The Optics Hutch (OPT) is situated in between 33-46 m from the source. It contains most of the main optical elements of the beamline, which are:
The first major component is a standard PETRA III high heat load monochromator. It is located at ~38 m and cooled by liquid nitrogen. Currently it is equipped with an independent Si(111) crystal pair (4.0-30.0keV) and Si(111) channelcut (5.0-17.0keV). While the crystal pair offers the possibility to operate with a fixed exit offset, the channelcut design offers a much higher angular stability of the beam at the price of reduced energy ranges and energy dependent exit offsets.
Next is a pair of flat (R > 100km) horizontally reflecting mirrors. The mirrors are coated with a Rhodium and a Platinum stripe to match the cutoff energy for higher energies to the experimental conditions.\
The mirrors are followed by the bremsstrahlung shield (often termed beamstop) in the optics hutch. Basically, the beamstop is a water-cooled Densimet collimator with holes for the pink beam (4mm diameter) and the monochromatic beam (4x11mm2). Both beams need to be offset from the white beam position by a minimum of 20mm. A girder with several optical elements has been installed after the beamstop.
Site note 1: The lowest reachable energy (~3.8keV) of the beamline is given by the minimum gap of the undulator of 9.8mm.
Site note 2:There is still some space available at the beginning of the optics hutch, which is reserved for a high heat load flat mirror to enable pink beam operation of the beamline.