FROAMA —  Beamlines   (29-Jun-18   09:00—12:10)
Chair: J.L. Giorgetta, SOLEIL, Gif-sur-Yvette, France
Paper Title Page
Mechanical Engineering Instrument Design and Development for LCLS-II  
  • L. Zhang
    SLAC, Menlo Park, California, USA
  The high-repetition-rate FELs will enable a broad range of high-resolution, coherent pump probe experiments over a large photon energy range. On top of the extreme high peak power of the FEL, the average power of this high-repetition-rate FEL reaches several hundred watts. This combination of extreme high peak power and high average power becomes very challenging for the X-ray optics to preserve the FEL beam quality. As an example for X-ray optics - water cooled and dynamically bendable KB mirror, minimizing thermal deformation, bending the mirror to perfect ellipse shape. Managing the beam power of soft X-ray FEL with high energy per pulse and high average power needs windowless gas attenuator with differential pumping system. FEL beam from two different sources (SXR and HXR) or to split femtosecond FEL pulses and recombine them with a precisely adjustable delay opens numerous scientific applications such X-ray pump X-ray probe. The complexity of a delay system for LCLS-II includes multiple bounce crystals requiring femtosecond time delay accuracy and with the possibility of photon energy scan. In this paper, we will highlight design and development of these systems at LCLS.  
slides icon Slides FROAMA01 [17.482 MB]  
FROAMA02 A High Heat Load Double Crystal Monochromator and Its Cryo Cooling System for Heps -1
  • H. Liang, L. Gao, Y.C. Jiang, W.F. Sheng, S. Tang, A.Y. Zhou
    IHEP, Beijing, People's Republic of China
  • G. Cao
    University of Chinese Academy of Sciences, Beijing, People's Republic of China
  A high heat load double crystal monochromator and its cryo cooling system were designed and their prototypes were fabricated for the future HEPS. The mechanical and cooling structure of the DCM are introduced. The FEA results show the DCM is capable of cooling 870 watts of heat load. The cryo cooling system is also introduced. Test results show the pressure stability of the cryo cooling system is less than 2 mbar RMS. Offline heat load test of the DCM were carried out by a ceramic heater attached to the center of the incident surface of the first crystal, and 834 watts heat load were applied by the heater without boiling the liquid nitrogen. Offline absolute vibration measurement of the second crystal assembly was carried out by a laser interferometer under different cryo pump speed, pressure and heat load conditions, to find out the stability performance accordingly. An absolute vibration of 41 nrad RMS was measured, with the pump running at 45Hz, which has a cooling capability of 400 watts.  
slides icon Slides FROAMA02 [7.365 MB]  
R&D of Mirror Bending Techniques in BSRF  
  • M. Li, L. Gao, H. Han, Q. Han, X. Liu, S. Tang
    IHEP, Beijing, People's Republic of China
  High precision bending technology is development at Beijing Synchrotron Radiation Facility. We adopted two independent bending moment and variable width mirror geometry design, and no gravity compensation system, and use four rollers structure in long mirror bender and a special flexible hinge structure in short mirror bender. We test the benders' performance by our Flag-type LTP and get sub-200nrad RMS elliptical bending surface shape accuracy in full range, with 72h stability: 66nrad RMS for long mirror and 6nrad RMS for short mirror.  
slides icon Slides FROAMA03 [13.717 MB]  
European XFEL SASE3 Photon Beam Commissioning and Lesson Learned  
  • D. La Civita, H. Sinn
    XFEL. EU, Schenefeld, Germany
  European XFEL, the Free-Electron-Laser facility in Hamburg (Germany), started user operation in September 2017. The novel facility produces at MHz repetition rate, coherent, 1mJ energy, femto-second pulses in a wide photon energy range. The facility comprises of a linear accelerator and three beamlines: SASE1 works in the hard X-ray regime and it is presently in user operation; SASE3 is the soft X-ray beamline and it is in advanced commissioning with beam and ready to receive users at the end of 2018; SASE2 is the second hard X-ray beamline that saw FEL light in early May 2018 and it is now in beam commissioning phase. The length of the beamlines together with the high energy and high repetition rate pulses place interesting and new engineering design challenges. The experience gained during the commissioning allows confirmations, revisions and upgrade of the present design of devices. This contribution reports about the commissioning of the SASE3 beamline and reviews part of the beamline device performance. Focus is given on the grating monochromator commissioning with beam and also on the mechanical performance verified during the device technical commissioning.  
