Calculates total cross section for a proton-Hydrogen charge exchange interaction
from the state to states at energy Erel
Type | Intent | Optional | Attributes | Name | ||
---|---|---|---|---|---|---|
real(kind=Float64), | intent(in) | :: | Erel | Relative collision energy [keV/amu] |
Cross Section []
function p_cx_3_6inf_adas(Erel) result(sigma)
!+Calculates total cross section for a proton-Hydrogen charge exchange interaction
!+from the \(n=3\) state to \(\forall \; m \geq 6\) states at energy `Erel`
!+
!+###Equation
!+ $$H^+ + H(3) \rightarrow H(\forall \; m \geq 6) + H^+$$
!+###References
!+* Ref. 4 [[atomic_tables(module)]]
real(Float64), intent(in) :: Erel
!+ Relative collision energy [keV/amu]
real(Float64) :: sigma
!+ Cross Section [\(cm^2\)]
real(Float64), dimension(11), parameter :: a = [ 7.146969470d5,-1.665413326d6, &
1.735840441d6,-1.065792786d6, &
4.269334710d5,-1.165954977d5, &
2.198700496d4,-2.827160468d3, &
2.372409350d2,-1.173264972d1, &
2.596865877d-1 ]
real(Float64), parameter :: n = 3.0
real(Float64) :: ee, fac, l, p
if(Erel.lt.90.0) then
ee = max(Erel * 1.d3 * n**2.0, 1.d3) !keV to eV
fac = 1.d0
else
ee = 90.0 * 1.d3 * n**2.0
fac = 2.d20 *(Erel*n**2.0)**(-7.0)
endif
l = log10(ee)
p = a(1) + a(2)*l + a(3)*l**2.0 + a(4)*l**3.0 + &
a(5)*l**4.0 + a(6)*l**5.0 + a(7)*l**6.0 + &
a(8)*l**7.0 + a(9)*l**8.0 + a(10)*l**9.0 + a(11)*l**10.0
sigma = fac*(10.d0**p)
end function p_cx_3_6inf_adas