EVALUATION OF p + 3Si CROSS SECTIONS FOR THE ENERGY RANGE 1 to 15 MeV M. B. Chadwick and P. G. Young 1 July 1997 This evaluation provides a. complete representation of the nuclear data needed for transport, damage, heating, radioactivity, and shielding applications over the incident proton energy range from 1 to.15 MeV. The evaluation utilizes MF=6, MT=5 to represent all reaction data. Production cross sections and emission spectra are given for neutrons, protons, deuterons, tritons, alpha particles, gamma rays, and all residual nuclides produced (A>5) in the reaction chains. To summarize, the ENDF sections with non-zero data above are: MF=3 MT= 2 Integral of--nuclear plus interference components of the elastic scattering cross section MT= 5 MF=6 MT= 2 Sum of binary (p,n ) and (p,x) reactions Elastic (p,p) angular distributions given as ratios of the differential nuclear-plusinterference to the integrated value. MT= 5 Production cross sections and energy-angle distributions for emission neutrons, protons, deuterons, and alphas; and spectra for gamma rays and angle-integrated residual nuclei that are stable against particle emission The evaluation is based on nuclear model calculations that have been benchmarked to. experimental data, especially for n + Si28 and p + Si28 reactions (Ch97). We use the GNASH code system (Y92), which utilizes Hauser-Feshbach statistical, preequilibrium and direct-reaction theories. Spherical optical model calculations are used to obtain particle transmission coefficients for the Hauser-Feshbach calculations, as well as for the elastic proton angular distributions. Cross sections and spectra for producing individual residual nuclei are included for reactions. The energy-angle-correlations for all outgoing particles are based on Kalbach systematic (Ka88). A, model was developed to calculate the energy distributions of all recoil nuclei in the GNASH calculations (Ch96). The recoil energy distributions are represented in the laboratory system in MT=5, MF=6, and are given as isotropic in the lab system. All other data in MT.5,MF.6 are given in the center-of-mass system. This method of representation utilizes the LCT=3 option approved at the November, 1996, CSEWG meeting. Preequilibrium corrections were performed in the course of the GNASH calculations using the exciton model of Kalbach (Ka77j Ka85), validated by comparison with calculations using Feshbach,
