Calculation Of Production Cross Sections Research Articles

ISICS2008: An expanded version of ISICS for calculating K-, L-, and M-shell cross sections from PWBA and ECPSSR theory

New version program summary Program title: ISICS2008 Catalogue identifier: ADDS_v4_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADDS_v4_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5420 No. of bytes in distributed program, including test data, etc.: 107 669 Distribution format: tar.gz Programming language: C Computer: 80 486 or higher level PCs Operating system: Windows XP and all earlier operating systems Classification: 16.7 Catalogue identifier of previous version: ADDS_v3_0 Journal reference of previous version: Comput. Phys. Comm. 179 (2008) 616 Does the new version supersede the previous version?: Yes Nature of problem: Ionization and X-ray production cross section calculations for ion–atom collisions. Solution method: Numerical integration of form factor using a logarithmic transform and Gaussian quadrature, plus exact integration limits. Reasons for new version: Addition of relativistic treatment of both projectile and K-shell electrons. Summary of revisions: A new addition to ISICS is the option (R) to calculate ECPSSR cross sections that account for the relativistic treatment of both projectile and K-shell electron, as proposed recently by Lapicki [1], accordingly as σ K RECPSSR = C K ⋅ ( 1 + 0.07 ( θ K ς K ) 8 ( m K R υ 1 R Z z K ) 2 ) ⋅ σ PWBA ( ( m K R υ 1 R ) / Z z K , ς K θ K ) , where υ 1 R is the relativistic projectile velocity. The option can also be invoked in calculating ECPSShsR, where hsR stands for the Hartree–Slater description of the K-shell electron, which was already incorporated into ISICS2006 [2,3], and is now expressed in this option as, σ K RECPSShsR = C K ⋅ hsR ( ( 2 υ 1 R ) / ( Z z K ς K θ K ) , Z z / 137 ) ⋅ ( 1 + 0.07 ( θ K ς K ) 8 ( υ 1 R / Z z K ) 2 ) ⋅ σ PWBA ( υ 1 R / Z z K , ς K θ K ) using the function hsR that is already incorporated into ISICS2006. It should be noted that these expressions are corrected versions [4] from the ones published in Ref. [1]. In this new version, ISICS2008, the option line in the main menu that read “Use Relativistic Proj. velocity” has been replaced by “R option for K-shell … Uses Rel. Proj. vel.”. As before, various combinations of options can be utilized and each is denoted in the output. Restrictions: The consumed CPU time increases with the atomic shell ( K , L , M ) , but execution is still very fast. Additional comments: A revised User Manual is included in the distribution file. Running time: This depends on which shell and the number of different energies to be used in the calculation. The running time is not significantly changed from the previous version. As before, to calculate K-shell cross sections for protons striking carbon for 19 different proton energies it took less than 10 s; to calculate M-shell cross sections for protons on gold for 21 proton energies it took 4.2 min.

An improved version of ISICS: A program for calculating K-, L- and M-shell cross sections from PWBA and ECPSSR theory using a personal computer

The formatting of the M-shell atomic parameters imbedded in file XCSC.H in ISICS has been corrected. The problem only affected cross section calculations for Uranium and heavier elements. The corrected version of ISICS has been re-compiled and is now available. New version program summary Program title: ISICS Catalogue identifier: ADDS_v3_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADDS_v3_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 4645 No. of bytes in distributed program, including test data, etc.: 106 731 Distribution format: tar.gz Programming language: C++ Computer: 80486 or higher-level PCs Operating system: WINDOWS 98 through WINDOWS XP Classification: 16.7 Does the new version supersede the previous version?: Yes Nature of problem: Ionization and X-ray production cross section calculations for ion-atom collisions. Solution method: Numerical integration of form factor using a logarithmic transform and Gaussian quadrature, plus exact integration limits. Reasons for new version: The formatting of the M-shell atomic parameters involving cross section calculations for Uranium and heavier elements needed to be corrected. Summary of revisions: The affected file XCSC.H in ISICS has been corrected and ISICS has been recompiled. Restrictions: The consumed CPU time increases with the atomic shell (K, L, M), but execution is still very fast. Running time: This depends on which shell and the number of different energies to be used in the calculation. For example, to calculate K-shell cross sections for protons striking carbon for 19 different proton energies it took less than 10 s; to calculate M-shell cross sections for protons on gold for 21 proton energies it took 4.2 min.

An improved version of ISICS: a program for calculating K-, L- and M-shell cross sections from PWBA and ECPSSR theory using a personal computer

