18 results on '"Citterio, Alessandro"'
Search Results
2. Multi-objective shape optimization of radio frequency cavities using an evolutionary algorithm
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Kranjcevic, Marija, Adelmann, Andreas, Arbenz, Peter, Citterio, Alessandro, and Stingelin, Lukas
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Physics - Accelerator Physics - Abstract
Radio frequency (RF) cavities are commonly used to accelerate charged particle beams. The shape of the RF cavity determines the resonant electromagnetic fields and frequencies, which need to satisfy a variety of requirements for a stable and efficient acceleration of the beam. For example, the accelerating frequency has to match a given target frequency, the shunt impedance usually has to be maximized, and the interaction of higher order modes with the beam minimized. In this paper we formulate such problems as constrained multi-objective shape optimization problems, use a massively parallel implementation of an evolutionary algorithm to find an approximation of the Pareto front, and employ a penalty method to deal with the constraint on the accelerating frequency. Considering vacuated axisymmetric RF cavities, we parameterize and mesh their cross section and then solve time-harmonic Maxwell's equations with perfectly electrically conducting boundary conditions using a fast 2D Maxwell eigensolver. The specific problem we focus on is the hypothetical problem of optimizing the shape of the main RF cavity of the planned upgrade of the Swiss Synchrotron Light Source (SLS), called SLS-2. We consider different objectives and geometry types and show the obtained results, i.e. the computed Pareto front approximations and the RF cavity shapes with desired properties. Finally, we compare these newfound cavity shapes with the current cavity of SLS.
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- 2018
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3. A compact and cost-effective hard X-ray free-electron laser driven by a high-brightness and low-energy electron beam
- Author
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Prat, Eduard, Abela, Rafael, Aiba, Masamitsu, Alarcon, Arturo, Alex, Jürgen, Arbelo, Yunieski, Arrell, Christopher, Arsov, Vladimir, Bacellar, Camila, Beard, Carl, Beaud, Paul, Bettoni, Simona, Biffiger, Roger, Bopp, Markus, Braun, Hans-Heinrich, Calvi, Marco, Cassar, Ariana, Celcer, Tine, Chergui, Majed, Chevtsov, Pavel, Cirelli, Claudio, Citterio, Alessandro, Craievich, Paolo, Divall, Marta Csatari, Dax, Andreas, Dehler, Micha, Deng, Yunpei, Dietrich, Alexander, Dijkstal, Philipp, Dinapoli, Roberto, Dordevic, Sladana, Ebner, Simon, Engeler, Daniel, Erny, Christian, Esposito, Vincent, Ferrari, Eugenio, Flechsig, Uwe, Follath, Rolf, Frei, Franziska, Ganter, Romain, Garvey, Terence, Geng, Zheqiao, Gobbo, Alexandre, Gough, Christopher, Hauff, Andreas, Hauri, Christoph P., Hiller, Nicole, Hunziker, Stephan, Huppert, Martin, Ingold, Gerhard, Ischebeck, Rasmus, Janousch, Markus, Johnson, Philip J. M., Johnson, Steven L., Juranić, Pavle, Jurcevic, Mario, Kaiser, Maik, Kalt, Roger, Keil, Boris, Kiselev, Daniela, Kittel, Christoph, Knopp, Gregor, Koprek, Waldemar, Laznovsky, Michael, Lemke, Henrik T., Sancho, Daniel Llorente, Löhl, Florian, Malyzhenkov, Alexander, Mancini, Giulia Fulvia, Mankowsky, Roman, Marcellini, Fabio, Marinkovic, Goran, Martiel, Isabelle, Märki, Fabian, Milne, Christopher J., Mozzanica, Aldo, Nass, Karol, Orlandi, Gian Luca, Loch, Cigdem Ozkan, Paraliev, Martin, Patterson, Bruce, Patthey, Luc, Pedrini, Bill, Pedrozzi, Marco, Pradervand, Claude, Radi, Peter, Raguin, Jean-Yves, Redford, Sophie, Rehanek, Jens, Reiche, Sven, Rivkin, Leonid, Romann, Albert, Sala, Leonardo, Sander, Mathias, Schietinger, Thomas, Schilcher, Thomas, Schlott, Volker, Schmidt, Thomas, Seidel, Mike, Stadler, Markus, Stingelin, Lukas, Svetina, Cristian, Treyer, Daniel M., Trisorio, Alexandre, Vicario, Carlo, Voulot, Didier, Wrulich, Albin, Zerdane, Serhane, and Zimoch, Elke
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- 2020
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4. Multi-objective shape optimization of radio frequency cavities using an evolutionary algorithm