Kerman, ~oon~n (FKK) theory [Ch931. Discrete level data from nuclear data sheets were matched to continuum level densities using the formulation of Ignatyuk (Ig75) and pairing and shell parameters from the Cook (C67) analysis. Neutron and chargedparticle transmission coefficients were obtained from the optical potentials, as discussed below. Gamma-ray transmission coefficients were calculated using the Kopecky-Uhl model (K9). DETAILS OF THE p + S1-3 ANALYSIS The Madland global medium-energy optical potential (Ma88) was used for neutrons above 46 MeV, and the Wilmore-Hodgson (Wi64) potential was used for lower neutron energies. The Madland global medium-energy optical potential was used for protons above 28 MeV, and the Beccheti-Greenlees (Be69) potential was used for lower proton energies. In both cases the transition region to the Madland potential was chosen to approximately give continuity in the reaction cross section. For deuterons, the Perey global potential was used; for alpha particles the MacFadden (Ma66) potential was used; and for tritons the Beccheti-Greenlees (Be71) potential was used. While the above optical potentials did describe the experimental proton nonelastic cross section data fairly well, we modified the theoretical predictions slightly to better agree with the measurements, and renormalized the transmission coefficients accordingly. In addition to usingsi nonelastic proton cross section measurements, we also were guided by p+al nonelastic data, scaled by A**2/3. The Si-3 nonelastic cross section was taken by scaling.the evaluated Si-28 value by 1.47 (an A**2/3 factor). Inelastic scattering to the 2+ (2.24 MeV) and 4+ (5.95 MeV) states in 3-Si was determined using a coupled-channel ECIS [Ra72] calculation. To produce continuity in the calculated inelastic cross sections up to 15 MeV, we performed an oblate rotational band (O+, 2+, 4+) coupled channel calculation using the Madland medium energy potential (with its imaginary potential reduced by 2%, to approximately account-for the coupling). Deformation parameters were chosen, in a neutroninduced calculation, to reproduce the JENDL-3 (neutron-induced) evaluation at 2 MeV (H.KITAZAWA et al.). The resulting deformation parameters (beta-2=-o.33, beta-4=.2) were close to those used for Si-28. These same beta values were used for the proton-inelastic scattering calculations. The same preequilibrium input parameters were used as for Si- 28, which was benchmarked, indirectly, by comparing neutroninduced calculated cross sections against (n,xz) data from the Louvain group at 63 MeV, and against unpublished (n,xp) data by Haight et al. for neutrons up to 5 MeV. See our ENDF file-1 for p+28si for more details. **************** **************** **************** **************** REFERENCES [Be69]. F.D. Becchetti, Jr., and G.W. Greenlees, Phys. Rev. 182, 119 (1969). [Be71]. F.D. Becchetti, Jr., and G.W. Greenlees in i :
