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| MOPFI074 | Ultracold and High Brightness Electron Source for Next Generation Particle Accelerators | 452 |
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| The ultra-cold plasma-based electron source has recently been proposed as an alternative to the conventional photoemitters or thermionic electron guns, which are widely used in today’s particle accelerators. The advantages of the ultra-cold plasma-based electron source lie in the fact that the electron beam extracted from the cold plasma (from ionization of cold atoms) has very low electron temperature, e.g. down to 10 K, and has the potential for producing high brightness and ultra-short electron bunches. All these features are crucial for the next generation particle accelerators, e.g. free electron lasers, plasma-based accelerators and the future linear colliders. In this paper, we will introduce our proposed facility on cold electron source based at Photon Science Institute (PSI) in the University of Manchester. | ||
| MOPWO028 | Recent Developments and Future Plans for SixTrack | 948 |
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Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404. SixTrack is a symplectic 6D tracking code routinely used to simulate single particle trajectories in high energy circular machines like the LHC and RHIC. The paper presents the developments recently implemented and those foreseen for extending the physics models: exact Hamiltonian, different ions and charge states, RF multipoles, non-linear fringe fields, Taylor maps, e-lenses, ion scattering. Moreover new functionalities are also added like variable number of tracked particles, time dependent strengths, GPU computations with a refactoring of the core structure. The developments will benefit studies on the LHC and SPS, for collimation efficiency, ion operations, failure scenarios and HL-LHC design. |
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| MOPWO034 | Energy Deposition Studies for the Upgrade of the LHC Injection Lines | 963 |
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| The LHC Injectors Upgrade (LIU) Project aims at upgrading the systems in the LHC injection chain, to reliably deliver the beams required by the High-Luminosity LHC (HL-LHC). Given the challenging beam intensities and emittances, a review of the existing beam-intercepting devices is on-going, in order to assess heat loads and consequent thermo-mechanical stresses. Moreover, the exposure of downstream elements to induced shower radiation is assessed. The study is intended to spot possible issues and contribute to the definition of viable design and layout solutions. | ||
| TUPEA058 | The Conceptual Design of CLARA, A Novel FEL Test Facility for Ultrashort Pulse Generation | 1265 |
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| The conceptual design of CLARA, a novel FEL test facility focussed on the generation of ultrashort photon pulses with extreme levels of stability and synchronisation is described. The ultimate aim of CLARA is to experimentally demonstrate, for the first time, that sub-coherence length pulse generation with FELs is viable. The results will translate directly to existing and future X-Ray FELs, enabling them to generate attosecond pulses, thereby extending the science capabilities of these intense light sources. This paper will describe the design of CLARA, pointing out the flexible features that will be incorporated to allow multiple novel FEL schemes to be proven. | ||
| TUPFI023 | Optics Design and Lattice Optimisation for the HL-LHC | 1385 |
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Funding: The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Cap. Spec. Progr, Grant Agreement 284404. The luminosity upgrade project of the LHC collider at CERN is based on a strong focusing scheme to reach smallest beam sizes at the collision points. Depending on the available magnet technology (Nb3Sn or NbTi) a number of beam optics has been developed to define the specifications for the new super conducting quadrupoles. In the context of the optics matching new issues have been addressed and new concepts have been used: Quadrupole strength flexibility and chromatic corrections have been studied, as well as the influence of quadrupole fringe fields. The lattice has been optimised including the needs of the foreseen crab cavities and the transition between injection and low β optics had to guarantee smooth gradient changes over a wide range of β* values. Tolerances on misalignments and power converter ripple have been re-evaluated. Finally the combination of the quadrupole strengths in the high luminosity matching sections with those in the neighboring sectors is explained, a key concept of the ATS to reach smallest β* values. This paper presents the results obtained within the HiLumi collaboration Task 2.2 and summarises the main parameters of the project. |
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| TUPWO054 | Recent Results from the EMMA Experiment | 1988 |
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| EMMA (Electron Model for Many Applications) is a prototype non-scaling electron FFAG hosted at Daresbury Laboratory. After a recent demonstration of acceleration in the serpentine channel, the injected EMMA beam was further studied. This entails the continuation of the exploration of the large transverse and longitudinal acceptance and the effects of slower integer tune crossing on the betatron amplitude. A single closed orbit correction that is effective at multiple momenta (and hence over a significant range in tune space) was implemented. A comparison with a detailed model based on measured field maps, and the experimental mapping of the machine by relating the initial and final phase space coordinates was also done. These recent results together with more practical improvements such as injection orbit matching with real-time monitoring of the coordinates in the transverse phase space will be reported in this paper. | ||
| WEPEA058 | LSS Layout Optimizations for Low-beta Optics for the HL-LHC | 2639 |
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Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404 The High Luminosity LHC (HL-LHC) project aims to upgrade the existing LHC to a peak luminosity of the order 1035cm-2s−1, while retaining as much of the nominal layout and hardware as possible. The current baseline for this upgrade is the use of the Achromatic Telescopic Squeeze (ATS) concept, which allows mini-Beta squeeze in IRs 1 and 5 (ATLAS and CMS respectively) far below that possible with nominal optics. However it is useful to both explore the parameter space of the ATS scheme while also attempting to push the boundaries of the nominal layout. This paper presents a study into maximising optical flexibility of the nominal LHC Long Straight Sections (LSSs) around IPs 1 and 5. This involves replacing, moving or adding magnets within the LSS to investigate feasibility of exploiting a more conventional optical scheme than the ATS scheme. In particular the option of replacing single LSS quadrupoles with doublets is explored. The study also looks at making similar changes to the LSS while also implementing the ATS scheme, to further explore the ATS parameter space with the benefit of experience gained into flexibility of a modified nominal LHC optical scheme. |
