Coupled Reaction Channels Calculations
www.fresco.org.uk
 

Computer Program FRESCO

Ross Barnett's
Coulomb and Bessel functions

• APP23.TEX, APP23.dvi, APP23.pdf (macro MULTIP.CMM):
  "The Calculation of Spherical Bessel and Coulomb Functions" -- Chapter 9 of Computational Atomic Physics ed. K Bartschat.

Code

• COUL90.FOR: the subroutine

Simple driver program

• COUL90_S.FOR: driver program
• COULSMPL.IN: input
• COULSMPL.REF: reference output
• COULSMPL.OUT: computed output

Full driver program

• COUL90_T.FOR: driver program
• COULTEST.IN: input
• COULTEST.REF: reference output
• COULTEST.OUT: computed output

Bessel functions

• RICBES.FOR: real Riccati-Bessels
• SBESJY.FOR: real spherical Bessels

Complete package:

• coulombs.tar.gz

Details:

README-COUL : comments on the test files. last changed 7/7/95 (ARB)

These are FORTRAN 77 files for COUL90.FOR, SBESJY.FOR and RICBES.FOR Coulomb functions, spherical Bessel functions and Riccati-Bessel functions.
(The '90' refers to a year NOT to FORTRAN 90)

The subroutine COUL90 calculates Coulomb and spherical/cylindrical Bessels.
The other two subroutines are special cases.

Simple version:

The driver program COUL90_S.FOR calls the test file COULSMPL.IN and creates the output file COULSMPL.OUT which should be identical to COULSMPL.REF

The 1st line of input is text.
Each line then contains : eta, x, xm, lrange, kfn in format 3F10.3 , 2I5
xm is the minimum L-value desired (usually zero)
lrange is the number of additional L-values desired
kfn = 0 gives Coulomb functions
kfn = 1 gives spherical Bessel functions
kfn = 2 gives cylindrical Bessel functions
Where appropriate, calls to SBESJY and RICBES are also made.

Full test version:

The driver program COUL90_T.FOR calls the test file COULTEST.IN and creates the output file COULTEST.OUT which should be identical to COULTEST.REF

The 4-letter key words are COUL SBES BESS and BESI and signify the functions to be calculated, BESS being cylindrical Bessels and BESI being fractional order cylindrical Bessels.

NX is the number of x-values for the given orders.
NL is the number of orders for the given x-values.

The 1st line of input is text.
Each 3 [or 4] lines then contains :
CHFN, NL, NX, eta, xm in format 1X, A4, 7X, 2I3, 2F10.2
CHFN a 4-letter key word as above
NL integer L-values in free format
NX real x-values in free format
[text to annotate the output] if NX is negative

xm is the minimum L-value desired (usually zero)
lrange is the number of additional L-values desired
kfn = 0 gives Coulomb functions
kfn = 1 gives spherical Bessel functions
kfn = 2 gives cylindrical Bessel functions
Where appropriate, calls to SBESJY and RICBES are also made.

The complete description of the programs is to be found in Chapter 9 of Computational Atomic Physics ed. K Bartschat, which is called The Calculation of Spherical Bessel and Coulomb Functions by A R Barnett.