SUBROUTINE SQRTB(ZRR,sqBZ) 12,1

      IMPLICIT NONE

      include 'champ.cdk'
      include 'chobs.cdk'

      REAL      sigma,MZO,dist
      INTEGER   jdata
      EXTERNAL  KR,RK,GAUSSIAN
      COMPLEX   Z(IKTX,IKTY)
      COMPLEX   sqBZZ(IKTX,IKTY),sqBZ(IKTX,IKTY)
      REAL      BR(N,N),ZRR(N,N)

      EXTERNAL KR,RK,GAUSSIAN

      DO IW=1,N
      DO JW=1,N
         ZRR(IW,JW)=sigmab * ZRR(IW,JW)
      ENDDO
      ENDDO

      CALL RK(ZRR,sqBZZ,KTX,KTY,IKTX,IKTY,N,N2,LWRK,
     .                  FF1,FF2,FF3,WORK,TRIGS,IFAX,ZI)

      DO IW=1,IKTX
      DO JW = 1,IKTY
C         sqBZ(IW,JW) = N*sqrt(2*Ftilde(IW,JW))*sqBZZ(IW,JW)
          sqBZ(IW,JW) = sqrt(2*Ftilde(IW,JW))*sqBZZ(IW,JW)
          sqBZ(IW,JW) = L(IW+KTX,JW)*sqBZ(IW,JW)
      END DO
      END DO

      CONTINUE
      END