DataSet D123991

\[\mathrm{e}^- + \mathrm{Be}^{+} \; 3p \; {}^{2}\mathrm{P} \rightarrow \mathrm{Be}^{2+} + 2\mathrm{e}^-\]

Process EIN: Ionization
Data type cross section | uploaded on 2024-01-18
Comment Analytic fits for electron-impact ionization cross sections for Be+. The cross sections calculations take into account of ioinzation of valence electron as well as core 1s electrons. The uncertainty in the original cross sections is 10 %, while the fitted ones have a total uncertainty of 15 %.
RecommendedYes
MethodCCC: Convergent close-coupling
Columns
  1. E /eV
  2. sigma /cm2
Ref
  • B227: Dipti, I. Bray, D. Fursa, H. Umer, C. Hill, Y. Ralchenko, "Recommended electron-impact excitation and ionization cross sections for Be II", Atomic Data and Nuclear Data Tables, 101634 (2024). [10.1016/j.adt.2023.101634]
DataDownload

Fitted Data

Fit Function
Details		 \[\sigma (x) = \left( \frac{10^{-13}}{xI} \right) \left(A_1^2 \ln\left( \frac{x}{I} \right) + \displaystyle\sum_{i=2}^{6}A_i\left(1-\frac{I}{x}\right)^{i-1} \right)\]
Python 
def Ion_fit_Be1(x  A1, A2, A3, A4, A5, A6, I):
    """
    This function calculates electron impact ionization cross sections (in cm2) of 
    Be II.
    param x: requested electron-impact energy in eV
    type x: float, np.ndarray
    param Ai: fit coefficient 
    type Ai: float
    param I: ionization energy in eV
    type I: float
    """
    sigma = ((1e-13/x/I)*(A1**2 * np.log(x/I) + A2 * (1-(I/x)) + A3 * (1-(I/x))**2 
                         + A4 * (1-(I/x))**3 + A5 * (1-(I/x))**4 + A6 * (1-(I/x))**5)  
    return sigma
Data Typecross section
Fit Coefficients 
A1
 7.615e-03
A2
 6.213e-01
A3
-3.304e+00
A4
 1.296e+01
A5
-1.848e+01
A6
 9.098e+00
x-range –