def header_translate_inverse(header_name):
    """Translate parameter names back from headers."""
    name_dict = {'XCENREF': 'xcen_ref',
                 'YCENREF': 'ycen_ref',
                 'ZENDIR': 'zenith_direction',
                 'ZENDIST': 'zenith_distance',
                 'FLUX': 'flux',
                 'BETA': 'beta',
                 'BCKGRND': 'background',
                 'ALPHAREF': 'alpha_ref',
                 'TEMP': 'temperature',
                 'PRESSURE': 'pressure',
                 'VAPPRESS': 'vapour_pressure'}
    return name_dict[header_name]