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| WEPEA059 | Study of the Impact of Fringe Fields of the Large Aperture Triplets on the Linear Optics of the HL-LHC | 2642 |
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Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404 High-luminosity hadron colliders such as the High Luminosity LHC (HL-LHC) project place demanding requirements on existing and new magnet technology. The very low β* achieved by the Achromatic Telescopic Squeeze (ATS) optics scheme* for the HL-LHC in particular, requires large apertures in the high gradient Nb3Sn final focusing inner triplet triplet. Such magnets have extended fringe fields which perturb the linear and non-linear optics. This paper presents results of studies into the liner optics of the LHC using a range of fringe field models, including measurements of fringe fields from prototype magnets, and presents calculations of the beta-beating in the machine. Furthermore a similar study is presented on the nominal LHC optics, which uses final focus quadrupoles of higher gradient but significantly smaller aperture. * S. Fartoukh, ‘’An Achromatic Telescopic Squeezing (ATS) Scheme for LHC Upgrade’’, in proceedings of IPAC11, p. 2088. |
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| WEPEA064 | SixTrack-Fluka Active Coupling for the Upgrade of the SPS Scrapers | 2657 |
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| The LHC Injectors Upgrade (LIU) Project aims at upgrading the systems in the LHC injection chain, to reliably deliver the beams required by the High-Luminosity LHC (HL-LHC). Essential for the clean injection into the LHC, the SPS scrapers are one of the important systems under revision. In order to take into account of the effect of betatron and longitudinal beam dynamics on energy deposition patterns, and nuclear and Coulomb scattering in the absorbing medium onto loss patterns, the SixTrack and Fluka codes have been coupled, profiting from the best of the refined physical models they respectively embed. The coupling envisages an active exchange of tracked particles between the two codes at each turn, and an on-line aperture check in SixTrack, in order to estimate the local cleaning inefficiency of the system. Knob-like, time-dependent strengths have been implemented in SixTrack, since the designed scraper system foresees the use of a magnetic bump. The study is intended to assess the robustness of the proposed scraper as well as its effectiveness with respect to the desired performance. | ||
| WEPEA074 | Optimisation of the Beam Line for COMET Phase-I | 2681 |
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| The COMET experiment will search for very rare muon processes that will give us an insight into particle physics beyond the Standard Model. COMET requires an intense beam of muons with a momentum less than 70 MeV/c. This is achieved using an 8 GeV proton beam; a heavy metal target to primarily produce pions; a solenoid capture system; and a curved solenoid to perform charge and momentum selection. It was recently proposed to build COMET is two phases with physics measurements being made in both phases. This requires re-optimising the beam line for a shorter curved solenoid. This will affect the pion and muon yield; the momentum distributions at the detector; and the collimator scheme required. This paper will present the beam line design for COMET Phase-I, which aims to maximise the yield for low momentum muons suppressing sources of backgrounds in the beam. | ||
| WEPEA075 | Large Emittance Beam Measurements for COMET Phase-I | 2684 |
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| The COMET experiment will search for very rare muon processes that will give us an insight into particle physics beyond the Standard Model. COMET requires an intense beam of muons with a momentum less than 70 MeV/c. This is achieved using an 8 GeV proton beam; a heavy metal target to primarily produce pions; a solenoid capture system; and a curved solenoid to perform charge and momentum selection. Understanding the pion production yield and transport properties of the beam line is an important part of the experiment. The beam line is a continuous solenoid channel, so it is only possible to place a beam diagnostic device at the end of the beam line. Building COMET in two phases provides the opportunity to investigate the pion production yield and to measure the transport properties of the beam line in Phase-I. This paper will demonstrate how this will be done using the experimental set up for COMET Phase-I. | ||
| WEPEA076 | Comparison of Taylor Maps with Radio Frequency Multipoles in a Thin Lens 6D Tracking Code | 2687 |
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Funding: HiLumi LHC Design Study is part of the High Luminosity LHC project and is part funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404. SixTrack is a general purpose 6D thin lens tracking code used for dynamic aperture studies. In the high luminosity LHC upgrade it is proposed that crab cavities are used to enhance the luminosity. In this study, for the current proposed optics, we consider the use of RF multipoles and Taylor maps as methods to simulate crab cavity elements in the lattice. |
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| WEPEA077 | Applying the 'Simple Accelerator Modelling in Matlab' (SAMM) Code to High Luminosity LHC Upgrade | 2690 |
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| The "Simple Accelerator Modelling in Matlab" (SAMM) code is a set of Matlab routines for modelling beam dynamics in high energy particle accelerators. It includes a set of CUDA codes that can be run on a Graphics Processor Unit. These can be called from SAMM and can speed up tracking simulations by 100 times. To make use of this potential for the computationally intensive LHC upgrade simulations, we have developed additional Matlab and CUDA routines to simulate the full set of elements that are present in the Large Hadron Collider. We present the results of applying these codes to dynamic aperture calculations. These results are benchmarked against PTC and MADX. | ||