qspec.v_e_d1  (  e ,  m ,  v0 = 0 ,  relativistic = True  )[source]

The first derivative $\frac{\partial v}{\partial E} = \frac{1}{amv(E)}$ with $a = \begin{cases}(\gamma(v_0) + E / (mc^2))^3, & \mathrm{True}\\1, & \mathrm{False}\end{cases}$

Parameters:

earray_like

The energy $E$ added to the kinetic energy of a body with velocity v0 (eV).

marray_like

The mass $m$ of the body (u).

v0array_like

The initial velocity $v_0$ of the body (m/s).

relativisticbool

The calculation is performed either relativistically (True) or classically (False). The default is True.

Returns:

outndarray

The first derivative $\partial v / \partial E$ of the velocity $v(E)$ of a body with mass m and velocity v0 with respect to the added energy e (m/(s eV)).