RF Beam control system for the Brookhaven relativistic heavy ion collider, RHIC

International Nuclear Information System (INIS)

Brennan, J.M.; Campbell, A.; Delong, J.; Hayes, T.; Onillon, E.; Rose, J.; Vetter, K.

1998-01-01

The Relativistic Heavy Ion Collider, RHIC, is two counter-rotating rings with six interaction points. The RF Beam Control system for each ring will control two 28 MHz cavities for acceleration, and five 197 MHz cavities for preserving the 5 ns bunch length during 10 hour beam stores. Digital technology is used extensively in: Direct Digital Synthesis of rf signals and Digital Signal Processing for, the realization of state-variable feedback loops, real-time calculation of rf frequency, and bunch-by-bunch phase measurement of the 120 bunches. DSP technology enables programming the parameters of the feedback loops in order to obtain closed-loop dynamics that are independent of synchrotron frequency

The Brookhaven ATF low-emittance beam line

International Nuclear Information System (INIS)

Wang, X.J.; Kirk, H.G.

1991-01-01

One component of the experimental program at the Brookhaven Accelerator Test Facility (ATF) consists of a class of experiments which will study the acceleration of electrons through micron-size structures which are exposed in coincidence to a 100 GW CO 2 laser beam. These experiments require the development and control of an electron beam with geometric emittances on the order of 10 -10 m-rad and intensities on the order of 10 6 electrons. In this paper, the authors describe the strategies for producing such beams and the effects of higher-order aberrations. Particle tracking results are presented for the final-focus system

Excitation of accelerating plasma waves by counter-propagating laser beams

International Nuclear Information System (INIS)

Shvets, Gennady; Fisch, Nathaniel J.; Pukhov, Alexander

2002-01-01

The conventional approach to exciting high phase velocity waves in plasmas is to employ a laser pulse moving in the direction of the desired particle acceleration. Photon downshifting then causes momentum transfer to the plasma and wave excitation. Novel approaches to plasma wake excitation, colliding-beam accelerator (CBA), which involve photon exchange between the long and short counter-propagating laser beams, are described. Depending on the frequency detuning Δω between beams and duration τ L of the short pulse, there are two approaches to CBA. First approach assumes (τ L ≅2/ω p ). Photons exchanged between the beams deposit their recoil momentum in the plasma driving the plasma wake. Frequency detuning between the beams determines the direction of the photon exchange, thereby controlling the phase of the plasma wake. This phase control can be used for reversing the slippage of the accelerated particles with respect to the wake. A variation on the same theme, super-beatwave accelerator, is also described. In the second approach, a short pulse with τ L >>ω p -1 detuned by Δω∼2ω p from the counter-propagating beam is employed. While parametric excitation of plasma waves by the electromagnetic beatwave at 2ω p of two co-propagating lasers was first predicted by Rosenbluth and Liu [M. N. Rosenbluth and C. S. Liu, Phys. Rev. Lett. 29, 701 (1972)], it is demonstrated that the two excitation beams can be counter-propagating. The advantages of using this geometry (higher instability growth rate, insensitivity to plasma inhomogeneity) are explained, and supporting numerical simulations presented

The Brookhaven ATF low-emittance beam line

International Nuclear Information System (INIS)

Wang, X.J.

1991-01-01

One component of the experimental program at the Brookhaven Accelerator Test Facility (ATF) consists of a class of experiments which will study the acceleration of electrons through micron-size structures which are exposed in coincidence to a 100 GW CO 2 laser beam. These experiments require the development and control of an electron beam with geometric emittances on the order of 10 -10 m-rad and intensities on the order of 10 6 electrons. In this paper, we describe the strategies for producing such beams and the effects of high-order aberrations. Particle tracking results are presented for the final-focus system. 9 refs., 6 figs., 2 tabs

Advanced R ampersand D for electron and photon beams at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Kirk, H.G.

1989-08-01

The Brookhaven Accelerator Test Facility consists of a 50-MeV linear accelerator and a laser system capable of generating short (a few picoseconds) laser pulses at both UV (266 nm) and infrared (10 μm) wavelengths. With these systems in place, the ATF has unique capabilities for the study of fundamental interactions between charged-particle beams and intense electromagnetic radiation. The principal research goals of the Accelerator Test Facility (ATF) axe the following. Laser Acceleration Program: We wig study the principles and techniques of particle acceleration at ultra-high frequencies (up to 30 THz) and with very high acceleration gradients (up to 1 GV/m). Production of Coherent Radiation: We wish to develop the next generation of photon sources with features like (a) short pulses (picoseconds or less), (b) coherence, and (c) high peak power. All of these attributes can be provided by free-electron lasers. High-brightness sources: A common denominator for the above programs is the need for electron beams with very small transverse and longitudinal emittances. We will devote a substantial amount of our resources to the production and understanding of electron beams that have these attributes. We will build advanced electron sources such as switched-power devices and rf guns with photocathodes. Important applications of this line of research include the development of high-luminosity linear colliders and free-electron lasers in the XUV regime

Relativistic-Klystron two-beam accelerator as a power source for future linear colliders

International Nuclear Information System (INIS)

Lidia, S. M.; Anderson, D. E.; Eylon, S.; Henestroza, E.; Vanecek, D. L.; Yu, S. S.; Houck, T. L.; Westenskow, G. A.

1999-01-01

The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, 1-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 300 pi-mm-mr. The prototype accelerator will be used to study, physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented

Beam-beam observations in the Relativistic Heavy Ion Collider

Energy Technology Data Exchange (ETDEWEB)

Luo, Y. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Laboratory (BNL), Upton, NY (United States); White, S. [Brookhaven National Laboratory (BNL), Upton, NY (United States)

2015-06-24

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has been operating since 2000. Over the past decade, thanks to the continuously increased bunch intensity and reduced β*s at the interaction points, the maximum peak luminosity in the polarized proton operation has been increased by more than two orders of magnitude. In this article, we first present the beam-beam observations in the previous RHIC polarized proton runs. Then we analyze the mechanisms for the beam loss and emittance growth in the presence of beam-beam interaction. The operational challenges and limitations imposed by beam-beam interaction and their remedies are also presented. In the end, we briefly introduce head-on beam-beam compensation with electron lenses in RHIC.

BROOKHAVEN: Japanese collaboration

International Nuclear Information System (INIS)

Thieberger, Peter

1995-01-01

Full text: The Japanese RIKEN Laboratory is contributing $20 million to help construct the RHIC Relativistic Heavy Ion Collider now being built at Brookhaven and due to be completed in 1999. In return, RIKEN will participate in research at RHIC. RHIC is being built to collide beams of heavy ions at energies of about 100 GeV per nucleon to explore hot and dense states of nuclear matter, with the ultimate aim of finding the quark-gluon plasma, the medium which existed in the fiery aftermath of the Big Bang before subsequently 'freezing' into nucleons. However another long-time Brookhaven speciality is handling beams of polarized (spin-oriented) protons in the 30 GeV AGS Alternating Gradient Synchrotron, which will act as the injector for RHIC. With the involvement of RIKEN, the RHIC programme now expands to cover polarized protons. Half of the RIKEN support will be used to build and install the special hardware needed to handle the polarized beams in RHIC. This includes 'Siberian Snakes' to negotiate depolarizing resonances which would otherwise mar beam acceleration (September 1994, page 27). The remaining RIKEN funding will go towards additional equipment for the PHENIX detector (May 1992, page 10) to enable it to cover spin physics. This equipment includes a second muon arm, with a magnet and tracking chamber. A multidisciplinary laboratory, RIKEN - Rikagaku Kenkyusho, or the Institute of Physical and Chemical Research - near Tokyo is currently the scene of construction of an 8 GeV synchrotron X-ray source

The Colliding Beams Sequencer

International Nuclear Information System (INIS)

Johnson, D.E.; Johnson, R.P.

1989-01-01

The Colliding Beam Sequencer (CBS) is a computer program used to operate the pbar-p Collider by synchronizing the applications programs and simulating the activities of the accelerator operators during filling and storage. The Sequencer acts as a meta-program, running otherwise stand alone applications programs, to do the set-up, beam transfers, acceleration, low beta turn on, and diagnostics for the transfers and storage. The Sequencer and its operational performance will be described along with its special features which include a periodic scheduler and command logger. 14 refs., 3 figs

The Brookhaven Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Chou, T.S.; Fernow, R.C.

1988-01-01

The Brookhaven Accelerator Test Facility (ATF) will consist of a 50--100 MeV/c electron linac and a 100 GW CO 2 laser system. A high brightness RF-gun operating at 2856 MHz is to be used as the injector into the linac. The RF-gun contains a Nd:Yag-laser-driven photocathode capable of producing a stream of six ps electron pulses separated by 12.5 ns. The maximum charge in a micropulse will be one nano-Coulomb. The CO 2 laser pulse length will be a few picoseconds and will be synchronized with the electron pulse. The first experimental beam is expected in Fall 89. The design electron beam parameters are given and possible initial experiments are discussed. 9 refs., 1 fig., 3 tabs

The generation and acceleration of low emittance flat beams for future linear colliders

Energy Technology Data Exchange (ETDEWEB)

Raubenheimer, Tor O. [Stanford Univ., CA (United States)

1991-11-01

Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of γϵ_x = 3x10^-6 m-rad and γϵ_y = 3x10^-8 m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate ``fundamental`` limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.

The generation and acceleration of low emittance flat beams for future linear colliders

Energy Technology Data Exchange (ETDEWEB)

Raubenheimer, T.O.

1991-11-01

Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of {gamma}{epsilon}{sub x} = 3{times}10{sup {minus}6} m-rad and {gamma}{epsilon}{sub y} = 3{times}10{sup {minus}8} m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate fundamental'' limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.

The generation and acceleration of low emittance flat beams for future linear colliders

International Nuclear Information System (INIS)

Raubenheimer, T.O.

1991-11-01

Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of γε x = 3x10 -6 m-rad and γε y = 3x10 -8 m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate ''fundamental'' limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future

ISABELLE: a 400 x 400 GeV proton--proton colliding beam facility

International Nuclear Information System (INIS)

1978-01-01

A conceptual design report is presented for the construction of an Intersecting Storage Accelerator, ISABELLE, to be located at Brookhaven National Laboratory. At this major research facility beams of protons with energies up to 400 GeV will be collided in six experimental areas. At each area particle physicists will install detector apparatus to study the interaction and reaction products for such very high energy collisions. The proposal results from several years of study and development work on such a facility. Topics discussed include: (1) introduction and summary of the proposal; (2) physics at ISABELLE (including physics objectives and typical experiments and detectors); description of ISABELLE (overview; magnetic ring structure and lattice characteristics; performance; beam transfer, stacking, and acceleration; magnet system; refrigeration system; vacuum system; power supplies, instrumentation, and control system; physical plant and experimental halls; and operation and safety); and (3) cost estimate and schedule

ISABELLE: a 400 x 400 GeV proton--proton colliding beam facility

Energy Technology Data Exchange (ETDEWEB)

None

1978-01-01

A conceptual design report is presented for the construction of an Intersecting Storage Accelerator, ISABELLE, to be located at Brookhaven National Laboratory. At this major research facility beams of protons with energies up to 400 GeV will be collided in six experimental areas. At each area particle physicists will install detector apparatus to study the interaction and reaction products for such very high energy collisions. The proposal results from several years of study and development work on such a facility. Topics discussed include: (1) introduction and summary of the proposal; (2) physics at ISABELLE (including physics objectives and typical experiments and detectors); description of ISABELLE (overview; magnetic ring structure and lattice characteristics; performance; beam transfer, stacking, and acceleration; magnet system; refrigeration system; vacuum system; power supplies, instrumentation, and control system; physical plant and experimental halls; and operation and safety); and (3) cost estimate and schedule.

The Brookhaven Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Chou, T.S.; Fernow, R.C.; Fischer, J.; Gallardo, J.; Kirk, H.G.; Koul, R.; Palmer, R.B.; Pellegrini, C.; Sheehan, J.; Srinivasan-Rao, T.; Ulc, S.; Woodle, M.; Bigio, I.; Kurnit, N.; McDonald, K.T.

1989-01-01

The Brookhaven Accelerator Test Facility ATF will consist of a 50-100 MeV/c electron linac and a 100 GW CO 2 laser system. A high brightness RF-gun operating at 2,856 MHz is to be used as the injector into the linac. The RF-gun contains a Nd:Yag-laser-driven photocathode capable of producing a stream of six ps electron pulses separated by 12.5 ns. The maximum charge in a micropulse will be one nano-Coulomb. The CO 2 laser pulse length will be a few picoseconds and will be synchronized with the electron pulse. The first experimental beam is expected in Fall 89. The design electron beam parameters are given and possible initial experiments are discussed. 9 refs., 1 fig., 3 tabs

Collective accelerator for electron colliders

Energy Technology Data Exchange (ETDEWEB)

Briggs, R.J.

1985-05-13

A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch.

Collective accelerator for electron colliders

International Nuclear Information System (INIS)

Briggs, R.J.

1985-01-01

A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch

NOVOSIBIRSK/STANFORD: colliding linac beams

International Nuclear Information System (INIS)

Anon.

1979-01-01

Plans to use colliding beams from linear accelerators are being considered at Novosibirsk and Stanford. The VLEPP scheme proposed for Novosibirsk and the Stanford single pass collider scheme are described. (W.D.L.).

Recombinant Science: The Birth of the Relativistic Heavy Ion Collider (431st Brookhaven Lecture)

International Nuclear Information System (INIS)

Crease, Robert P.

