def calc_RASE_Sensitivity(counts, livetime, source_act_fact):
    """
    Derived from the documentation formula for calcuating RASE Sensitivity.
    For dose, source_act_fact is microsieverts/hour
    For flux, source_act_fact is counts*cm^-2*s-1 in the photopeak of interest
    :param counts:
    :param livetime:
    :param uSievertsph:
    :return:
    """
    return (counts.sum() / livetime) / source_act_fact