Author: Welsch, C.P.
Paper Title Page
MOEPPB010 Measurement of Satellite Bunches at the LHC 97
 
  • A. Jeff, M. Andersen, A. Boccardi, S. Bozyigit, E. Bravin, T. Lefèvre, A. Rabiller, F. Roncarolo
    CERN, Geneva, Switzerland
  • A.S. Fisher
    SLAC, Menlo Park, California, USA
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Funding: Adam Jeff is a DITANET fellow, supported by the EU's Marie Curie actions contract PITN-GA-2008-215080.
The RF gymnastics involved in the delivery of proton and lead ion bunches to the LHC can result in satellite bunches of varying intensity occupying the nominally empty RF buckets. Quantification of these satellites is crucial for bunch-by-bunch luminosity normalization as well as for machine protection. We present an overview of the longitudinal density monitor (LDM) which is the principal instrument for the measurement of satellite bunches in the LHC. The LDM uses single photon counting of synchrotron light. The very high energies reached in the LHC, combined with a dedicated undulator for diagnostics, allow synchrotron light measurements to be made with both protons and heavy ions. The arrival times of photons are collected over a few million turns, with the resulting histogram corrected for the effects of the detector’s deadtime and afterpulsing in order to reconstruct the longitudinal profile of the entire LHC ring. The LDM has achieved a dynamic range in excess of 105 and a time resolution of 90 ps. Example results are presented and the measurements are benchmarked against satellite distributions based on collision data from the LHC experiments.
 
 
MOPPC060 Investigations into Beam Life Time in Low Energy Storage Rings 271
 
  • A.I. Papash, A.V. Smirnov
    MPI-K, Heidelberg, Germany
  • A.I. Papash
    JINR, Dubna, Moscow Region, Russia
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Funding: Work supported by the Helmholtz Association of National Research Centers and GSI under contract VH-NG-328.
In low energy storage rings, beam life time critically depends on the residual gas pressure, scattering effects caused by in-ring experiments and the available machine acceptance. A comprehensive simulation study into these effects has been realized with a focus on the TSR storage ring in Heidelberg and the electrostatic rings ELISA, the AD recycler and the ultra-low energy storage ring (USR). This was done by using the computer code BETACOOL in combination with the OPERA-3D and MAD-X programs. In this contribution, the results from these studies are presented and compared to available experimental data. Based on these simulations, criteria for stable ring operation are then presented.
 
 
MOPPC061 An Antiproton Recycler for Atom-Antiproton Collision Experiments 274
 
  • M.R.F. Siggel-King, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • O. Karamyshev, A.I. Papash
    MPI-K, Heidelberg, Germany
  • M.R.F. Siggel-King
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the Helmholtz Association and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080 and STFC.
Collision experiments with low energy antiprotons and different gas jet targets on the level of differential cross sections would be very desirable to use to investigate the details of this fundamental process. At present, such experiments are, however, not feasible, since the only source of antiprotons in the world, the AD at CERN, cannot provide beams of the required energy and quality. A small electrostatic ring has been designed and developed by the QUASAR Group. Serving at the same time as a prototype for the future ultra-low energy storage ring (USR), to be integrated at the facility for low-energy antiproton and ion research (FLAIR), this small accelerator is unique due to its combination of size, electrostatic nature, and energy of the circulating particles. In this contribution, the design of the ring is described in detail and possible operation scenarios in the ASACUSA beam line and behind the ELENA ring are compared with each other.
 
 
MOPPD001 Accelerator R&D in the QUASAR Group 364
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the Helmholtz Association and GSI under contract VH-NG-328, the EU under contracts PITN-GA-2008-215080, PITN-GA-2011-289191, PITN-GA-2011-289485 and STFC.
The QUASAR Group was founded in 2007 with an initial focus on the development and experimental exploitation of a novel electrostatic ultra-low energy storage ring (USR), part of the future facility for low-energy antiproton and ion research (FLAIR). The group's research activities have grown considerably over the past four years and now include also the development of beam diagnostic tools for accelerators and light sources, investigations into superconducting linear accelerators and medical applications, and, most recently, a broad R&D program into laser applications at accelerators. In this contribution, an overview of the QUASAR Group’s research achievements to date is given.
 