2007-01-01

As part of the celebration of Brookhaven Lab's 60th anniversary, Robert P. Crease, the Chair of the Philosophy Department at Stony Brook University and BNL's historian, will present the second of two talks on the Lab's history. In 'Recombinant Science: The Birth of the Relativistic Heavy Ion Collider,' Dr. Crease will focus on the creation of the world's most powerful colliding accelerator for nuclear physics. Known as RHIC, the collider, as Dr. Crease will recount, was formally proposed in 1984, received initial construction funding from the U.S. Department of Energy in 1991, and started operating in 2000. In 2005, the discovery at RHIC of the world's most perfect liquid, a state of matter that last existed just moments after the Big Bang, was announced, and, since then, this perfect liquid of quarks and gluons has been the subject of intense study.

Muon Collider Progress: Accelerators

Energy Technology Data Exchange (ETDEWEB)

Zisman, Michael S.

2011-09-10

A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

Status of the Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Lee, S.Y.

1990-01-01

Accelerator Physics issues, such as the dynamical aperture, the beam lifetime and the current--intensity limitation are carefully studied for the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The single layer superconducting magnets, of 8 cm coil inner diameter, satisfying the beam stability requirements have also been successfully tested. The proposal has generated wide spread interest in the particle and nuclear physics. 1 ref., 4 figs., 3 tabs

RHIC and quark matter: proposal for a relativistic heavy ion collider at Brookhaven National Laboratory

International Nuclear Information System (INIS)

1984-08-01

This document describes the Brookhaven National Laboratory Proposal for the construction of a Relativistic Heavy Ion Collider (RHIC). The construction of this facility represents the natural continuation of the laboratory's role as a center for nuclear and high-energy physics research and extends and uses the existing AGS, Tandem Van de Graaff and CBA facilities at BNL in a very cost effective manner. The Administration and Congress have approved a project which will provide a link between the Tandem Van de Graaf and the AGS. Completion of this project in 1986 will provide fixed target capabilities at the AGS for heavy ions of about 14 GeV/amu with masses up to approx. 30 (sulfur). The addition of an AGS booster would extend the mass range to the heaviest ions (A approx. 200, e.g., gold); its construction could start in 1986 and be completed in three years. These two new AGS experimental facilities can be combined with the proposed Relativistic Heavy Ion Collider to extend the energy range to 100 x 100 GeV/amu for the heaviest ions. BNL proposes to start construction of RHIC in FY 86 with completion in FY 90 at a total cost of 134 M$

Online beam energy measurement of Beijing electron positron collider II linear accelerator

Science.gov (United States)

Wang, S.; Iqbal, M.; Liu, R.; Chi, Y.

2016-02-01

This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

Future e+e- linear colliders and beam-beam effects

International Nuclear Information System (INIS)

Wilson, P.B.

1986-05-01

Numerous concepts, ranging from conventional to highly exotic, hae been proposed for the acceleration of electrons and positrons to very high energies. For any such concept to be viable, it must be possible to produce from it a set of consistent parameters for one of these ''benchmark'' machines. Attention is directed to the choice of parameters for a collider in the 300 GeV energy range, operating at a gradient on the order of 200 MV/m, using X-band power sources to drive a conventional disk-loaded accelerating structure. These rf power sources, while not completely conventional represent a reasonable extrapolation from present technology. The choice of linac parameters is strongly coupled to various beam-beam effects which take place when the electron and positron bunches collide. We summarize these beam-beam effects, and then return to the rf design of a 650 GeV center-of-mass collider. 14 refs

BROOKHAVEN: Booster commissioned

Energy Technology Data Exchange (ETDEWEB)

Bleser, Ed

1992-03-15

The construction and first commissioning phase of the Booster synchrotron to inject into Brookhaven's veteran Alternating Gradient Synchrotron (AGS) were completed last year. Scheduled to come into operation this year, the new Booster will extend the research capabilities AGS, and with its ability to accelerate partially stripped heavy ions will play an essential role in the chain of accelerators serving the Relativistic Heavy Ion Collider (RHIC)

Brookhaven National Laboratory electron beam test stand

International Nuclear Information System (INIS)

Pikin, A.; Alessi, J.; Beebe, E.; Kponou, A.; Prelec, K.; Snydstrup, L.

1998-01-01

The main purpose of the electron beam test stand (EBTS) project at the Brookhaven National Laboratory is to build a versatile device to develop technologies that are relevant for a high intensity electron beam ion source (EBIS) and to study the physics of ion confinement in a trap. The EBTS will have all the main attributes of EBIS: a 1-m-long, 5 T superconducting solenoid, electron gun, drift tube structure, electron collector, vacuum system, ion injection system, appropriate control, and instrumentation. Therefore it can be considered a short prototype of an EBIS for a relativistic heavy ion collider. The drift tube structure will be mounted in a vacuum tube inside a open-quotes warmclose quotes bore of a superconducting solenoid, it will be at room temperature, and its design will employ ultrahigh vacuum technology to reach the 10 -10 Torr level. The first gun to be tested will be a 10 A electron gun with high emission density and magnetic compression of the electron beam. copyright 1998 American Institute of Physics

Effects of rf breakdown on the beam in the Compact Linear Collider prototype accelerator structure

Directory of Open Access Journals (Sweden)

A. Palaia

2013-08-01

Full Text Available Understanding the effects of rf breakdown in high-gradient accelerator structures on the accelerated beam is an extremely relevant aspect in the development of the Compact Linear Collider (CLIC and is one of the main issues addressed at the Two-beam Test Stand at the CLIC Test Facility 3 at CERN. During a rf breakdown high currents are generated causing parasitic magnetic fields that interact with the accelerated beam affecting its orbit. The beam energy is also affected because the power is partly reflected and partly absorbed thus reducing the available energy to accelerate the beam. We discuss here measurements of such effects observed on an electron beam accelerated in a CLIC prototype structure. Measurements of the trajectory of bunch trains on a nanosecond time scale showed fast changes in correspondence of breakdown that we compare with measurements of the relative beam spots on a scintillating screen. We identify different breakdown scenarios for which we offer an explanation based also on measurements of the power at the input and output ports of the accelerator structure. Finally we present the distribution of the magnitude of the observed changes in the beam position and we discuss its correlation with rf power and breakdown location in the accelerator structure.

The rise of colliding beams

International Nuclear Information System (INIS)

Richter, B.

1992-06-01

It is a particular pleasure for me to have this opportunity to review for you the rise of colliding beams as the standard technology for high-energy-physics accelerators. My own career in science has been intimately tied up in the transition from the old fixed-target technique to colliding-beam work. I have led a kind of double life both as a machine builder and as an experimenter, taking part in building and using the first of the colliding-beam machines, the Princeton-Stanford Electron-Electron Collider, and building the most recent advance in the technology, the Stanford Linear Collider. The beginning was in 1958, and in the 34 years since there has been a succession of both electron and proton colliders that have increased the available center-of-mass energy for hard collisions by more than a factor of 1000. For the historians here, I regret to say that very little of this story can be found in the conventional literature. Standard operating procedure for the accelerator physics community has been publication in conference proceedings, which can be obtained with some difficulty, but even more of the critical papers are in internal laboratory reports that were circulated informally and that may not even have been preserved. In this presentation I shall review what happened based on my personal experiences and what literature is available. I can speak from considerable experience on the electron colliders, for that is the topic in which I was most intimately involved. On proton colliders my perspective is more than of an observer than of a participant, but I have dug into the literature and have been close to many of the participants

Brookhaven National Laboratory's Accelerator Test Facility: research highlights and plans

Science.gov (United States)

Pogorelsky, I. V.; Ben-Zvi, I.

2014-08-01

The Accelerator Test Facility (ATF) at Brookhaven National Laboratory has served as a user facility for accelerator science for over a quarter of a century. In fulfilling this mission, the ATF offers the unique combination of a high-brightness 80 MeV electron beam that is synchronized to a 1 TW picosecond CO2 laser. We unveil herein our plan to considerably expand the ATF's floor space with an upgrade of the electron beam's energy to 300 MeV and the CO2 laser's peak power to 100 TW. This upgrade will propel the ATF even further to the forefront of research on advanced accelerators and radiation sources, supporting the most innovative ideas in this field. We discuss emerging opportunities for scientific breakthroughs, including the following: plasma wakefield acceleration studies in research directions already active at the ATF; laser wakefield acceleration (LWFA), where the longer laser wavelengths are expected to engender a proportional increase in the beam's charge while our linac will assure, for the first time, the opportunity to undertake detailed studies of seeding and staging of the LWFA; proton acceleration to the 100-200 MeV level, which is essential for medical applications; and others.

Nuclear physics accelerator facilities

International Nuclear Information System (INIS)

1988-12-01

This paper describes many of the nuclear physics heavy-ion accelerator facilities in the US and the research programs being conducted. The accelerators described are: Argonne National Laboratory--ATLAS; Brookhaven National Laboratory--Tandem/AGS Heavy Ion Facility; Brookhaven National Laboratory--Relativistic Heavy Ion Collider (RHIC) (Proposed); Continuous Electron Beam Accelerator Facility; Lawrence Berkeley Laboratory--Bevalac; Lawrence Berkeley Laboratory--88-Inch Cyclotron; Los Alamos National Laboratory--Clinton P. Anderson Meson Physics Facility (LAMPF); Massachusetts Institute of Technology--Bates Linear Accelerator Center; Oak Ridge National Laboratory--Holifield Heavy Ion Research Facility; Oak Ridge National Laboratory--Oak Ridge Electron Linear Accelerator; Stanford Linear Accelerator Center--Nuclear Physics Injector; Texas AandM University--Texas AandM Cyclotron; Triangle Universities Nuclear Laboratory (TUNL); University of Washington--Tandem/Superconducting Booster; and Yale University--Tandem Van de Graaff

Analytical researches on the accelerating structures, wakefields, and beam dynamics for future linear colliders

International Nuclear Information System (INIS)

Gao, J.

1996-01-01

The research works presented in this memoir are oriented not only to the R and D programs towards future linear colliders, but also to the pedagogic purposes. The first part of this memoir (from Chapter 2 to Chapter 9) establishes an analytical framework of the disk-loaded slow wave accelerating structures with can be served as the advanced courses for the students who have got some basic trainings in the linear accelerator theories. The analytical formulae derived in this part describe clearly the properties of the disk-loaded accelerating structures, such as group velocity, shunt impedance, coupling coefficients κ and β, loss factors, and wake fields. The second part (from Chapter 11 to Chapter 13) gives the beam dynamics simulations and the final proposal of an S-Band Superconducting Linear Collider (SSLC) which is aimed to avoid the dark current problem in TESLA project. This memoir has not included all the works conducted since April 1992, such as beam dynamics simulations for CLIC Test Facility (CFT-2) and the design of High Charge Structures (HCS) (11π/12 mode) for CFT-2, in order to make this memoir more harmonious, coherent and continuous. (author)

Proposed Brookhaven accelerator-based neutron generator

International Nuclear Information System (INIS)

Grand, P.; Batchelor, K.; Chasman, R.; Rheaume, R.

1976-01-01

The d-Li Neutron Source concept, which includes a high-current dueteron linac, is an outgrowth of attempts made to use the BNL, 200-MeV proton linac BLIP facility to do radiation damage studies. It included a 100 mA, 30-MeV deuteron linear accelerator and a fast-flowing liquid lithium jet as the target. The latest design is not very different, except that the current is now 200 mA and the linac energy has been raised to 35 MeV. Both parameters, were changed to optimize the effectiveness of the facility with respect to flux, experimental volume and match to 14 MeV neutron-radiation-damage effects. The proposed Brookhaven Accelerator-based Neutron Generator is described with particular emphasis on the linear accelerator. The proposed facility is a practical and efficient way of producing the intense, high energy neutron beams needed for CTR material studies. The accelerator and liquid-metal technologies are well proven, state-of-the-art technologies. The fact that no new technology is required guarantees the possibility of meeting construction schedules, and more importantly, guarantees a high level of operational reliability

Acceleration of polarized proton beams

International Nuclear Information System (INIS)

Roser, T.

1998-01-01

The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator

Beam dynamics in linear colliders

International Nuclear Information System (INIS)

Ruth, R.D.

1990-09-01

In this paper, we discuss some basic beam dynamics issues related to obtaining and preserving the luminosity of a next generation linear collider. The beams are extracted from a damping ring and compressed in length by the first bunch compressor. They are then accelerated in a preaccelerator linac up to an energy appropriate for injection into a high gradient linac. In many designs this pre-acceleration is followed by another bunch compression to reach a short bunch. After acceleration in the linac, the bunches are finally focused transversely to a small spot. 27 refs., 1 fig

Design study of beam dynamics issues for 1 TeV next linear collider based upon the relativistic-klystron two-beam accelerator

International Nuclear Information System (INIS)

Li, H.; Goffeney, N.; Henestroza, E.; Sessler, A.; Yu, S.; Houck, T.; Westenskow, G.

1994-11-01

A design study has recently been conducted for exploring the feasibility of a relativistic-klystron two-beam accelerator (RK-TBA) system as a rf power source for a 1 TeV linear collider. The author present, in this paper, the beam dynamics part of this study. They have achieved in their design study acceptable transverse and longitudinal beam stability properties for the resulting high efficiency and low cost RK-TBA

Compensation of head-on beam-beam induced resonance driving terms and tune spread in the Relativistic Heavy Ion Collider

Directory of Open Access Journals (Sweden)

W. Fischer

2017-09-01

Full Text Available A head-on beam-beam compensation scheme was implemented for operation in the Relativistic Heavy Ion Collider (RHIC at Brookhaven National Laboratory [Phys. Rev. Lett. 115, 264801 (2015PRLTAO0031-900710.1103/PhysRevLett.115.264801]. The compensation consists of electron lenses for the reduction of the beam-beam induced tune spread, and a lattice for the minimization of beam-beam generated resonance driving terms. We describe the implementations of the lattice and electron lenses, and report on measurements of lattice properties and the effect of the electron lenses on the hadron beam.

Polarized proton collider at RHIC

International Nuclear Information System (INIS)

Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S.Y.; Luccio, A.; MacKay, W.W.; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.N.

