CollisionDB: DataSet D936

$e^{-} + Be 2 s 3 s^{1} S \to {Be}^{+} + 2 e^{-}$

Process	EIN: Ionization
Data type	cross section \| uploaded on 2022-05-26
Comment	Analytic fits for electron-impact ionization cross sections for BeI
Recommended	Yes

Method	Theory
Columns	E /eV sigma /cm²
Uncertainty	15 %
Ref	B7: Dipti, T. Das, K. Bartschat, I. Bray, D. Fursa, O. Zatsarinny, C. Ballance, H. Chung, Y. Ralchenko, "Recommended electron-impact excitation and ionization cross sections for Be I ", Atomic Data and Nuclear Data Tables 127-128, 1-21 (2019). [10.1016/j.adt.2018.11.001]
Data	Download (data from fit)

Fitted Data

Fit Function
Details

σ (x) = (\frac{10^{- 13}}{x I}) (A_{1} \ln (\frac{x}{I}) + \sum_{i = 2}^{6} A_{i} {(1 - \frac{I}{x})}^{i - 1})

Python

def Ion_fit_Be(x  A1, A2, A3, A4, A5, A6, I):
    """
    This function calculates electron impact ionization cross sections (in cm2) of 
    Be I.
    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* 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

Fit Coefficients

A1	3.733e-01
A2	2.210e-01
A3	-4.860e+00
A4	2.017e+01
A5	-2.991e+01
A6	1.506e+01
I	2.544e+00

x-range

–

DataSet D936

e−+Be2s3s1S→Be++2e−

Fitted Data

$e^{-} + Be 2 s 3 s^{1} S \to {Be}^{+} + 2 e^{-}$