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Author Resta-Lopez, J. doi  openurl
  Title (down) Nonlinear protection of beam delivery systems for multi-TeV linear colliders Type Journal Article
  Year 2013 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 8 Issue Pages P11010 - 19pp  
  Keywords Beam Optics; Beam dynamics; Accelerator Subsystems and Technologies; Accelerator modelling and simulations (multi-particle dynamics; single-particle dynamics)  
  Abstract The post-linac energy collimation system of future e(+)e(-) multi-TeV linear colliders is designed to fulfil an essential function of protection of the Beam Delivery System (BDS) against miss-steered or errant beams likely generated by failure modes in the main linac. For the case of the Compact Linear Collider (CLIC), the energy collimators are required to withstand the impact of a full bunch train in case of failure. This condition makes the design of the energy collimation system especially challenging, if we take into account the need to dispose of an unprecedented transverse beam energy density per beam of the order of GJ/mm(2), when assuming the nominal CLIC beam parameters at 3 TeV centre-of-mass energy, which translates into an extremely high damage potential of uncontrolled beams. This leads to research activities involving new collimator materials and novel collimation techniques. The increase of the transverse spot size at the collimators using nonlinear magnets is a potential solution to guarantee the survival of the collimators. In this paper we present an alternative nonlinear optics based on a multipole magnet pair for energy collimation. In order to preserve an acceptable luminosity performance, we carefully study the general conditions for self-cancellation of optical aberrations between two multipoles. This nonlinear optics scheme is adapted to the requirements of the post-linac energy collimation system for the CLIC BDS, and its performance is investigated by means of beam tracking simulations. Although applied to the CLIC case, this nonlinear protection system could be adapted to other future colliders.  
  Address Univ Valencia, Inst Fis Corpuscular IFIC, Ctr Mixto CSIC, Inst Invest Paterna, Valencia 46071, Spain, Email: resta@ific.uv.es  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000329193500035 Approved no  
  Is ISI yes International Collaboration  
  Call Number IFIC @ pastor @ Serial 1697  
Permanent link to this record
 

 
Author Gonzalez-Iglesias, D.; Gimeno, B.; Esperante, D.; Martinez-Reviriego, P.; Martin-Luna, P.; Fuster-Martinez, N.; Blanch, C.; Martinez, E.; Menendez, A.; Fuster, J.; Grudiev, A. url  doi
openurl 
  Title (down) Non-resonant ultra-fast multipactor regime in dielectric-assist accelerating structures Type Journal Article
  Year 2024 Publication Results in Physics Abbreviated Journal Results Phys.  
  Volume 56 Issue Pages 107245 - 12pp  
  Keywords Multipactor; Dielectric accelerating structures; RF particle accelerators; Plasma discharge  
  Abstract The objective of this work is the evaluation of the risk of suffering a multipactor discharge in an S-band dielectric-assist accelerating (DAA) structure for a compact low-energy linear particle accelerator dedicated to hadrontherapy treatments. A DAA structure consists of ultra-low loss dielectric cylinders and disks with irises which are periodically arranged in a metallic enclosure, with the advantage of having an extremely high quality factor and very high shunt impedance at room temperature, and it is therefore proposed as a potential alternative to conventional disk-loaded copper structures. However, it has been observed that these structures suffer from multipactor discharges. In fact, multipactor is one of the main problems of these devices, as it limits the maximum accelerating gradient. Because of this, the analysis of multipactor risk in the early design steps of DAA cavities is crucial to ensure the correct performance of the device after fabrication. In this paper, we present a comprehensive and detailed study of multipactor in our DAA design through numerical simulations performed with an in-house developed code based on the Monte-Carlo method. The phenomenology of the multipactor (resonant electron trajectories, electron flight time between impacts, etc.) is described in detail for different values of the accelerating gradient. It has been found that in these structures an ultra-fast non-resonant multipactor appears, which is different from the types of multipactor theoretically studied in the scientific literature. In addition, the effect of several low electron emission coatings on the multipactor threshold is investigated. Furthermore, a novel design based on the modification of the DAA cell geometry for multipactor mitigation is introduced, which shows a significant increase in the accelerating gradient handling capabilities of our prototype.  
  Address [Gonzalez-Iglesias, Daniel; Gimeno, Benito; Esperante, Daniel; Martinez-Reviriego, Pablo; Martin-Luna, Pablo; Fuster-Martinez, Nuria; Blanch, Cesar; Martinez, Eduardo; Menendez, Abraham; Fuster, Juan] CSIC UV, Inst Fis Corpuscular IF, c Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: daniel.gonzalez-iglesias@uv.es  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2211-3797 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001133850600001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5866  
Permanent link to this record
 