2003-01-01

In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998, reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to √s=500 GeV

Introduction to colliding beams at Fermilab

International Nuclear Information System (INIS)

Thompson, J.

1994-10-01

The Fermi National Accelerator Laboratory is currently the site of the world's highest center-of-mass energy proton-antiproton colliding beam accelerator, the Tevatron. The CDF and D OE detectors each envelop one of two luminous regions in the collider, and are thus wholly dependent on the accelerator for their success. The Tevatron's high operating energy, reliability, and record setting integrated luminosity have allowed both experiments to make world-class measurements and defined the region of physics that each can explore. The following sections are an overview of the highlights of the accelerator operation and are compiled from many sources. The major sources for each section are listed at the beginning of that section

RADIATION PROTECTION FOR THE RELATIVISTIC HEAVY ION-COLLIDER AT THE BROOKHAVEN NATIONAL LABORATORY

International Nuclear Information System (INIS)

Musolino, S.V.; Stevens, A.J.

1999-01-01

The Relativistic Heavy Ion Collider (RHIC) is a high energy particle accelerator built to study basic nuclear physics. It consists of two counter-rotating beams of fully stripped gold ions that are accelerated in two rings to an energy of 100 GeV/nucleon. The rings consist of a circular lattice of superconducting magnets 3.8 km in circumference. The beams can be stored for a period of five to ten hours and brought into collision for experiments during that time. The first major physics objective when the facility goes into operation is to recreate a state of matter, the quark-gluon plasma, that has been predicted to have existed at a short time after the creation of the universe. There are only a few other high energy particle accelerators like RHIC in the world. The rules promulgated in the Code of Federal Regulations under the Atomic Energy Act do not cover prompt radiation from accelerators, nor are there any State regulations that govern the design and operation of a superconducting collider. Special design criteria for prompt radiation were developed to provide guidance for the design of radiation shielding

Reactor operations Brookhaven medical research reactor, Brookhaven high flux beam reactor informal monthly report

International Nuclear Information System (INIS)

Hauptman, H.M.; Petro, J.N.; Jacobi, O.

1995-04-01

This document is the April 1995 summary report on reactor operations at the Brookhaven Medical Research Reactor and the Brookhaven High Flux Beam Reactor. Ongoing experiments/irradiations in each are listed, and other significant operations functions are also noted. The HFBR surveillance testing schedule is also listed

Linear collider accelerator physics issues regarding alignment

International Nuclear Information System (INIS)

Seeman, J.T.

1990-01-01

The next generation of linear colliders will require more stringent alignment tolerances than those for the SLC with regard to the accelerating structures, quadrupoles, and beam position monitors. New techniques must be developed to achieve these tolerances. A combination of mechanical-electrical and beam-based methods will likely be needed

Next Linear Collider Test Accelerator conceptual design report

International Nuclear Information System (INIS)

1993-08-01

This document presents the scientific justification and the conceptual design for the open-quotes Next Linear Collider Test Acceleratorclose quotes (NLCTA) at SLAC. The goals of the NLCTA are to integrate the new technologies of X-band accelerator structures and rf systems being developed for the Next Linear Collider, to measure the growth of the open-quotes dark currentclose quotes generated by rf field emission in the accelerator, to demonstrate multi-bunch beam-loading energy compensation and suppression of higher-order deflecting modes, and to measure any transverse components of the accelerating field. The NLCTA will be a 42-meter-long beam line consisting, consecutively, of a thermionic-cathode gun, an X-band buncher, a magnetic chicane, six 1.8-meter-long sections of 11.4-GHz accelerator structure, and a magnetic spectrometer. Initially, the unloaded accelerating gradient will be 50 MV/m. A higher-gradient upgrade option eventually would increase the unloaded gradient to 100 MV/m

Development and applications of super high energy collider accelerators. Vol. 1

Energy Technology Data Exchange (ETDEWEB)

Abdelaziz, E M [National Center for Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo, (Egypt)

1996-03-01

This paper presents a review of cyclic accelerators and their energy limitations. A description is given of the phase stability principle and evaluation of the synchrotron, an accelerator without energy limitation. Then the concept of colliding beams emerged to yield doubling of the beam energy as in the Tevatron 2 trillion electron volts (TeV) proton collider at Fermilab, and the large harden collider (LHD) which is now planned as a 14-TeV machine in the 27 Kilometer tunnel of the large electron positron (LEP) collider at CERN. Then presentation is given of the superconducting supercollider (SSC), a giant accelerator complex with energy 40-TeV in a tunnel 87 Kilometers in circumference under the country surrounding Waxahachile in Texas, U.S.A. These superhigh energy accelerators are intended to smash protons against protons at energy sufficient to reveal the nature of matter and to consolidate the prevailing general theory of elementary particles. 12 figs., 1 tab.

Development and applications of super high energy collider accelerators. Vol. 1

International Nuclear Information System (INIS)

Abdelaziz, E.M.

1996-01-01

This paper presents a review of cyclic accelerators and their energy limitations. A description is given of the phase stability principle and evaluation of the synchrotron, an accelerator without energy limitation. Then the concept of colliding beams emerged to yield doubling of the beam energy as in the Tevatron 2 trillion electron volts (TeV) proton collider at Fermilab, and the large harden collider (LHD) which is now planned as a 14-TeV machine in the 27 Kilometer tunnel of the large electron positron (LEP) collider at CERN. Then presentation is given of the superconducting supercollider (SSC), a giant accelerator complex with energy 40-TeV in a tunnel 87 Kilometers in circumference under the country surrounding Waxahachile in Texas, U.S.A. These superhigh energy accelerators are intended to smash protons against protons at energy sufficient to reveal the nature of matter and to consolidate the prevailing general theory of elementary particles. 12 figs., 1 tab

NLC. A test accelerator for the next linear collider

International Nuclear Information System (INIS)

Ruth, R.D.; Adolphsen, C.; Bane, K.; Boyce, R.F.; Burke, D.L.; Callin, R.; Caryotakis, G.; Cassel, R.; Clark, S.L.; Deruyter, H.; Fant, K.; Fuller, R.; Heifets, S.; Hoag, H.; Humphrey, R.; Kheifets, S.; Koontz, R.; Kroll, N.M.; Lavine, T.; Loew, G.A.; Menegat, A.; Miller, R.H.; Nantista, C.; Paterson, J.M.; Pearson, C.; Phillips, R.; Rifkin, J.; Spencer, J.; Tantawi, S.; Thompson, K.A.; Vlieks, A.; Vylet, V.; Wang, J.W.; Wilson, P.B.; Yeremian, A.; Youngman, B.

1993-01-01

At SLAC, we are pursuing the design of a Next Linear Collider (NLC) which would begin with a center-of-mass energy of 0.5 TeV, and be upgradable to at least 1.0 TeV. To achieve this high energy, we have been working on the development of a high-gradient 11.4-GHz (X-band) linear accelerator for the main linac of the collider. In this paper, we present the design of a 'Next Linear Collider Test Accelerator' (NLCTA). The goal of the NLCTA is to incorporate the new technologies of X-band accelerator structures, RF pulse compression systems and klystrons into a short linac which will then be a test bed for beam dynamics issues related to high-gradient acceleration. (orig.)

Evaluation of CBA first string full cell vacuum system

International Nuclear Information System (INIS)

Foerster, C.L.; Briggs, J.; Christianson, C.; Stattel, P.

1983-01-01

The CBA (Colliding Beam Accelerator, formerly known as ISABELLE) Full Cell Magnet System consisting of six superconducting dipole magnets and two superconducting quadrupole magnets requires two separate vacuum systems. One, known as beam vacuum operates below 3 x 10 -11 Torr and the other, known as insulating vacuum, operates at less than 10 -7 Torr to isolate cryo circuits from atmosphere and from the uhv beam tubes. The uhv bore tube is isolated from the 4.0 0 K magnet by thirty-six (36) layers of superinsulation and insulating vacuum. Heat load measurements on the bore tube have been completed and found to agree with data obtained in smaller controlled experiments. Measurements of helium, accumulated on cryogenic pumped charcoal panels over many weeks, have verified sensitive helium mass spectrometer leak detection methods for vacuum integrity, providing sound design of the welded complex. The Full Cell was assembled and operated under conditions that would exist in the completed machine. Pressures below 2 x 10 -11 Torr beam vacuum requirement and below 2 x 10 -7 Torr insulating vacuum, were routinely achieved during all phases of the Full Cell operation and support systems testing

An $ep$ collider based on proton-driven plasma wakefield acceleration

CERN Document Server

Wing, M.; Mete, O.; Aimidula, A.; Welsch, C.; Chattopadhyay, S.; Mandry, S.

2014-01-01

Recent simulations have shown that a high-energy proton bunch can excite strong plasma wakefields and accelerate a bunch of electrons to the energy frontier in a single stage of acceleration. This scheme could lead to a future $ep$ collider using the LHC for the proton beam and a compact electron accelerator of length 170 m, producing electrons of energy up to 100 GeV. The parameters of such a collider are discussed as well as conceptual layouts within the CERN accelerator complex. The physics of plasma wakefield acceleration will also be introduced, with the AWAKE experiment, a proof of principle demonstration of proton-driven plasma wakefield acceleration, briefly reviewed, as well as the physics possibilities of such an $ep$ collider.

The Next Linear Collider Test Accelerator

International Nuclear Information System (INIS)

Ruth, R.D.; Adolphsen, C.; Bane, K.

1993-04-01

During the past several years, there has been tremendous progress the development of the RF system and accelerating structures for a Next Linear Collider (NLC). Developments include high-power klystrons, RF pulse compression systems and damped/detuned accelerator structures to reduce wakefields. In order to integrate these separate development efforts into an actual X-band accelerator capable of accelerating the electron beams necessary for an NLC, we are building an NLC Test Accelerator (NLCTA). The goal of the NLCTA is to bring together all elements of the entire accelerating system by constructing and reliably operating an engineered model of a high-gradient linac suitable for the NLC. The NLCTA will serve as a testbed as the design of the NLC evolves. In addition to testing the RF acceleration system, the NLCTA is designed to address many questions related to the dynamics of the beam during acceleration. In this paper, we will report oil the status of the design, component development, and construction of the NLC Test Accelerator

The beam-beam limit in asymmetric colliders: Optimization of the B-factory parameter base

International Nuclear Information System (INIS)

Tennyson, J.L.

1990-01-01

This paper presents a general theory of the beam-beam limit in symmetric and asymmetric lepton ring colliders. It shows how the beam-beam limit in these accelerators affects the maximum attainable luminosity and presents a specific algorithm for parameter base optimization. It is shown that the special problems inherent in asymmetric colliders derive not from the asymmetry, but from the fact that the two beams must be in different rings. Computer simulation experiments are used to demonstrate the various phenomena discussed in the theory

Beam Induced Hydrodynamic Tunneling in the Future Circular Collider Components

CERN Document Server

AUTHOR|(CDS)2083092; Burkart, Florian; Schmidt, Rudiger; Shutov, A; Wollmann, Daniel; Piriz, A

2016-01-01

A future circular collider (FCC) has been proposed as a post-Large Hadron Collider accelerator, to explore particle physics in unprecedented energy ranges. The FCC is a circular collider in a tunnel with a circumference of 80–100 km. The FCC study puts an emphasis on proton-proton high-energy and electron-positron high-intensity frontier machines. A proton-electron interaction scenario is also examined. According to the nominal FCC parameters, each of the 50 TeV proton beams will carry an amount of 8.5 GJ energy that is equivalent to the kinetic energy of an Airbus A380 (560 t) at a typical speed of 850  km/h . Safety of operation with such extremely energetic beams is an important issue, as off-nominal beam loss can cause serious damage to the accelerator and detector components with a severe impact on the accelerator environment. In order to estimate the consequences of an accident with the full beam accidently deflected into equipment, we have carried out numerical simulations of interaction of a FCC...

A microwiggler Free-Electron Laser at the Brookhaven Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Fernow, R.; Gallardo, J.; Kirk, H.; Pellegrini, C.; van Steenbergen, A.; Bhowmik, A.; Rockwell International Corp., Canoga Park, CA

1989-01-01

We report the design and status of an FEL experiment at the Brookhaven National Laboratory Accelerator Test Facility. A 50 MeV high brightness electron beam will be utilized for an oscillator experiment in the visible wavelength region. The microwiggler to be used is a superferric planar undulator with a 0.88 cm period, 60 cm length and K = 0.35. The optical cavity is a 368 cm long stable resonator with broadband dielectric coated mirrors. 8 refs., 2 figs., 4 tabs

A test accelerator for the next linear collider

International Nuclear Information System (INIS)

Ruth, R.D.; Adolphsen, C.; Bane, K.; Boyce, R.F.; Burke, D.L.; Callin, R.; Caryotakis, G.; Cassel, R.; Clark, S.L.; Deruyter, H.; Fant, K.; Fuller, R.; Heifets, S.; Hoag, H.; Humphrey, R.; Kheifets, S.; Koontz, R.; Lavine, T.; Loew, G.A.; Menegat, A.; Miller, R.H.; Paterson, J.M.; Pearson, C.; Phillips, R.; Rifkin, J.; Spencer, J.; Tantawi, S.; Thompson, K.A.; Vlieks, A.; Vylet, V.; Wang, J.W.; Wilson, P.B.; Yeremian, A.; Youngman, B.; Kroll, N.M.; Nantista, C.

