Calculates cross section for a proton-Hydrogen charge exchange interaction
from the state to the state at energy Erel
Type | Intent | Optional | Attributes | Name | ||
---|---|---|---|---|---|---|
real(kind=Float64), | intent(in) | :: | Erel | Relative collision energy [keV/amu] |
Cross Section []
function p_cx_2_3_adas(Erel) result(sigma)
!+Calculates cross section for a proton-Hydrogen charge exchange interaction
!+from the \(n=2\) state to the \(m=3\) state at energy `Erel`
!+
!+###Equation
!+ $$H^+ + H(2) \rightarrow H(3) + H^+$$
!+###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 :: a2s = [-3.513030327d5, 9.281116596d5, &
-1.086843398d6, 7.437325055d5, &
-3.296609685d5, 9.897503768d4, &
-2.039707143d4, 2.850670244d3, &
-2.587092857d2, 1.377382945d1, &
-3.268306303d-1 ]
real(Float64), dimension(11), parameter :: a2p = [-1.901264631d5, 5.124716103d5, &
-6.101921504d5, 4.234717934d5, &
-1.899866398d5, 5.764464326d4, &
-1.199087959d4, 1.689900512d3, &
-1.545334374d2, 8.285001228d0, &
-1.978656474d-1 ]
real(Float64), parameter :: n = 2.d0
real(Float64) :: ee, l, sigma2s, sigma2p
ee = max(Erel * 1.d3 * n**2.d0, 1.d3)
l = log10(ee)
sigma2s = a2s(1) + a2s(2)*l + a2s(3)*l**2.0 + a2s(4)*l**3.0 + &
a2s(5)*l**4.0 + a2s(6)*l**5.0 + a2s(7)*l**6.0 + &
a2s(8)*l**7.0 + a2s(9)*l**8.0 + a2s(10)*l**9.0 + a2s(11)*l**10.0
sigma2s = 10.d0**(sigma2s)
sigma2p = a2p(1) + a2p(2)*l + a2p(3)*l**2.0 + a2p(4)*l**3.0 + &
a2p(5)*l**4.0 + a2p(6)*l**5.0 + a2p(7)*l**6.0 + &
a2p(8)*l**7.0 + a2p(9)*l**8.0 + a2p(10)*l**9.0 + a2p(11)*l**10.0
sigma2p = 10.d0**(sigma2p)
sigma = (0.25*sigma2s + 0.75*sigma2p)
end function p_cx_2_3_adas