LCODE-specific methods

The methods in this page are accessible to a data object if:

<data_obj>.attrs['data_origin'] == 'lcode'#(1)!

1. <data_obj> may be either ozzy.DataArray or ozzy.Dataset

convert_q

convert_q(dxi, n0, q_var='q')

Convert the charge variable to physical units (in units of \(e\)).

Parameters:

Name	Type	Description	Default
dxi	float	The grid spacing in the longitudinal direction in normalized units, i.e., in units of \(k_p^{-1}\). or \(\mathrm{cm}\).	required
n0	float	The reference density, in \(\mathrm{cm}^{-3}\).	required
q_var	str	Name of the charge density variable.	'q'

Returns:

Type	Description
None	The dataset is modified in place.

Notes

The charge in physical units (\(\mathrm{C}\)) is obtained by multiplying the normalized charge with the factor \(\frac{\Delta \hat{\xi}}{2} \frac{I_A}{\omega_p}\), where \(\Delta \hat{\xi} = k_p \Delta \xi\) is the normalized longitudinal cell size and \(I_A\) is the Alfvén current, defined as:

\[ I_A = 4 \pi \varepsilon_0 \frac{m_e c^3}{e} \approx 17.045 \ \mathrm{kA} \]

Note that the charge is given in units of the elementary charge \(e\) after this method is applied.

Examples:

Particle data

import ozzy as oz
file = 'path/to/particle/file/tb02500.swp'
ds = oz.open('lcode', file)
ds.ozzy.convert_q(dxi=0.01, n0=2e14, q_var='q')
print(ds)