1993-07-01

At SLAC, the authors are pursuing the design of a Next Linear Collider (NLC) which would begin with a center-of-mass energy of 0.5 TeV, and be upgradable to at least 1.0 TeV. To achieve this high energy, they have been working on the development of a high-gradient 11.4-GHz (X-band) linear accelerator for the main linac of the collider. In this paper, they present the design of a open-quotes Next Linear Collider Test Acceleratorclose quotes (NLCTA). The goal of the NLCTA is to incorporate the new technologies of X-band accelerator structures, RF pulse compression systems and klystrons into a short linac which will then be a test bed for beam dynamics issues related to high-gradient acceleration

High Energy Accelerator and Colliding Beam User Group: Progress report, March 1, 1988--February 28, 1989

International Nuclear Information System (INIS)

1988-09-01

This report discusses work carried out by the High Energy Accelerator and Colliding Beam User Group at the University of Maryland. Particular topics discussed are: OPAL experiment at LEP; deep inelastic muon interactions; B physics with the CLEO detector at CESR; further results from JADE; and search for ''small'' violation of the Pauli principle

Acceleration of polarized protons and deuterons in the ion collider ring of JLEIC

Science.gov (United States)

Kondratenko, A. M.; Kondratenko, M. A.; Filatov, Yu N.; Derbenev, Ya S.; Lin, F.; Morozov, V. S.; Zhang, Y.

2017-07-01

The figure-8-shaped ion collider ring of Jefferson Lab Electron-Ion Collider (JLEIC) is transparent to the spin. It allows one to preserve proton and deuteron polarizations using weak stabilizing solenoids when accelerating the beam up to 100 GeV/c. When the stabilizing solenoids are introduced into the collider’s lattice, the particle spins precess about a spin field, which consists of the field induced by the stabilizing solenoids and the zero-integer spin resonance strength. During acceleration of the beam, the induced spin field is maintained constant while the resonance strength experiences significant changes in the regions of “interference peaks”. The beam polarization depends on the field ramp rate of the arc magnets. Its component along the spin field is preserved if acceleration is adiabatic. We present the results of our theoretical analysis and numerical modeling of the spin dynamics during acceleration of protons and deuterons in the JLEIC ion collider ring. We demonstrate high stability of the deuteron polarization in figure-8 accelerators. We analyze a change in the beam polarization when crossing the transition energy.

The CERN Antiproton Collider Programme Accelerators and Accumulation Rings

CERN Document Server

Koziol, Heribert

2004-01-01

One of CERN's most daring and successful undertakings was the quest for the intermediate bosons, W and Z. In this paper, we describe the accelerator part of the venture which relied on a number of innovations: an extension of the budding method of stochastic cooling by many orders of magnitude; the construction of the Antiproton Accumulator, depending on several novel accelerator methods and technologies; major modifications to the 26 GeV PS Complex; and the radical conversion of the 300 GeV SPS, which just had started up as an accelerator, to a protonâ€"antiproton collider. The SPS Collider had to master the beamâ€"beam effect far beyond limits reached ever before and had to function in a tight symbiosis with the huge detectors UA1 and UA2.

Laser ion source with solenoid for Brookhaven National Laboratory-electron beam ion source.

Science.gov (United States)

Kondo, K; Yamamoto, T; Sekine, M; Okamura, M

2012-02-01

The electron beam ion source (EBIS) preinjector at Brookhaven National Laboratory (BNL) is a new heavy ion-preinjector for relativistic heavy ion collider (RHIC) and NASA Space Radiation Laboratory (NSRL). Laser ion source (LIS) is a primary ion source provider for the BNL-EBIS. LIS with solenoid at the plasma drift section can realize the low peak current (∼100 μA) with high charge (∼10 nC) which is the BNL-EBIS requirement. The gap between two solenoids does not cause serious plasma current decay, which helps us to make up the BNL-EBIS beamline.

Laser ion source with solenoid for Brookhaven National Laboratory-electron beam ion source

International Nuclear Information System (INIS)

Kondo, K.; Okamura, M.; Yamamoto, T.; Sekine, M.

2012-01-01

The electron beam ion source (EBIS) preinjector at Brookhaven National Laboratory (BNL) is a new heavy ion-preinjector for relativistic heavy ion collider (RHIC) and NASA Space Radiation Laboratory (NSRL). Laser ion source (LIS) is a primary ion source provider for the BNL-EBIS. LIS with solenoid at the plasma drift section can realize the low peak current (∼100 μA) with high charge (∼10 nC) which is the BNL-EBIS requirement. The gap between two solenoids does not cause serious plasma current decay, which helps us to make up the BNL-EBIS beamline.

Laser ion source with solenoid for Brookhaven National Laboratory-electron beam ion sourcea)

Science.gov (United States)

Kondo, K.; Yamamoto, T.; Sekine, M.; Okamura, M.

2012-02-01

The electron beam ion source (EBIS) preinjector at Brookhaven National Laboratory (BNL) is a new heavy ion-preinjector for relativistic heavy ion collider (RHIC) and NASA Space Radiation Laboratory (NSRL). Laser ion source (LIS) is a primary ion source provider for the BNL-EBIS. LIS with solenoid at the plasma drift section can realize the low peak current (˜100 μA) with high charge (˜10 nC) which is the BNL-EBIS requirement. The gap between two solenoids does not cause serious plasma current decay, which helps us to make up the BNL-EBIS beamline.

Two-Beam Linear Colliders - Special Issues

CERN Document Server

Corsini, Roberto

2010-01-01

The path towards a multi-TeV e+e- linear collider proposed by the CLIC study is based on the Two-Beam Acceleration (TBA) scheme. Such a scheme is promising in term of efficiency, reliability and cost. The rationale behind the two-beam scheme is discussed in the paper, together with the special issues related to this technology and the R&D needed to demonstrate its feasibility.

Radio frequency systems for present and future accelerators

International Nuclear Information System (INIS)

Raka, E.C.

1987-01-01

Rf systems are described for the FNAL Main Ring and Tevatron Ring, CERN SPS and LEP, and HERA proton acceleration system, CERN PS e + e/sup minus/ acceleration system, and CERN EPA monochromatic cavity. Low impedance rf systems in CERN ISR, the Brookhaven CBA, and SSC are also discussed

Beam dynamics verification in linacs of linear colliders

International Nuclear Information System (INIS)

Seeman, J.T.

1989-01-01

The SLAC two-mile linac has been upgraded to accelerate high current, low emittance electron and positron beams to be used in the SLAC Linear Collider (SLC). After the upgrade was completed, extensive beam studies were made to verify that the design criteria have been met. These tests involved the measurement of emittance, beam phase space orientation, energy dispersion, trajectory oscillations, bunch length, energy spectrum and wakefields. The methods, the systems and the data cross checks are compared for the various measurements. Implications for the next linear collider are discussed. 12 refs., 13 figs., 2 tabs

9th International Accelerator School for Linear Colliders

CERN Document Server

2015-01-01

This school is a continuation of the series of schools that began nine years ago: Japan 2006, Italy 2007, United States 2008, China 2009, Switzerland 2010, United States 2011, India 2012 and Turkey 2013. Based on needs from the accelerator community, the Linear Collider Collaboration (LCC) and ICFA Beam Dynamics Panel are organising the Ninth International Accelerator School for Linear Colliders. The school will present instruction in TeV-scale linear colliders including the ILC, CLIC and other advanced accelerators. An important change of this year’s school from previous LC schools is that it will also include the free electron laser (FEL), a natural extension for applications of the ILC/CLIC technology. The school is offered to graduate students, postdoctoral fellows and junior researchers from around the world. We welcome applications from physicists who are considering changing to a career in accelerator physics and technology. This school adopts an in depth approach. A selective course on the FEL has b...

Head-On Beam-Beam Interactions in High-Energy Hadron Colliders. GPU-Powered Modelling of Nonlinear Effects

CERN Document Server

AUTHOR|(CDS)2160109; Støvneng, Jon Andreas

2017-08-15

The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strength of the beam-beam interactions will be higher after the upgrade to the High-Luminosity Large Hadron Collider, and also in the next generation of machines, as the Future Circular Hadron Collider. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and drives resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. For this thesis, a new code named CABIN (Cuda-Accelerated Beam-beam Interaction) has been developed to study the limitations caused by the impact of strong beam-beam interactions. In particular, the evolution of the beam emittance and beam intensity has been monitored to study the impact quantitatively...

The Next Generation of Heavy Ion Sources (447th Brookhaven Lecture)

International Nuclear Information System (INIS)

Okamura, Masahiro

2009-01-01

Imagine if, by staying in your lane when driving on the expressway, you could help fight cancer or provide a new, clean energy source. You would clench the steering wheel with both hands and stay in your lane, right? Unlike driving on the expressway where you intentionally avoid hitting other cars, scientists sometimes work to steer particle beams into head-on collisions with other oncoming particle beams. However, the particles must be kept 'in their lanes' for cleaner, more frequent collisions. Some scientists propose starting the whole process by using lasers to heat a fixed target as a way to get particles with higher charge, which are more steerable. These scientists believe the new methods could be used to develop particle beams for killing cancer cells or creating usable energy from fusion. Join Masahiro Okamura of Brookhaven's Collider-Accelerator Department for the 447th Brookhaven Lecture, titled 'The Next Generation of Heavy Ion Sources.' Okamura will explain how lasers can be used to create plasma, neutral mixtures of positive ions and negative electrons, from different materials, and how using this plasma leads to beams with higher charge states and currents. He will also discuss how this efficient, simpler method of producing particle beams might be used for cancer therapy, to develop new energy sources, or in synchrotrons.

Vacuum laser acceleration using a radially polarized CO sub 2 laser beam

CERN Document Server

Liu, Y; He, P

1999-01-01

Utilizing the high-power, radially polarized CO sub 2 laser and high-quality electron beam at the Brookhaven Accelerator Test Facility, a vacuum laser acceleration scheme is proposed. In this scheme, optics configuration is simple, a small focused beam spot size can be easily maintained, and optical damage becomes less important. At least 0.5 GeV/m acceleration gradient is achievable by 1 TW laser power.

Injection of electrons by colliding laser pulses in a laser wakefield accelerator

Energy Technology Data Exchange (ETDEWEB)

Hansson, M., E-mail: martin.hansson@fysik.lth.se; Aurand, B.; Ekerfelt, H.; Persson, A.; Lundh, O.

2016-09-01

To improve the stability and reproducibility of laser wakefield accelerators and to allow for future applications, controlling the injection of electrons is of great importance. This allows us to control the amount of charge in the beams of accelerated electrons and final energy of the electrons. Results are presented from a recent experiment on controlled injection using the scheme of colliding pulses and performed using the Lund multi-terawatt laser. Each laser pulse is split into two parts close to the interaction point. The main pulse is focused on a 2 mm diameter gas jet to drive a nonlinear plasma wave below threshold for self-trapping. The second pulse, containing only a fraction of the total laser energy, is focused to collide with the main pulse in the gas jet under an angle of 150°. Beams of accelerated electrons with low divergence and small energy spread are produced using this set-up. Control over the amount of accelerated charge is achieved by rotating the plane of polarization of the second pulse in relation to the main pulse. Furthermore, the peak energy of the electrons in the beams is controlled by moving the collision point along the optical axis of the main pulse, and thereby changing the acceleration length in the plasma. - Highlights: • Compact colliding pulse injection set-up used to produce low energy spread e-beams. • Beam charge controlled by rotating the polarization of injection pulse. • Peak energy controlled by point of collision to vary the acceleration length.

Advances in beam physics and technology: Colliders of the future

Energy Technology Data Exchange (ETDEWEB)

Chattopadhyay, S.

1994-11-01

Beams may be viewed as directed and focussed flow of energy and information, carried by particles and electromagnetic radiation fields (ie, photons). Often, they interact with each other (eg, in high energy colliders) or with other forms of matter (eg, in fixed targets, sychrotron radiation, neutron scattering, laser chemistry/physics, medical therapy, etc.). The whole art and science of beams revolve around the fundamental quest for, and ultimate implementation of, mechanisms of production, storage, control and observation of beams -- always directed towards studies of the basic structures and processes of the natural world and various practical applications. Tremendous progress has been made in all aspects of beam physics and technology in the last decades -- nonlinear dynamics, superconducting magnets and rf cavities, beam instrumentation and control, novel concepts and collider praradigms, to name a few. We illustrate this progress with a few examples and remark on the emergence of new collider scenarios where some of these progress might come to use -- the Gamma-Gamma Collider, the Muon Collider, laser acceleration, etc. We close with an outline of future oppotunities and outlook.

Advances in beam physics and technology: Colliders of the future

International Nuclear Information System (INIS)

Chattopadhyay, S.

1994-11-01

Beams may be viewed as directed and focussed flow of energy and information, carried by particles and electromagnetic radiation fields (ie, photons). Often, they interact with each other (eg, in high energy colliders) or with other forms of matter (eg, in fixed targets, sychrotron radiation, neutron scattering, laser chemistry/physics, medical therapy, etc.). The whole art and science of beams revolve around the fundamental quest for, and ultimate implementation of, mechanisms of production, storage, control and observation of beams -- always directed towards studies of the basic structures and processes of the natural world and various practical applications. Tremendous progress has been made in all aspects of beam physics and technology in the last decades -- nonlinear dynamics, superconducting magnets and rf cavities, beam instrumentation and control, novel concepts and collider praradigms, to name a few. We illustrate this progress with a few examples and remark on the emergence of new collider scenarios where some of these progress might come to use -- the Gamma-Gamma Collider, the Muon Collider, laser acceleration, etc. We close with an outline of future oppotunities and outlook

Beam trajectory acquisition system for the arcs of the Stanford Linear Collider

International Nuclear Information System (INIS)

Pellegrin, J.L.; Ross, M.C.; Scott, B.D.; Wilson, D.S.

