John Adams Institute
for Accelerator Science

The need to reduce the size and cost of particle accelerators has triggered novel ideas. Using a plasma as a transformer of laser energy, capable of creating accelerating fields 3 to 4 orders of magnitude above those currently available with conventional technology, is a new concept with the potential to revolutionise accelerators. Though ultra-high accelerating gradients and electron beams in the 1GeV energy range have been demonstrated, a lot of efforts are still necessary before building a laser plasma accelerator. In particular, the control of the properties of the accelerating structure, determining the stability and reproducibility of the process, is a crucial issue. After introducing the basics of laser plasma accelerators, and illustrating the current state of the art, I will present recent results and a prospective option for future linear accelerators.

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The STFC is going to build at Harwell and Daresbury Innovation Campuses a centre dedicated to detector systems technology. Its function will be to bring academic and industrial collaborators together with STFC's world-class detector capabilities and knowledge base. It will develop and commercialise sensors and integrated detector solutions for both Research Council and industrially applicable markets such as security and biomedical imaging.

The presentation will introduce the innovation campus vision and STFC's gateway centres. The technology capabilities of the Detector Centre will then be expanded in more detail. In addition how it will operate will be described as well as its plans for further academic and commercial engagement. Example projects and routes for engagement with Oxford will be discussed.

The Detector Centre is a 30m investment from the RCUK Large Facility Capital Fund and will be split between Harwell and Daresbury. Construction is expected to start in the next 12 months and the Centre formally launched for project activity from April of this year.

ISIS at the STFC Rutherford Appleton Laboratory in Oxfordshire, UK, provides unique sources of both pulsed neutrons and muons for exploring the properties of matter by measuring the locations of atoms and the forces between them.

We will explore how the ISIS accelerator systems, targets, beamlines and instruments operate and look at some of the extraordinary science done at the facility.

Unique combination of in-vacuum undulator and high gradient C-band accelerator made possible to construct the accelerator based X-ray FEL (1 Angstrom) within 700 m length site available at SPring-8 Japan, which is much shorter than the 3.4 km long XFEL  (1 Angstrom) based on super conducting accelerator technology. The low emittance electron source uses single crystal CeB6 thermionic cathode, which has been developed at RIKEN/SPring-8 during 2001-2005, and it has been routinely used in SCSS test accelerator (UVU FEL) since 2006. The 8 GeV X-ray FEL construction started in 2006, this is fourth year out of 5 year project. Talk will provide current status of the construction and also some information of the application.

I will describe recent work on wake‐assisted self guiding of ultra‐short laser pulses over tens of Rayleigh lengths in a plasma and on the measurement of the threshold power for self trapping in this regime.
To get trapping and acceleration at lower laser powers, ionization induced injection into the wakes is explored. Some initial results at 100TW in cm scale plasmas will be presented.

The feasibility study for a possible future linear collider named CLIC (Compact Linear Collider) will be presented. CLIC is based on the Two Beams concept composed of a Main Beam Linac accelerating leptons and a Drive Beam Linac providing the RF power for the acceleration. CLIC is based on normal conducting accelerating structures (100 MV/m and 12 GHz) and therefore it is today the only linear collider able to reach the multi-TeV range with the present CLIC design at 3 TeV centre of mass. In a first stage, electrons and positrons would collide at 500 GeV, as for the ILC (International Linear Collider). The strong synergy between the ILC and CLIC studies will be illustrated. Today, several key parameters remain to be demonstrated for the CLIC technology. An R&D program is ongoing at CERN with the present CLIC Tests Facility (CTF3).
In this seminar, the status and the results already obtained in CTF3 and the perspective for the future will be presented.

Radiofrequency (RF) photoguns, presently the brightest pulsed electron sources, were originally developed as injectors for (X-ray) Free Electron Lasers. In recent years exciting small-scale applications have emerged as well, such as pulsed radiolysis, femtosecond electron diffraction, and generation of intense THz pulses.

At Eindhoven University of Technology RF photoguns are being developed which are characterized by full cylindrical symmetry and 100-fs photoemission in the bunch blow-out regime. A new technological feature of our 2nd generation 1.5 cell RF photogun is clamping of the different parts instead of brazing, preventing deformation during the brazing process. Our approach results in picosecond electron bunches of a few MeV with peak currents in excess of 100 A and a normalized emittance better than 1 mm·mrad, corresponding to state-of-the-art brightness.

