CollisionDB: DataSet D807

$e^{-} + Be 2 s 2 p^{3} P \to Be 2 p^{2}^{3} P + e^{-}$

Process	EEX: Excitation
Data type	cross section \| uploaded on 2022-05-26
Comment	Analytic fits for electron-impact excitation collision strengths for BeI as a function of energy in terms of threshold
Recommended	Yes

Method	Theory
Columns	E /eV sigma /cm²
Threshold	4.67616 eV
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

Ω (x) = (\frac{x - 1}{x + A_{1}}) (A_{2} \ln (x) + A_{3} + \frac{A_{4}}{x} + \frac{A_{5}}{x^{2}} + \frac{A_{6}}{x^{3}})

Python

def DA_fit_Be(x, A1, A2, A3, A4, A5, A6):
    """
    This function calculates the dimensionless collision strengths for electron 
    impact excitation of BeI.
    param x: requested electron-impact energy in threshold units
    type x: float, np.ndarray
    param Ai: fit coefficients
    type Ai: float
    """
    Omega = ((x-1)/(x+A1))*(A2 * np.log(x) + A3 + A4/x + A5/x**2 + A6/x**3)
    return Omega

Data Type

collision strength

Fit Coefficients

A1	6.003e+00
A2	3.697e+01
A3	1.074e+02
A4	1.107e+02
A5	3.442e+02
A6	-5.622e+02

x-range

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DataSet D807

e−+Be2s2p3P→Be2p23P+e−

Fitted Data

$e^{-} + Be 2 s 2 p^{3} P \to Be 2 p^{2}^{3} P + e^{-}$