add_analytical_E_p Subroutine

  subroutine add_analytical_E_p(params,tt,F,E_PHI,Y_R,Y_Z)

    TYPE(KORC_PARAMS), INTENT(INOUT)                              :: params
    TYPE(FIELDS), INTENT(IN)                                   :: F
    INTEGER(ip),INTENT(IN)  :: tt
    REAL(rp)  :: E_dyn,E_pulse,E_width,time,arg,arg1,R0,Z0,a
    REAL(rp),DIMENSION(params%pchunk),INTENT(INOUT) :: E_PHI
    REAL(rp),DIMENSION(params%pchunk),INTENT(IN) :: Y_R,Y_Z
    REAL(rp),DIMENSION(params%pchunk) :: rm,r_a
    integer(ip) :: cc,pchunk

    pchunk=params%pchunk

    SELECT CASE (TRIM(F%E_profile))
    CASE('D3D_LOOP')

       time=params%init_time+(params%it-1+tt)*params%dt

       E_dyn=F%E_dyn
       E_pulse=F%E_pulse
       E_width=F%E_width
       R0=F%Ro

       !write(output_unit_write,*) E_dyn,E_pulse,E_width,R0

       !$OMP SIMD
       !    !$OMP& aligned(E_PHI)
       do cc=1_idef,pchunk

          arg=(time-E_pulse)**2/(2._rp*E_width**2)
          arg1=10._rp*(time-E_pulse)/(sqrt(2._rp)*E_width)

          E_PHI(cc)=E_PHI(cc)+R0*E_dyn/Y_R(cc)*exp(-arg)*(1._rp+erf(-arg1))/2._rp
       end do
       !$OMP END SIMD
    CASE('MST_FSA')

       R0=F%AB%Ro
       Z0=F%Zo
       a=F%AB%a
       E_dyn=F%E_dyn
       
       !$OMP SIMD
       do cc=1_idef,pchunk

          !write(6,*) 'E_dyn',E_dyn,'E_PHI_in',E_PHI(cc)
          
          rm(cc)=sqrt((Y_R(cc)-R0)**2+(Y_Z(cc)-Z0)**2)
          r_a(cc)=rm(cc)/a
          E_PHI(cc) = E_PHI(cc)+E_dyn-sign((2._rp*r_a(cc)**3._rp- &
               3._rp*r_a(cc)**2._rp+1._rp)*0.05/params%cpp%Eo,E_dyn)

          !write(6,*) 'r/a',r_a,'E_PHI_out',E_PHI(cc)
          
       end do
       !$OMP END SIMD
    CASE DEFAULT
       E_PHI(cc)=E_PHI(cc)
    END SELECT
    
    !write(output_unit_write,*) arg,arg1

  end subroutine add_analytical_E_p