Adler-Adler Resonance Format


The total cross section in the Adler-Adler representation can be written in the following form:

AA Equations 1

where

AA Equations 2

In these equations, the nu values are resonance half widths (corresponding to Gamma/2 in the SLBW notation), the mu values are the resonance energies, the G values are the symmetric total parameters, the H values are the asymmetric total parameters, and the A and B values are coefficents of the background correction.

The fission and capture cross sections both use the following form:

AA Equations 3

with parameters appropriate for the desired reaction. The following quantities are defined for Adler-Adler subsections:

SPI
spin I of the target nucleus.
AP
scattering radius in units of 10-12 cm.
NLS
number of l states given.
AWRI
atomic weight ratio for this isotope.
LI
flag to indicate the kind of parameters being given: LI=1, total widths only; LI=2, fission widths only; LI=3, total and fission widths; LI=4, radiative capture widths only; LI=5, total and capture widths; LI=6, fission and capture widths; LI=7, total, fission, and capture widths.
NX
number of sets of background constants given. There are six constants per set. Each set refers to a particular cross section type. If NX=2, background constants are given for the total and capture cross sections; if NX=3, background constants are given for the total, fission, and capture cross sections.
NJS
number of J values for a particular l value.
NLJ
number of reesonance for the particular l,J sequence.
AT1,AT2,AT3,AT4,BT1,BT2
background constants for the total cross section.
AF1,AF2,AF3,AF4,BF1,BF2
background constants for the fission cross section.
AC1,AC2,AC3,AC4,BC1,BC2
background constants for the capture cross section.
DET_r
resonance energy (mu) for the r-th resonance in the total cross section for this l,J sequence.
DEF_r
resonance energy (mu) for the r-th resonance in the fission cross section for this l,J sequence.
DEC_r
resonance energy (mu) for the r-th resonance in the capture cross section for this l,J sequence.
DWT_r
value of Gamma/2 (nu) for the r-th resonance in the total cross section for this l,J sequence.
DWF_r
value of Gamma/2 (nu) for the r-th resonance in the fission cross section for this l,J sequence.
DWC_r
value of Gamma/2 (nu) for the r-th resonance in the capture cross section for this l,J sequence.
GRT_r
symmetrical total cross section parameter G for the r-th resonance in the total cross section for this l,J sequence.
GIT_r
asymmetrical total cross section parameter H for the r-th resonance in the total cross section for this l,J sequence.
GRF_r
symmetrical fission cross section parameter G for the r-th resonance in the total cross section for this l,J sequence.
GIF_r
asymmetrical fission cross section parameter H for the r-th resonance in the total cross section for this l,J sequence.
GRC_r
symmetrical capture cross section parameter G for the r-th resonance in the total cross section for this l,J sequence.
GIC_r
asymmetrical capture cross section parameter H for the r-th resonance in the total cross section for this l,J sequence.
The structure of a subsection for Adler-Adler parameters follows: 
        [MAT,2,151/SPI,AP,0,0,NLS,0] CONT
        [MAT,2,151/AWRI,0.0,LI,0,6*NX,NX/
                   AT1,AT2,AT3,AT4,BT1,BT2,
                   AF1,AF2,AF3,AF4,BF1,BF2,
                   AC1,AC2,AC3,AC4,BC1,BC2] LIST
                     (if NX=2, omit AF and BF 
                     from this record)
       
           Start loop over NLS values of L here
        [MAT,2,151/0.0,0.0,L,0,NJS,0] CONT

           Start loop over NJS values of AJ for this L here
        [MAT,2,151/AJ,0.0,0,0,12*NLJ,NLJ/
                   DET_1,DWT_1,GRT_1,GIT_1,DEF_1,DWF_1,
                   GRF_1,GIF_1,DEC_1,DWC_1,GRC_1,GIC_1,
                   DET_2,DWT_2,GRT_2,GIT_2,DEF_2,DWF_2,
                    ... for NLJ resonances ...   ] LIST

           Continue the loop over NJS values of AJ

           Continue the loop over NLS values of L

NEXT
INDEX

14 February 1998 T-2 Nuclear Information Service ryxm@lanl.gov