We have used these bunches to generate strong, single-cycle free-space THz pulses by means of the coherent transition radiation (CTR) process. In addition we have shown that the CTR process can be used to generate intense single-cycle THz pulses coupled to the surface of a metal wire, so-called surface plasmon polaritons (SPPs). SPPs propagating along a metal wire can be focused to a spot much smaller than the wavelength by simply tapering the wire into a sharp tip. In this way highly localized fields of unprecedented strengths can be realized at THz frequencies, opening up an entirely new experimental regime.

The Linac Coherent Light Source at SLAC, the world's highest energy and peak intensity X-ray laser has recently become operational. The system makes use of the the last kilometer of the 40 year old SLAC LINAC with a new high brightness injector and undulator system to produce fewfemtosecond long pulses of coherent Xrays with energies from 800eV to 9KeV and peak powers above 10 GW.

Laser-plasma accelerators can accelerate electrons to relativistic energies over distances three orders of magnitude smaller than required by their conventional radio-frequency counterparts. By focusing beams from TW- to PW-class lasers into a gas target, electrons can get trapped and accelerated in longitudinal fields of several hundred GV/m. Recent breakthroughs have led to stable, quasi-monoenergetic electron beams in the GeV-scale from few-centimeter accelerator lengths. Owing to their unprecedented features, such as intrinsically ultrashort pulse durations and expected low emittances, these electron beams are perfectly suited for driving a next generation of X-ray light sources. Both, unique coherent free-electron lasers (FELs) and spontaneous undulator light sources with femtosecond to attosecond pulse durations could be realized on a laboratory-sized scale. The wide-spread operation of such X-ray sources holds promise for an enormous impact in many fields of science, technology and medicine. In this talk, I will discuss laser-wakefield acceleration, present design considerations for a table-top FEL as well as first experimental breakthroughs towards this end, manifesting itself in the first laser-driven undulator source in the soft-X-ray range.

The SuperB international project aims at the construction of an asymmetric (4x7 GeV), very high luminosity, B-Factory near Rome (Italy). The luminosity goal of 10³⁶ cm-2s-1 can be reached with a new collision scheme, with large Piwinski angle and the use of "crab waist" sextupoles, which has been successfully tested at the DAΦNE Φ-Factory at LNF-Frascati (Italy) in 2008-2009. This regime will allow for operation with relatively low beam currents, comparable to those of the PEP-II and KEKB B-Factories. The beams, with extremely low emittances, will be strongly focused at the Interaction Point, and a sophisticated Interaction Region design has been designed. In the High Energy Ring two spin rotators will permit bringing longitudinally polarized electrons into collision. The lattice has been designed with a very low intrinsic emittance in order to have a compact layout, about 2 Km length. A Conceptual Design Report was published in March 2007, and beam dynamics and collective effects R&D studies are in progress in order to publish a Technical Design Report by the end of 2010.

PHIL is a new linac test facility under construction at LAL. The size of this machine is modest with respect to other LAL contribution to CTF3 or PITZ facilities, but this accelerator is not only dedicated to test photo-injectors technologies but also to the training of students and engineers. In addition, PHIL, will be opened to physic experiments which need a low energy and well definite electron beam as detector calibrations.

The project of an e+ e- high luminosity ( L peak> 10**36 cm-2 s-1) collider is presented. Physics motivation and the physics program in the era of LHC and complementary with the LHC program is discussed in the context of a global flavour approach to new physics. It includes some special features of the machine as: beam polarization mainly for tau physics, possibility to run around open charm threshold. The machine design is also presented, based on the positive results of the tests in DAPHNE machine in Frascati of the "Crab Waist" ideas. Concepts and a basic design of the detector are shown.

High power proton accelerators (HPPA's) with beam powers in the megawatt range have many possible applications, including drivers for spallation neutron sources, neutrino factories, accelerator driven sub-critical reactors and nuclear waste transmuters. These applications typically propose beam powers of 5 MW or more, compared to the highest beam power achieved from a pulsed proton accelerator in routine operation of 0.2 MW at the ISIS spallation neutron source at RAL. Achieving such high powers is not straightforward: significant reductions in beam losses -- below 1 W/m -- are required, coupled with the necessary increase in beam current and quality.

