def _nonpar_core(event_list, dead_time_end, mask):
    """Numba-compiled core of the non-paralyzable dead time calculation.

    Parameters
    ----------
    event_list : array of floats
        Event times of arrival
    dead_time_end : array of floats
        End of the dead time of each event
    mask : array of bools
        Final mask of good events. Initially, all entries must be ``True``

    Return
    ------
    mask : array of bools
        Final mask of good events
    """
    for i in range(1, len(event_list)):
        if (event_list[i] < dead_time_end[i - 1]):
            dead_time_end[i] = dead_time_end[i - 1]
            mask[i] = False
    return mask