The C program, ISICS [Z. Liu, S.J. Cipolla, Comput. Phys. Comm. 97 (1996) 315–330], which calculates ionization and X-ray production cross-sections using PWBA and ECPSSR theory, has been enhanced to include new options, correct some minor flaws, and to make the program more versatile. Program summary Title of program: ISICS Catalog identifier: ADDS_v2_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADDS_v2_0 Program available from: CPC Program Library, Queen's University of Belfast, N. Ireland Operating system under which the program has been tested: WINDOWS XP Program language used: C Computer: 80486 or higher-level PCs No. of lines in distributed program, including test data, etc.: 5343 No. of bytes in distributed program, including test data, etc.: 151 838 Distribution format: tar.gz Catalogue identifier of previous version: ADDS Journal reference of previous version: Comput. Phys. Comm. 97 (1996) 315–330 Does the new version supersede the previous version: Yes Nature of the physical problem: Ionization and X-ray production cross-section calculations for ion–atom collisions. Reasons for new version: Increased functionality and new options. Summary of revisions: Option for the united-atom approximation for binding-energy correction; easier inputting of updated atomic parameters; extension of projectile energy down to eV range; accounting for DHS wave function in K-shell ionization; other miscellaneous changes. Method of solution: Numerical integration of form factor using a logarithmic transform and Gaussian quadrature, plus exact integration limits. Restrictions on the complexity of the problem: The consumed CPU time increases with the atomic shell (K, L, M), but execution is still very fast. Typical running time: No change from previous version. Unusual features of the program: No

The McGNASH nuclear reaction code and its use for gas production cross-section calculations

The McGNASH nuclear reaction code being developed at Los Alamos is presented. It is a modern version of the well-known GNASH code, which implements the Hauser–Feshbach theory of the compound nucleus evaporation and takes into account corrections from the pure statistical formalism (direct reactions, pre-equilibrium processes, etc.). Its use spans neutron-, proton- and photon-induced reactions on target nuclei starting from A ≃ 20 and up, and for incident energies from tens of keV up to about 200 MeV. Its application to the determination of gas production cross-sections for the Advanced Fuel Cycle Initiative is presented.

Fusion cross sections for superheavy nuclei in the dinuclear system concept

Using the dinuclear system concept we present calculations of production cross sections for the heaviest nuclei. The obtained results are in a good agreement with the experimental data. The experimentally observed rapid fall-off of the cross sections of the cold fusion with increasing charge number Z of the compound nucleus is explained. Optimal reactions for the synthesis of the superheavy nuclei are suggested.

Xenon production cross sections at intermediate energies and production rates in small meteoroids based on simulation experiments

Thin-target production cross sections of xenon isotopes from barium were determined at proton energies of 600 MeV, 800 MeV, 1200 MeV and 2600 MeV using the CERN synchrocyclotron, LANL/Los Alamos and LNS/Saclay accelerators. The data thus obtained are compared with a priori thin-target production cross section calculations using code ALICE. Production cross sections for the neutron induced reactions are estimated theoretically. Together with the cross sections at low energies (≤45 MeV) for the p-induced reactions on barium, determined by us earlier, the present data set provides a basis for evaluating the cosmogenic xenon production rates in extraterrestrial matter. Further, the depth profiles for the production of stable xenon isotopes and 127Xe radionuclide in 5 cm, 15 cm and 25 cm artificial meteoroids, irradiated isotropically with 600 MeV protons, are determined experimentally. These measured depth profiles are compared with theoretical estimates of the xenon production rates from barium in artificial meteoroids, calculated by folding depth dependent spectra of primary protons, secondary protons and neutrons with the thin-target excitation functions for the underlying proton and neutron induced reactions. The production rates thus obtained are compared with theoretical estimates using the depth profiles of well studied radionuclide production in meteoroids of various sizes. The measured xenon production ratios in the thick targets isotropically irradiated with 600 MeV protons and the calculated xenon production ratios in artificial meteoroids irradiated with realistic GCR energy spectrum are compared with those deduced from meteorite analysis and are found to be significantly different. The possible reasons for the discrepancy are explored. The refinements that are still necessary to accurately estimate xenon production rates in extraterrestrial material are discussed.

Helium production cross sections in structural materials irradiated by protons and neutrons at energies up to 800 MeV

Abstract The proton and neutron helium production cross sections have been obtained for a number of structural materials in the energy range between 10 and 800 MeV. The cross-section calculations have been carried out using the DIDACS/90 code package and the ALICE/ASH code. Some features of high energy helium production cross-section calculations are discussed.

THE PRODUCTION OF WEAK INTERMEDIATE BOSONS IN e-p REACTIONS

The calculations of production cross sections of W’ s and Z0’ s in e-p reactions at HERA energies and beyond are revised, improved and updated. Comparison with previous calculations show that in some cases the cross sections were considerably overestimated. The effects of a possible deviation of the W anomalous magnetic moment from the standard model value are also discussed.

Close-coupled and coupled-states calculation of shear viscosity SBE cross sections for the H2–He system

Close-coupled (CC) and coupled-state (CS) calculations of kinetic theory relaxation and production cross sections are presented for the system H2 at infinite dilution in a bath of He. Performing these calculations for the same potential has allowed a test to be made of the efficacy of the CS procedure for use in calculating kinetic theory cross sections, especially those determining the Senftleben–Beenakker effects (SBE) in transport phenomena. The CS procedure is found to work extremely well (better than 1% agreement with CC results) for those cross sections that are predominantly elastic, to work rather well for relaxation cross sections determined either by reorientation of energetically inelastic collisonal events (about 10% agreement with CC results), and to work relatively poorly for production cross sections. In fact, the CS procedure for light molecules fares only marginally better than the IOS procedure for heavier molecules in the calculation of production cross sections. Finally, using only CC results, the sensitivity of the shear viscosity SBE is shown to be sufficient to distinguish easily between two recently obtained ab initio potentials for the H2–He system.