 
Author n_TOF Collaboration (Cano-Ott, D. et al); Domingo-Pardo, C.; Tain, J.L. doi  openurl
  Title (down) Neutron Capture Measuremetns on Minor Actinides at the n_TOF Facility at CERN: Past, Present and Future Type Journal Article
  Year 2011 Publication Journal of the Korean Physical Society Abbreviated Journal J. Korean Phys. Soc.  
  Volume 59 Issue 2 Pages 1809-1812  
  Keywords n_TOF; Total Absorption Calorimeter; TAC; Neutron capture; Cross section; Nuclear waste; Transmutation; Generation IV; Accelerator driven system; ADS; Nuclear reactor; Nuclear energy; Nuclear data; Barium fluoride; Actinides; Plutonium; Americium; Uranium  
  Abstract The successful development of advanced nuclear systems for sustainable energy production and nuclear waste management depends on high quality nuclear data libraries. Recent sensitivity studies and reports [1-3] have identified the need for substantially improving the accuracy of neutron cross-section data for minor actinides. The n_TOF collaboration has initiated an ambitious experimental program for the measurement of neutron capture cross sections of minor actinides. Two experimental setups have been constructed for this purpose: a Total Absorption Calorimeter (TAC) [4] for measuring neutron capture cross-sections of low-mass and/or radioactive samples and a set of two low neutron sensitivity C(6)D(6) detectors for the less radioactive materials.  
  Address [Cano-Ott, D; Alvarez-Velarde, F; Gonzalez-Romero, E; Guerrero, C; Martinez, T; Mendoza, E; Villamarin, D; Vicente, MC] Ctr Invest Energet Medioambientales & Technol CIE, Madrid, Spain, Email: daniel.cano@ciemat.es  
  Corporate Author Thesis  
  Publisher Korean Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0374-4884 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000294080700085 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 737  
Permanent link to this record
 

 
Author Black, K.M. et al; Zurita, J. url  doi
openurl 
  Title (down) Muon Collider Forum report Type Journal Article
  Year 2024 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 19 Issue 2 Pages T02015 - 95pp  
  Keywords Accelerator Applications; Accelerator Subsystems and Technologies; Instrumentation for particle accelerators and storage rings- high energy (linear accelerators, synchrotrons); Large detector systems for particle and astroparticle physics  
  Abstract A multi-TeV muon collider offers a spectacular opportunity in the direct exploration of the energy frontier. Offering a combination of unprecedented energy collisions in a comparatively clean leptonic environment, a high energy muon collider has the unique potential to provide both precision measurements and the highest energy reach in one machine that cannot be paralleled by any currently available technology. The topic generated a lot of excitement in Snowmass meetings and continues to attract a large number of supporters, including many from the early career community. In light of this very strong interest within the US particle physics community, Snowmass Energy, Theory and Accelerator Frontiers created a cross-frontier Muon Collider Forum in November of 2020. The Forum has been meeting on a monthly basis and organized several topical workshops dedicated to physics, accelerator technology, and detector R&D. Findings of the Forum are summarized in this report.  
  Address [Black, K. M.; Bose, T.; Dasu, S.; Everaerts, P.; Jia, H.; Lomte, S.; Pinna, D.; Venkatasubramanian, N.; Vuosalo, C.] Univ Wisconsin Madison, Madison, WI USA, Email: sergo@fnal.gov  
  Corporate Author Thesis  
  Publisher IOP Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001185309300003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 6048  
Permanent link to this record
 

 
Author Poley, L. et al; Lacasta, C. url  doi
openurl 
  Title (down) Investigations into the impact of locally modified sensor architectures on the detection efficiency of silicon micro-strip sensors Type Journal Article
  Year 2017 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 12 Issue Pages P07006 - 17pp  
  Keywords Si microstrip and pad detectors; Inspection with x-rays; Hybrid detectors; Instrumentation for particle accelerators and storage rings – high energy (linear accelerators, synchrotrons)  
  Abstract The High Luminosity Upgrade of the LHC will require the replacement of the Inner Detector of ATLAS with the Inner Tracker (ITk) in order to cope with higher radiation levels and higher track densities. Prototype silicon strip detector modules are currently developed and their performance is studied in both particle test beams and X-ray beams. In previous test beam measurements of prototype modules, the response of silicon sensors has been studied in detailed scans across individual sensor strips. These scans found instances of sensor strips collecting charge across areas on the sensor deviating from the geometrical width of a sensor strip. The variations have been linked to local features of the sensor architecture. This paper presents results of detailed sensor measurements in both X-ray and particle beams investigating the impact of sensor features (metal pads and p-stops) on the sensor strip response.  
  Address [Poley, L.] DESY, Notkestr, Hamburg, Germany, Email: Anne-Luise.Poley@desy.de  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000406392600006 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3234  
Permanent link to this record
 