- Author
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Kranjčević, Marija, Adelmann, Andreas, Arbenz, Peter, Citterio, Alessandro, and Stingelin, Lukas
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- 2019
- Full Text
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5. CLUSTER: a high frequency H-mode coupled cavity linac for low and medium energies
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Amaldi, Ugo, Citterio, Alessandro, Crescenti, Massimo, Giuliacci, Arianna, Tronci, Cesare, and Zennaro, Riccardo
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Physics - Accelerator Physics ,Physics - Medical Physics - Abstract
We propose an innovative linear accelerating structure, particularly suited for hadrontherapy applications. Its two main features are compactness and good power efficiency at low beam velocities: the first is achieved through a high working frequency and a consequent high accelerating gradient, the second is obtained by coupling several H-mode cavities together. The structure is called CLUSTER, which stands for "Coupled-cavity Linac USing Transverse Electric Radial field". In order to compare the performance of this structure with other hadrontherapy linac designs involving high frequencies, a conceptual study has been performed for an operating frequency of 3 GHz. Moreover a proof of principle has been obtained through RF measurements on a prototype operating at 1 GHz. An accelerator complex using a CLUSTER linac is also considered for protontherapy purposes. The whole complex is called cyclinac and is composed of a commercial cyclotron injecting the beam in a high-frequency linac., Comment: for submission to Nucl. Instr. Meth. A
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- 2006
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6. SwissFEL double bunch operation
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Paraliev, Martin, primary, Alarcon, Arturo, additional, Arsov, Vladimir, additional, Bettoni, Simona, additional, Biffiger, Roger, additional, Boll, Marco, additional, Braun, Hans, additional, Citterio, Alessandro, additional, Craievich, Paolo, additional, Dax, Andreas Josef, additional, Dijkstal, Philipp, additional, Dordevic, Sladana, additional, Ferrari, Eugenio, additional, Frei, Franziska, additional, Ganter, Romain, additional, Geng, Zheqiao, additional, Gough, Christopher, additional, Hiller, Nicole, additional, Huppert, Martin, additional, Ischebeck, Rasmus, additional, Juranic, Pavle, additional, Jurcevic, Mario, additional, Kalantari, Babak, additional, Kalt, Roger, additional, Keil, Boris, additional, Kittel, Christoph, additional, Koprek, Waldemar, additional, Llorente, Daniel, additional, Löhl, Florian, additional, Malyzhenkov, Alexander, additional, Marcellini, Fabio, additional, Marinkovic, Goran, additional, Orlandi, Gian Luca, additional, Ozkan Loch, Cigdem, additional, Pedrozzi, Marco, additional, Prat, Eduard, additional, Reiche, Sven, additional, Rosenberg, Colette, additional, Schietinger, Thomas, additional, Sidorov, Serguei, additional, Trisorio, Alexandre, additional, Vicario, Carlo, additional, Voulot, Didier, additional, Wang, Guanglei, additional, and Zennaro, Riccardo, additional
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- 2022
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7. CLUSTER: A high-frequency H-mode coupled cavity linac for low and medium energies
- Author
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Amaldi, Ugo, Citterio, Alessandro, Crescenti, Massimo, Giuliacci, Arianna, Tronci, Cesare, and Zennaro, Riccardo
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- 2007
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8. Characterization of NEG Coatings for SLS 2.0
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Dehler, Micha, Alberti, Stefano, Citterio, Alessandro, Hahn, Michael, Hogge, Jean-Philippe, Liu, Xiaoyu, Marques, Hugo, and European Synchrotron Radiation Facility (ESRF)
- Subjects
MC7: Accelerator Technology ,resonance ,[PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph] ,vacuum ,GUI ,impedance ,coupling ,Accelerator Physics - Abstract
