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Title: Photon-induced multiple particle emissions of {sup 90}Zr and {sup nat}Zr from 10 to 140 MeV

Abstract

A comprehensive analysis of electrodisintegration yields of protons on {sup 90}Zr is proposed taking into account the giant dipole resonance, isovector giant quadrupole resonance (IVGQR), and quasideuteron contributions to the total photoabsorption cross section from 10 to 140 MeV. The calculation applies the MCMC intranuclear cascade to address the direct and pre-equilibrium emissions and another Monte Carlo-based algorithm to describe the evaporation step. The final results of the total photoabsorption cross section for {sup 90}Zr and relevant decay channels are obtained by fitting the (e,p) measurements from the National Bureau of Standards and show that multiple proton emissions dominate the photonuclear reactions at higher energies. These results provide a consistent explanation for the exotic and steady increase of the (e,p) yield and also a strong evidence of a IVGQR with a strength parameter compatible with the E2 energy-weighted sum rule. The inclusive photoneutron cross sections for {sup 90}Zr and {sup nat}Zr, derived from these results and normalized with the (e,p) data, are in agreement within 10% with both Livermore and Saclay data up to 140 MeV.

Authors:
; ; ;  [1];  [2];  [1];  [3];  [4]
  1. Instituto de Fisica da Universidade de Sao Paulo, P. O. Box 66318, CEP 05315-970, Sao Paulo (Brazil)
  2. Instituto de Biociencias, Universidade Estadual de Sao Paulo, Botucatu (Brazil)
  3. (CEADEN), Havana (Cuba)
  4. Universidade Estadual de Santa Cruz, Ilheus (Brazil)
Publication Date:
OSTI Identifier:
20990961
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevC.75.014605; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ALGORITHMS; CROSS SECTIONS; EMISSION; ISOVECTORS; MEV RANGE; MONTE CARLO METHOD; NUCLEAR CASCADES; PHOTONS; PHOTONUCLEAR REACTIONS; PROTONS; SUM RULES; US NBS; ZIRCONIUM 90

Citation Formats

Rodrigues, T. E., Martins, M. N., Garcia, C., Arruda-Neto, J. D. T., Mesa, J., Shtejer, K., Center of Applied Studies for Nuclear Developments, and Garcia, F. Photon-induced multiple particle emissions of {sup 90}Zr and {sup nat}Zr from 10 to 140 MeV. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.014605.
Rodrigues, T. E., Martins, M. N., Garcia, C., Arruda-Neto, J. D. T., Mesa, J., Shtejer, K., Center of Applied Studies for Nuclear Developments, & Garcia, F. Photon-induced multiple particle emissions of {sup 90}Zr and {sup nat}Zr from 10 to 140 MeV. United States. doi:10.1103/PHYSREVC.75.014605.
Rodrigues, T. E., Martins, M. N., Garcia, C., Arruda-Neto, J. D. T., Mesa, J., Shtejer, K., Center of Applied Studies for Nuclear Developments, and Garcia, F. Mon . "Photon-induced multiple particle emissions of {sup 90}Zr and {sup nat}Zr from 10 to 140 MeV". United States. doi:10.1103/PHYSREVC.75.014605.
@article{osti_20990961,
title = {Photon-induced multiple particle emissions of {sup 90}Zr and {sup nat}Zr from 10 to 140 MeV},
author = {Rodrigues, T. E. and Martins, M. N. and Garcia, C. and Arruda-Neto, J. D. T. and Mesa, J. and Shtejer, K. and Center of Applied Studies for Nuclear Developments and Garcia, F.},
abstractNote = {A comprehensive analysis of electrodisintegration yields of protons on {sup 90}Zr is proposed taking into account the giant dipole resonance, isovector giant quadrupole resonance (IVGQR), and quasideuteron contributions to the total photoabsorption cross section from 10 to 140 MeV. The calculation applies the MCMC intranuclear cascade to address the direct and pre-equilibrium emissions and another Monte Carlo-based algorithm to describe the evaporation step. The final results of the total photoabsorption cross section for {sup 90}Zr and relevant decay channels are obtained by fitting the (e,p) measurements from the National Bureau of Standards and show that multiple proton emissions dominate the photonuclear reactions at higher energies. These results provide a consistent explanation for the exotic and steady increase of the (e,p) yield and also a strong evidence of a IVGQR with a strength parameter compatible with the E2 energy-weighted sum rule. The inclusive photoneutron cross sections for {sup 90}Zr and {sup nat}Zr, derived from these results and normalized with the (e,p) data, are in agreement within 10% with both Livermore and Saclay data up to 140 MeV.},
doi = {10.1103/PHYSREVC.75.014605},
journal = {Physical Review. C, Nuclear Physics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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