1987-02-01

This report describes the beam position monitoring system of the collider arcs at the Stanford Linear Collider. This beam position monitoring system is different from others at SLAC in its large amount of hardware and its use of ungated, self-triggered electronics. All of the processing electronics are installed in the accelerator tunnel

POLARIZED BEAMS: 2 - Partial Siberian Snake rescues polarized protons at Brookhaven

International Nuclear Information System (INIS)

Huang, Haixin

1994-01-01

To boost the level of beam polarization (spin orientation), a partial 'Siberian Snake' was recently used to overcome imperfection depolarizing resonances in the Brookhaven Alternating Gradient Synchrotron (AGS). This 9-degree spin rotator recently permitted acceleration with no noticeable polarization loss. The intrinsic AGS depolarizing resonances (which degrade the polarization content) had been eliminated by betatron tune jumps, but the imperfection resonances were compensated by means of harmonic orbit corrections. However, at high energies these orbit corrections are difficult and tedious and a Siberian Snake became an attractive alternative

MEQALAC development at Brookhaven

International Nuclear Information System (INIS)

Gammel, G.; Brodowski, J.; Keane, J.; Maschke, A.; Meier, E.; Mobley, R.; Sanders, R.

1981-01-01

A novel method of transporting and accelerating high brightness ion beams, called MEQALAC, has been developed at Brookhaven. The concept and its motivation will be described first, with reference to other sources for detail, and then the performance of two operating MEQALAC's will be presented

Proton-proton colliding beam facility ISABELLE

International Nuclear Information System (INIS)

Hahn, H.

1980-01-01

This paper attempts to present the status of the ISABELLE construction project, which has the objective of building a 400 + 400 GeV proton colliding beam facility. The major technical features of the superconducting accelerators with their projected performance are described. Progress made so far, difficulties encountered, and the program until completion in 1986 is briefly reviewed

TRISTAN, electron-positron colliding beam project

International Nuclear Information System (INIS)

1987-03-01

In this report e + e - colliding beam program which is now referred to as TRISTAN Project will be described. A brief chronology and outline of TRISTAN Project is given in Chapter 1. Chapter 2 of this article gives a discussion of physics objectives at TRISTAN. Chapter 3 treats the overall description of the accelerators. Chapter 4 describes design of each of the accelerator systems. In Chapter 5, detector facilities are discussed in some detail. A description of accelerator tunnels, experimental areas, and utilities are given in Chapter 6. In the Appendix, the publications on the TRISTAN Project are listed. (author)

Correlation of superconductor strand, cable, and dipole critical currents in CBA magnets

International Nuclear Information System (INIS)

Tannenbaum, M.J.; Garber, M.; Sampson, W.B.

1982-01-01

A calibration between vendor critical current data for 0.0268'' diameter superconductor strand supplied to Fermilab, and the BNL 10 -12 Ωcm critical current specification is presented. Vendor critical current data for over 400 Fermilab type billets are shown, both as supplied by the vendor and converted to BNL units. Predictions of cable critical current are made using the sum of the critical currents of the 23 strands, where all strands from the same half billet are assigned the same critical current. The measured critical current shows excellent correlation to the predicted value and is approximately 14 +- 2 percent below it. Colliding Beam Accelerator (CBA) full length dipoles reach the conductor critical current limit, essentially without training. Magnet performance is predictable from the measured critical current of a short sample of cable to within 2%

Accelerating and storing polarized hadron beams

International Nuclear Information System (INIS)

Teng, L.C.

1990-10-01

Polarization hadron experiments at high energies continue to generate surprises. Many questions remain unanswered or unanswerable within the frame work of QCD. These include such basic questions as to why at high energies the polarization analyzing power in pp elastic scattering remains high, why hyperons are produced with high polarizations etc. It is, therefore, interesting to investigate the possibilities of accelerating and storing polarized beams in high energy colliders. On the technical side the recent understanding and confirmation of the actions of partial and multiple Siberian snakes made it possible to contemplate accelerating and storing polarized hadron beams to multi-TeV energies. In this paper, we will examine the equipment, the operation and the procedure required to obtain colliding beams of polarized protons at TeV energies

Beam parameter measurements for the SLAC linear collider

International Nuclear Information System (INIS)

Clendenin, J.E.; Blocker, C.; Breidenbach, M.

1982-01-01

A stable, closely-controlled, high-intensity, single-bunch beam will be required for the SLAC Linear Collider. The characteristics of short-pulse, low-intensity beams in the SLAC linac have been studied. A new, high-intensity thermionic gun, subharmonic buncher and S-band buncher/accelerator section were installed recently at SLAC. With these components, up to 10 11 electrons in a single S-band bunch are available for injection into the linac. the first 100-m accelerator sector has been modified to allow control of short-pulse beams by a model-driven computer program. Additional instrumentation, including a computerized energy analyzer and emittance monitor have been added at the end of the 100-m sector. The beam intensity, energy spectrum, emittance, charge distribution and the effect of wake fields in the first accelerator sector have been measured. The new source and beam control system will be described and the most recent results of the beam parameter measurements will be discussed

Applications of electron lenses: scraping of high-power beams, beam-beam compensation, and nonlinear optics

Energy Technology Data Exchange (ETDEWEB)

Stancari, Giulio

2014-09-11

Electron lenses are pulsed, magnetically confined electron beams whose current-density profile is shaped to obtain the desired effect on the circulating beam. Electron lenses were used in the Fermilab Tevatron collider for bunch-by-bunch compensation of long-range beam-beam tune shifts, for removal of uncaptured particles in the abort gap, for preliminary experiments on head-on beam-beam compensation, and for the demonstration of halo scraping with hollow electron beams. Electron lenses for beam-beam compensation are being commissioned in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Hollow electron beam collimation and halo control were studied as an option to complement the collimation system for the upgrades of the Large Hadron Collider (LHC) at CERN; a conceptual design was recently completed. Because of their electric charge and the absence of materials close to the proton beam, electron lenses may also provide an alternative to wires for long-range beam-beam compensation in LHC luminosity upgrade scenarios with small crossing angles. At Fermilab, we are planning to install an electron lens in the Integrable Optics Test Accelerator (IOTA, a 40-m ring for 150-MeV electrons) as one of the proof-of-principle implementations of nonlinear integrable optics to achieve large tune spreads and more stable beams without loss of dynamic aperture.

Beam Dynamics Simulation for the CTF3 Drive Beam Accelerator

CERN Document Server

Schulte, Daniel

2000-01-01

A new CLIC Test Facility (CTF3) at CERN will serve to study the drive beam generation for the Compact Linear Collider (CLIC). CTF3 has to accelerate a 3.5 A electron beam in almost fully-loaded structures. The pulse contains more than 2000 bunches, one in every second RF bucket, and has a length of more than one microsecond. Different options for the lattice of the drive-beam accelerator are presented, based on FODO-cells and triplets as well as solenoids. The transverse stability is simulated, including the effects of beam jitter, alignment and beam-based correction.

Description of the intense, low energy, monoenergetic positron beam at Brookhaven

International Nuclear Information System (INIS)

Lynn, K.G.; Mills, A.P. Jr.; Roellig, L.O.; Weber, M.

1985-01-01

An intense (4 x 10 7 s -1 ), low energy (approx. =1.0 eV), monoenergetic (ΔE approx. = 75 MeV) beam of positrons has been built at the Brookhaven National Laboratory. This flux is more than 10 times greater than any existing beam from radioactive sources. Plans are underway to increase further the flux by more than an order of magnitude. The intense low energy positron beam is made by utilizing the High Flux Beam Reactor at Brookhaven to produce the isotope 64 Cu with an activity of 40 curies of positrons. Source moderation techniques are utilized to produce the low energy positron beam from the high energy positrons emitted from 64 Cu. 31 refs., 7 figs

Seventh International Accelerator School for Linear Colliders

CERN Document Server

Organizers of the Seventh International Accelerator School for Linear Colliders

2012-01-01

We are pleased to announce the Seventh International Accelerator School for Linear Colliders. This school is a continuation of the series of schools which began six years ago.  The first school was held in 2006 in Sokendai, Japan, the second in 2007 in Erice, Italy, the third in 2008 in Oakbrook Hills, USA, the fourth in 2009 in Huairou, China, the fifth in 2010 in Villars-sur-Ollon, Switzerland, and the sixth in 2011 in Pacific Grove, USA.   The school is organized by the International Linear Collider (ILC) Global Design Effort (GDE), the Compact Linear Collider (CLIC) and the International Committee for Future Accelerators (ICFA) Beam Dynamics Panel. The school this year will take place at the Radisson Blu Hotel, Indore, India from November 27 to December 8, 2012. It is hosted by the Raja Ramanna Center for Advanced Technology (RRCAT) and sponsored by a number of funding agencies and institutions around the world including the U.S. Department of Energy (DOE), the U.S. National Science...

ISABELLE: a proton-proton colliding beam facility. [Proposal for the construction of ISABELLE

Energy Technology Data Exchange (ETDEWEB)

None

1977-04-01

A proposal is presented for the construction of an Intersecting Storage Accelerator, ISABELLE, to be located at Brookhaven National Laboratory. At this major research facility, colliding beams of protons will be produced and studied by particle physicists. This proposal combines the interests of these particle physicists in exploring a new energy regime with the challenge of building a new research instrument. The proposal results from several years of considering such devices in parallel with extensive developmental work. The proposal is divided into several major parts. Following an introduction is an overall summary of the proposal covering its highlights. Part II contains a thorough discussion of the physics objectives that can be addressed by the storage ring. It begins with an explanation of current theoretical concepts that occupy the curiosity of high energy physicists. Then follows a brief discussion of possible experiments that might be assembled at the interaction regions to test these concepts. The third part of the proposal goes into the details of the design of the intersecting storage accelerators. It begins with a description of the entire facility and the design of the magnet ring structure. The processes of proton beam accumulation and acceleration are thoroughly described. The discussion then turns to the design of the components and subsystems for the accelerator. The accelerator elements are described followed by a description of the physical plant. The cost estimate and time scales are displayed in Part IV. Here the estimate has been based on the experience gained from working with the prototype units at the laboratory. The appendices are an important part of the proposal. The parameter list for the 200 x 200 GeV ISABELLE is carefully documented. An example of a possible research program can be found in an appendix. The performance of prototype units is documented in one of the appendices.

Advances in beam physics and technology: Colliders of the future

Science.gov (United States)

Chattopadhyay, Swapan

1996-02-01

Beams may be viewed as directed and focussed flow of energy and information, carried by particles and electromagnetic radiation fields (i.e. photons). Often, they are brought into interaction with each other (e.g. in high energy colliders) or with other forms of matter (e.g. in fixed target physics, synchrotron radiation sciences, neutron scattering experiments, laser chemistry and physics, medical therapy, etc.). The whole art and science of beams revolve around the fundamental quest for, and ultimate implementation of, mechanisms of production, storage, control and observation of beams—always directed towards studies of the basic structures and processes of the natural world and various practical applications. Tremendous progress has been made in all aspects of beam physics and technology in the last decades—nonlinear dynamics, superconducting magnets and radio frequency cavities, beam instrumentation and control, novel concepts and collider paradigms, to name a few. We will illustrate this progress via a few examples and remark on the emergence of new collider scenarios where some of these progress might come to use—the Gamma-Gamma Collider, the Muon Collider, laser acceleration, etc. We will close with an outline of future opportunities and outlook.

Beam induced hydrodynamic tunneling in the future circular collider components

Directory of Open Access Journals (Sweden)

N. A. Tahir

2016-08-01

Full Text Available A future circular collider (FCC has been proposed as a post-Large Hadron Collider accelerator, to explore particle physics in unprecedented energy ranges. The FCC is a circular collider in a tunnel with a circumference of 80–100 km. The FCC study puts an emphasis on proton-proton high-energy and electron-positron high-intensity frontier machines. A proton-electron interaction scenario is also examined. According to the nominal FCC parameters, each of the 50 TeV proton beams will carry an amount of 8.5 GJ energy that is equivalent to the kinetic energy of an Airbus A380 (560 t at a typical speed of 850  km/h. Safety of operation with such extremely energetic beams is an important issue, as off-nominal beam loss can cause serious damage to the accelerator and detector components with a severe impact on the accelerator environment. In order to estimate the consequences of an accident with the full beam accidently deflected into equipment, we have carried out numerical simulations of interaction of a FCC beam with a solid copper target using an energy-deposition code (fluka and a 2D hydrodynamic code (big2 iteratively. These simulations show that, although the penetration length of a single FCC proton and its shower in solid copper is about 1.5 m, the full FCC beam will penetrate up to about 350 m into the target because of the “hydrodynamic tunneling.” These simulations also show that a significant part of the target is converted into high-energy-density matter. We also discuss this interesting aspect of this study.

Beam Induced Hydrodynamic Tunneling in the Future Circular Collider Components

Science.gov (United States)

Tahir, N. A.; Burkart, F.; Schmidt, R.; Shutov, A.; Wollmann, D.; Piriz, A. R.

2016-08-01

A future circular collider (FCC) has been proposed as a post-Large Hadron Collider accelerator, to explore particle physics in unprecedented energy ranges. The FCC is a circular collider in a tunnel with a circumference of 80-100 km. The FCC study puts an emphasis on proton-proton high-energy and electron-positron high-intensity frontier machines. A proton-electron interaction scenario is also examined. According to the nominal FCC parameters, each of the 50 TeV proton beams will carry an amount of 8.5 GJ energy that is equivalent to the kinetic energy of an Airbus A380 (560 t) at a typical speed of 850 km /h . Safety of operation with such extremely energetic beams is an important issue, as off-nominal beam loss can cause serious damage to the accelerator and detector components with a severe impact on the accelerator environment. In order to estimate the consequences of an accident with the full beam accidently deflected into equipment, we have carried out numerical simulations of interaction of a FCC beam with a solid copper target using an energy-deposition code (fluka) and a 2D hydrodynamic code (big2) iteratively. These simulations show that, although the penetration length of a single FCC proton and its shower in solid copper is about 1.5 m, the full FCC beam will penetrate up to about 350 m into the target because of the "hydrodynamic tunneling." These simulations also show that a significant part of the target is converted into high-energy-density matter. We also discuss this interesting aspect of this study.

Detectors for CBA

International Nuclear Information System (INIS)

Baggett, N.; Gordon, H.A.; Palmer, R.B.; Tannenbaum, M.J.

