64 research outputs found
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: [
Studies of Cs3Sb cathodes for the CLIC drive beam photo injector option
No full textWithin the CLIC (Compact Linear Collider) project, feasibility studies of a photo injector option for the drive beam as an alternative to its baseline design using a thermionic electron gun are on-going. This R&D program covers both the laser and the photocathode side. Whereas the available laser pulse energy in ultra-violet (UV) is currently limited by the optical defects in the 4thharmonics frequency conversion crystal induced by the0.14 ms long pulse trains, recent measurements of Cs3Sbphotocathodes sensitive to green light showed their potential to overcome this limitation. Moreover, using visible laser beams leads to better stability of produced electron bunches and one can take advantages of the availability of higher quality optics. The studied Cs3Sbphotocathodes have been produced in the CERN photo emission laboratory using the co-deposition technique and tested in a DC gun set-up. The analysis of data acquired during the cathode production process will be presented in this paper, as well as the results of lifetime measurements in the DC gu
X-ray Photoemission Spectroscopy Studies of Cesium Antimonide Photocathodes for Photoinjector Applications
No full textWithin the CLIC (Compact Linear Collider) project, feasibility studies of a photoinjector option for the drive beam as an alternative to its baseline design using a thermionic electron gun (Geschonke et al. [1] ) are on-going. This R&D; program covers both the laser and the photocathode side. Cesium antimonide cathodes were produced at CERN by co-deposition onto copper substrates and characterized by photoemission and by XPS (X-ray Photoemission Spectroscopy) analysis. A systematic study on newly produced and used photocathodes was conducted in order to correlate the surface composition to the photoemissive properties
Surface Characterization at CERN of Photocathodes for Photoinjector Applications
No full textR&D; on photocathodes takes place at CERN within the CLIC (Compact Linear Collider) project. Photocathodes are produced as thin films on Oxygen Free copper substrate using a co-deposition technique, and characterized in a dedicated laboratory with a DC photo-electron gun. A new UHV carrier vessel compatible with CERN’s XPS (X-ray Photoelectron Spectroscopy) analysis equipment has been commissioned and is used to transport photocathodes from the production laboratory to perform a systematic study of different compounds used as photoemissive materials. In this paper photocathodes used in a RF photoinjector will be characterized and the correlation of their surface properties with their performance will be investigated
Production of Mass-Separated Erbium-169 Towards the First Preclinical in vitro Investigations
No full textThe β−-particle-emitting erbium-169 is a potential radionuclide toward therapy of metastasized cancer diseases. It can be produced in nuclear research reactors, irradiating isotopically-enriched 168Er2O3. This path, however, is not suitable for receptor-targeted radionuclide therapy, where high specific molar activities are required. In this study, an electromagnetic isotope separation technique was applied after neutron irradiation to boost the specific activity by separating 169Er from 168Er targets. The separation efficiency increased up to 0.5% using resonant laser ionization. A subsequent chemical purification process was developed as well as activity standardization of the radionuclidically pure 169Er. The quality of the 169Er product permitted radiolabeling and pre-clinical studies. A preliminary in vitro experiment was accomplished, using a 169Er-PSMA-617, to show the potential of 169Er to reduce tumor cell viability. © Copyright © 2021 Talip, Borgna, Müller, Ulrich, Duchemin, Ramos, Stora, Köster, Nedjadi, Gadelshin, Fedosseev, Juget, Bailat, Fankhauser, Wilkins, Lambert, Marsh, Fedorov, Chevallay, Fernier, Schibli and van der Meulen.The authors thank CERN ISOLDE and RILIS teams for the laser operation (Maxim D. Seliverstov, Katerina Chrysalidis), radiation protection and logistic teams of PSI (Tobias Schneider) and CERN (Alexandre Dorsival, Matthieu Deschamps and Elodie Aubert, Philippe Bertreix, Nicolas Riggaz, Nabil Menaa, Aurore Boscher, Jeremie Comte, Benjamin Juif); the LARISSA workgroup of Mainz University for the laser preparation and erbium laser ionization scheme development (Prof. Dr. Klaus Wendt and Dr. Dominik Studer). The authors are grateful to Fan Sozzi-Guo, Muhamet Djelili, Alexander V?gele and Walter Hirzel (PSI) and Bernard Cr?pieux, Giacomo Lunghi, Francesco Riccardi, Miranda Van Stenis, Thomas Schneider (CERN) for technical support. Funding. ZT and NM received funding from the Swiss National Science Foundation (SNF Grant Number: 200021_188495). CM obtained funding for this project from the Swiss Cancer Research (KFS-4678-02-2019-R). FB received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sk?odowska-Curie Grant Agreement No 701647
Study of the Performance of Cs2Te Cathodes in the PHIN RF Photoinjector using Long Pulse Trains