 
Author Millar, W.L. et al; Bañon Caballero, D. doi  openurl
  Title (down) High-Power Test of Two Prototype X-Band Accelerating Structures Based on SwissFEL Fabrication Technology Type Journal Article
  Year 2023 Publication IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.  
  Volume 70 Issue 1 Pages 1-19  
  Keywords Radio frequency; Life estimation; Temperature measurement; Wires; Electric breakdown; Brazing; Rendering (computer graphics); Acceleration; breakdown; high gradient; linear accelerator cavity (LINAC); radio frequency (RF); test facilities; vacuum arc; X-band  
  Abstract This article presents the design, construction, and high-power test of two $X$ -band radio frequency (RF) accelerating structures built as part of a collaboration between CERN and the Paul Scherrer Institute (PSI) for the compact linear collider (CLIC) study. The structures are a modified “tuning-free ” variant of an existing CERN design and were assembled using Swiss free electron laser (SwissFEL) production methods. The purpose of the study is two-fold. The first objective is to validate the RF properties and high-power performance of the tuning-free, vacuum brazed PSI technology. The second objective is to study the structures' high-gradient behavior to provide insight into the breakdown and conditioning phenomena as they apply to high-field devices in general. Low-power RF measurements showed that the structure field profiles were close to the design values, and both structures were conditioned to accelerating gradients in excess of 100 MV/m in CERN's high-gradient test facility. Measurements performed during the second structure test suggest that the breakdown rate (BDR) scales strongly with the accelerating gradient, with the best fit being a power law relation with an exponent of 31.14. In both cases, the test results indicate that stable, high-gradient operation is possible with tuning-free, vacuum brazed structures of this kind.  
  Address [Millar, William L. L.; Grudiev, Alexej; Wuensch, Walter; Lasheras, Nuria Catalan; McMonagle, Gerard; Volpi, Matteo; Paszkiewicz, Jan; Edwards, Amelia; Wegner, Rolf; Bursali, Hikmet; Woolley, Benjamin; Magazinik, Anastasiya; Syratchev, Igor; Vnuchenko, Anna; Pitman, Samantha; del Pozo Romano, Veronica; Caballero, David Banon] CERN, CH-1211 Geneva, Switzerland, Email: lee.millar@cern.ch  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9499 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000920658600001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5471  
Permanent link to this record
 

 
Author Scandale, W et al; Lari, L. doi  openurl
  Title (down) Deflection of high energy protons by multiple volume reflections in a modified multi-strip silicon deflector Type Journal Article
  Year 2014 Publication Nuclear Instruments & Methods in Physics Research B Abbreviated Journal Nucl. Instrum. Methods Phys. Res. B  
  Volume 338 Issue Pages 108-111  
  Keywords Accelerator; Beam collimation; Crystal; Channeling; Volume reflection  
  Abstract The effect of multiple volume reflections in one crystal was observed in each of several bent silicon strips for 400 GeV/c protons. This considerably increased the particle deflections. Some particles were also deflected due to channeling in one of the subsequent strips. As a result, the incident beam was strongly spread because of opposite directions of the deflections. A modified multi-strip deflector produced by periodic grooves on the surface of a thick silicon plate was used for these measurements. This technique provides perfect mutual alignment between crystal strips. Such multi-strip deflector may be effective for collider beam halo collimation and a study is planned at the CERN SPS circulating beam.  
  Address [Scandale, W.; Arduini, G.; Butcher, M.; Cerutti, F.; Gilardoni, S.; Lari, L.; Lechner, A.; Losito, R.; Masi, A.; Mereghetti, A.; Metral, E.; Mirarchi, D.; Montesano, S.; Redaelli, S.; Schoofs, P.; Smirnov, G.] CERN, European Org Nucl Res, CH-1211 Geneva 23, Switzerland  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-583x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000343390400016 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1974  
Permanent link to this record
 

