TY - CONF AU - Galyamin, S.N. AU - Benediktovitch, A.I. AU - Tyukhtin, A.V. AU - Vorobev, V.V. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Radiation of a Charge Moving in a Wire Structure J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - In the X-ray frequency region, interaction of relativistic electrons with crystals results in parametric X-ray radiation (PXR), with its frequency being determined by distance between crystallographic planes and direction of electron motion. If instead of crystal one considers an artificial periodic structure with periods of the order of mm, one can expect emission of radiation of a similar nature at terahertz (THz) frequencies. This frequency range is of significant interest during last decade due to its prospective applications. Moreover, artificial wire-like structures are considered as a promising alternative to conventional dielectric structures for wakefield acceleration*. Here we consider electromagnetic (EM) field produced by a charged particle bunch moving through a lattice of parallel conducting wires. We present several approaches for analysis of EM field in the described wire structure. First, conventional two-wave approximation for describing the "short-wave response" is developed. Second, we use the effective medium approach and describe the "long-wave" part of the spectrum. Third, we develop a method based on vibrator antenna theory which can be useful for finite length wire structure. PB - JACoW Publishing CP - Geneva, Switzerland SP - 231 EP - 233 KW - radiation KW - FEL KW - simulation KW - lattice KW - electron DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPGW062 UR - http://jacow.org/ipac2019/papers/mopgw062.pdf ER - TY - CONF AU - Tomin, S. AU - Fröhlich, L. AU - Scholz, M. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Status of Automated Optimization Procedures at the European XFEL Accelerator J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The European XFEL is in the operational stage since fall 2017. Since then, tuning of the FEL performance (e.g. of the photon pulse energy) has become increasingly important. Due to a large number of parameters to which FEL facilities are highly sensitive and their complex correlations, controlling and optimizing them in a speedy manner is becoming a very important and challenging task. Several automated optimization procedures were developed to optimize the FEL beam quality. In this work, we present the status and the results of these activities, as well as the optimization statistics. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1212 EP - 1215 KW - FEL KW - feedback KW - electron KW - undulator KW - status DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUZZPLM2 UR - http://jacow.org/ipac2019/papers/tuzzplm2.pdf ER - TY - CONF AU - White, G.R. AU - Cobb, T.M. AU - Dalesio, L.R. AU - Davidsaver, M.A. AU - Hartman, S.M. AU - Hickin, D.G. AU - Johnson, A.N. AU - Junkes, H. AU - Kasemir, K.-U. AU - Konrad, M.G. AU - Korhonen, T. AU - Kraimer, M.R. AU - Lange, R. AU - Pearson, M.R. AU - Rivers, M.L. AU - Sekoranja, M. AU - Shankar, M.V. AU - Shen, G. AU - Shroff, K. AU - Veseli, S. AU - Vodopivec, K. AU - Zimoch, D. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - The EPICS Software Framework Moves from Controls to Physics J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The Experimental Physics and Industrial Control System (EPICS), is an open-source software framework for high-performance distributed control, and is at the heart of many of the world’s large accelerators and telescopes. Recently, EPICS has undergone a major revision, with the aim of better computing supporting for the next generation of machines and analytical tools. Many new data types, such as matrices, tables, images, and statistical descriptions, plus users’ own data types, now supplement the simple scalar and waveform types of the former EPICS. New computational architectures for scientific computing have been added for high-performance data processing services and pipelining. Python and Java bindings have enabled powerful new user interfaces. The result has been that controls are now being integrated with modelling and simulation, machine learning, enterprise databases, and experiment DAQs. We introduce this new EPICS (version 7) from the perspective of accelerator physics and review early adoption cases in accelerators around the world. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1216 EP - 1218 KW - EPICS KW - controls KW - detector KW - database KW - experiment DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUZZPLM3 UR - http://jacow.org/ipac2019/papers/tuzzplm3.pdf ER - TY - CONF AU - Liu, S. AU - Li, Y. AU - Wolff-Fabris, F. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Undulator Radiation Dose Caused by Synchrotron Radiation at the European XFEL J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Radiation damage of the undulators is a big concern for the light sources. At the European XFEL (EuXFEL), dosimeters based on on-line Radfets are used for the un-dulator radiation dose measurements. However, since the Radfets are not only sensitive to the electrons and neu-trons but also to the photons, it can capture the synchro-tron radiation (SR) generated in the undulators, which is not considered to be the main source for undulator radia-tion damage. Therefore, it is important to estimate the contribution of synchrotron radiation to the radiation doses measured by the Radfets. For this purpose, we have first calculated the synchrotron radiation profile using SPECTRA, and then put the profile into the tracking code BDSIM to track it through the whole undulator beam line. The radiation doses from SR have been simulated and compared with the measured values. The differences in the radiation doses measured by the Radfets before and after Pb shielding will also be presented. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1724 EP - 1727 KW - undulator KW - radiation KW - FEL KW - simulation KW - vacuum DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB021 UR - http://jacow.org/ipac2019/papers/tuprb021.pdf ER - TY - CONF AU - Schneidmiller, E. AU - Balandin, V. AU - Decking, W. AU - Dohlus, M. AU - Geloni, G. AU - Golubeva, N. AU - Li, Y. AU - Molodtsov, S. AU - Nölle, D. AU - Pflüger, J. AU - Serkez, S. AU - Sinn, H. AU - Tanikawa, T. AU - Tomin, S. AU - Yurkov, M.V. AU - Zagorodnov, I. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Considerations for the Ultrahard X-ray Undulator Line of the European XFEL J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The European XFEL is a multi-user X-ray FEL facility based on superconducting linear accelerator. Presently, three undulators (SASE1, SASE2, SASE3) routinely deliver high-brightness soft- and hard- X-ray beams for users. There are two empty undulator tunnels that were originally designed to operate with spontaneous radiators in the range 20-90 keV. We consider, instead a possible installation of two FEL undulators. One of them (SASE4) is proposed for operation in a standard (7-25 keV) range as well as in ultrahard (25-100 keV) regime. We discuss a possible location and length of SASE4, modifications of electron beam transport, beam dynamics, choice of undulator technology, different operation modes (SASE and advanced lasing concepts) etc. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1732 EP - 1735 KW - undulator KW - FEL KW - photon KW - electron KW - operation DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB023 UR - http://jacow.org/ipac2019/papers/tuprb023.pdf ER - TY - CONF AU - Schneidmiller, E. AU - Brinker, F. AU - Decking, W. AU - Gerasimova, N. AU - Grünert, J. AU - Kujala, N.G. AU - Laksman, J. AU - Li, Y. AU - Liu, J. AU - Maltezopoulos, Th. AU - Nölle, D. AU - Petrov, I. AU - Samoylova, L. AU - Serkez, S. AU - Sinn, H. AU - Wolff-Fabris, F. AU - Yurkov, M.V. AU - Zagorodnov, I. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Harmonic Lasing of the European XFEL in the Angstrom Regime J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Harmonic lasing in XFELs is an opportunity to extend the photon energy range of existing and planned X-ray FEL user facilities. Contrary to nonlinear harmonic generation, harmonic lasing can provide much more intense, stable, and narrow-band FEL beam. Another interesting application is Harmonic Lasing Self-Seeding (HLSS) that allows to improve longitudinal coherence and spectral power of a Self-Amplified Spontaneous Emission (SASE) FEL. This concept was successfully tested at FLASH2 in the range of 4.5 - 15 nm and at PAL XFEL at 1 nm. In this contribution we present recent results from the European XFEL where we successfully demonstrated operation of HLSS FEL at 5.9 A, thus pushing harmonic lasing for the first time into the Angstrom regime. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1740 EP - 1743 KW - FEL KW - undulator KW - photon KW - experiment KW - operation DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB025 UR - http://jacow.org/ipac2019/papers/tuprb025.pdf ER - TY - CONF AU - Halavanau, A. AU - Benediktovitch, A.I. AU - Pellegrini, C. AU - Rohringer, N. AU - Wu, J. