ADAS Subroutine ghnlv

       SUBROUTINE GHNLV(Z0,Z1,ZEFF,N,L,N1,NL2,TEV,GAMA,GAMTOT)
C-----------------------------------------------------------------------
C  PURPOSE: EVALUATES APPROXIMATE EXCITATION RATE PARAMETERS, GAMMA,
C  FROM N,L LEVELS OF HYDROGEN-LIKE AND LITHIUM-LIKE IONS TO HIGHER
C  LEVELS N1,L1 USING CLASSICAL OVERLAPS.
C
C  FOR TRANSITIONS FROM 1S,2S AND 2P APPROXIMATE FITTINGS ARE USED BASED
C  ON SAMPSON DATA.
C  FOR TRANSITIONS FROM HIGHER NL LEVELS UPWARDS A RESOLVED VARIANT
C  OF PERCIVAL-RICHARDS IS USED, WITH NUMERICAL QUADRATURES.
C  *******   H.P. SUMMERS, JET   15 JAN. 1985  ******************
C  INPUT
C      Z0=NUCLEAR CHARGE
C      Z1=ION CHARGE+1
C      ZEFF=EFFECTIVE ION CHARGE   (CF. SAMPSON ET AL.)
C      N=LOWER PRINCIPAL QUANTUM NUMBER
C      L=LOWER ANGULAR QUANTUM NUMBER
C      N1=UPPER PRINCIPAL QUANTUM NUMBER
C      NL2=MAXIMUM INCLUSIVE N FOR WHICH N WILL BE RESOLVED
C      TEV=ELECTRON TEMPERATURE (EV)
C  OUTPUT
C      GAMA(I),I=1,N1 IS VECTOR OF RATE PARAMETERS WITH L1=I-1 AND
C                        L1 THE UPPER ANGULAR QUANTUM NUMBER
C      GAMTOT = SUM OF GAMA(I),I=1,N1
C-----------------------------------------------------------------------
C	VERSION : 1.2
C	MODIFIED: Martin O'Mullane      
C       DATE    : 08-11-2004
C		  Alter nmax in gamaf() from 200 to 500. 	
C
C	VERSION  : 1.3
C	DATE     : 16-05-2007
C	MODIFIED : Allan Whiteford
C                  Updated comments as part of subroutine documentation
C                  procedure.
C-------------------------------------------------------------------------
       IMPLICIT REAL*8(A-H,O-Z)
      INTEGER             L,           N,           N1,          NL2
      REAL*8              GAMA(20),    GAMTOT,      TEV,         Z0
      REAL*8              Z1,          ZEFF