {sup 238}U(F) and about 13-23% for {sup 243}Am(F) at cooling times 0.1-100 (s). These values are typically 2-3 times larger than those in decay heat at the same cooling times. For aggregate delayed neutron spectra, the uncertainties would be larger than those for the delayed neutron activity because much more information about the nuclear structure is still necessary. (author) Japan Atomic Energy Research Inst., Tokyo (Japan) OSTI as DE97758662 Japan 1997-03-01 English Conference Conference: 1996 symposium on nuclear data, Tokai (Japan), 21-22 Nov 1996; Other Information: PBD: Mar 1997; Related Information: Is Part Of Proceedings of the 1996 symposium on nuclear data; Iguchi, Tetsuo [Nagoya Univ. (Japan)]; Fukahori, Tokio [eds.]; PB: 332 p. Medium: X; Size: pp. 83-88 https://doi.org/ ON: DE97758662 [] JAERI-Conf-97-005; CONF-9611184-; INDC(JPN)-179/U Other: ON: DE97758662; TRN: JP9709087 JPN; SCA: 663470; PA: JPN-97:009087; EDB-97:147521; SN: 97001866990 2008-02-05 544674 https://www.osti.gov/etdeweb/servlets/purl/544674