slides icon Slides FROAMA04 [16.106 MB]  
FROAMA05 Engineering Design and Commissioning Performance of the ESM and Six Soft X-Ray Beamlines at NSLS-II -1
  • Y. Zhu, S.L. Hulbert, M. Idir, I. Jarrige, S. O'Hara, E. Vescovo
    BNL, Upton, Long Island, New York, USA
  Two of the five NSLS-II Experimental Tools (NEXT) project insertion-device beamlines developed for the NSLS-II facility at Brookhaven National Laboratory are state-of-the-art soft X-ray beamlines covering the 15 eV- 1500 eV photon energy range. The engineering challenges of these two beamlines included: accurate and realistic optical simulations, nearly perfect optic figure and mechanical/thermal implementation, and advanced diagnostics systems developed in-house. The measured performance (flux, spot size, resolution) of these two beamlines closely matches the calculated values. Here, the engineering design and performance measurements of these two beamlines are presented.  
slides icon Slides FROAMA05 [15.529 MB]  
High Resolution Monochromator for IXS Experiments at Petra III Beamline P01  
  • F.U. Dill
    DESY, Hamburg, Germany
  Since April 2017, beamline P01 at Petra III DESY is providing monochromatic X-Rays at energies down to 2.5keV. An in-house developed High Resolution Monochromator (HRM) for High Vacuum (5x10-7mbar) was assembled and installed in early summer 2017. As a core component a high precision goniometer was designed. A piezo actuator provides the required angular range of 40°. The angular resolution is specified with 0.5microrad and is controlled by an encoder. Three goniometers can be moved independently along the three linear directions. The linear movements are assembled by low cost linear guide components and driven by toothed wheels and toothed bars or by spindles directly attached to the motor shaft. First beamtimes in 2017 with channel cut Si (111) crystals showed promising results - HRM providing x-rays with a bandwidth of 100meV (at 2.840keV). The resolution of the goniometers is better than 0,1microrad with a stability of ±50nanorad. In spring 2018 a four-bounce setup with additional standard piezo manipulators was designed to reach a bandwidth between of 50meV. After installation and first measurements in May 2018 a total energy resolution of 100meV was achieved.  
slides icon Slides FROAMA06 [4.928 MB]  
FROAMA07 ESRF Double Crystal Monochromator Prototype Project -1
  • R. Baker, D. Baboulin, R. Barrett, P. Bernard, G. Berruyer, J. Bonnefoy, M. Brendike, P.M. Brumund, Y. Dabin, L. Ducotte, H. Gonzalez, G. Malandrino, P. Marion, O. Mathon, T. Roth, R. Tucoulou
    ESRF, Grenoble, France
  Spectroscopy beamlines at the ESRF are equipped with a generic model of double crystal monochromator, originally acquired in the 1990's. After over 15 years of continuous service, their conception, although pioneering 20 years ago, can no longer meet the challenge of present and future scientific goals in terms of position and angular stability, thermal stability, cooling system, vibration, control and feedback, particularly in view of the ESRF - EBS upgrade. Considering the above issues, a feasibility phase was launched to develop a prototype DCM dedicated to future spectroscopy applications at the ESRF. Specifications : derived from expected performance of the EBS upgrade and scientific objectives - are extremely challenging, especially in terms of mechanical and thermal stability and impose the adoption of several innovative design strategies. The prototype is currently in the assembly phase and tests of the complete system are planned before the end of 2018. An overview of the DCM prototype project will be given, including specifications, major design options implemented and various validated concepts. Current project status and first test results will also be presented.  
slides icon Slides FROAMA07 [24.523 MB]  
Refinements of SPring-8 Standard Monochromators with Cryogenically Cooled Silicon Crystals toward 50 nrad-Stability  
  • H. Yamazaki, Y. Ikeya, H. Kishimoto, Y. Matsuzaki, T. Miura, H. Ohashi, Y. Senba, Y. Shimizu, T. Takeuchi, M. Tanaka, I. Tsuboki
    JASRI/SPring-8, Hyogo, Japan
  In SPring-8, 21 of the 28 X-ray undulator beamlines have the same sets of a double-crystal monochromator (DCM) and a cryogenically cooling system. A remaining problem is vibration for the forthcoming upgraded SPring-8. For certain experiments, vibration seems to fluctuate the source position. The virtual fluctuation, which increases the effective source size, degrades high-density nanobeam made by direct projection of the source. When a DCM is placed at 40 m downstream from a source with 6-um size, the vibration should be 50 nrad to suppress 20%-increase of the source size. The vibration was over 800 nrad in 2011. We have continued improving low-vibration flexible tubes for transport tube of liquid nitrogen, high-rigidity tilt stages, and temperature controllers of the coolant. The latest-version refinements were carried out to 5 DCMs in 2017FY. The vibrations were reduced to about 110 nrad in 4 DCMs and 55 nrad for one.  
slides icon Slides FROAMA08 [4.348 MB]