To limit desorption and ameliorate pumping of the narrow 20 mm aperture vacuum chamber of SLS2.0, it is planned to fully coat it with nonevaporable getter (NEG) material. NEG coating can be produced with different structural characteristics, from dense films to columnar growth, with corresponding distinct electrical properties affecting the machine impedance and the instability threshold of the accelerator. In order to evaluate and characterize the coating process for geometries similar to the SLS chamber, we measured the resonance properties of coated and uncoated shorted waveguide pieces. First tests were done with standard X band waveguides at 12 and 7 GHz. Test setups using elliptical cross sections are in preparation, also for higher frequencies allowing the characterization of thin NEG layers. The final goal is to have a standardized process to test of samples coated by external producers. We describe the setups and first results., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia
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- 2019
9. Exploring the Potential of the Swiss Light Source
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Aiba, Masamitsu, Böge, Michael, Citterio, Alessandro, Dehler, Micha, Lüdeke, Andreas, Ozkan Loch, Cigdem, Stingelin, Lukas, and Streun, Andreas
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Physics::Accelerator Physics ,MC2: Photon Sources and Electron Accelerators ,Accelerator Physics - Abstract
Swiss Light Source (SLS) has been on-line since 2001. Although its performance meets the specifications, it still has a potential to achieve better storage ring beam parameters. We explore two possible improvements. The first one is for the beam lifetime. There are 480 rf buckets while normally 390 bunches are stored. The gap in filing pattern (90 empty buckets) is held to suppress ion instability. After many years of operation, however, the vacuum condition is much better than that of the time when the SLS was turned on. Hence it is possible to shorten the gap. The beam lifetime can then be prolonged due to less bunch current while keeping the net beam current. The study may be also useful to predict possible filling patter in SLS2, which is the SLS upgrade planned. The second one is for the beam emittance. The nominal energy closed orbit coincides with the axes of quadrupole magnets. An off-momentum closed orbit is therefore off-centered through quadrupoles, resulting in a damping partition shift. The beam emittance can be decreased at the expense of a larger energy spread. This was successfully achieved in the ESRF booster. We study whether it is applicable to the SLS storage ring., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia
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- 2019
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10. Overview of Collective Effects in SLS 2.0
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Dehler, Micha, Aiba, Masamitsu, Citterio, Alessandro, and Stingelin, Lukas
- Subjects
Physics::Accelerator Physics ,MC2: Photon Sources and Electron Accelerators ,Accelerator Physics - Abstract
At the end of 2017, the conceptual design for an upgrade of the Swiss Light Source was finished, promising a 40 fold smaller emittance and a corresponding increase of the spectral brightness from the current value. From the point of view of collective effects, the main changes in the new design are a reduced chamber size, fully coated with NEG, and operation at small and negative momentum compaction with low synchrotron frequency. We give an overview of the latest results for the ring. Most critical is the threshold for the longitudinal single bunch instability. Taking into account the combined effect of wake impedances and CSR, we have to rely on bunch stretching by a higher harmonic system to achieve stable operation at nominal current., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia
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- 2019
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11. The PolariX-TDS Project: Bead-Pull Measurements and High-Power Test on the Prototype
