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Manuscript Title: Computation of total, differential, and double-differential cross sections for compound nuclear reactions of the type (a,b), (a,bgamma) and (a,bgamma-gamma) (II) Generalized programs MANDY and BARBARA for arbitrary angular momenta in Hauser-Feshbach-Moldauer formalism. See erratum Comp. Phys. Commun. 1(1970)224.
Authors: E. Sheldon, R.M. Strang
Program title: MANDY
Catalogue identifier: ABOA_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 1(1969)35
Programming language: Algol.
Computer: BURROUGHS B5500.
Operating system: MARK VIII.
RAM: 9K words
Word size: 48
Keywords: Nuclear physics, Reaction, Mechanism, Angular distribution, Statistical, Compound nucleus, Differential, Cross section, Total cross section, Hauser-feshbach, Satchler, Moldauer, Level-width fluctuation, Spin-parity, Multipolarity, Mixing ratio, Racah functions, Clebsch-gordan, Racah coefficient, Legendre polynomials, Transmission coefficient, Penetrability, Spin orbit coupling, Optical potential, Compound-elastic, Scattering, Inelastic scattering, Compound stripping, Spin assignments, Low energy.
Classification: 17.10.

Revision history:
Type Tit le Reference
correction 000A CORRECTION 23/04/71 See below

Nature of problem:
Evaluation of total and differential cross sections in absolute and normalized form for angular distributions in low-energy nuclear reactions of the type (a,b), (a,bgamma) or (a,bgamma-gamma) according to statistical compound-nucleus theory in j-j coupling formalism. The program represents a generalization of an earlier version in as much as the collision partners may each have arbitrary spin, mass, and relative orbital momentum; the emergent gamma-radiations may be of pure or mixed multipolarity and provision is made for arbitrarily many extra exit channels of any given spin and orbital angular momentum. Spin-orbit interaction can be taken into consideration and, at option, the calculation can be made to proceed with and/or without the Moldauer level-width fluctuation modification and to extend automatically over a permuted range of spins and parities. It has been used not only for the analysis of inelastic nucleon distributions but also for (d,p), (d,n), and (alpha,n) angular distributions.

Solution method:
Using the theoretical CN formalism of Hauser and Feshbach, Biedenharn and Rose, Satchler, and Sheldon and Van Patter, augumented at option by the Moldauer modification, the calculation proceeds via an automatic selection and tabulation of angular momenta compatible with momentum and parity conservation restrictions, and evaluates the appropriate penetrability and Racah-function product for each combination (using subroutines for the penetrability and Racah functions). A summation of these products yields the Legendre-polynomial expansion coefficients required for the evaluation of absolute and normalized differential cross sections.

Restrictions:
Except that the program has been designed to cater for statistical CN formation and decay via particle (rather than gamma-radiation) channels a,b associated with known barrier penetrabilities (derived from supplementary optical-model codes) for reasonably low orbital momenta (l<~12), there are no inherent limitations upon the complexity of the situation considered.

Running time:
A single straightforward calculation requires less than 0.5 minute, though this time may extend to about 30 minutes for multiple runs incorporating the Moldauer modification with relatively high orbital and spin angular momenta and with many extra exit channels.

CORRECTION SUMMARY
Manuscript Title: (See footnote CPC vol 2 page 278). Computation of total, differential and double-differential cross sections for compound nuclear reactions of the type (a,b), (a,bgamma) and (a,bgamma-gamma) (II) Generalized programs MANDY and BARBARA for arbitrary angular momenta in Hauser-Feshbach-Moldauer formalism. (C.P.C. 1(1969)35).
Authors: E. Sheldon, R.M. Strang
Program title: 000A CORRECTION 23/04/71
Catalogue identifier: ABOA_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 2(1971)278
Classification: 17.10.