1983-05-01

We discuss some current approaches to a large solid angle detector. An alternative approach for utilizing the high rate of events at CBA is to design special purpose detectors for specific physics goals which can be pursued within a limited solid angle. In many cases this will be the only way to proceed, and then high luminosity has a different significance. The total rate in the restricted acceptance is less likely to be a problem, while the need for high luminosity to obtain sufficient data is obvious. Eight such experiments from studies carried out in the community are surveyed. Such experiments could be run on their own or in combination with others at the same intersection, or even with a large solid angle detector, if a window can be provided in the larger facility. The small solid angle detector would provide the trigger and special information, while the facility would provide back-up information on the rest of the event. We consider some possibilities of refurbishing existing detectors for use at CBA. This discussion is motivated by the fact that there is a growing number of powerful detectors at colliding beam machines around the world. Their builders have invested considerable amounts of time, money and ingenuity in them, and may wish to extend the useful lives of their creations, as new opportunities arise

Accelerator physics and technology challenges of very high energy hadron colliders

Science.gov (United States)

Shiltsev, Vladimir D.

2015-08-01

High energy hadron colliders have been in the forefront of particle physics for more than three decades. At present, international particle physics community considers several options for a 100 TeV proton-proton collider as a possible post-LHC energy frontier facility. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This paper briefly reviews the accelerator physics and technology challenges of the future very high energy colliders and outlines the areas of required research and development towards their technical and financial feasibility.

SimTrack: A compact c++ library for particle orbit and spin tracking in accelerators

Energy Technology Data Exchange (ETDEWEB)

Luo, Yun [Brookhaven National Laboratory (BNL), Upton, NY (United States)

2015-06-24

SimTrack is a compact c++ library of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam-beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam-beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam-beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

Colliding pulse injection experiments in non-collinear geometry for controlled laser plasma wakefield acceleration of electrons

International Nuclear Information System (INIS)

Toth, Carl B.; Esarey, Eric H.; Geddes, Cameron G.R.; Leemans, Wim P.; Nakamura, Kei; Panasenko, Dmitriy; Schroeder, Carl B.; Bruhwiler, D.; Cary, J.R.

2007-01-01

An optical injection scheme for a laser-plasma based accelerator which employs a non-collinear counter-propagating laser beam to push background electrons in the focusing and acceleration phase via ponderomotive beat with the trailing part of the wakefield driver pulse is discussed. Preliminary experiments were performed using a drive beam of a 0 = 2.6 and colliding beam of a 1 = 0.8 both focused on the middle of a 200 mu m slit jet backed with 20 bar, which provided ∼ 260 mu m long gas plume. The enhancement in the total charge by the colliding pulse was observed with sharp dependence on the delay time of the colliding beam. Enhancement of the neutron yield was also measured, which suggests a generation of electrons above 10 MeV

Accelerator-based atomic physics experiments with photon and ion beams

International Nuclear Information System (INIS)

Johnson, B.M.; Jones, K.W.; Meron, M.

1984-01-01

Accelerator-based atomic physics experiments at Brookhaven presently use heavy-ion beams from the Dual MP Tandem Van de Graaff Accelerator Facility for atomic physics experiments of several types. Work is presently in progress to develop experiments which will use the intense photon beams which will be available in the near future from the ultraviolet (uv) and x-ray rings of the National Synchrotron Light Source (NSLS). Plans are described for experiments at the NSLS and an exciting development in instrumentation for heavy-ion experiments is summarized

Relativistic-klystron two-beam-accelerator as a power source for a 1 TeV next linear collider: A systems study

International Nuclear Information System (INIS)

Yu, S.; Goffeney, N.; Deadrick, F.

1994-10-01

A physics, engineering, and costing study has been conducted to explore the feasibility of a relativistic-klystron two-beam-accelerator system as a power source candidate for a 1 TeV linear collider. We present a point design example which has acceptable transverse and longitudinal beam stability properties. Preliminary ''bottom-up'' cost estimate yields the full power source system at less than 1 billion dollars. The overall efficiency for rf production is estimated to be 36%

How It's Made - Polarized Proton Beam (444th Brookhaven Lecture)

International Nuclear Information System (INIS)

Zelenski, Anatoli

2008-01-01

Experiments with polarized beams at RHIC will provide fundamental tests of QCD, and the electro-weak interaction reveal the spin structure of the proton. Polarization asymmetries and parity violation are the strong signatures for identification of the fundamental processes, which are otherwise inaccessible. Such experiments require the maximum available luminosity and therefore polarization must be obtained as an extra beam quality without sacrificing intensity. There are proposals to polarize the high-energy proton beam in the storage rings by the Stern-Gerlach effect or spin-filter techniques. But so far, the only practically available option is acceleration of the polarized beam produced in the source and taking care of polarization survival during acceleration and storage. Two major innovations -- the 'Siberian Snake' technique for polarization preservation during acceleration and high current polarized proton sources make spin physics with the high-energy polarized beams feasible. The RHIC is the first high-energy collider, where the 'Siberian Snake' technique allowed of polarized proton beam acceleration up-to 250 GeV energy. The RHIC unique Optically Pumped Polarized Ion Source produces sufficient polarized beam intensity for complete saturation of the RHIC acceptance. This polarization technique is based on spin-transfer collisions between a proton or atomic hydrogen beam of a few keV beam energy and optically pumped alkali metal vapors. From the first proposal and feasibility studies to the operational source this development can be considered as example of successful unification of individual scientists ingenuity, international collaboration and modern technology application for creation of a new polarization technique, which allowed of two-to-three order of magnitude polarized beam intensity increase sufficient for loading the RHIC to its full capacity for polarization studies.

The e+, e- background at Relativistic Heavy Ion Collider (RHIC) generated by beam crossing

International Nuclear Information System (INIS)

Rhoades-Brown, M.J.; Ludlam, T.; Wu, J.; Bottcher, C.; Strayer, M.

1990-01-01

At the Brookhaven Relativistic Heavy Ion Collider (RHIC), fully stripped heavy ions will circulate in each of two rings up to beam energies of 250 (Z/A) GeV/u. During the beam crossing, the peripheral electromagnetic interaction between the heavy ions is sufficient to induce copious production of di-lepton pairs. These pairs are a potential source of background for the detectors at RHIC. In this paper we discuss the expected number of e + ,e - pairs, given the accepted initial luminosity value L of the collider. More importantly, we also calculate the differential cross sections for the angle, energy, rapidity and momentum distribution of the leptons. Using the luminosity L of the collider, these differential cross sections are normalized to the expected number of leptons per second. We restrict ourselves to e + ,e - production, a discussion of μ + ,μ - and τ + τ - distributions will be published later. The results are presented for the expected worst case, namely 197 Au 79+ ions at a beam kinetic energy of 100 GeV/u. This is forseen to be the heaviest ion for high luminosity experiments at RHIC. We note for a given energy, the cross section for e + ,e - production scales as Z 4 , where Z is the atomic number of the ions

Scientists at Brookhaven contribute to the development of a better electron accelerator

CERN Multimedia

2004-01-01

Scientists working at Brookhaven have developed a compact linear accelerator called STELLA (Staged Electron Laser Acceleration). Highly efficient, it may help electron accelerators become practical tools for applications in industry and medicine, such as radiation therapy (1 page)

RF properties of periodic accelerating structures for linear colliders

International Nuclear Information System (INIS)

Wang, J.W.

1989-07-01

With the advent of the SLAC electron-positron linear collider (SLC) in the 100 GeV center-of-mass energy range, research and development work on even higher energy machines of this type has started in several laboratories in the United States, Europe, the Soviet Union and Japan. These linear colliders appear to provide the only promising approach to studying e + e - physics at center-of-mass energies approaching 1 TeV. This thesis concerns itself with the study of radio frequency properties of periodic accelerating structures for linear colliders and their interaction with bunched beams. The topics that have been investigated are: experimental measurements of the energy loss of single bunches to longitudinal modes in two types of structures, using an equivalent signal on a coaxial wire to simulate the beam; a method of canceling the energy spread created within a single bunch by longitudinal wakefields, through appropriate shaping of the longitudinal charge distribution of the bunch; derivation of the complete transient beam-loading equation for a train of bunches passing through a constant-gradient accelerator section, with application to the calculation and minimization of multi-bunch energy spread; detailed study of field emission and radio frequency breakdown in disk-loaded structures at S-, C- and X-band frequencies under extremely high-gradient conditions, with special attention to thermal effects, radiation, sparking, emission of gases, surface damage through explosive emission and its possible control through RF-gas processing. 53 refs., 49 figs., 9 tabs

Bending magnets for the CBA beam-transport line

International Nuclear Information System (INIS)

Thern, R.E.

1983-01-01

The beam-transport line from the AGS to CBA requires 68 large bending magnets, consisting of pure dipoles and two types of combined function gradient magnets. All three types were designed with magnetic-field calculation program POISSON, using the same exterior dimensions and coil package. The design goal of +-1% momentum acceptance for the transport line required a wide horizontal aperture, with a much-smaller vertical aperture for economy. Two prototypes of one gradient magnet were built, and a facility constructed to measure them and the later production magnets. Measurements were done using both a long coil and a point coil (Rawson-Lush gaussmeter). Preliminary results show δB/B - 3 , δG/G - 2 , and δB 2 /B - 4 cm - 2 over the beam aperture. Due to end effects, the actual gradient differs from the design gradient by 1%, which has been compensated for in the beam-line design

Effect of 3D Polarization profiles on polarization measurements and colliding beam experiments

Energy Technology Data Exchange (ETDEWEB)

Fischer, W.; Bazilevsky, A.

2011-08-18

The development of polarization profiles are the primary reason for the loss of average polarization. Polarization profiles have been parametrized with a Gaussian distribution. We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the figure of merit in single and double spin experiments. Examples from RHIC are provided. The Relativistic Heavy Ion Collider (RHIC) is the only collider of spin polarized protons. During beam acceleration and storage profiles of the polarization P develop, which affect the polarization measured in a polarimeter, and the polarization and figure of merit (FOM) in colliding beam experiments. We calculate these for profiles in all dimensions, and give examples for RHIC. Like in RHIC we call the two colliding beams Blue and Yellow. We use the overbar to designate intensity-weighted averages in polarimeters (e.g. {bar P}), and angle brackets to designate luminosity-weighted averages in colliding beam experiments (e.g.

).

Effect of 3D Polarization profiles on polarization measurements and colliding beam experiments

International Nuclear Information System (INIS)

Fischer, W.; Bazilevsky, A.

2011-01-01

The development of polarization profiles are the primary reason for the loss of average polarization. Polarization profiles have been parametrized with a Gaussian distribution. We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the figure of merit in single and double spin experiments. Examples from RHIC are provided. The Relativistic Heavy Ion Collider (RHIC) is the only collider of spin polarized protons. During beam acceleration and storage profiles of the polarization P develop, which affect the polarization measured in a polarimeter, and the polarization and figure of merit (FOM) in colliding beam experiments. We calculate these for profiles in all dimensions, and give examples for RHIC. Like in RHIC we call the two colliding beams Blue and Yellow. We use the overbar to designate intensity-weighted averages in polarimeters (e.g. (bar P)), and angle brackets to designate luminosity-weighted averages in colliding beam experiments (e.g. ).

Overview of colliding beam facilities

International Nuclear Information System (INIS)

Herrera, J.C.; Month, M.

1979-01-01

A review is presented of the colliding beam facilities in existence today. The major high energy physics facilities around the world are described, and a view is presented of the beam collisions in which the instruments used to make the beams collide and those used to detect the products of particle interactions in the beam overlap region are described

Beam dynamics in the final focus section of the future linear collider

CERN Document Server

AUTHOR|(SzGeCERN)739431; TOMAS, Rogelio

The exploration of new physics in the ``Tera electron-Volt''~(TeV) scale with precision measurements requires lepton colliders providing high luminosities to obtain enough statistics for the particle interaction analysis. In order to achieve design luminosity values, linear colliders feature nanometer beam spot sizes at the Interaction~Point~(IP).\\par In addition to several effects affecting the luminosity, three main issues to achieve the beam size demagnification in the Final Focus Section (FFS) of the accelerator are the chromaticity correction, the synchrotron radiation effects and the correction of the lattice errors.\\par This thesis considers two important aspects for linear colliders: push the limits of linear colliders design, in particular the chromaticity correction and the radiation effects at 3~TeV, and the instrumentation and experimental work on beam stabilization in a test facility.\\par The current linear collider projects, CLIC~\\cite{CLICdes} and ILC~\\cite{ILCdes}, have lattices designed using...

Selected topics in particle accelerators: Proceedings of the CAP meetings. Volume 5

International Nuclear Information System (INIS)

Parsa, Z.

1995-01-01

This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory Editing and changes to the authors' contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on nine presentations: ''The Energy Exchange and Efficiency Consideration in Klystrons'', ''Some Properties of Microwave RF Sources for Future Colliders + Overview of Microwave Generation Activity at the University of Maryland'', ''Field Quality Improvements in Superconducting Magnets for RHIC'', ''Hadronic B-Physics'', ''Spiking Pulses from Free Electron Lasers: Observations and Computational Models'', ''Crystalline Beams in Circular Accelerators'', ''Accumulator Ring for AGS ampersand Recent AGS Performance'', ''RHIC Project Machine Status'', and ''Gamma-Gamma Colliders.''

Selected topics in particle accelerators: Proceedings of the CAP meetings. Volume 3

International Nuclear Information System (INIS)

Parsa, Z.