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Craievich, Paolo, Aßmann, Ralph, Bopp, Markus, Braun, Hans-Heinrich, Catalán Lasheras, Nuria, Christie, Florian, Citterio, Alessandro, D'Arcy, Richard, Dorda, Ulrich, Foese, Manon, Ganter, Romain, Gonzalez Caminal, Pau, Grudiev, Alexej, Hoffmann, Matthias, Hüning, Markus, Jonas, Rolf, Kleeb, Thomas, Krebs, Olaf, Lederer, Sven, Libov, Vladyslav, Marcellini, Fabio, Marchetti, Barbara, Marx, Daniel, McMonagle, Gerard, Millar, William, Osterhoff, Jens, Pedrozzi, Marco, Pitman, Sam, Prat, Eduard, Reiche, Sven, Reukauff, Matthias, Schlarb, Holger, Schreiber, Siegfried, Szypula, Kamil, Tews, Gerd, Vogt, Mathias, Wagner, Antonio De Zubiaurre, Wuensch, Walter, and Del Pozo Romano, Veronica
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Physics::Optics ,Physics::Accelerator Physics ,Electron Diagnostics, Timing, Synchronization, and Controls ,Accelerators and Storage Rings ,Accelerator Physics - Abstract
39th International Free-Electron Laser Conference, FEL19, Hamburg, Germany, 26 Aug 2019 - 30 Aug 2019; JACoW Publishing, Geneva, Switzerland 396-399 (2019). doi:10.18429/JACOW-FEL2019-WEP036, A collaboration between DESY, PSI and CERN has been established to develop and build an advanced modular X- band transverse deflection structure (TDS) system with the new feature of providing variable polarization of the deflecting force. The prototype of the novel X-band TDS, the Polarizable X-band (PolariX) TDS, was fabricated at PSI following the high-precision tuning-free production process developed for the C-band Linac of the SwissFEL project. Bead-pull RF measurements were also performed at PSI to verify, in particular, that the polarization of the dipole fields does not have any rotation along the structure. The high-power test was performed at CERN and now the TDS is at DESY and has been installed in FLASHForward, where the first streaking experience with beam will be accomplished. We summarize in this paper the status of the project, the results of the bead-pull measurements and the high power test., Published by JACoW Publishing, Geneva, Switzerland
- Published
- 2019
12. Conceptual Design for SLS-2
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Dehler, Micha, Citterio, Alessandro, Garvey, Terence, Hahn, Michael, Negrazus, Marco, Schulz, Lothar, Streun, Andreas, and Vranković, Vjeran
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Physics::Accelerator Physics ,B - Ring-based Light Sources ,Accelerator Physics - Abstract
After 17 years of user operation, we plan to do an upgrade of the Swiss Light Source (SLS) for the period of 2021-2024. The entire storage ring will be replaced with a new layout allowing operation at emittances lowered by factors of 40-50. This is made possible to one part by small aperture magnets allowing for a multi bend achromat design and to the other - a special feature for SLS-2 - reverse bends combined with longitudinal gradient bends (LGB) leading to zero dispersion at the maximum magnetic field, thus minimizing the quantum excitation of the beam due to synchrotron radiation. The compact magnet layout makes use of offset quadrupoles, combined function magnets and longitudinal gradient bends. The chamber with a cross section of 20 mm will be fully NEG coated to ensure good pumping and a quick vacuum conditioning. Numerical simulation of instability thresholds has been performed, we expect values in the order of 2 mA for the single bunch current., Proceedings of the 60th ICFA Advanced Beam Dynamics Workshop on Future Light Sources, FLS2018, Shanghai, China
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- 2018
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13. Consolidation and Extension of the High-gradient LINAC RF Technology at PSI
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Craievich, Paolo, Bopp, Markus, Braun, Hans-Heinrich, Citterio, Alessandro, Fitze, Hansruedi, Garvey, Terence, Kleeb, Thomas, Löhl, Florian, Marcellini, Fabio, Pedrozzi, Marco, Raguin, Jean-Yves, Rivkin, Leonid, Rolli, Kilian, and Zennaro, Riccardo
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Technology ,Accelerator Physics - Abstract
