DataSet D108024

\[\mathrm{He}^{2+} + \mathrm{H} \; n=2 \rightarrow \mathrm{He}^{2+} + \mathrm{H} \; n=3\]


Process HEX: Excitation
Data type cross section | uploaded on 2023-02-08
Comment Fit function taken from p92. Error: E<0.5keV/u -> 100%, 0.5keV/u<E<20keV/u -> 50%, 20keV/u<E<100keV/u -> 30%, E<100keV/u -> 20%

Methodsemi-empirical
FrameTarget
Columns
  1. E /eV u-1
  2. sigma /cm2
Ref
DataDownload (data from fit)

Fitted Data

Fit Function
Details
\[\sigma_{ex}^{2\rightarrow 3,4,5}(E) =10^{-16}A_1 \Bigg[\frac{e^{-\frac{A_2}{E}}\ln(1+A_3E)}{E} + \frac{A_4e^{-A_5E}}{E^{A_6}}\Bigg]\]
Python
def h_hex_janev_25(E, A1, A2, A3, A4, A5, A6):
    """
    This function calculates proton impact excitation cross sections (in cm2) of 
    H n=2 to n=3,4,5 and n=3 to n=4,5,6 and He+2 of H n=2 to n=3,4,5 and n=3 to n=4,5,6.
    param E: requested impact energy in keV/u
    type E: float, np.ndarray
    param Ai: fit coefficient 
    type Ai: float
    """
    sigma = 1e-16 * A1 * (np.exp(-A2/E) * np.log(1 + A3*E) / E + A4*np.exp(-A5*E)/E**A6)
    return sigma
Fit Precision2.1 %
Fit Coefficients
A1
 1.864e+03
A2
 1.939e+01
A3
 1.390e-01
A4
 2.450e-03
A5
 2.966e-01
A6
-1.756e+00
x-range –