TY - CONF AU - Sue, Y. AU - Futatsukawa, K. AU - Hasegawa, K. AU - Iijima, T. AU - Iinuma, H. AU - Inami, K. AU - Ishida, K. AU - Kawamura, N. AU - Kitamura, R. AU - Kondo, Y. AU - Mibe, T. AU - Miyake, Y. AU - Morishita, T. AU - Nakazawa, Y. AU - Otani, M. AU - Saito, N. AU - Takeuchi, Y. AU - Ushizawa, T. AU - Yamazaki, T. AU - Yasuda, H.Y. AU - Yotsuzuka, M. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - A Bunch Structure Measurement of Muons Accelerated by RFQ Using a Longitudinal Beam-Profile Monitor With High Time Resolution J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - J-PARC E34 experiment intends to measure the anomalous magnetic moment and electric dipole moment of muon precisely by a different way from the previous experiment. In this experiment, a low-emittance muon beam is provided using the muons with the thermal energy and the four-stage linac. The demonstration of the first muon RF acceleration with an RFQ linac was conducted and the transverse profile of the accelerated muons was measured last year. As one of the remaining issues for the beam-diagnostic system, the longitudinal beam profile after the RFQ should be measured to match the profile to the designed acceptance of the subsequent accelerator. For this purpose, the new longitudinal beam monitor using the micro-channel plate is under development. The time resolution aims to be around 30 to 40 ps corresponding to 1 % of a period of an operation frequency of the accelerator, which is 324 MHz. On November 2018, the bunch structure of accelerated muons of 89 keV with the RFQ was measured using this monitor at the J-PARC MLF. The latest analysis result of this measurement will be reported in this poster. PB - JACoW Publishing CP - Geneva, Switzerland SP - 37 EP - 40 KW - rfq KW - experiment KW - linac KW - background KW - electron DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOZZPLM2 UR - http://jacow.org/ipac2019/papers/mozzplm2.pdf ER - TY - CONF AU - Hirosawa, K. AU - Funakoshi, Y. AU - Koiso, H. AU - Morita, A. AU - Ohmi, K. AU - Ohnishi, Y. AU - Sugimoto, H. AU - Zhou, D. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Analysis and Correction for the Effect of Multipoles with Skewed Errors on IP Beam Dynamics in SuperKEKB J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The beam dynamics at the interaction point (IP) in the accelerators which has the nano-beam scheme like as SuperKEKB is extremely sensitive for skewed error of final focusing magnets (QCS). As proceeding the beta squeezing in the interaction region (IR), the effect of optics aberrations at IP is enhanced. In the SuperKEKB Phase-2 commissioning, there was the problem come from skewed quadrupole fields in IR. The dominant skew parameters ‘‘R" for this problem is very hard to see directly by using beam position monitors, thus it was corrected by scanning R parameters. In the next commissioning Phase-3 which is just before the operation with the Belle II experiment, it is planned that the IP beta squeezing is going forward to design parameters which is smaller than it achieved in Phase-2 by the factor of 4 (for horizontal beta) and 10 (for vertical beta). Hence the effect of skew error will be considerable larger and it is estimated that skew sextupoles will emerge as a serious cause for the aberration from the orbit. This report is the study of analysis and correction results for the effect of QCS skewed errors in the SuperKEKB commissioning. PB - JACoW Publishing CP - Geneva, Switzerland SP - 159 EP - 162 KW - luminosity KW - coupling KW - MMI KW - betatron KW - optics DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPGW031 UR - http://jacow.org/ipac2019/papers/mopgw031.pdf ER - TY - CONF AU - Du, B. AU - Liu, N. AU - Matsumoto, T. AU - Michizono, S. AU - Miura, T. AU - Qiu, F. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Design of a Compact Power Distribution System for the ILC J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The Local power distribution system (LPDS) of the In-ternational Linear Collider (ILC) is constructed to transmit RF power from the 10 MW klystron to 39 cavi-ties. Each eight or nine 9-cell cavities is assembled in one cryomodule. The variable hybrid is used to adjust the power dividing ratio due to the different required power of each cavity and the variable phase shifter is used to compensate the phase drift caused by the variable hybrid. More compact LPDS is expected to be integrated on the cryomodule decreasing financial cost. We re-design the shorter variable hybrid with a margin of power ratio of ±25% and phase shifter of total phase range being 35° for compensating hybrid and on-crest searching. Fixed phase shifters are designed to adjust the phase difference between adjacent cavities for beam acceleration. Simu-lated results of total compact LPDS can meet the re-quirements of ILC. PB - JACoW Publishing CP - Geneva, Switzerland SP - 436 EP - 438 KW - cavity KW - cryomodule KW - ECR KW - acceleration KW - collider DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPMP007 UR - http://jacow.org/ipac2019/papers/mopmp007.pdf ER - TY - CONF AU - Shimada, M. AU - Honda, Y. AU - Hotei, T. AU - Kato, R. AU - Miyajima, T. AU - Nakamura, N. AU - Obina, T. AU - Uchiyama, T. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Systematic Measurements of the Coherent THz Spectra by Magnetic Bunch Compression at the Compact ERL J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Short electron bunch beam is one of the key elements of a Free Electron Laser (FEL) or intense THz coherent light source. The Energy Recovery Linac (ERL) has the strong advantage of operation of such an electron bunch at high repetition rate and is expected to increase the photon flux. At the Compact ERL in KEK site, we have demonstrated the magnetic bunch compression at the 180-degree return arc and measured the THz spectra of the Coherent Transition Radiation (CTR). This paper reports the revamped THz beamline and the improvement of the beam tuning as well as the systematic measurements of the THz spectra by magnetic bunch compression. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1486 EP - 1488 KW - optics KW - electron KW - radiation KW - sextupole KW - linac DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPGW037 UR - http://jacow.org/ipac2019/papers/tupgw037.pdf ER - TY - CONF AU - Rehman, M.A. AU - Furukawa, K. AU - Hisamatsu, H. AU - Iinuma, H. AU - Mibe, T. AU - Nakayama, H. AU - Ohsawa, S. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Beam Control and Monitors for the Spiral Injection Test Experiment J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - A new experiment at J-PARC (E34) is under construction in order to measure the muon’s g-2 to unprecedented precision of 0.1 ppm and electric dipole moment up to the sensitivity of 10-21 e.cm in order to explore new physics beyond the standard model. A novel three-dimensional spiral injection scheme has been devised to inject and store the beam into a small diameter MRI-type storage magnet for E34. The new injection scheme features smooth injection with high storage efficiency for the compact storage magnet. However, spiral injection scheme is an unproven idea, therefore, a Spiral Injection Test Experiment (SITE) is underway to establish this injection scheme. The SITE is consist of 80 keV thermionic electron gun, two-meter-long beamline, and a solenoidal storage magnet. In order to match the beam with the solenoidal field, several optical elements have been placed on the beamline to control the beam phase space. The DC electron beam spiral track has been confirmed by the de-excitation of the nitrogen gas in the vacuum chamber of the storage magnet. A current monitor system has been developed in order to extract the beam current and geometrical information of three-dimensional trajectory. An electric chopper system to produce the pulsed beam and beam monitors to detect the pulsed beam will also be discussed in this paper. PB - JACoW Publishing CP - Geneva, Switzerland SP - 2557 EP - 2560 KW - injection KW - experiment KW - electron KW - solenoid KW - site DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-WEPGW038 UR - http://jacow.org/ipac2019/papers/wepgw038.pdf ER - TY - CONF AU - Liu, N. AU - Arakawa, D.A. AU - Du, B. AU - Katagiri, H. AU - Kobayashi, T. AU - Matsumoto, T. AU - Michizono, S. AU - Miura, T. AU - Qiu, F. AU - Yano, Y. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Development Status of RF Reference Phase Stabilization System for SuperKEKB Injector LINAC J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - SuperKEKB injector linear accelerator (LINAC) has 600 m beam lines which consist of 8 sectors. The 2856 MHz RF reference signals are distributed to each sector with long phase stabilized optical fiber (PSOF). The RF reference phase stability requirement is estimated to be 0.2°(RMS) corresponding to 200 fs. The prototype of RF reference phase stabilization system with single mode optical circulator was implemented and demonstrated in the laboratory. The returned phase drift is compensated by a piezo-driven fiber stretcher. The transmitted phase through 120 m PSOF is stabilized to 41 fs (pk-pk), which fulfilled the requirement. This paper introduces the RF reference phase stabilization system and reports the preliminary feedback result. PB - JACoW Publishing CP - Geneva, Switzerland SP - 3879 EP - 3881 KW - linac KW - controls KW - feedback KW - photon KW - distributed DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-THPRB033 UR - http://jacow.org/ipac2019/papers/thprb033.pdf ER -