183 research outputs found
Tracking simulations and optimization of the CLIC injector linac
No full textThe CLIC positron source has been designed to produce non-polarized positrons for the first stage of CLIC at 380 GeV. In the CLIC positron source, the injector linac is supposed to accelerate positron beams and electron beams simultaneously from 200 MeV after the pre-injectors up to the damping ring energy of 2.86 GeV. The optics design of the injector linac has been done for the positrons since the emittance of the positron beam is much larger compared to the electron beam. This study presents new particle tracking simulations and an optimization of the CLIC injector linac for the positrons. In addition, beam offset and quadrupole misalignment errors have been investigated in the CLIC injector linac
Spectrometry in the Test Beam Line at CTF3
No full textThe CLIC study is based on the so-called two-beam acceleration concept and one of the main goals of the CLIC Test Facility 3 is to demonstrate the efficiency of the CLIC RF power production scheme. As part of this facility a Test Beam Line (TBL), presently under commissioning, is a small-scale version of a CLIC decelerator. To perform as expected the beam line must show efficient and stable RF power production over 16 consecutive decelerating structures. As the high intensity electron beam is decelerated its energy spread grows by up to 60 %. A novel segmented beam dump for time resolved energy measurements has been designed to match the requirements of the TBL. As a complement, a diffusive OTR screen is also installed in the same spectrometer line. The combination of these two devices will provide both a high spatial resolution measurement of both the energy and energy spread and a measurement with a few nanoseconds time response. This paper describes the design of the new segmented dump and presents the results from the first commissioning of the TBL spectrometer line
Production of long bunch trains with 4.5muC total charge using a photoinjector
No full textA photoinjector, PHIN (PHotoINjector), has been realized at CERN by a joint effort of several institutes within the European Coordinated Accelerator Research in Europe program. The test facility has been installed and commissioned at CERN with the aim to demonstrate the beam parameters needed for the CLIC Test Facility 3 (CTF3). This beam is unique with respect to its long bunch train and high average charge per bunch requirements. The nominal beam for CTF3 consists of 1908 bunches each having a 2.33 nC charge and a bunch frequency of 1.5 GHz. Thus, a total charge of ∼4.4 μC has to be extracted and accelerated. The stability of the intensity and the beam parameters along this exceptionally high average current train is crucial for the correct functioning of the CLIC drive beam scheme. Consequently, extensive time-resolved measurements of the transverse and longitudinal beam parameters have been developed, optimized, and performed. The shot-to-shot intensity stability has been studied in detail for the electron and the laser beams, simultaneously. The PHIN photoinjector has been commissioned between 2008 and 2010 during intermittent operations. This paper reports on the obtained results in order to demonstrate the feasibility and the stability of the required beam parameters
The AWAKE Run 2 programme and beyond
No full textAutores: Edda Gschwendtner, Konstantin Lotov, Patric Muggli, Matthew Wing, Riccardo Agnello, Claudia Christina Ahdida, Maria Carolina Amoedo Goncalves, Yanis Andrebe, Oznur Apsimon, Robert Apsimon, Jordan Matias Arnesano, Anna-Maria Bachmann, Diego Barrientos, Fabian Batsch, Vittorio Bencini, Michele Bergamaschi, Patrick Blanchard, Philip Nicholas Burrows, Birger Buttenschön, Allen Caldwell, James Chappell, Eric Chevallay, Moses Chung, David Andrew Cooke, Heiko Damerau, Can Davut, Gabor Demeter, Amos Christopher Dexter, Steffen Doebert, Francesa Ann Elverson, John Farmer, Ambrogio Fasoli, Valentin Fedosseev, Ricardo Fonseca, Ivo Furno, Spencer Gessner, Aleksandr Gorn, Eduardo Granados, Marcel Granetzny, Tim Graubner, Olaf Grulke, Eloise Daria Guran, Vasyl Hafych, Anthony Hartin, James Henderson, Mathias Hüther, Miklos Kedves, Fearghus Keeble, Vadim Khudiakov, Seong-Yeol Kim, Florian Kraus, Michel Krupa, Thibaut Lefevre, Linbo Liang, Shengli Liu, Nelson Lopes, Miguel Martinez Calderon, Stefano Mazzoni, David Medina Godoy, Joshua Moody, Kookjin Moon, Pablo Israel Morales Guzmán, Mariana Moreira, Tatiana Nechaeva, Elzbieta Nowak, Collette Pakuza, Harsha Panuganti, Ans Pardons, Kevin Pepitone, Aravinda Perera, Jan Pucek, Alexander Pukhov, Rebecca Louise Ramjiawan, Stephane Rey, Adam Scaachi, Oliver Schmitz, Eugenio Senes, Fernando Silva, Luis Silva, Christine Stollberg, Alban Sublet, Catherine Swain, Athanasios Topaloudis, Nuno Torrado, Petr Tuev, Marlene Turner, Francesco Velotti, Livio Verra, Victor Verzilov, Jorge Vieira, Helmut Vincke, Martin Weidl, Carsten Welsch, Manfred Wendt, Peerawan Wiwattananon, Joseph Wolfenden, Benjamin Woolley, Samuel Wyler, Guoxing Xia, Vlada Yarygova, Michael Zepp, Giovanni Zevi Della Porta. ::: Publisher: [MDPI] ::: Location: [
Latest Developments from the S-DALINAC*