ll~o~arization phenomena in Nuclear Reactions~ (Ed: H.H. Barschall and W. Haeberli, The University of Wisconsin Press, 1971) p.682. [Ch93]. M. B. Chadwick and P. G. Young, Feshbach-Kerman-Koonin Analysis of 93Nb Reactions: P --> Q Transitions and Reduced Importance of Multistep Compound Emission, Phys. Rev. C 47, 2255 (1993). [Ch96]. M. B. Chadwick, P. G. Young, R. E. MacFarlane, and A. J. Koning, 11 Hi9h-Energy Nuclear Data Libraries for Accelerator Driven Technologies: Calculational Method for Heavy Recoils, Proc. of 2nd Int. Conf. on Accelerator Driven Transmutation Technology and Applications, Kalmar, Sweden, 3-7 June 1996. [Ch97]. M. B. Chadwick and P. G. Young, GNASH Calculations of n,p + Si isotopes and Benchmarking of Results in APT PROGRESS REPORT: 1 June - 1 July 1997, internal Los Alamos National Laboratory memo T-2-97/,MS-43, 7,July 1997 from R.E. MacFarlane to L. Waters. [Ma66]. L. MacFadden and G. R. Satchler, Nucl. Phys. 84, 177 (1966). [Ma88]. D.G. Madland, Recent Results in the Development of a Global Medium-Energy Nucleon-Nucleus Optical-Model Potential, Proc. OECD/NEANDC Specialist s Mtg. on Preequilibrium Nuclear Reactions, Semmering, Austria, 1-12 Feb. 1988, NEANDC-245 U (1988). [Pe63]. C. M. Perey and F. G. Perey, Phys. Rev. 132, 755 (1963). [Ra72]. J. Raynal, Optical Model and Coupled-Channels Calculations in Nuclear Physics, International Atomic Energy Agency report IAEA SMR-9/8, p. 281, Vienna (1972). [Wi64]. D. Wilmore and P. E. Hodgson, The Calculation of Neutron Cross Sections from Optical Potentials, Nucl. Phys. 55, 673 (1964). [Y921. P. G. IIComPrehens ive Theory and Use Young, E. D. Arthur, and M. B. Chadwick, Nuclear Model Calculations: Introduction of the GNASH Code, LA-12343-MS (1992). to the
psi3.la15.xsinfo Wed Sep 3 11:56:52 1998 1 143 = TARGET 1Z+A (if A=O then elemental) 11 = PROJECTILE 1z+A Nonelastic, elastic, and Production cross sections for A<5 ejectiles in barns: Energy nonelas elastic neutron proton deuteron tritcm helium3 alpha gamma. A 3.E+OO 2.12E-3.E+OO.E+OO 2.9E-3.E+OO O~OOOE+OO.E+OO 1.385E-6 2.O1lE-3 4.E+OO 9.716E-2.E+OO.E+OO 9.73E-2.E+OO.E+OO.E+OO 6.689E-5 9.715E-2 5.E+OO 3.291E-1.E+OO.E+OO 3.267E-1,,,!..E+OO.E+OO.E+OO 2.271E-3 3.394E-1 6.E+OO 6.28E-1.E+OO 2.35E-1 3.953E-1.E+OO.E+OO.E+OO 2.914E-2 5.177E-1 7.E+OO 7.566E-1.E+OO 2.656E-1 4.116E-1.E+OO.E+OO.E+OO 7.941E-2 7.792E-1 8.E+OO 8.316E-1.E+OO 2.82E-1 4.331E-1.E+OO.E+OO.E+OO 1.183E-1 1.19E+O 9.E+OO 8.728E-1.E+OO 3.138E-1 4.31E-1.E+OO.E+OO.E+OO 1.29E-1 1.227E+O 1.E+O1 8.955E-1.E+OO 3.497E-1 4.444E-1 3.222E-4.E+OO.E+OO 1.31OE-O1 1.48E+O 1.1OOE+O1 9.35E-1.E+OO 3.266E-1 4.41OE-O1 2.484E-3.E+OO.E+OO 1.334E-1 1.531E+O 1.2E+1 9.77E-1.E+OO 3.245E-1 4.625E-1 6.459E-3 8.653E-6.E+OO 1.272E-1 1.629E+O 1.3E+1 9.133E-1.E+OO 3.246E-1 5.132E-1 1.269E-2 5.314E-4.E+OO 1.268E-1 1.621E+O 1.4E+1 9.193E-1.E+OO 3.443E-1 5.748E-1 2.12E-2 