Charge distribution of photofission products of $^{232}\mathrm{Th}$ and $^{238}\mathrm{U}$

N. A. Demekhina ; G. S. Karapetyan

Proceedings of the Yerevan State University. Physical and mathematical sciences, no. 3 (2007), pp. 62-71.

Résumé

The $^{232}\mathrm{Th}$ and $^{238}\mathrm{U}$ photofission yields were measured by using bremsstrahlung at end-point energy of $50$ and $3500$ MeV. The nuclear charge distributions of the fission fragments were investigated and necessary parameters were determined: the most probable charge ($Z_p$) and the width parameter ($C$). The obtained data were compared with accounts on models $\mathrm{UCD}$ and $\mathrm{MPE}$. The universal picture of fission processes with different particles was confirmed.

Bibliographie

[1] E. Jacobs, H. Thierens, A. De Clercq et al., “Neutron emission in the photofission of $\mathrm{^{235}U}$ and $\mathrm {^{238}U}$ with $25~MeV$ bremsstrahlung”, Phys. Rev.C, 14 (1976), 1874 | DOI

[2] C. J. Bishop, R. Vandenbosch et al., “Excitation energy dependence of neutron yields and fragment kinetic energy release in the proton induced fission of $\mathrm{^{235}U}$ and $\mathrm{^{238}U}$”, Nucl. Phys. A, 150 (1970), 129 | DOI

[3] M. Strecker, R. Wien et al., “Prescission and postscission neutrons from the reactions $p+\mathrm{^{235,236,238}U}$ with $E_p\leq25.6~MeV$”, Phys. Rev. C, 41 (1990), 2172 | DOI

[4] F.-J. Hambsch, S. Oberstedt, G. Vladuca, A. Tudora et al., “Prompt fission neutron multiplicity and spectra evaluation in the frame of the multi-modal fission model for $\mathrm{^{237}Np}(n,f)$ and$\mathrm{^{238}U}(n,f)$”, Nucl. Phys. A, 709 (2002), 85 | DOI

[5] Chien Chung, James J. Hogan, “Fission of $\mathrm{^{232} Th}$ at energies up to $90~ MeV$”, Phys. Rev. C, 24 (1981), 180 | DOI

[6] Chung Chien, J. J. Hogan, “$\mathrm{^{238}U}$ fission at energies up to 100 MeV”, Phys. Rev. C, 25 (1982), 899 | DOI

[7] D. R. Nethaway, B. Mendoza, “Comparison of Yields from Fission of $\mathrm{^{233}U, ^{234}U, ^{235}U, ^{236}U}$ and $\mathrm {^{238}U}$ with $14.8~MeV$ Neutrons”, Phys. Rev. C, 6 (1972), 1827 | DOI

[8] V. A. Rubchenya “Prompt fission neutron emission in neutron and proton induced reactions at intermediate energies”, Phys. Rev.C, 75 (2007), 54601 | DOI

[9] V. A. Rubchenya, J. Aystö “Production of neutron rich isotopes in fission. A study for RNB facilities”, Nucl. Phys. A, 701 (2002), 127 | DOI

[10] I. Tsekhanovich, N. Varapai, V. A. Rubchenya et al., “Fission-product formation in the thermal-neutron-induced fission of odd $\mathrm{Cm}$ isotopes”, Phys. Rev. C, 70 (2004), 44610 | DOI

[11] T. Ethvignot, M. Delvin, H. Duarte et al., “Neutron Multiplicity in the Fission of $\mathrm{^{238} U}$ and $\mathrm{^{235} U}$ with Neutrons up to $200~ MeV$”, Phys. Rev. Lett., 94 (2005), 52701 | DOI

[12] Yu. Gangrskii, B. Markov, V. Perelygin, Registratsiya i spektrometriya oskolkov deleniya, Energoatomizdat, M., 1992

[13] N. A. Demekhina, G. S. Karapetyan, “Simmetrichnye i assimetrichnye mody fotodeleniya $^{232}\mathrm{Th}$ pri promezhutochnykh energiyakh”, Uch. zapiski EGU, ser. Fizika i Matematika, 2007, no. 2, 72–78

[14] G.S. Karapetyan, “Opredelenie vykhodov fotoyadernykh reaktsii metodom navedennoi aktivnosti”, Uch. zapiski EGU, ser. Fizika i Matematika, 2006, no. 3, 31–35

[15] E. Jacobs, H. Thierens, D. De Frenne et al., “Product yields for the photofission of $\mathrm{^{238} U}$ with $12-, 15-, 20-, 30-$ and $70~MeV$ bremsstrahlung”, Phys. Rev. C, 19 (1979), 422 | DOI

[16] H. Kudo, M. Maruyama, M. Tanikawa et al., “Most probable charge of fission products in $24~ MeV$ proton induced fission of $\mathrm{^{238} U}$”, Phys. Rev. C, 57 (1998), 178 | DOI

[17] H. Kudo, H. Muramatsu, H. Nakahara et al., “Fission fragment yields in the fission of $\mathrm{^{232} Th}$ by protons of energies $8$ to $22~ MeV$”, Phys. Rev. C, 25 (1982), 3011 | DOI

[18] P. David, J. Debrus, U. Kim et al., “High-energy photofission of gold and uranium”, Nucl. Phys. A, 197 (1972), 163 | DOI

[19] B. Schrøder, G. Nydahl, B. Forkman, “High-energy photofission in $\mathrm{^{238}U}$, $\mathrm{^{232}Th}$ and $\mathrm{^{209}Bi}$”, Nucl. Phys. A, 143 (1970), 449 | DOI

[20] B. Schrøder et al., “Photon-induced nuclear reactions above $1~ GeV$: (IV). Mass distribution in the $6.00~ GeV$ bremsstrahlung-induced fission of natural uranium”, Nucl. Phys. A, 197 (1972), 88 | DOI

[21] J. A. McHugh, M. C. Michel, “Fission-Fragment Mass and Charge Distribution for the Moderately Excited $\mathrm{^{236} U}$ Compound Nucleus”, Phys. Rev., 172 (1968), 1160 | DOI

[22] A. C. Wahl et al., “Nuclear-Charge Distribution in Low-Energy Fission”, Phys. Rev., 126 (1963), 1112 | DOI

[23] S. A. Rao, “Charge Distribution in the Fission of $\mathrm{^{232} Th}$”, Phys. Rev. C, 5 (1972), 171 | DOI

[24] E. Jacobs, H. Thierens, D. De Frenne et al., “Product yields for the photofission of $\mathrm{^{235} U}$ with $12-, 15-, 20-, 30-$ and $70~MeV$ bremsstrahlung”, Phys. Rev. C, 21 (1980), 237 | DOI

[25] R. H. Goeckermann, I. Perlman, “High Energy Induced Fission of Bismuth and Lead”, Phys. Rev., 76 (1949), 628 | DOI

[26] A. S. Pappas, Proceedings of the International Conference on the Peaceful Uses of Atomic Energy (Geneva, 1955), P/881