For SwissFEL a novel production process for high-gradient, high-precision C-band accelerating structures had been developed at PSI and was implemented for series production in collaboration with industry. The copper parts of the structures are machined and brazed relying on a ultra-high precision manufacturing process and tight mechanical tolerances; no RF tuning methods are applied during or after production. So far none of the structures of the series production failed during RF power conditioning and operation in the SwissFEL facility. After completing the series production for SwissFEL PSI started collaborations with CERN, ELETTRA and DESY for applying the production process and related know-how to other frequencies, namely S-band (3 GHz) and X-band (12 GHz). This paper gives an overview on the ongoing and planned R\&D activities and results obtained so far., Proceedings of the 29\textsuperscript{th} Linear Accelerator Conf., LINAC2018, Beijing, China
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- 2018
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14. SwissFEL: The Swiss X-ray Free Electron Laser
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Milne, Christopher, primary, Schietinger, Thomas, additional, Aiba, Masamitsu, additional, Alarcon, Arturo, additional, Alex, Jürgen, additional, Anghel, Alexander, additional, Arsov, Vladimir, additional, Beard, Carl, additional, Beaud, Paul, additional, Bettoni, Simona, additional, Bopp, Markus, additional, Brands, Helge, additional, Brönnimann, Manuel, additional, Brunnenkant, Ingo, additional, Calvi, Marco, additional, Citterio, Alessandro, additional, Craievich, Paolo, additional, Csatari Divall, Marta, additional, Dällenbach, Mark, additional, D’Amico, Michael, additional, Dax, Andreas, additional, Deng, Yunpei, additional, Dietrich, Alexander, additional, Dinapoli, Roberto, additional, Divall, Edwin, additional, Dordevic, Sladana, additional, Ebner, Simon, additional, Erny, Christian, additional, Fitze, Hansrudolf, additional, Flechsig, Uwe, additional, Follath, Rolf, additional, Frei, Franziska, additional, Gärtner, Florian, additional, Ganter, Romain, additional, Garvey, Terence, additional, Geng, Zheqiao, additional, Gorgisyan, Ishkhan, additional, Gough, Christopher, additional, Hauff, Andreas, additional, Hauri, Christoph, additional, Hiller, Nicole, additional, Humar, Tadej, additional, Hunziker, Stephan, additional, Ingold, Gerhard, additional, Ischebeck, Rasmus, additional, Janousch, Markus, additional, Juranić, Pavle, additional, Jurcevic, Mario, additional, Kaiser, Maik, additional, Kalantari, Babak, additional, Kalt, Roger, additional, Keil, Boris, additional, Kittel, Christoph, additional, Knopp, Gregor, additional, Koprek, Waldemar, additional, Lemke, Henrik, additional, Lippuner, Thomas, additional, Llorente Sancho, Daniel, additional, Löhl, Florian, additional, Lopez-Cuenca, Carlos, additional, Märki, Fabian, additional, Marcellini, Fabio, additional, Marinkovic, Goran, additional, Martiel, Isabelle, additional, Menzel, Ralf, additional, Mozzanica, Aldo, additional, Nass, Karol, additional, Orlandi, Gian, additional, Ozkan Loch, Cigdem, additional, Panepucci, Ezequiel, additional, Paraliev, Martin, additional, Patterson, Bruce, additional, Pedrini, Bill, additional, Pedrozzi, Marco, additional, Pollet, Patrick, additional, Pradervand, Claude, additional, Prat, Eduard, additional, Radi, Peter, additional, Raguin, Jean-Yves, additional, Redford, Sophie, additional, Rehanek, Jens, additional, Réhault, Julien, additional, Reiche, Sven, additional, Ringele, Matthias, additional, Rittmann, Jochen, additional, Rivkin, Leonid, additional, Romann, Albert, additional, Ruat, Marie, additional, Ruder, Christian, additional, Sala, Leonardo, additional, Schebacher, Lionel, additional, Schilcher, Thomas, additional, Schlott, Volker, additional, Schmidt, Thomas, additional, Schmitt, Bernd, additional, Shi, Xintian, additional, Stadler, Markus, additional, Stingelin, Lukas, additional, Sturzenegger, Werner, additional, Szlachetko, Jakub, additional, Thattil, Dhanya, additional, Treyer, Daniel, additional, Trisorio, Alexandre, additional, Tron, Wolfgang, additional, Vetter, Seraphin, additional, Vicario, Carlo, additional, Voulot, Didier, additional, Wang, Meitian, additional, Zamofing, Thierry, additional, Zellweger, Christof, additional, Zennaro, Riccardo, additional, Zimoch, Elke, additional, Abela, Rafael, additional, Patthey, Luc, additional, and Braun, Hans-Heinrich, additional
