Design and fabrication of liquid nitrogen cooled double crystal monochromator for PLS-II Seungyu Rah (Pohang Accelerator Laboratory, POSTECH, Korea) Nov. 12. 2014 ICABU2014 __________________________________________ICABU 2014 Seungyu Rah

__________________________________________ICABU 2014 Seungyu Rah Contents Introduction PAL’s effort for developing/ standardizing common beamline instruments PAL’s effort for developing mirror manipulator system Development of Double crystal monochromator Discussion Summary __________________________________________ICABU 2014 Seungyu Rah

Introduction - Beamlines at Pohang Light Source May 2013 30 working 23 x-ray 11 soft x-ray 19 I/D BLs __________________________________________ICABU 2014 Seungyu Rah

Introduction - Beamlines Beamline in synchrotron Light Source Is a unit of experimental system Is consisted of Safety system at front-end Photon beam manipulation system Experimental system Safety system Vacuum safety High energy radiation safety Thermal heat Common parts Photon beam manipulation system Spatial filtering(Slits) Deflection and focusing(Mirrors) Monochromatization(Monochromator, Grating/Crystal) Common parts High precision & stability Experimental system Sample Detector Environmental control(temperature/Pressure) Mechanical motion(Sample/detector) High precision and stability Unique design for the purpose __________________________________________ICABU 2014 Seungyu Rah

__________________________________________ICABU 2014 Seungyu Rah Introduction - construction of beamline and keeping own design of instruments Construction of beamline Costs ~ $5M Needs ~3 years Needs 6~10 man-year Man power dedicate to construction and operation Developing/ Keeping/ transferring own design of Instruments Shares Modular Design Same parts Saves cost for Manufacturing Maintenance Keeping spare part Reduces time for Delivery Maintenance Helps Better understanding of instruments Improvement of instruments Development of similar instruments May limit the choice Hidden cost Own test system Maintaining the technique Dedicated manpower Proto-type Trial and fails __________________________________________ICABU 2014 Seungyu Rah

PAL’s effort for developing/ standardizing common beamline instruments Software EPICS, LabView, Mathlab, SPEC based programs Electronic/electric instruments Baking controller Motor controller/driver Interlock system Photon beam position monitor Insertion devices Undulator In-vacuum undulator wiggler Mechanical system Support structure Slit, photon shutter, safety shutter optical table, experimental table fast closing shutter Optical instruments Mirror manipulator Monochromator(Crystal) __________________________________________ICABU 2014 Seungyu Rah

PAL’s effort for developing mirror manipulator system __________________________________________ICABU 2014 Seungyu Rah

PAL’s effort for developing mirror manipulator system __________________________________________ICABU 2014 Seungyu Rah

PAL’s effort for developing mirror manipulator system 1st trial in 1994 consistent trial and improvement in design, since 2000 By 2011, there were 66 mirror system have been built PAL owns the design and improves Adjustment of mirror position : 5 deg. Of freedom Adjustment of bending radius Need high precision and stability One of the most successful system The contractor has been chosen by biding, at the beginning stage Later, the contractor has been fixed for the performance of the system By the hand on experience, the contractor started commercial production More than 15 sets has been sold to outside PLS __________________________________________ICABU 2014 Seungyu Rah

Development of Double crystal monochromator __________________________________________ICABU 2014 Seungyu Rah

Development of Double crystal monochromator Experience(not fully tested) 1st trial for DCM in 1994 2nd trial for DCM in 2000 Two more for DMM Motive PLS-II upgrade(‘09-’11) Change of beam parameter 6 BLs moved from BD to ID Short of budget Limited choice Requirement Construction of 10 set Within 3 years Liquid nitrogen cooled DCM Fixed beam offset Reliable performance Strategy(Systematic approach) Requirement is clear Known working principle High precision(Order 1 higher than necessary resolution) Stability(mechanical/thermal) As simple design as possible Depend on liable parts Monitoring system(motion/temperature) Make proto-type Prove the performance by test Limited man-power Schematic design and test 4-physicists 1-electrical/software engineer Local contractor Detail design Fabrication __________________________________________ICABU 2014 Seungyu Rah

Development of Double crystal monochromator Workscope of PAL Choice of contractor Fix the specification Schematic design Choice of parts Order the parts Order Proto-type operation software Lab test Beamline test Evaluation and modification Order for duplication BL operation of proto-type Workscope of contractor Detail design(CAD) Fabrication Precision Assembly(CMM) Integration of electronics system Primary motion test Help the lab test Installation Modification of detail design Duplication __________________________________________ICABU 2014 Seungyu Rah

Development of Double crystal monochromator 11 sets of DCMs have been fabricated 3 kind of DCMs have been fabricated Single type DCM : 8 sets Dual type DCM : 1 set Asymmetrical cut DCM : 2 sets 8 sets of DCMs are in operation 6 single type DCMs, since Feb. 2012 2 asymmetrical cut DCM: since Aug. 2012 1 set of single type DCM is in commissioning, since Feb. 2014 Fabrication cost 270K US$/set( 1/3~1/2 of commercial system by price of 2011) Parts Fabrication Assembly Installation Manpower 3 man-year of physists 0.5 man-year of engineer 1 set of CCM is under fabrication The technical transfer is going on to the contractor for the design, test and evaluation technique __________________________________________ICABU 2014 Seungyu Rah

Discussion developing and improving an instrument for BL Development requires Big motivation Experience Time Effort Money Benefits Save fabrication cost Save maintenance cost Easy maintenance for the clones Easy development of similar system To keep or improve the technique, you need Continuous attention for Demand New technique/parts idea Dedicated manpower To keep test facility Technical transfer to contractor Can Create new business opportunity Can take over your effort to keep or improve the technique Additional collaboration must be beneficial for both parties __________________________________________ICABU 2014 Seungyu Rah

__________________________________________ICABU 2014 Seungyu Rah Summary PAL’s effort to develop/standardize beamline components is introduced The development of DCM is introduced The necessity of technical transfer of the development to industry is discussed __________________________________________ICABU 2014 Seungyu Rah

__________________________________________ICABU 2014 Seungyu Rah Thank you for your attention !! __________________________________________ICABU 2014 Seungyu Rah