imap_processing.idex.idex_l2a.calculate_velocity_and_mass#

imap_processing.idex.idex_l2a.calculate_velocity_and_mass(sig_amp: float, t_rise: float, t_rise_params: ndarray, yield_params: ndarray) → tuple[float, float]#

Calculate velocity and mass estimates.

The fitted target signals are used to generate IDEX’s specific charge yield as a function of the impact speed. The calibration curve is fitted with a segmented power law distribution. The charge yield curve enables the mass of the dust particle to be estimated from the total charge it generates on the target.

Parameters:

  • sig_amp (float) – Signal amplitude.

  • t_rise (float) – T_rise fit parameter from the target fit.

  • t_rise_params (np.ndarray) – Calibration parameters for rise time.

  • yield_params (np.ndarray) – Calibration parameters for yield.

Returns:

  • v_est (float) – Estimated velocity.

  • mass_est (float) – Estimated mass.