1.247E-3.E+OO 1.224E-1 1.538E+O 1.5E+1 9.227E-1.E+OO 3.888E-1 6.187E-1 2.721E-2 2.246E-3.E+OO 1.155E-1 1.435E+O 1.6E+1 9.221E-1.E+OO 4.335E-1 6.532E-1 3.41E-2 2.946E-3.E+OO 1.81E-1 1.345E+O 1.7E+1 9.176E-1.E+OO 4.726E-1 6.89E-1 3.943E-2 2.874E-3.E+OO 1.12E-1 1.28E+O 1.8E+1 9.16E-O1.E+OO 5.24E-1 7.16E-1 4.52E-2 2.812E-3.E+OO 9.478E-2 1.246E+O 1.9E+1 9.9E-1.E+OO 5.152E-1 7.189E-1 4.892E-2 2.774E-3.E+OO 8.563E-2 1.235E+O 2.E+O1 8.93E-1.E+OO 5.165E-1 7.315E-1 5.57E-2 2.812E-3.E+OO 8.2E-2 1.224E+O 2.2E+1 8.67E-1.E+OO 5.58E-1 7.194E-1 5.832E-2 3.535E-3.E+OO 7.892?S-2 1.241E+O 2.4E+1 8.432E-1.E+OO 5.973E-1 6.976E-1 6.42E-2 3.83E-3.E+OO 8.21E-2 1.239E+O 2.6E+1 8.191E-1.E+OO 6.222E-1 6.68E-1 6.79E-2 4.34E-3.E+OO 1.32E-1 1.194E+O 2.8E+1 7.855E-1.E+OO 6.366E-1 6.432E-1 7.14E-O2 4.323E-3.E+OO 1.6E-1 1.148E+O 3.E+O1 7.581E-1.E+OO 6.442E-1 6.291E-1 7.355E-2 4.668E-3.E+OO 9.92E-2 1.18E+OO 3.5E+1 7.183E-1.E+OO 6.596E-1 6.42E-1 7.42E-2 5.62E-3.E+OO 1.19E-1 1.42E+O 4.E+O1 6.89E-1.E+OO 6.574E-1 6.478E-1 7.458E-2 6.319E-3.E+OO 1.21E-1 9.782E-1 4.5E+1 6.414E-1.E+OO 6.665E-1 6.527E-1 7.41OE-O2 6.636E-3.E+OO 1.165E-1 8.944E-1 5.E+O1 6.24E-1.E+OO 6.721E-1 6.544E-1 7.O1lE-2 6.972E-3.E+OO 1.151E-1 8.46E-1 5.5E+1 5.693E-1.E+OO 6.785E-1 6.559E-1 6.977E-2 7.28E-3.E+OO 1.138E-1 7.96E-1 6.E+O1 5.414E-1.E+OO 6.899E-1 6.597E-1 6.99E-2 7.953E-3.E+OO 1.23E-1 7.388E-1 6.5E+1 5.243E-1.E+OO 7.53E-1 6.753E-1 6.815E-2 8.595E-3.E+OO 1.228E-1 7.239E-1 7.E+O1 5.112E-1.E+OO 7.138E-1 6.843E-1 7.1OOE-O2 9.3E-3.E+OO 1.251E-1 6,96E-1 7.5E+1 4.988E-1.E+OO 7.338E-1 7.22E-1 6.992E-2 1.4E-2.E+OO 1.297E-1 6.741E-1 8.E+O1 4.875E-1.E+OO 7.498E-1 7.165E-1 7.15E-2 1.14E-O2.E+OO 1.383E-1 6.659E-1 8.5=+1 4.77E-1.E+OO 7.658E-1 7.282E-1 7.89E-2 1.194E-2.E+OO 1.417E-1 6.478E-1 9.E+O1 4.674E-1.E+OO 7.779E-1 7.336E-1 7.226E-2 1.281E-2.E+OO 1.452E-1 6.324E-1 9.5E+1 4.59E-1.E+OO 7.857E-1 7.434E-1 7.389E-2 1.377E-2.E+OO 1.491E-1 6.lllE-1 1.E+2 4.514E-1.E+OO 7.93E-1 7.52E-1 7.53E-2 1.474E-2.E+OO 1.59E-1 6.33E-1 1.1OOE+O2 4.391E-1.E+OO 8.132E-1 7.697E-1 7.594E-2 1.658E-2.E+OO 1.562E-1 5.842E-1 1.2E+2 4.36E-1.E+OO 8.351E-1 7.837E-1 7.869E-2 1.848E-2.E+OO 1.61E-1 5.628E-1 1.3E+2 4.261E-1.E+OO 8.558E-1 8.59E-1 8.281E-2 2.14E-O2.E+OO 1.653E-1 5.483E-1 1.4E+2 4.259E-1.E+OO 8.917E-1 8.39E-1 8.545E-2 2.389E-2.E+OO 1.728E-1 5.377E-1 1.5E+2 4.295E-1.E+OO 9.312E-1 8.73E-1 9.23E-2 2.71E-2.E+OO 1.792E-1 5.368E-1 143 = TARGET 1Z+A (if A=O then elemental) 11 = PROJECTILE 1z+A Aver. lab emission energies for A<5 ejectiles in MeV: Energy neutron proton deuteron triton helium3 alpha gamma 3.E+OO.E+OO 3.176E-3.E+OO O.OOOE+OO O.OOOE+OO l.27e-2 5.E-12 4.E+OO.E+OO 1.698E+O.E+OO.E+OO.E+OO 1.268E+O 2.255E+O 5.E+OO.E+OO 2.341E+O.E+OO.E+OO.E+OO 2.19E+OO 2.252E+O 6.E+OO 5.891E-1 