No full textThe drive beam of CLIC requires unusually high peak and average currents which is challenging for the electron source. As an alternative to the thermionic electron gun foreseen in the baseline design, a photoinjector option is under study at CERN using the PHIN photoinjector, which was designed for a bunch charge of 2.3 nC and 1200 ns train length. During operation with nominal train length in 2014, a large pressure increase in the vacuum system, attributed to a heating of the Faraday cup, caused a degradation of the photocathode. To overcome this problem a vacuum window has been installed to separate the Faraday cup from the rest of the vacuum system. In addition the train length has been further increased to 1600 ns to advance the beam parameters towards CLIC requirements. In this paper recent improved photocathode lifetime measurements carried out under these new conditions will be presented and compared with earlier measurements. Furthermore, the utilized Cs2Te cathode has been analyzed with X-ray Photoelectron Spectroscopy (XPS) before and after its usage in PHIN to get a better understanding of photocathode surface deterioration effects, which will also be discussed
Production and investigation of heavy neutron rich nuclei
No full textA project devoted to the production and study of neutron rich heavy nuclei (GALS - project) is being realized at Flerov Laboratory for Nuclear Reactions (FLNR) - JINR. GALS is planned to exploit available beams from the U-400M cyclotron in low energy multi-nucleon transfer reactions to study exotic neutron rich nuclei located in the "north-east" region of nuclear map. Products from 4.5 to 9 MeV/nucleon heavy-ion collisions, such as 136Xe on 208Pb, are to be captured in a gas cell and selectively laser-ionized in a sextupole (quadrupole) ion guide extraction system
Efficient Production of High Specific Activity Thulium-167 at Paul Scherrer Institute and CERN-MEDICIS
No full textThulium-167 is a promising radionuclide for nuclear medicine applications with potential use for both diagnosis and therapy (“theragnostics”) in disseminated tumor cells and small metastases, due to suitable gamma-line as well as conversion/Auger electron energies. However, adequate delivery methods are yet to be developed and accompanying radiobiological effects to be investigated, demanding the availability of 167Tm in appropriate activities and quality. We report herein on the production of radionuclidically pure 167Tm from proton-irradiated natural erbium oxide targets at a cyclotron and subsequent ion beam mass separation at the CERN-MEDICIS facility, with a particular focus on the process efficiency. Development of the mass separation process with studies on stable 169Tm yielded 65 and 60% for pure and erbium-excess samples. An enhancement factor of thulium ion beam over that of erbium of up to several 104 was shown by utilizing laser resonance ionization and exploiting differences in their vapor pressures. Three 167Tm samples produced at the IP2 irradiation station, receiving 22.8 MeV protons from Injector II at Paul Scherrer Institute (PSI), were mass separated with collected radionuclide efficiencies between 11 and 20%. Ion beam sputtering from the collection foils was identified as a limiting factor. In-situ gamma-measurements showed that up to 45% separation efficiency could be fully collected if these limits are overcome. Comparative analyses show possible neighboring mass suppression factors of more than 1,000, and overall 167Tm/Er purity increase in the same range. Both the actual achieved collection and separation efficiencies present the highest values for the mass separation of external radionuclide sources at MEDICIS to date.sponsorship: This research received funding from the Swiss National Science Foundation (SNF Grant Number: 200021_188495), the Research Foundation Flanders FWO (Belgium) under contracts FWO SBO Tb-IRMA-V No. S005019N and WO IRI ISOLDE No. I002619N, and the European Union's Horizon 2020 research and innovation programme under grant agreement No. 101008571 (PRISMAP - The European medical radionuclides programme). (Swiss National Science Foundation (SNF Grant)|200021_188495, Research Foundation Flanders FWO (Belgium)|S005019N, Research Foundation Flanders FWO (Belgium)|I002619N, European Union's Horizon 2020 research and innovation programme|101008571, Swiss National Science Foundation (SNF)|200021_188495)status: Publishe
GALS – setup for production and study of heavy neutron rich nuclei
No full textThe present limits of the upper part of the nuclear map are very close to stability while the unexplored area of heavy neutron-rich nuclides along the neutron closed shell N = 126 below 208Pb is extremely important for nuclear astrophysics investigations and, in particular, for the understanding of the r-process of astrophysical nucleosynthesis. This area of the nuclear map can be reached neither in fusion–fission reactions nor in fragmentation processes widely used nowadays for the production of exotic nuclei. A new way was recently proposed for the production of these nuclei via low-energy multi-nucleon transfer reactions. The estimated yields of neutron-rich nuclei are found to be significantly high in such reactions and several tens of new nuclides can be produced, for example, in the near-barrier collision of 136Xe with 208Pb. A new setup is proposed to produce and study heavy neutron-rich nuclei located along the neutron closed shell N=126
- …
