_diffrn_source.diffrn_id       's1'
    _diffrn_source.source          'rotating anode'
    _diffrn_source.type            'Rigaku RU-200'
    _diffrn_source.power           50
    _diffrn_source.current        180
    _diffrn_source.size            '8mm x 0.4 mm broad-focus'