 
MOPPD002 Ultra-low Energy Storage Ring at FLAIR 367
 
  • C.P. Welsch, D. Newton, M.R.F. Siggel-King
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • O.E. Gorda, O. Karamyshev, G.A. Karamysheva, M. Panniello, A.I. Papash, A.V. Smirnov
    MPI-K, Heidelberg, Germany
  • J. Harasimowicz, M. Putignano, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: The support of the HGF and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080, the Max Planck Institute for Nuclear Physics and the STFC Grant ST/G008248/1 is acknowledged.
The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters will be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 106 were carried out. Here, we present the USR design with an emphasis on the expected beam parameters available to the experiments at FLAIR.
 
 
MOPPD003 DITANET - An International Network in Beam Diagnostics 370
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the European Union under contract PITN-GA-2008-215080.
DITANET is the largest-ever EU funded research and training network in beam diagnostics. It brings together universities, research centers and industry partners to jointly develop diagnostics methods for a wide range of existing or future particle accelerators. This is achieved through a cohesive approach that allows for the exploitation of synergies, whilst promoting knowledge exchange between partners. In addition to its broad research program, the network organizes a large number of international schools and topical workshops for the beam instrumentation and particle accelerator communities. The project comes to an end in May 2012. This contribution presents some of the network's recent research outcomes and training activities.
 
 
MOPPD004 oPAC - Optimizing Accelerators through International Collaboration 373
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the European Union under contract PITN-GA-2011-289485.
The optimization of the performance of any particle accelerator critically depends on an in-depth understanding of the beam dynamics in the machine and the availability of simulation tools to study and continuously improve all accelerator components. It also requires a complete set of beam diagnostics methods to monitor all important machine and beam parameters with high precision and a powerful control and data acquisition system. Within the oPAC project all these aspects will be closely linked with the aim to optimize the performance of present and future accelerators that lie at the heart of many research infrastructures. The project brings together 22 institutions from around the world. With a project budget of 6 M€, it is one of the largest research and training networks ever funded by the EC. This contribution gives an overview of the network's broad research program and summarizes the training events that will be organized by the consortium within the next 4 years.
 
 
MOPPR048 Beam Instrumentation for the HIE-ISOLDE Linac at CERN 891
 
  • E. Bravin, A.G. Sosa, D. Voulot, F.J.C. Wenander, F. Zocca
    CERN, Geneva, Switzerland
  • M.A. Fraser
    UMAN, Manchester, United Kingdom
  • J.H. Galipienzo
    AVS, Eibar, Gipuzkoa, Spain
  • M. Pasini
    Instituut voor Kern- en Stralingsfysica, K. U. Leuven, Leuven, Belgium
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  In the framework of the High Intensity and Energy (HIE)-ISOLDE project at CERN, a beam instrumentation R&D program is on-going for the superconducting upgrade of the REX-ISOLDE heavy-ion post-accelerator. An overview of the foreseen beam diagnostics system is presented, focusing on the challenging specifications required by the HIE-ISOLDE linac. Due to the low beam intensities, the diagnostic instrumentation will be based on high-sensitivity intercepting devices. The project includes intensity and transverse profile monitors to be implemented in the very narrow longitudinal space that is available for beam diagnostics in the regions between the superconducting cryomodules. A longitudinal profile monitor is foreseen downstream of the linac to measure the beam energy and arrival time distributions and to allow for a fast phase-tuning of the superconducting cavities. A custom-made emittance meter will provide transverse emittance measurements based on a phase space sampling technique. The design status of the different instruments will be presented as well as the results of some experimental tests.  
 
WEPPC033 RF and Surface Properties of Bulk Niobium and Niobium Film Samples 2278
 
  • T. Junginger, W. Weingarten
    CERN, Geneva, Switzerland
  • R. Seviour
    University of Huddersfield, Huddersfield, United Kingdom
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Funding: Work supported by the German Doctoral Students program of the Federal Ministry of Education and Research (BMBF)
The surface resistance Rs of superconducting cavities can be obtained from the unloaded quality factor Q0. Since RS varies strongly over the cavity surface its value must be interpreted as averaged over the whole cavity surface. A more convenient way to investigate the surface resistance of superconducting materials is therefore to examine small samples, because they can be manufactured cheaply, duplicated easily and used for further surface analyses. At CERN a compact Quadrupole Resonator has been developed for the RF characterization of superconducting samples at different frequencies. In this contribution, results from measurements on bulk niobium and niobium film on copper samples are presented. Different models accounting for the field depended surface resistance are being confronted by the experimental results. The RF results are being correlated to surface analyses measurements carried out on the same samples.
 