1995-01-01

This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory. Editing and changes to authors' contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on eight presentations: ''Inverse Cherenkov Laser Acceleration of Electron Beams'', ''High Brightness Field Emission Cathodes'', ''QCD/Teraflop Collaboration: The Future of Supercomputing'', ''Report on Dipole R ampersand D'', ''Reaching Maximum Luminosity in Hadron Colliders at 10-100 TeV'', ''STAR Collaboration Project Status Report: Quarks and Gluons'', ''PHENIX Collaboration Project Status Report'', and ''Update on Status of BNL Relativistic Heavy Ion Collider (RHIC) Project: RHIC Design Issues.''

General formulae of luminosity for various types of colliding beam machines

International Nuclear Information System (INIS)

Suzuki, Toshio.

1976-07-01

Summarized are the formulae of luminosity for proton-proton, electron-positron and electron-proton colliding beam machines. Both coasting and bunched proton beams are considered. The expressions are derived from the first principle. These formulae will be useful for the design of an intersecting storage accelerator such as TRISTAN. (auth.)

Beam emittance and the effects of the rf, space charge and wake fields: Application to the ATF photoelectron beam

International Nuclear Information System (INIS)

Parsa, Z.

1991-01-01

Laser driven photoelectron guns are of interest for use in new methods of accelerations, future development of Linear Colliders and new experiments such as Free Electron laser (IFEL). Such guns are potential source of low emittance-high current and short bunch length electron beams, where the emitted electrons are accelerated quickly to a relativistic energy by a strong rf, electric field in the cavity. We present a brief overview of the beam dynamic studies, e.g. emittance for the Brookhaven National Laboratory (BNL) ATF high brightness photocathode radio frequency gun (now in operation), and show the effects of the rf, Space Charge, and Wake fields on the photoelectrons. 4 refs., 7 figs

ICFA Beam Dynamics Newsletter

Energy Technology Data Exchange (ETDEWEB)

Ben-Zvi I.; Kuczewski A.; Altinbas, Z.; Beavis, D.; Belomestnykh,; Dai, J. et al

2012-07-01

The Collider-Accelerator Department at Brookhaven National Laboratory is building a high-brightness 500 mA capable Energy Recovery Linac (ERL) as one of its main R&D thrusts towards eRHIC, the polarized electron - hadron collider as an upgrade of the operating RHIC facility. The ERL is in final assembly stages, with injection commisioning starting in October 2012. The objective of this ERL is to serve as a platform for R&D into high current ERL, in particular issues of halo generation and control, Higher-Order Mode (HOM) issues, coherent emissions for the beam and high-brightness, high-power beam generation and preservation. The R&D ERL features a superconducting laser-photocathode RF gun with a high quantum efficiency photoccathode served with a load-lock cathode delivery system, a highly damped 5-cell accelerating cavity, a highly flexible single-pass loop and a comprehensive system of beam instrumentation. In this ICFA Beam Dynamics Newsletter article we will describe the ERL in a degree of detail that is not usually found in regular publications. We will discuss the various systems of the ERL, following the electrons from the photocathode to the beam dump, cover the control system, machine protection etc and summarize with the status of the ERL systems.

SimTrack: A compact c++ code for particle orbit and spin tracking in accelerators

Energy Technology Data Exchange (ETDEWEB)

Luo, Yun

2015-11-21

SimTrack is a compact c++ code of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam–beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam–beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam–beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this paper, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

Two-beam accelerator

International Nuclear Information System (INIS)

Sessler, A.M.; Hopkins, D.B.

1986-06-01

The Two-Beam Accelerator (TBA) consists of a long high-gradient accelerator structure (HGS) adjacent to an equal-length Free Electron Laser (FEL). In the FEL, a beam propagates through a long series of undulators. At regular intervals, waveguides couple microwave power out of the FEL into the HGS. To replenish energy given up by the FEL beam to the microwave field, induction accelerator units are placed periodically along the length of the FEL. In this manner it is expected to achieve gradients of more than 250 MV/m and thus have a serious option for a 1 TeV x 1 TeV linear collider. The state of present theoretical understanding of the TBA is presented with particular emphasis upon operation of the ''steady-state'' FEL, phase and amplitude control of the rf wave, and suppression of sideband instabilities. Experimental work has focused upon the development of a suitable HGS and the testing of this structure using the Electron Laser Facility (ELF). Description is given of a first test at ELF with a seven-cell 2π/3 mode structure which without preconditioning and with a not-very-good vacuum nevertheless at 35 GHz yielded an average accelerating gradient of 180 MV/m

The High Flux Beam Reactor at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Shapiro, S.M.

1994-01-01

Brookhaven National Laboratory's High Flux Beam Reactor (HFBR) was built because of the need of the scientist to always want 'more'. In the mid-50's the Brookhaven Graphite reactor was churning away producing a number of new results when the current generation of scientists, led by Donald Hughes, realized the need for a high flux reactor and started down the political, scientific and engineering path that led to the BFBR. The effort was joined by a number of engineers and scientists among them, Chemick, Hastings, Kouts, and Hendrie, who came up with the novel design of the HFBR. The two innovative features that have been incorporated in nearly all other research reactors built since are: (i) an under moderated core arrangement which enables the thermal flux to peak outside the core region where beam tubes can be placed, and (ii) beam tubes that are tangential to the core which decrease the fast neutron background without affecting the thermal beam intensity. Construction began in the fall of 1961 and four years later, at a cost of $12 Million, criticality was achieved on Halloween Night, 1965. Thus began 30 years of scientific accomplishments

W,Z0 production at the pp collider

International Nuclear Information System (INIS)

Bunce, G.; Gordon, H.A.; Killian, T.J.

1982-01-01

We have examined some experimental questions relating to the production of W's and Z 0 's at a pp collider. To be specific we have considered a Colliding Beam Accelerator (CBA) with center of energy √s = 800 GeV and luminosity L = 10 33 cm -2 sec -1 (the standard BNL Isabelle (ISA) operating conditions). Most experiments should accumulate 10 sec of beam and therefore will have an integrated luminosity L = 10 40 cm -2 . This corresponds to the production of millions of conventional charged W's per interaction region and gives the potential for high statistics studies of the properties of W's and for experiments searching for higher mass objects. Our focus has been on testing predictions of the standard model. We have concentrated on W production since it is likely the standard Z 0 will be observed in the near future. In most cases the W is detected via its semileptonic decay W → l + nu. The specific topics considered are: W +- production: pp → W +- + X, W +- → e +- + nu, pp → W +- + γ + X, polarization effects in W +- production, and very high luminosity experiments

Beam Loss Calibration Studies for High Energy Proton Accelerators

CERN Document Server

Stockner, M

2007-01-01

CERN's Large Hadron Collider (LHC) is a proton collider with injection energy of 450 GeV and collision energy of 7 TeV. Superconducting magnets keep the particles circulating in two counter rotating beams, which cross each other at the Interaction Points (IP). Those complex magnets have been designed to contain both beams in one yoke within a cryostat. An unprecedented amount of energy will be stored in the circulating beams and in the magnet system. The LHC outperforms other existing accelerators in its maximum beam energy by a factor of 7 and in its beam intensity by a factor of 23. Even a loss of a small fraction of the beam particles may cause the transition from the superconducting to the normal conducting state of the coil or cause physical damage to machine components. The unique combination of these extreme beam parameters and the highly advanced superconducting technology has the consequence that the LHC needs a more efficient beam cleaning and beam loss measurement system than previous accelerators....

Beam-beam limit in e+e- circular colliders

International Nuclear Information System (INIS)

Ohmi, K.; Tawada, M.; Kamada, S.; Oide, K.; Cai, Y.; Qiang, J.

2004-01-01

Beam-beam effects limit the luminosity of circular colliders. Once the bunch population exceeds a threshold, the luminosity increases at a slower rate. This phenomenon is called the beam-beam limit. Onset of the beam-beam limit has been analyzed with various simulation methods based on the weak-strong and strong-strong models. We have observed that an incoherent phenomenon is mainly concerned in the beam-beam limit. The simulation have shown that equilibrium distributions of the two colliding beams are distorted from Gaussians when the luminosity is limited. The beam-beam limit is estimated to be ξ∼0.1 for a B factory with damping time of several thousand turns

Test accelerator for linear collider

International Nuclear Information System (INIS)

Takeda, S.; Akai, K.; Akemoto, M.; Araki, S.; Hayano, H.; Hugo, T.; Ishihara, N.; Kawamoto, T.; Kimura, Y.; Kobayashi, H.; Kubo, T.; Kurokawa, S.; Matsumoto, H.; Mizuno, H.; Odagiri, J.; Otake, Y.; Sakai, H.; Shidara, T.; Shintake, T.; Suetake, M.; Takashima, T.; Takata, K.; Takeuchi, Y.; Urakawa, J.; Yamamoto, N.; Yokoya, K.; Yoshida, M.; Yoshioka, M.; Yamaoka, Y.

1989-01-01

KEK has proposed to build Test Accelerator Facility (TAF) capable of producing a 2.5 GeV electron beam for the purpose of stimulating R ampersand D for linear collider in TeV region. The TAF consists of a 1.5 GeV S-band linear accelerator, 1.5 GeV damping ring and 1.0 GeV X-band linear accelerator. The TAF project will be carried forward in three phases. Through Phase-I and Phase-II, the S-band and X-band linacs will be constructed, and in Phase-III, the damping ring will be completed. The construction of TAF Phase-I has started, and the 0.2 GeV S-band injector linac has been almost completed. The Phase-I linac is composed of a 240 keV electron gun, subharmonic bunchers, prebunchers and traveling buncher followed by high-gradient accelerating structures. The SLAC 5045 klystrons are driven at 450 kV in order to obtain the rf-power of 100 MW in a 1 μs pulse duration. The rf-power from a pair of klystrons are combined into an accelerating structure. The accelerating gradient up to 100 MeV/m will be obtained in a 0.6 m long structure. 5 refs., 3 figs., 2 tabs

Internal trim coils for CBA superconducting magnets

International Nuclear Information System (INIS)

Thompson, P.A.; Aronson, S.; Cottingham, J.G.; Garber, M.; Hahn, H.; Sampson, W.B.

1983-01-01

In order to correct iron saturation effects and shape the beam working line, superconducting trim coils have been constructed, which operate inside the main coils. Detailed studies of mechanical properties, quench behavior, fields produced, and hysteresis have lead to the production of accelerator-quality coils generating the required-strength harmonics up to cos (7theta). These are routinely installed in CBA main magnets and operate at 80% of short sample with negligible training in an ambient field of more than 5.3T

Ion Sources, Preinjectors and the Road to EBIS (459th Brookhaven Lecture)

International Nuclear Information System (INIS)

Alessi, James

2010-01-01

To meet the requirements of the scientific programs of the Relativistic Heavy Ion Collider and the NASA Space Radiation Lab, BNL's Collider-Accelerator Department needs a variety of ion sources. Although these sources are a relatively small and inexpensive part of an accelerator, they can have a big impact on the machine's overall performance. For the 459th Brookhaven Lecture, James Alessi will describe C-AD's long history of developing state-of-the-art ion sources for its accelerators, and its current process for source and pre-injector development. He will follow up with a discussion of the features and development status of EBIS, which, as the newest source and preinjector, is in the final stages of commissioning at the end of a five-year construction project.

Design study of primary ion provider for relativistic heavy ion collider electron beam ion source.

Science.gov (United States)

Kondo, K; Kanesue, T; Tamura, J; Okamura, M

2010-02-01

Brookhaven National Laboratory has developed the new preinjector system, electron beam ion source (EBIS) for relativistic heavy ion collider (RHIC) and National Aeronautics and Space Administration Space Radiation Laboratory. Design of primary ion provider is an essential problem since it is required to supply beams with different ion species to multiple users simultaneously. The laser ion source with a defocused laser can provide a low charge state and low emittance ion beam, and is a candidate for the primary ion source for RHIC-EBIS. We show a suitable design with appropriate drift length and solenoid, which helps to keep sufficient total charge number with longer pulse length. The whole design of primary ion source, as well as optics arrangement, solid targets configuration and heating about target, is presented.

Colliders

CERN Document Server

Chou, Weiren

2014-01-01

The idea of colliding two particle beams to fully exploit the energy of accelerated particles was first proposed by Rolf Wideröe, who in 1943 applied for a patent on the collider concept and was awarded the patent in 1953. The first three colliders — AdA in Italy, CBX in the US, and VEP-1 in the then Soviet Union — came to operation about 50 years ago in the mid-1960s. A number of other colliders followed. Over the past decades, colliders defined the energy frontier in particle physics. Different types of colliers — proton–proton, proton–antiproton, electron–positron, electron–proton, electron-ion and ion-ion colliders — have played complementary roles in fully mapping out the constituents and forces in the Standard Model (SM). We are now at a point where all predicted SM constituents of matter and forces have been found, and all the latest ones were found at colliders. Colliders also play a critical role in advancing beam physics, accelerator research and technology development. It is timel...

Bending magnets for the CBA beam-transport line

Energy Technology Data Exchange (ETDEWEB)

Thern, R.E.

1983-01-01

The beam-transport line from the AGS to CBA requires 68 large bending magnets, consisting of pure dipoles and two types of combined function gradient magnets. All three types were designed with magnetic-field calculation program POISSON, using the same exterior dimensions and coil package. The design goal of +-1% momentum acceptance for the transport line required a wide horizontal aperture, with a much-smaller vertical aperture for economy. Two prototypes of one gradient magnet were built, and a facility constructed to measure them and the later production magnets. Measurements were done using both a long coil and a point coil (Rawson-Lush gaussmeter). Preliminary results show ..delta..B/B < 0.2 x 10/sup -3/, ..delta..G/G < 0.3 x 10/sup -2/, and ..delta..B/sub 2//B < 0.3 x 10/sup -4/ cm/sup -2/ over the beam aperture. Due to end effects, the actual gradient differs from the design gradient by 1%, which has been compensated for in the beam-line design.

Beam-beam issues in asymmetric colliders

International Nuclear Information System (INIS)

Furman, M.A.

