CollisionDB: DataSet D108115

\[\mathrm{H}^{+} + \mathrm{H} \; 1s \rightarrow \mathrm{H} + \mathrm{H}^{+}\]

Process	HCX: Charge Transfer
Data type	cross section \| uploaded on 2023-02-08
Comment	Fit function taken from p78.Error: E<0.01keV/u -> 10%, 0.01keV/u<E<1keV/u -> 15%, 1keV/u<E<100keV/u -> 10%, 100keV/u<E<2000keV/u -> 20%, E<2000keV/u -> 40%

Method	semi-empirical
Frame	Target
Columns	E /eV u^-1 sigma /cm²
Ref	B37: R. K. Janev, J. J. Smith, "Cross sections for collision processes of hydrogen atoms with electrons, protons, and multiply charged ions", IAEA- Atomic and Plasma–Material Interaction Data for Fusion, Vienna 4 (1993). [https://www.iaea.org/publications/1839/atomic-and-plasma-material-interaction-data-for-fusion]
Data	Download (data from fit)

Fitted Data

Fit Function
Details

\[\sigma_{CX}^{n=1}(E)= \frac{10^{-16}A_1 \ln \big( \frac{A_2}{E} + A_6 \big)}{1 + A_3E + A_4E^{3.5} + A_5E^{5.4}}\]

Python

def h_hcx_janev(E, A1, A2, A3, A4, A5, A6):
    """
    This function calculates proton impact charge exchange cross sections (in cm2) of 
    H n=1.
    param E: requested electron-impact energy in keV
    type E: float, np.ndarray
    param Ai: fit coefficient 
    type Ai: float
    """
    sigma = 1e-16 * A1 * np.log(A2/E + A6) / (1 + A3*E + A4*E**3.5 + A5*E**5.4)
    return sigma

Fit Precision

2.3 %

Fit Coefficients

A1	3.235e+00
A2	2.359e+02
A3	3.837e-02
A4	3.807e-06
A5	1.183e-10
A6	2.371e+00

x-range

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