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Preliminary Considerations of Atomic Inner-Shell X-Ray Laser for Self-Seeding at LCLS-II J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The atomic inner-shell X-ray lasing, induced by the irradiation of focused XFEL SASE pulses, was demonstrated in gases, liquid jets and solids. In this proceeding, we discuss the possible use of this concept in self-seeding scheme at LCLS-II. We provide a preliminary study of different lasing media and corresponding SASE XFEL parameters. For the case of noble gas inner-shell X-ray laser, we study the requirements for gas pressure and XFEL pulse focusing. Finally, we discuss possible designs of this system and its advantages in LCLS-II operations. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1871 EP - 1874 KW - FEL KW - photon KW - simulation KW - radiation KW - experiment DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB090 UR - http://jacow.org/ipac2019/papers/tuprb090.pdf ER - TY - CONF AU - Halavanau, A. AU - Benediktovitch, A.I. AU - Gurnevich, E.A. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Cherenkov Radiation in Periodic Wire Medium Formed by Transversely Modulated Electron Beams J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - We investigate the properties of Cherenkov, quasi-Cherenkov (parametric) and diffraction radiation generated in the periodic conducting wire medium by transversely modulated electron beams. Such beams were recently obtained at Argonne Wakefield Accelerator (AWA) facility using microlens array (MLA) laser shaping technique. We consider in details the case of one dimensional periodic tungsten wire structure and transverse electron beamlets separation of mm scale. We look at possible enhancements of the radiation field due to transverse periodicity of the electron beam. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1878 EP - 1880 KW - radiation KW - electron KW - laser KW - cathode KW - experiment DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPRB092 UR - http://jacow.org/ipac2019/papers/tuprb092.pdf ER - TY - CONF AU - Tomin, S. AU - Geloni, G. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Synchrotron Radiation Module in OCELOT Toolkit J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Synchrotron radiation (SR) sources based on single-pass accelerators (e.g. linacs, plasma accelerators) have to cope with electron beams with a rather complicated phase space distribution. In this case, the convolution method usually employed to calculate radiation properties can give poor accuracy or be not applicable at all. Moreover, dynamical effects can also play a role in the emission mechanism. This happens when the beam parameters (e.g. beam current) significantly change during the passage through the undulator. In this work, we present a dedicated SR module of the OCELOT toolkit, which is well suited to deal with these situations. PB - JACoW Publishing CP - Geneva, Switzerland SP - 3127 EP - 3129 KW - electron KW - undulator KW - radiation KW - simulation KW - FEL DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-WEPTS017 UR - http://jacow.org/ipac2019/papers/wepts017.pdf ER - TY - CONF AU - Syresin, E. AU - Brovko, O.I. AU - Freund, W. AU - Grebentsov, A.Yu. AU - Grünert, J. AU - Yurkov, M.V. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - MCP Based Detectors of European XFEL J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Radiation detectors based on microchannel plates (MCP) are used for measurements of the SASE process of the European XFEL. Detectors operate in a wide dynamic range from the level of spontaneous emission to the saturation level (between a few nJ and 25 mJ) and in a wide wavelength range from 0.05 nm to 0.4 nm for SASE1 and SASE2 and from 0.4 nm to 4.43 nm for SASE3. Photon pulse energies are measured by the MCPs with an anode and by a photodiode. The MCP imager measures the photon beam image with a phosphor screen. Three MCP detectors are installed, one behind each SASE undulator (SASE1, SASE2, and SASE3). Calibration and first experiments with the MCP detectors are under discussion. PB - JACoW Publishing CP - Geneva, Switzerland SP - 3703 EP - 3705 KW - FEL KW - detector KW - photon KW - radiation KW - electron DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-THPGW051 UR - http://jacow.org/ipac2019/papers/thpgw051.pdf ER -