- Published
- 2017
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15. Study of a C-Band Standing-Wave Gun for the SwissFEL Injector
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Schaer, Mattia, Bettoni, Simona, Citterio, Alessandro, Craievich, Paolo, Negrazus, Marco, Stingelin, Lukas, and Zennaro, Riccardo
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Physics::Instrumentation and Detectors ,Physics::Accelerator Physics ,03 Particle Sources and Alternative Acceleration Techniques ,T02 Electron Sources ,Accelerator Physics - Abstract
The baseline design of the SwissFEL injector foresees the "PSI Gun 1", a 2.6-cell RF photo-cathode gun operating at S-band frequency, as the electron source. In this paper a new design is presented where a 5.6-cell C-band gun could replace the PSI Gun 1 with no impact on the rest of the injector setup. A conservative maximum gradient of 135 MV/m at the cathode is assumed which drives the electron beam faster into the relativistic regime and therefore allows to tolerate larger charge densities. The presented solution also foresees a coaxial RF coupling from the cathode side in order to place the gun solenoid as near to the photo-cathode as possible, improving the emittance compensation. Astra simulations showed that the transverse beam brightness can be doubled before the first bunch compressor preserving the low transverse emittance value as compared to the current design for the S-band injector configuration of SwissFEL., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany
- Published
- 2014
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16. rf traveling-wave electron gun for photoinjectors
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Schaer, Mattia, primary, Citterio, Alessandro, additional, Craievich, Paolo, additional, Reiche, Sven, additional, Stingelin, Lukas, additional, and Zennaro, Riccardo, additional
- Published
- 2016
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17. Fabrication of the CERN/PSI/ST X-Band accelerating structures
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Dehler, Micha, Atieh, Said, Gudkov, Dmitry, Lebet, Serge, Riddone, Germana, Shi, Jiaru, Citterio, Alessandro, Zennaro, Riccardo, D'Auria, Gerardo, and Serpico, Claudio
- Subjects
Accelerators and Storage Rings - Abstract
In a collaboration between CERN, PSI and Sincrotrone Trieste (ST), a multi- purpose X-band accelerating structure has been designed and fabricated, used for high gradients tests in the CLIC structure testing program and in the FEL projects of PSI and ST. The structure has 72 cells with a phase advance of 5 pi/6 and includes upstream and down-stream wakefield monitors to measure the beam alignment. The SLAC mode launcher design is used to feed it with RF power. Following the CERN fabrication procedures for high-gradient structure, diffusion bonding and brazing in hydrogen atmosphere is used to assemble the cells. After tuning, a vacuum bakeout is required before the feedthroughs for the wake field monitors are welded in as a last step. We describe the experiences gained in finishing the first two structures out of a series of four and present the results from the RF tuning and low level RF tests.
- Published
- 2011
18. Design Concept, Manufacturing and Performance of Test Structures (6 GHz or C-band) for the Linear Accelerator of the SwissFEL X-ray laser system
- Author
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Ellenberger, Urs, primary, Bopp, Markus, additional, Fitze, Hans-Rudolf, additional, Blumer, Heinrich, additional, Paly, Ludwig, additional, Moser, Markus, additional, Kleeb, Max, additional, Raguin, Jean-Yves, additional, Alex, Jürgen, additional, Zennaro, Riccardo, additional, Citterio, Alessandro, additional, and Kleeb, Tom, additional
- Published
- 2013
- Full Text
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