p_cx_2 Function

  1. atomic_tables.f90
  2. atomic_tables
  3. p_cx_2

public function p_cx_2(Erel, m_max) result(sigma)

Calculates an array of cross sections for proton-Hydrogen charge exchange interactions from the state to m = 1..m_max states at energy Erel

Equation

References

Arguments

Type IntentOptional AttributesName
real(kind=Float64), intent(in) :: Erel

Relative collision energy [keV/amu]
integer, intent(in) :: m_max

Number of m states to calculate

Return Value real(kind=Float64), dimension(m_max)

Array of cross sections where the index refers to the m'th state []


Calls

proc~~p_cx_2~~CallsGraph proc~p_cx_2 p_cx_2 proc~p_cx_janev p_cx_janev proc~p_cx_2->proc~p_cx_janev proc~m_spread m_spread proc~p_cx_2->proc~m_spread proc~p_cx_1_2_adas p_cx_1_2_adas proc~p_cx_2->proc~p_cx_1_2_adas proc~p_cx_2_3_adas p_cx_2_3_adas proc~p_cx_2->proc~p_cx_2_3_adas proc~p_cx_2_2_adas p_cx_2_2_adas proc~p_cx_2->proc~p_cx_2_2_adas proc~p_cx_n_janev p_cx_n_janev proc~p_cx_janev->proc~p_cx_n_janev proc~p_cx_1_janev p_cx_1_janev proc~p_cx_janev->proc~p_cx_1_janev proc~p_cx_3_janev p_cx_3_janev proc~p_cx_janev->proc~p_cx_3_janev proc~p_cx_2_janev p_cx_2_janev proc~p_cx_janev->proc~p_cx_2_janev

Called by

proc~~p_cx_2~~CalledByGraph proc~p_cx_2 p_cx_2 proc~p_cx_n p_cx_n proc~p_cx_n->proc~p_cx_2 proc~p_cx p_cx proc~p_cx->proc~p_cx_n proc~p_cx_n_m p_cx_n_m proc~p_cx_n_m->proc~p_cx_n proc~write_bb_h_h write_bb_H_H proc~write_bb_h_h->proc~p_cx program~generate_tables generate_tables program~generate_tables->proc~write_bb_h_h

Contents

Source Code

p_cx_2

Source Code

function p_cx_2(Erel,m_max) result(sigma)
    !+Calculates an array of cross sections for proton-Hydrogen charge exchange interactions
    !+from the \(n=2\) state to m = 1..`m_max` states at energy `Erel`
    !+
    !+@note
    !+Cross sections are normalized to the total cross sections calculated by
    !+[[p_cx_janev(proc)]].
    !+
    !+@note
    !+Cross sections for the \(n=2 \rightarrow m=1\) states are calculated via
    !+equivalence principle using [[p_cx_1_2_adas(proc)]].
    !+
    !+@note
    !+Cross Sections for \(m \geq 4\) are calculated by "spreading" their
    !+expected total cross sections among the \(m \geq 4\) states.
    !+
    !+###Equation
    !+ $$H^+ + H(2) \rightarrow H(m=1..m_{max}) + H^+$$
    !+###References
    !+* Ref. 4 [[atomic_tables(module)]]
    real(Float64), intent(in)       :: Erel
        !+ Relative collision energy [keV/amu]
    integer, intent(in)             :: m_max
        !+ Number of `m` states to calculate
    real(Float64), dimension(m_max) :: sigma
        !+ Array of cross sections where the index refers to the `m`'th state [\(cm^2\)]

    real(Float64), parameter :: n2 = 4.d0
    integer :: i
    real(Float64) :: En, Em, sigma_n, norm_fac

    sigma = 0.d0
    do i=1,min(m_max,3)
        select case (i)
            case (1)
                sigma(1) = p_cx_1_2_adas(Erel*n2)/n2
            case (2)
                sigma(2) = p_cx_2_2_adas(Erel)
            case (3)
                sigma(3) = p_cx_2_3_adas(Erel)
        end select
    enddo
    sigma_n = max(p_cx_janev(Erel, 2) - sum(sigma), 0.d0)

    call m_spread(2,m_max,sigma_n,sigma)

    norm_fac = p_cx_janev(Erel, 2)/sum(sigma)
    sigma = sigma*norm_fac

end function p_cx_2