No full textThe S-DALINAC is a 130 MeV superconducting recirculating electron accelerator serving several nuclear and radiation physics experiments as well as driving an infrared free-electron laser. A system of normal conducting rf resonators for noninvasive beam position and current measurement was established. For the measurement of gamma-radiation inside the accelerator cave a system of Compton diodes has been developed and tested. Detailed investigations of the transverse phasespace were carried out with a tomographical reconstruction method of optical transition radiation spots. The method can be applied also to non-Gaussian phasespace distributions. The results are in good accordance with simulations. To improve the quality factor of the superconducting 3 GHz cavities, an external 2K testcryostat was commissioned. The influence of electro-chemical polishing and magnetic shielding is currently under investigation. A digital rf-feedback-system for the accelerator cavities is being developed in order to improve the energy spread of the beam of the S-DALINAC. * Supported by the BMBF under contract no. 06 DA 820, the DFG under contract no. Ri 242/12-1 and -2 and the DFG Graduiertenkolleg 'Physik und Technik von Beschleunigern'The S-DALINAC is a 130 MeV superconducting recirculating electron accelerator serving several nuclear and radiation physics experiments as well as driving an infrared free-electron laser. A system of normal conducting rf resonators for noninvasive beam position and current measurement was established. For the measurement of gamma-radiation inside the accelerator cave a system of Compton diodes has been developed and tested. Detailed investigations of the transverse phasespace were carried out with a tomographical reconstruction method of optical transition radiation spots. The method can be applied also to non-Gaussian phasespace distributions. The results are in good accordance with simulations. To improve the quality factor of the superconducting 3 GHz cavities, an external 2K testcryostat was commissioned. The influence of electro-chemical polishing and magnetic shielding is currently under investigation. A digital rf-feedback-system for the accelerator cavities is being developed in order to improve the energy spread of the beam of the S-DALINAC. * Supported by the BMBF under contract no. 06 DA 820, the DFG under contract no. Ri 242/12-1 and -2 and the DFG Graduiertenkolleg 'Physik und Technik von Beschleunigern
Low emittance design of the electron gun and the focusing channel of the Compact Linear Collider drive beam
No full textFor the Compact Linear Collider project at CERN, the power for the main linacs is extracted from a drive beam generated from a high current electron source. The design of the electron source and its subsequent focusing channel has a great impact on the beam dynamic considerations of the drive beam. We report the design of a thermionic electron source and the subsequent focusing channels with the goal of production of a high quality beam with a very small emittance
Beam dynamics design of the Compact Linear Collider Drive Beam injector
No full textIn the Compact Linear Collider (CLIC) the RF power for the acceleration of the Main Beam is extracted from a high-current Drive Beam that runs parallel to the main linac. The longitudinal and transverse beam dynamics of the Drive Beam injector has been studied in detail and optimized. The injector consists of a thermionic gun followed by a bunching system, some accelerating structures, and a magnetic chicane. The bunching system contains three sub-harmonic bunchers, a prebuncher, and a traveling wave buncher all embedded in a solenoidal magnetic field. The main characteristic of the Drive Beam injector is the phase coding process done by the sub-harmonic bunching system operating at half the acceleration frequency. This process is essential for the frequency multiplication of the Drive Beam. During the phase coding process the unwanted satellite bunches are produced that adversely affects the machine power efficiency. The main challenge is to reduce the population of particles in the satellite bunches in the presence of strong space-charge forces due to the high beam current. The simulation of the beam dynamics has been carried out with parmela with the goal of optimizing the injector performance compared to the existing model studied for the Conceptual Design Report (CDR). The emphasis of the optimization was on decreasing the satellite population, the beam loss in the magnetic chicane and limiting the beam emittance growth in transverse plane
Six-Dimensional Beam-Envelope Equations: An Ultrafast Computational Approach for Interactive Modeling of Accelerator Structures
No full textThe design and implementation of accelerators capable of providing high-quality bunches require precise and efficient online modeling tools. Current comprehensive beam dynamics studies are prohibitively costly and challenging to use for interactive system design. A precise high-speed method for beam dynamics analysis in accelerator components is presented and compared to the results of the conventional particle-in-cell codes. Using powerful mathematical techniques, the suggested method evaluates the temporal evolution of a bunch shape in six-dimensional (6D) phase space along the accelerators. The moment equations that govern the evolution of the bunch envelope in 6D phase space are introduced. The three-dimensional space-charge, external, and emittance forces are calculated to be fully analytically insensitive to different beam envelopes. Substituting the obtained forces into the beam-envelope equations establishes a set of six modified equations describing the beam dynamics using simple algebraic expressions. The whole solution considers the energy spread inherent to an electron beam. The model accuracy is demonstrated by studying beam transport through various components of an accelerator. Applying this analytical approach not only forms a style of physical thinking by indicating the factors that affect the behavior of the charged particle bunches but also has an ultrafast computational speed that is at least 3 orders of magnitude faster than that of particle tracking codes for designing today’s linear accelerators. Finally, the model’s feasibility is benchmarked for successfully designing a photoinjector for the advanced proton driven plasma wakefield acceleration experiment
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