physics.py 文件源码

def compute_ess_transmission(beam_sigma, slits, dispersion):
    """Compute the transmission as a function of the momentum offset (in %) from a simple analytical model."""
    n_steps = 10000
    dx = 3.0/n_steps
    sigma = beam_sigma/2.8
    slits_at = slits/dispersion
    error = np.arange(-1.5, 1.5, dx)
    slits = np.zeros(n_steps)
    slits[np.where((error < slits_at) & (error > -slits_at))] = 1.0
    beam = np.exp(-(error/sigma)**2/2)
    return np.roll(np.convolve(slits, beam, mode="same"), -1)/np.trapz(beam)