The Front End Test Stand (FETS) is an accelerator test assembly currently under development at RAL, in collaboration with Imperial, Warwick and the Basque University, Bilbao. The aim of FETS is to demonstrate the production of a high quality 60 mA, 2 ms, 50 Hz, chopped H- beam at 3 MeV. This requires the development of a high current H- source, an accelerator section based on RadioFrequency Quadrupoles (RFQ's), a fast beam chopper and corresponding beam transport. Also under development are a series of novel beam diagnostics. This talk will focus on the accelerator background behind FETS and where the current technical challenges lie.

The Large Hadron Collider (LHC) at the European Laboratory for Particle Physics (CERN) is on the verge of restarting later this year following first beam on 10 September 2008 and the incident which brought the machine to a standstill on 19 September last year. By colliding unparalleled high-energy and high-intensity beams, the LHC will launch a new era of research in particle physics and will open up previously unexplored territory at the TeV scale in great detail, allowing the experiments to probe deeper inside matter and providing an understanding of processes that occurred very early in the history of the Universe. This presentation reviews the basic ingredients of the LHC accelerator, the status of preparations for the restart, and discusses typical accelerator parameters and associated performance levels. Dedicated runs with heavy ions and protons are discussed, and a typical LHC accelerator operation schedule is shown. This talk will also provide a short review of the new accelerator projects at CERN.

Hadron therapy has entered a new age, with a steadily growing number of facilities and high "consumer" interest. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. The presentation surveys the current requirements and directions in accelerator technology for hadron therapy.

Beam diagnostics and instrumentation are an essential part of any kind of accelerator. There is a large variety of parameters to be measured for observation of particle beams with the precision required to tune, operate and improve the machine. One of the crucial parameters is transverse particle beam emittance because it is directly related to the brilliance of a synchrotron light source or the luminosity of a particle beam collider. Therefore a precise online control of the beam profile is highly desirable from which the corresponding emittance can be calculated. In addition observation of the particle beam shape's time--like evolution allows to study effects as for example injection mismatch and dynamical beta beating which are important for smooth--running accelerator operation. Due to its non--destructive nature synchrotron radiation is a versatile tool for beam profile measurements and is used in nearly every accelerator. While in principle synchrotron radiation from insertion devices or bending magnets can be utilized, in reality most accelerators use bending magnet radiation based profile monitoring because of space limitations. There exist a number of different techniques in order to overcome limitations due to resolution broadening effects which can result in theoretical resolutions down to the sub--micron level. In this talk an overview over the methods presently applied in most accelerators will be given.

The detailed numerical investigation of the highly nonlinear physics involved in the interaction of a laser-pulse with a plasma and/or an externally injected beam requires suitable simulation tools which are able to retain the basic features of the process without increasing too much the computational needs. ALaDyn (Acceleration by LAser and DYNamics of charged particles) is a relativistic fully parallelized Particle In Cell (PIC) code developed at the University of Bologna in the framework of the INFN-CNR project PLASMONX (PLASma acceleration and MONochromatic X-rays production). In ALaDyn the algorithms for the electromagnetic fields evolution are based on (compact) high order finite differences schemes ensuring spectral-like accuracy.

This feature together with the possibility to adopt a nonuniform computational grid, a hierarchical particles sampling and high order time integration schemes allows us to increase the accuracy in the results compared to standard PIC codes keeping fixed (or even reducing) memory requirements and simulation length compared to standard 2-nd order accurate PIC codes. In the first part of this talk we will present the main features and the performances of the code together with a set of validation tests obtained comparing the results with well-established analytical/numerical results. The second part of the talk is devoted to the applications of the code. We will focus first on the generation of a low emittance, high charge and low momentum spread electron bunch from laser-plasma interaction in the laser wakefield acceleration regime (LWFA) in view of achieving beam brightness of interest for the All-Optical Free Electron Laser (AO-FEL). Then we will consider the application of ALaDyn to the PLASMONX project. In particular we will deal with the first "pilot" experiment concerning the acceleration of self-injected electrons.

In the last part of the talk we will focus on some preliminary simulations concerning the ion acceleration from laser-target interaction in the Radiation Pressure Acceleration (RPA) regime. This study has been done within the framework of the PROMETHEUS project whose goal is the production of high quality ion bunches for medical applications.