 
WEPPC034 LA³NET - An International Network on Laser Applications at Accelerators 2281
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This project is funded by the European Union under contract PITN-GA-2011-289191.
Lasers have become increasingly important for the successful operation and continuous optimization of particle accelerators: Laser-based particle sources are well suited for delivering the highest quality ion and electron beams, laser acceleration has demonstrated unprecedented accelerating gradients and might be an alternative for conventional particle accelerators in the future, and without laser-based beam diagnostics it would not be possible to unravel the characteristics of many complex particle beams. The LA³NET project will bring together research centers, universities, and industry partners to jointly train 17 early stage researchers. In addition, the consortium will also organize a number of international training events, such as schools, topical workshops and conferences. This contribution gives examples from the network's broad research program and summarizes planned training events.
 
 
MOPPD001 Accelerator R&D in the QUASAR Group 364
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the Helmholtz Association and GSI under contract VH-NG-328, the EU under contracts PITN-GA-2008-215080, PITN-GA-2011-289191, PITN-GA-2011-289485 and STFC.
The QUASAR Group was founded in 2007 with an initial focus on the development and experimental exploitation of a novel electrostatic ultra-low energy storage ring (USR), part of the future facility for low-energy antiproton and ion research (FLAIR). The group's research activities have grown considerably over the past four years and now include also the development of beam diagnostic tools for accelerators and light sources, investigations into superconducting linear accelerators and medical applications, and, most recently, a broad R&D program into laser applications at accelerators. In this contribution, an overview of the QUASAR Group’s research achievements to date is given.
 
 
MOPPD003 DITANET - An International Network in Beam Diagnostics 370
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the European Union under contract PITN-GA-2008-215080.
DITANET is the largest-ever EU funded research and training network in beam diagnostics. It brings together universities, research centers and industry partners to jointly develop diagnostics methods for a wide range of existing or future particle accelerators. This is achieved through a cohesive approach that allows for the exploitation of synergies, whilst promoting knowledge exchange between partners. In addition to its broad research program, the network organizes a large number of international schools and topical workshops for the beam instrumentation and particle accelerator communities. The project comes to an end in May 2012. This contribution presents some of the network's recent research outcomes and training activities.
 
 
MOPPD004 oPAC - Optimizing Accelerators through International Collaboration 373
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: Work supported by the European Union under contract PITN-GA-2011-289485.
The optimization of the performance of any particle accelerator critically depends on an in-depth understanding of the beam dynamics in the machine and the availability of simulation tools to study and continuously improve all accelerator components. It also requires a complete set of beam diagnostics methods to monitor all important machine and beam parameters with high precision and a powerful control and data acquisition system. Within the oPAC project all these aspects will be closely linked with the aim to optimize the performance of present and future accelerators that lie at the heart of many research infrastructures. The project brings together 22 institutions from around the world. With a project budget of 6 M€, it is one of the largest research and training networks ever funded by the EC. This contribution gives an overview of the network's broad research program and summarizes the training events that will be organized by the consortium within the next 4 years.
 
 
MOPPD002 Ultra-low Energy Storage Ring at FLAIR 367
 
  • C.P. Welsch, D. Newton, M.R.F. Siggel-King
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • O.E. Gorda, O. Karamyshev, G.A. Karamysheva, M. Panniello, A.I. Papash, A.V. Smirnov
    MPI-K, Heidelberg, Germany
  • J. Harasimowicz, M. Putignano, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: The support of the HGF and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080, the Max Planck Institute for Nuclear Physics and the STFC Grant ST/G008248/1 is acknowledged.
The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters will be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 106 were carried out. Here, we present the USR design with an emphasis on the expected beam parameters available to the experiments at FLAIR.
 
 
WEPPC034 LA³NET - An International Network on Laser Applications at Accelerators 2281
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This project is funded by the European Union under contract PITN-GA-2011-289191.
Lasers have become increasingly important for the successful operation and continuous optimization of particle accelerators: Laser-based particle sources are well suited for delivering the highest quality ion and electron beams, laser acceleration has demonstrated unprecedented accelerating gradients and might be an alternative for conventional particle accelerators in the future, and without laser-based beam diagnostics it would not be possible to unravel the characteristics of many complex particle beams. The LA³NET project will bring together research centers, universities, and industry partners to jointly train 17 early stage researchers. In addition, the consortium will also organize a number of international training events, such as schools, topical workshops and conferences. This contribution gives examples from the network's broad research program and summarizes planned training events.