 
Author ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Bailey, A.J.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Higon-Rodriguez, E.; Jimenez Pena, J.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Mitsou, V.A.; Pedraza Lopez, S.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Salt, J.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. url  doi
openurl 
  Title (down) Comparison between simulated and observed LHC beam backgrounds in the ATLAS experiment at E-beam=4 TeV Type Journal Article
  Year 2018 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 13 Issue Pages P12006 - 41pp  
  Keywords Accelerator modelling and simulations (multi-particle dynamics; single-particle dynamics); Radiation calculations; Simulation methods and programs  
  Abstract Results of dedicated Monte Carlo simulations of beam-induced background (BIB) in the ATLAS experiment at the Large Hadron Collider (LHC) are presented and compared with data recorded in 2012. During normal physics operation this background arises mainly from scattering of the 4 TeV protons on residual gas in the beam pipe. Methods of reconstructing the BIB signals in the ATLAS detector, developed and implemented in the simulation chain based on the FLUKA Monte Carlo simulation package, are described. The interaction rates are determined from the residual gas pressure distribution in the LHC ring in order to set an absolute scale on the predicted rates of BIB so that they can be compared quantitatively with data. Through these comparisons the origins of the BIB leading to different observables in the ATLAS detectors are analysed. The level of agreement between simulation results and BIB measurements by ATLAS in 2012 demonstrates that a good understanding of the origin of BIB has been reached.  
  Address [Duvnjak, D.; Jackson, P.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000452068100002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3826  
Permanent link to this record
 

 
Author Poley, L. et al; Lacasta, C.; Soldevila, U. url  doi
openurl 
  Title (down) Characterisation of strip silicon detectors for the ATLAS Phase-II Upgrade with a micro-focused X-ray beam Type Journal Article
  Year 2016 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 11 Issue Pages P07023 - 12pp  
  Keywords Inspection with x-rays; Si microstrip and pad detectors; Hybrid detectors; Instrumentation for particle accelerators and storage rings – high energy (linear accelerators, synchrotrons)  
  Abstract The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential through a sizable increase in the luminosity up to 6.10(34) cm(-2) s(-1). A consequence of this increased luminosity is the expected radiation damage at 3000 fb(-1) after ten years of operation, requiring the tracking detectors to withstand fluences to over 1.10(16) 1 MeV n(eq)/cm(2) . In order to cope with the consequent increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk). Two proposed detectors for the ATLAS strip tracker region of the ITk were characterized at the Diamond Light Source with a 3 μm FWHM 15 keV micro focused X-ray beam. The devices under test were a 320 μm thick silicon stereo (Barrel) ATLAS12 strip mini sensor wire bonded to a 130 nm CMOS binary readout chip (ABC130) and a 320 μm thick full size radial (end-cap) strip sensor – utilizing bi-metal readout layers – wire bonded to 250 nm CMOS binary readout chips (ABCN-25). A resolution better than the inter strip pitch of the 74.5 μm strips was achieved for both detectors. The effect of the p-stop diffusion layers between strips was investigated in detail for the wire bond pad regions. Inter strip charge collection measurements indicate that the effective width of the strip on the silicon sensors is determined by p-stop regions between the strips rather than the strip pitch.  
  Address [Poley, L.; Bloch, I.; Diez, S.; Gregor, I. -M.; Lohwasser, K.] DESY, Notkestr, Hamburg, Germany, Email: Anne-Luise.Poley@desy.de  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000387763000014 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2872  
Permanent link to this record
 

 
Author ATLAS Collaboration (Aad, G. et al); Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Fassi, F.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; March, L.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M. url  doi
openurl 
  Title (down) Characterisation and mitigation of beam-induced backgrounds observed in the ATLAS detector during the 2011 proton-proton run Type Journal Article
  Year 2013 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 8 Issue Pages P07004 - 72pp  
  Keywords Pattern recognition, cluster finding, calibration and fitting methods; Performance of High Energy Physics Detectors; Accelerator modelling and simulations (multi-particle dynamics; single-particle dynamics); Analysis and statistical methods  
  Abstract This paper presents a summary of beam-induced backgrounds observed in the ATLAS detector and discusses methods to tag and remove background contaminated events in data. Trigger-rate based monitoring of beam-related backgrounds is presented. The correlations of backgrounds with machine conditions, such as residual pressure in the beam-pipe, are discussed. Results from dedicated beam-background simulations are shown, and their qualitative agreement with data is evaluated. Data taken during the passage of unpaired, i.e. non-colliding, proton bunches is used to obtain background-enriched data samples. These are used to identify characteristic features of beam-induced backgrounds, which then are exploited to develop dedicated background tagging tools. These tools, based on observables in the Pixel detector, the muon spectrometer and the calorimeters, are described in detail and their efficiencies are evaluated. Finally an example of an application of these techniques to a monojet analysis is given, which demonstrates the importance of such event cleaning techniques for some new physics searches.  
  Address [Jackson, P.; Soni, N.] Univ Adelaide, Sch Chem & Phys, Adelaide, SA, Australia  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000322572900015 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1557  
Permanent link to this record
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