ALICE (Accelerator and Lasers In Combined Experiments) is an energy recovery linac based R&D facility. It is about to enter its final commissioning period that will set this machine fully operational. This will open up a great number of research opportunities not only within the remit of accelerator R&D but also in various applications of the ALICE light sources. The presentation will give a short summary of the ALICE accelerator and light sources (IR FEL, CBS based x-ray source, femtosecond TW and tuneable lasers, THz), outline commissioning and research objectives for the year 2008-09 and provide an overview of further planned and potential developments and research projects on ALICE.

The seminar will introduce the physics opportunities offered by the CLIC multi-TeV e+e- collider. It will then describe the requirements for a CLIC experiment concept at the 3 TeV baseline centre-of-mass energy, taking into account the beam properties and expected background conditions. The CLIC detector requirements will be compared with the ILC case, showing that the design and R&D work currently being carried out for ILC is applicable to CLIC in many areas. The seminar will then bring forward areas where R&D in detector development and engineering titles will be needed specifically for CLIC.

Lepton flavor violation of charged leptons has attracted much interest from theorists and experimentalists since it would have potentials to get important hints for new physics beyond the Standard Model. In particular, a process of muon to electron conversion in a muonic atom is considered to be one of the best to search for. In this talk, a new proposal to search for muon to electron conversion with sensitivity of less than 10^{-16} at J-PARC will be presented together with the development of a highly intense muon source based on FFAGs.

Today, nuclear energy seems to be approaching a second pivotal point. There are strong indications of increased interest in new technologies for future nuclear energy, which are stimulated by enhanced concerns on the sustainability of nuclear power. Current key issues in nuclear fuel cycle threatening sustainability of nuclear energy are availability of resources, waste disposal, non-proliferation and the possibility of severe accidents. These key issues were reviewed from the viewpoint of nuclear material management (e.g. thorium vs uranium), the technology using these materials (e.g. accelerator-driven sub-critical systems), and the reprocessing schemes.

FERMI@Elettra will be a free-electron laser user facility based on a seeded high-gain harmonic generation (HGHG) free-electron laser. A room temperature linac coupled to a photocathode rf gun will provide the high-energy, high-brightness electron beam to the undulator system. The seed signal will then be up shifted in frequency via the HGHG process and amplified to gigawatt levels. The FEL operates over the range from 100 nm to 10 nm, but provisions have been made to possibly push this down to 3 nm at the fundamental and even further if one uses the naturally occurring nonlinear harmonics.

In this seminar we will present the FERMI@Elettra project primarily from a beam physics point of view. Following a brief description of the motivating science we will then proceed to describe the overall beam physics plan as well as our methods of implementation and overall project timeline.

After a brief description of the world-wide context on Linear Colliders and of the CLIC scheme to extend Linear Colliders into the Multi-TeV colliding beam energy range, the main challenges and the very promising results already achieved will be presented. The Test Facility (CTF3) presently under construction at CERN by a broad collaboration (with a fruitful UK participation) to address the main key issues and demonstrate the feasibility of the CLIC technology before 2010 will be described. The presentation will then focus on the CLIC -ILC collaboration recently set-up to address the common issues on titles with strong synergies between the two studies.

The LHC is an accelerator with unprecedented complexity where the energy stored in the magnets and in the beams exceeds that of other accelerators by one-to-two orders of magnitude. To ensure a safe and efficient machine start-up, and in order to mitigate any technical problems, a phase of so-called ''hardware commissioning'' has been introduced during which a thorough commissioning of technical systems without beam is undertaken. This paper discusses the experience with this approach, presents results from the commissioning of the first LHC sectors and provides an outlook for future activities.

The strategy for a staged commissioning period with beam, that is to follow the ''hardware commissioning'' phase, is also presented. Typical accelerator parameters and associated performance levels are given for each stage. Dedicated runs with heavy ions and protons are discussed, and a typical LHC accelerator operation schedule is shown.

All experiments will have installed initial detectors and will be ready for commissioning with beam at the start of LHC operation in 2008. The physics programme is expected to be rich even at the projected initial luminosities. This talk also presents the requirements and expectations of the experiments for the accelerator start-up with beam and early collisions, the heavy-ion runs and the special proton runs, initial conditions that may be used subsequently to set priorities in order to exploit optimally the first LHC beams for physics.