2.952E+O.E+OO.E+OO.E+OO 2.95E+O 2.132E+O 7.E+OO 1.58E+O 3.499E+O.E+OO.E+OO.E+OO 3.699E+O 1.896E+O 8.E+OO 1.614E+O 3.936E+O.E+OO.E+OO.E+OO 4.37E+O 1.91OE+OO 9.E+OO 1.922E+O 4.431E+O.E+OO.E+OO.E+OO 4.869E+O 1.983E+O 1.E+O1 2.244E+O 4.824E+O 1.158E+O.E+OO.E+OO 5.299E+O 2.131E+O 1.1OOE+O1 2.561E+O 5.269E+O 2.4E+O.E+OO.E+OO 5.66E+O 2.296E+O 1.2E+1 2.818E+O 5.439E+O 2.643E+O 8.889E-1.E+OO 5.994E+O 2.453E+O 1.3E+1 3.31E+O 5.393E+O 3..169E+OO 1.783E+O.E+OO 6.191E+O 2.63E+O 1.4E+1 3.51E+O 5.389E+O 3.71E+O 2.58E+O.E+OO 6.418E+O 2.79E+O 1.5=+1 3.12E+O 5.54E+O 4.161E+.-2-.92E+OO- :OOOE+6 -.639E+OO-2.733E+O 1.6E+1 2.956E+O 5.629E+O 4.723E+O 3.355E+O.E+OO 6.819E+O 2.7E+O 1.7E+1 3.O1OE+OO 5.839E+O 5.268E+O 4.32E+O.E+OO 7.8E+O 2.635E+O 1.8E+1 3.123E+O 6.81E+O 5.797E+O 4.46E+O.E+OO 7.195E+O 2.546E+O 1.9E+1 3.282E+O 6.584E+O 6.3E+O 4.817E+O.E+OO 7.334E+O 2.441E+O 2.E+O1 3.376E+O 7.19E+OO 6.839E+O 5.4E+O.E+OO 7.529E+O 2.369E+O 2.2E+1 3.676E+O 7.675E+O 8.15E+O 5.395E+O.E+OO 7.635E+O 2.284E+O 2.4E+1 3.94E+O 8.412E+O 9.172E+O 6.217E+O.E+OO 7.61E+O 2.233E+O 2,6EtOl4.199EtO9.166E+O1.331H17.11INOO.E+OO7.544E+O2.169E+O 2.8E+1 4.451E+O 9.929E+O 1.158E+1 7.835E+O.E+OO 7.841E+O 2.186E+O 3.E+O1 4.79E+O 1.65E+1 1.28E+1 8.619E+O.E+OO 8.122E+O 2.28E+O 3.5E+1 5.64E+O 1.24E+1 1.577E+1 1.2E+1.E+OO 8.52E+O 2.27E+O
psi3.la15.xsinfo Wed Sep 3 11:56:52 1998 2 4.E+O1 6.388E+O 1.311E+1 1.92E+1 4..5OOE+O1 7.39E+O 1.427E+1 2.261E+1 5.E+O1 7.623E+O 1.537E+1 2.54E+1.5.5E+1 8.225E+O 1.634E+1 2.844E+1 6.E+O1 8.661E+O 1.711E+1 3.112E+1 6.5E+1 9.212E+O 1.798E+1 3.333E+1 7.E+O1 9.892E+O 1.88E+1 3.613E+1 7.5E+1 1.39E+1 1.957E+1 3.782E+1 8.E+O1 1.9E+1 2.22E+1 3.923E+1 8.5E+1 1.139E+1 2.98E+1 4.87E+1 9.E+O1 1.188E+1 2.182E+1 4.277E+1 9.5E+1 1.246E+1 2.251E+1 4.45E+1 1.E+2 1.33E+1 2.333E+1 4.627E+1 1.1OOE+O2 1.416E+1 2.499E+1 4.823E+1 1.2E+2 1.521E+Oi 2.674E+1 5.18E+O1 1.3E+2 1.632E+1 2.819E+1 5.365E+1 1.4E+2 1.729E+1 2.968E+1 5.41OE+O1 1.5E+2 1.823E+1 3.118E+1 5.564E+1 1.125E+1.E+OO 8.648E+O 1.25E+1.E+OO 8.877E+O 1.34E+1.E+OO 9.29E+O 1.395E+1.E+OO 9.14E+OO 1.395E+1.E+OO 9.187E+O 1.47E+1.E+OO 9.232E+O 1.47E+1.E+OO 9.267E+O 1.42E+1.E+OO 9.293E+O 1.357E+1.E+OO 9.34E+O 1.333E+1.E+OO 9.357E+O 1.39E+1.E+OO 9.391E+O 1.282E+1.E+OO 9.397E+O 1.255E+1.E+OO 9.495E+O 1.213E+1.E+OO 9.564E+O 1.178E+1.E+OO 9.654E+O 1.141E+1.E+OO 9.81OE+OO 1.19E+O1.E+OO 9.938E+O 1.86E+1.E+OO 1.7E+1 2.277E+O 2.271E+O 2.288E+O 2.279E+O 2.248E+O 2.248E+O 2.154E+O 2.15E+O 2.15E+O 2.141E+O 2.14E+O 2.124E+O 2.141E+O 2.16E+O 2.168E+O 2.184E+O 2.197E+O 2.22E+O
p+ 3Siangle-integrated emission spectra
p+ 3Si Kalbach preequilibrium ratios
f,,,,, / ọ -G L(I Of 1- CL aq) ṇ L ẓ- T
i. A CD m a -1 1- / L a q).2 4-5 a) c CG
,,,, I I 1111 u) o d- ml > c1) ccl CD. c 3 z CD c ml I I I I I I d- a co C9 d- CN