1992-07-01

We discuss generic beam-beam issues for proposed asymmetric e + - e - colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II)

Pulsed RF Sources for Linear Colliders

International Nuclear Information System (INIS)

Fernow, R.C.

1995-01-01

These proceedings represent papers presented at the workshop on pulsed RF sources for linear colliders. The workshop examined the performance of RF sources for possible future linear colliders. Important sources were presented on new type of klystrons, gyrotrons and gyroklystrons. A number of auxiliary topics were covered, including modulators, pulse compression, power extraction, windows, electron guns and gun codes. The workshop was sponsored by the International Committee for Future Accelerators(ICFA), the U.S. Department of Energy and the Center for Accelerator Physics at Brookhaven National Laboratory. There were forty one papers presented at the workshop and all forty one have been abstracted for the Energy Science and Technology database

Summary Report of Working Group 5: Electron Beam Driven Plasma Accelerators

International Nuclear Information System (INIS)

Hogan, Mark J.; Conde, Manoel E.

2009-01-01

Electron beam driven plasma accelerators have seen rapid progress over the last decade. Recent efforts have built on this success by constructing a concept for a plasma wakefield accelerator based linear collider. The needs for any future collider to deliver both energy and luminosity have substantial implications for interpreting current experiments and setting priorities for the future. This working group reviewed current experiments and ideas in the context of the demands of a future collider. The many discussions and presentations are summarized here.

The Relativistic Heavy Ion Collider (RHIC) cryogenic system at Brookhaven National Laboratory: Review of the modifications and upgrades since 2002 and planned improvements

International Nuclear Information System (INIS)

Than, R.; Tuozzolo, Joseph; Sidi-Yekhlef, Ahmed; Ganni, Venkatarao; Knudsen, Peter; Arenius, Dana

2008-01-01

Brookhaven National Laboratory continues its multi-year program to improve the operational efficiency, reliability, and stability of the cryogenic system, which also resulted in an improved beam availability of the Relativistic Heavy Ion Collider (RHIC). This paper summarizes the work and changes made after each phase over the past four years to the present, as well as proposed future improvements. Power usage dropped from an initial 9.4 MW to the present 5.1 MW and is expected to drop below 5 MW after the completion of the remaining proposed improvements. The work proceeded in phases, balancing the Collider's schedule of operation, time required for the modifications and budget constraints. The main changes include process control, compressor oil removal and management, elimination of the use of cold compressors and two liquid-helium storage tanks, insulation of the third liquid-helium storage tank, compressor-bypass flow reduction and the addition of a load turbine (Joule-Thomson)

Heavy ion acceleration strategies in the AGS accelerator complex -- 1994 Status report

International Nuclear Information System (INIS)

Ahrens, L.A.; Benjamin, J.; Blaskiewicz, M.

1995-01-01

The strategies invoked to satisfy the injected beam specifications for the Brookhaven Relativistic Heavy Ion Collider (RHIC) continue to evolve, in the context of the yearly AGS fixed target heavy ion physics runs. The primary challenge is simply producing the required intensity. The acceleration flexibility available particularly in the Booster main magnet power supply and rf accelerating systems, together with variations in the charge state delivered from the Tandem van de Graaff, and accommodation by the AGS main magnet and rf systems allow the possibility for a wide range of options. The yearly physics run provides the opportunity for exploration of these options with the resulting significant evolution in the acceleration plan. This was particularly true in 1994 with strategies involving three different charge states and low and high acceleration rates employed in the Booster. The present status of this work will be presented

Final environmental impact statement. Proton--Proton Storage Accelerator Facility (ISABELLE), Brookhaven National Laboratory, Upton, New York

International Nuclear Information System (INIS)

1978-08-01

An Environmental Impact Statement for a proposed research facility (ISABELLE) to be built at Brookhaven National Laboratory (BNL) is presented. It was prepared by the Department of Energy (DOE) following guidelines issued for such analyses. In keeping with DOE policy, this statement presents a concise and issues-oriented analysis of the significant environmental effects associated with the proposed action. ISABELLE is a proposed physics research facility where beams of protons collide providing opportunities to study high energy interactions. The facility would provide two interlaced storage ring proton accelerators, each with an energy up to 400 GeV intersecting in six experimental areas. The rings are contained in a tunnel with a circumference of 3.8 km (2.3 mi). The facility will occupy 250 ha (625 acres) in the NW corner of the existing BNL site. A draft Environmental Impact Statement for this proposed facility was issued for public review and comment by DOE on February 21, 1978. The principal areas of concern expressed were in the areas of radiological impacts and preservation of cultural values. After consideration of these comments, appropriate actions were taken and the text of the statement has been amended to reflect the comments. The text was annotated to indicate the origin of the comment. The Appendices contain a glossary of terms and listings of metric prefixes and conversions and symbols and abbreviations

A Concept of Plasma Wake Field Acceleration Linear Collider (PWFA-LC)

International Nuclear Information System (INIS)

Seryi, Andrei; Hogan, Mark; Pei, Shilun; Raubenheimer, Tor; Tenenbaum, Peter; Katsouleas, Tom; Huang, Chengkun; Joshi, Chan; Mori, Warren; Muggli, Patric

2009-01-01

Plasma Wake-Field Acceleration (PWFA) has demonstrated acceleration gradients above 50 GeV/m. Simulations have shown drive/witness bunch configurations that yield small energy spreads in the accelerated witness bunch and high energy transfer efficiency from the drive bunch to the witness bunch, ranging from 30% for a Gaussian drive bunch to 95% for a shaped longitudinal profile. These results open the opportunity for a linear collider that could be compact, efficient and more cost effective that the present microwave technologies. A concept of a PWFA-based Linear Collider (PWFA-LC) has been developed and is described in this paper. The drive beam generation and distribution, requirements on the plasma cells, and optimization of the interaction region parameters are described in detail. The R and D steps needed for further development of the concept are also outlined.

Physics potential of the CBA: a summary

International Nuclear Information System (INIS)

Baggett, N.; Gibbard, B.; Gordon, H.; Paige, F.; Trueman, T.L.

1983-01-01

The purpose of this summary is to bring to the attention of the high energy physics community the wide variety of new physics experiments that the high luminosity and high energy of CBA will make possible. These examples are intended to illustrate the power and flexibility of the machine. It will provide the facilities for a very large number of experimentalists to pursue a broad range of physics. The high luminosity allows not only the study of rare processes but also the use of small, special purpose detectors. The six interaction regions can be arranged in different configurations, so, for example, one can be at very high luminosity for a μ + μ - experiment, another can have a small diamond for use with a vertex detector, and so on. There is the possibility of polarized protons, heavy ions and variable energies in the two rings. The machine will be dedicated solely to colliding beam physics. There is a great deal of very important physics that will clearly be done if CBA is built: detailed studies of the W and its interactions, extensive studies of the properties of the b-quark, systematic studies of QCD and proton structure through the Drell-Yan and high p/sub T/ processes, new flavor searches in a significant mass range. In the more speculative area, supersymmetry, technicolor, composite models and alternatives to the standard electroweak theory have been considered, not so much as tests of these theories as tests of the capabilities of the machine. These examples should demonstrate the power of the CBA to probe deeply into nature's secrets and to move nearer an understanding of the fundamental theory, whatever it may be. The CBA would provide the world's high energy physics community with a unique and valuable resource

BROOKHAVEN: Getting a boost

International Nuclear Information System (INIS)

Anon.

1992-01-01

Some recent scenarios for the future of US high energy physics have glossed over the ongoing high energy physics role of Brookhaven's Alternating Gradient Synchrotron (AGS), seeing it being relegated essentially to a service function as the injector for the RHIC heavy ion collider. However this view is not shared by Brookhaven, now enjoying the benefits of a Booster to inject into the AGS

Technical Challenges and Scientific Payoffs of Muon BeamAccelerators for Particle Physics

Energy Technology Data Exchange (ETDEWEB)

Zisman, Michael S.

2007-09-25

Historically, progress in particle physics has largely beendetermined by development of more capable particle accelerators. Thistrend continues today with the recent advent of high-luminosityelectron-positron colliders at KEK and SLAC operating as "B factories,"the imminent commissioning of the Large Hadron Collider at CERN, and theworldwide development effort toward the International Linear Collider.Looking to the future, one of the most promising approaches is thedevelopment of muon-beam accelerators. Such machines have very highscientific potential, and would substantially advance thestate-of-the-art in accelerator design. A 20-50 GeV muon storage ringcould serve as a copious source of well-characterized electron neutrinosor antineutrinos (a Neutrino Factory), providing beams aimed at detectorslocated 3000-7500 km from the ring. Such long baseline experiments areexpected to be able to observe and characterize the phenomenon ofcharge-conjugation-parity (CP) violation in the lepton sector, and thusprovide an answer to one of the most fundamental questions in science,namely, why the matter-dominated universe in which we reside exists atall. By accelerating muons to even higher energies of several TeV, we canenvision a Muon Collider. In contrast with composite particles likeprotons, muons are point particles. This means that the full collisionenergy is available to create new particles. A Muon Collider has roughlyten times the energy reach of a proton collider at the same collisionenergy, and has a much smaller footprint. Indeed, an energy frontier MuonCollider could fit on the site of an existing laboratory, such asFermilab or BNL. The challenges of muon-beam accelerators are related tothe facts that i) muons are produced as a tertiary beam, with very large6D phase space, and ii) muons are unstable, with a lifetime at rest ofonly 2 microseconds. How these challenges are accommodated in theaccelerator design will be described. Both a Neutrino Factory and a MuonCollider

Colliding beam physics at Fermilab: interaction regions, beam storage, antiproton cooling, production, and colliding

Energy Technology Data Exchange (ETDEWEB)

Walker, J.K. (ed.)

1977-01-01

The purpose of the colliding beams experment department at Fermilab was to bring about collisions of the stored beams in the energy doubler/saver and main ring, and construct experimental areas with appropriate detectors. To explore the feasibility of using the main ring as a storage device, several studies were carried out to investigate beam growth, loss, and the backgrounds in detectors at possible intersection regions. This range of developments constituted the major topics at the 1977 Summer Study reported here. Emphasis in part one is on interaction regions, beam storage, antiproton cooling, production, and colliding. 40 papers from this part are included in the data base. (GHT)

Channeling acceleration: A path to ultrahigh energy colliders

International Nuclear Information System (INIS)

Chen, P.; Huang, Z.; Ruth, R.D.

1995-01-01

Acceleration of charged particles along crystal channels has been proposed earlier in an attempt to achieve high acceleration gradient while at the same time to suppress excessive emittance growth. Recently the authors demonstrated that a particle in a generic focusing channel can in principle absolutely damp to its transverse ground state without any quantum excitation. This yields the minimum beam emittance that one can ever attain, γε min = ℎ/2mc, limited only by the uncertainty principle. In this paper they discuss sources of excitation when a more realistic channel is considered, including bremsstrahlung and multiple Coulomb scattering. They investigate the possibility of colliding ultrahigh energy particles in such strong focusing channels without the need of a final focusing system, where the concept of luminosity departs from the conventional approach. They show that a high luminosity can be attained with a rather modest beam power

Proceedings of the 1979 workshop on beam current limitations in storage rings, July 16-27, 1979

International Nuclear Information System (INIS)

Pellegrini, C.

1979-01-01

The Workshop on Beam Current Limitations in Storage Rings was held at Brookhaven National Laboratory from July 16 to 27, 1979. The purpose of this Workshop was to discuss the physical mechanisms limiting the beam current or current density in accelerators or storage rings. Many of these machines are now being built or planned for a variety of applications, such as colliding beam experiments, synchrotron light production, heavy ion beams. This diversity was reflected in the Workshop and in the papers which have been contributed to these Proceedings. The twenty-one papers from the workshop were incorporated individually in the data base

Ion colliders

Energy Technology Data Exchange (ETDEWEB)

Fischer, W.

2011-12-01

Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

Ion colliders

International Nuclear Information System (INIS)

Fischer, W.

2010-01-01

Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions (77Asb1, 81Bou1). The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

Technical Challenges and Scientific Payoffs of Muon Beam Accelerators for Particle Physics

International Nuclear Information System (INIS)

Zisman, Michael S.

2007-01-01

Historically, progress in particle physics has largely been determined by development of more capable particle accelerators. This trend continues today with the recent advent of high-luminosity electron-positron colliders at KEK and SLAC operating as 'B factories', the imminent commissioning of the Large Hadron Collider at CERN, and the worldwide development effort toward the International Linear Collider. Looking to the future, one of the most promising approaches is the development of muon-beam accelerators. Such machines have very high scientific potential, and would substantially advance the state-of-the-art in accelerator design. A 20-50 GeV muon storage ring could serve as a copious source of well-characterized electron neutrinos or antineutrinos (a Neutrino Factory), providing beams aimed at detectors located 3000-7500 km from the ring. Such long baseline experiments are expected to be able to observe and characterize the phenomenon of charge-conjugation-parity (CP) violation in the lepton sector, and thus provide an answer to one of the most fundamental questions in science, namely, why the matter-dominated universe in which we reside exists at all. By accelerating muons to even higher energies of several TeV, we can envision a Muon Collider. In contrast with composite particles like protons, muons are point particles. This means that the full collision energy is available to create new particles. A Muon Collider has roughly ten times the energy reach of a proton collider at the same collision energy, and has a much smaller footprint. Indeed, an energy frontier Muon Collider could fit on the site of an existing laboratory, such as Fermilab or BNL. The challenges of muon-beam accelerators are related to the facts that (1) muons are produced as a tertiary beam, with very large 6D phase space, and (2) muons are unstable, with a lifetime at rest of only 2 microseconds. How these challenges are accommodated in the accelerator design will be described. Both a

High-quality electron beam generation in a proton-driven hollow plasma wakefield accelerator

Science.gov (United States)

Li, Y.; Xia, G.; Lotov, K. V.; Sosedkin, A. P.; Hanahoe, K.; