TY - CONF AU - Matsuba, S. AU - Harada, K. AU - Katoh, M. AU - Kawase, K. AU - Shimada, K.S. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Design Study of an Electron Storage Ring for the Future Plan of Hiroshima Synchrotron Radiation Center. J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Hiroshima synchrotron radiation center equips a 700 MeV electron storage ring nicknamed HiSOR. It has been operated for more than 20 years. The emittance of HiSOR is 400 nm, which is larger by one or more orders of magnitude than typical modern synchrotron light sources. Therefore, as the future plan of the facility, a new low emittance storage ring is desired. Several designs have been examined. In the newest version, we have selected the lattice structure similar to ASTRID 2 compact light source in Aarhus University, Denmark. The design goal is the energy of around 500 MeV, the circumference shorter than 50 m and the emittance smaller than 10 nm with straight sections for undulators more than 4. In this conference, we report the latest result from the design study. PB - JACoW Publishing CP - Geneva, Switzerland SP - 200 EP - 202 KW - storage-ring KW - synchrotron KW - radiation KW - emittance KW - synchrotron-radiation DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPGW048 UR - http://jacow.org/ipac2019/papers/mopgw048.pdf ER - TY - CONF AU - Kondo, K. AU - Bellan, L. AU - Cara, P. AU - Dzitko, H. AU - Grespan, F. AU - Heidinger, R. AU - Kwon, S. AU - Podadera, I. AU - Sakamoto, K. AU - Scantamburlo, F. AU - Shinya, T. AU - Sugimoto, M. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Radiation Measurement in the 1st Beam Commissioning Campaign of the LIPAc RFQ J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The 1st proton beam acceleration of the Linear IFMIF Prototype Accelerator (LIPAc) through its novel RFQ was succeeded on 13th June 2018. Addition to plenty of beam diagnostics equipped in the beam line, we prepared some radiation detectors placed around the accelerator in order to acquire supplemental information of the beam, as an indirect measurement. In the first day of the beam injec-tion to the RFQ, the gamma-rays corresponding to certain excited states of Al of the low power beam dump were successfully detected by a LaBr3(Ce) scintillation detec-tor. Some neutrons, which would originate from the inter-action of protons with Cu somewhere, were also ob-served. These results proved that the beam was certainly accelerated up to about 2.5 MeV, and provided us a defin-itive confidence that the RFQ was working appropriately from the very beginning of the commissioning. Also, the comparison of the radiation yields with the RFQ trans-mission provided additional information on the beam energy distribution. PB - JACoW Publishing CP - Geneva, Switzerland SP - 964 EP - 967 KW - rfq KW - neutron KW - proton KW - radiation KW - MMI DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPTS047 UR - http://jacow.org/ipac2019/papers/mopts047.pdf ER - TY - CONF AU - Shimosaki, Y. AU - Bellan, L. AU - Brañas Lasala, B. AU - Cara, P. AU - Chauvin, N. AU - Comunian, M. AU - Duglue, G. AU - Dzitko, H. AU - Fagotti, E. AU - Heidinger, R. AU - Kasugai, A. AU - Kobayashi, H. AU - Kondo, K. AU - Oliver, C. AU - Pisent, A. AU - Podadera, I. AU - Sakamoto, K. AU - Sugimoto, M. AU - Takayama, K. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Lattice Design for 5MeV-125mA CW RFQ Operation in the LIPAc J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The installation and commissioning of the LIPAc are ongoing under the Broader Approach agreement, which is the prototype accelerator of the IFMIF for proof of princi-ple and design. The deuteron beam will be accelerated by the RFQ linac from 100 keV to 5 MeV during the com-missioning phase-B and by the SRF linac up to 9 MeV during the phase-C. The commissioning phase-B+ will be implemented between phase-B and C to complete the engineering validation of the RFQ linac before installing the SRF linac. The lattice for the deuteron beam of 5 MeV and 125 mA at the commissioning phase-B+ was designed. PB - JACoW Publishing CP - Geneva, Switzerland SP - 977 EP - 979 KW - linac KW - SRF KW - rfq KW - MMI KW - MEBT DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPTS051 UR - http://jacow.org/ipac2019/papers/mopts051.pdf ER - TY - CONF AU - Kondo, C. AU - Fukami, K. AU - Fukui, T. AU - Nakazawa, S. AU - Nishimori, N. AU - Saji, C. AU - Takano, S. AU - Tanaka, H. AU - Watanabe, T. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Digital Control System of High Precision Magnet Power Supply for SPring-8-II J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - For the SPring-8 upgrade plan, SPring-8-II, a variety of magnet power supplies (PS) from 10 W to larger than 100 kW with a high current stability of about 10 ppm (pk-pk, typ.) are required. In order to develop the PSs within a given time and budget, we plan to use a common control system based on a digital control technology that can be adopted for the variety and the high precision PSs. The system consists of a high-precision analog-digital converter (ADC) circuit and a field programmable gate array (FPGA). Since the precision of the ADC circuit determines the current stability of the PS, we first developed the ADC circuit of high accuracy of less than 10 ppm (pk-pk). A proportional-integral (PI) control logic and a digital pulse width modulation (PWM) function was implemented in the FPGA firmware. These functions can be easily modified for each power supply by a desktop computer. We prototyped a DC power supply equipped with the newly developed digital feedback control system and confirmed that the current fluctuation was suppressed to less than 10 ppm (pk-pk). In the presentation, we will report the current status and future perspective of our power supply development including the evaluation results of the new circuits and the power supply we have developed. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1259 EP - 1262 KW - controls KW - feedback KW - power-supply KW - FPGA KW - synchrotron-radiation DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPMP014 UR - http://jacow.org/ipac2019/papers/tupmp014.pdf ER - TY - CONF AU - Obina, T. AU - Arakawa, D.A. AU - Egi, M. AU - Furuya, T. AU - Haga, K. AU - Hajima, R. AU - Harada, K. AU - Honda, T. AU - Honda, Y. AU - Honma, T. AU - Kako, E. AU - Kato, R. AU - Kawata, H. AU - Kobayashi, Y. AU - Kojima, Y. AU - Konomi, T. AU - Matsumura, H. AU - Miura, T. AU - Miyajima, T. AU - Nagahashi, S. AU - Nagai, R. AU - Nakai, H. AU - Nakamura, N. AU - Nakanishi, K. AU - Nigorikawa, K.N. AU - Nishimori, N. AU - Nogami, T. AU - Qiu, F. AU - Sagehashi, H. AU - Sakai, H. AU - Sakanaka, S. AU - Sawamura, M. AU - Shimada, M. AU - Tadano, M. AU - Takahashi, T. AU - Takai, R. AU - Tanaka, O.A. AU - Tanimoto, Y. AU - Uchiyama, T. AU - Umemori, K. AU - Yamamoto, M. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - 1 mA Stable Energy Recovery Beam Operation with Small Beam Emittance J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - A compact energy-recovery linac (cERL) have been operating since 2013 at KEK to develop critical components for ERL facility. Details of design, construction and the result of initial commissioning are already reported*. This paper will describe the details of further improvements and researches to achieve higher averaged beam current of 1 mA with continuous-wave (CW) beam pattern. At first, to keep the small beam emittance produced by 500 kV DC-photocathode gun, tuning of low-energy beam transport is essential. Also, we found some components degrades the beam quality, i.e., a non-metallic mirror which disturbed the beam orbit. Other important aspects are the measurement and mitigation of the beam losses. Combination of beam collimator and tuning of the beam optics can improve the beam halo enough to operate with 1 mA stably. The cERL has been operated with beam energy at 20 MeV or 17.5 MeV and with beam rep-rate of 1300 MHz or 162.5 MHz depending on the purpose of experiments. In each operation, the efficiency of the energy recovery was confirmed to be better than 99.9 %. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1482 EP - 1485 KW - operation KW - emittance KW - cavity KW - linac KW - gun DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPGW036 UR - http://jacow.org/ipac2019/papers/tupgw036.pdf ER - TY - CONF AU - Matsuba, S. AU - Fujimoto, M. AU - Hosaka, M. AU - Katoh, M. AU - Kawase, K. AU - Konomi, T. AU - Miyamoto, A. AU - Sasaki, S. AU - Yamamoto, N. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Experimental Demonstration of Vector Beam Generation With Tandem Helical Undulators J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Vector beam is a light beam with spatially modulated polarization state across the beam. Particular examples of vector beam are radial and azimuthal polarization which have donut-shaped intensity and radially and azimuthally oriented linear polarization state. Vector beam has long been interest in the laser community and it is well known that vector beam can be created by superposing two optical vortex beams which have spiral wave fronts. It has been demonstrated that optical vortex beam can be generated from a helical undulator as harmonics. Therefore, we propose a scheme to generate vector beam by superposing two optical vortex beams from two helical undulators in tandem, based on the principle of the ’crossed undulator’. The experiment was carried out at UVSOR BL1U. In this paper, we describe the principle and the experimental details. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1766 EP - 1768 KW - polarization KW - undulator KW - experiment KW - radiation KW - simulation DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB037 UR - http://jacow.org/ipac2019/papers/tuprb037.pdf ER - TY - CONF AU - Sumitomo, Y. AU - Hajima, R. AU - Hayakawa, Y. AU - Sakai, T. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Simulation of Short-Pulse Generation from a Dynamically Detuned IR-FEL Oscillator and Pulse Stacking at an External Cavity J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - At the LEBRA facility of Nihon U., we have an IR-FEL oscillator to generate radiations in the range of wavelengths 1-6 um for various experiments. A research program has been established to explore the application of the IR-FEL to generate attosecond UV and X-ray pulses through the high harmonic generation (HHG) in noble gases, where the IR-FEL pulses must have a high-peak power and a short-pulse duration. The property of generated FEL pulse is affected by the cavity length detuning of FEL oscillator as well as the small signal gain and the cavity loss. The operation at a small- or zero-detuning length is necessary to generate a FEL pulse shorter than the bunch length, although it requires a long macro-pulse to reach the saturation. For the short FEL pulse generation within a limited macro-pulse length at the LEBRA LINAC, we apply a dynamical modulation to the electron bunch repetition, that is equivalent to a dynamical detuning of the FEL cavity length. We illustrate the potential performance of the IR-FEL with the dynamical detuning by time-dependent 3D FEL simulations. We also evaluate the enhancement of the FEL pulses by an external cavity stacking for the sake of the HHG application. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1778 EP - 1781 KW - FEL KW - cavity KW - electron KW - simulation KW - radiation DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB041 UR - http://jacow.org/ipac2019/papers/tuprb041.pdf ER -