ADAS Subroutine r8necip

C
      FUNCTION R8NECIP( IZ , XI , ZETA , TE , ALFRED)
      IMPLICIT REAL*8(A-H,O-Z)
C-----------------------------------------------------------------------
C
C  **************** FORTRAN77 REAL*8 FUNCTION: R8NECIP *****************
C
C  PURPOSE: EVALUATES A SHELL CONTRIBUTION TO THE IONISATION RATE
C           COEFFICIENT IN THE ECIP APPROXIMATION, AND RETURNS
C           THE THREE-BODY RECOMBINATION COEFFICIENT IN REDUCED
C           FORM IE. OMITTING THE WEIGHTING FACTOR W(I)/W+
C
C  CF. SUMMERS (1974)APPLETON LABORATORY REPORT IM367
C
C
C  BASED UPON ADASXX20(R8NBCH) AND COPASE(RECIP2)
C
C  CALLING PROGRAM: GENERAL USE
C
C  FUNCTION:
C          (R*8)  R8NECIP = FUNCTION NAME
C          (I*4)  IZ      = TARGET ION CHARGE NUMBER
C                           (RECOMBINED ION CHARGE).
C          (R*8)  XI      = EFFECTIVE IONISATION POTENTIAL FOR SHELL
C                           (UNITS: RYDBERGS)
C                           (LEVEL ENERGY RELATIVE TO IONISATION POT.)
C          (R*8)  ZETA    = EFFECTIVE NUMBER OF EQUIVALENT ELECTRONS
C                           IN SHELL
C          (R*8)  TE      = ELECTRON TEMPERATURE (IN KELVIN)
C          (R*8)  ALFRED  = THREE-BODY COEFFICIENT*W+/W(I)  (CM**6 S-1)
C
C
C ROUTINES:
C          ROUTINE    SOURCE    BRIEF DESCRIPTION
C          -------------------------------------------------------------
C          R8YIP      ADAS      FUNCTION:
C
C
C AUTHOR:   W.J. DICKSON
C           K1/1/36
C           JET EXT. 5057
C
C DATE:     05/01/93
C
C***********************************************************************
C UNIX-IDL PORT:
C
C AUTHOR: DAVID H BROOKS, UNIVERSITY OF STRATHCLYDE
C
C DATE: UNKNOWN
C
C***********************************************************************
C PUT UNDER SCCS CONTROL:
C
C VERSION: 1.1                          DATE: 10/05/96
C MODIFIED: WILLIAM OSBORN (TESSELLA SUPPORT SERVICES PLC)
C           - FIRST PUT UNDER SCCS
C
C VERSION  : 1.2
C DATE     : 16-02-2006
C MODIFIED : Martin O'Mullane
C               - Removed mainframe listing information beyond column 72.
C
C VERSION  : 1.3
C DATE     : 20-07-2007
C MODIFIED : Allan Whiteford
C               - Small modification to comments to allow for automatic
C                 documentation preparation.
C-----------------------------------------------------------------------
      INTEGER             IZ
      REAL*8              ALFRED,      TE,          XI,          ZETA