7. UNUSUAL FEATURES OF THE PROGRAM
a. Optical model particle transmission coefficients are calculated according to a spherical optical model.
Optical model parameter sets can be given in input or selected by means of acronyms out of a library available internally to the code.
b. The correction for the width fluctuations has been introduced into channels leading both to discrete and to continuum level excitation.
c. Composite level density like Gilbert-Cameron is used but with constant in spin distribution K = .146, when not given in input. For low lying levels between Ecut and U(x), sigma(E)**2 is auto- matically interpolated between sigma(LEVELS)**2 and sigma(U(x))**2 = K.SQRT(aU(x)).exp(A,2/3). The value
sigma(LEVELS)**2 is obtained by maximum likelihood method to fit known discrete levels distribution.
Sigma(LEVELS)**2 is calculated by the code on the basis of adop- ted level for each nucleus involved. Alternatively sigma(LEVELS)**2 can also be given in input, in those particu- lar nuclei where additional information is known above Ecut, as far as spin attribution is concerned.
d. Optionally a parity distribution p(pi)=exp(AE+B) according to ref. 1 can also be assumed provided A and B are given in input.
e. Gamma-ray transmission coefficients are calculated according to one or two Lorentzian curves for the E1 photoabsorption cross sections. Peak energy, half maximum width, peak cross section must be given in input for the E1 giant resonance.
The resulting total radiative width is spin and parity depen- dent. In principle it should not be normalized because the model proved to work satisfactorily. For the purpose of evalua- tion a normalization constant N (J and pi independent) can be given in input.
f. Q values are calculated from recent mass excess tables (internal to the code) provided by Wapstra in 1978 as a private communica- tion.
g. i) The output are average resonance parameters like strength functions (from adopted optical model), radiative width and mean observed level spacing.
ii) Angular distributions are given for compound, shape and total elastic. Total cross section and primary spectra are given for all involved particle and gamma-ray emis- sions.
Compound nucleus and total cross section from optical model are given at the end together with the percentual differ- ence between compound nucleus cross section and the sum of the contribution of all channels via compound nucleus re- action mechanism.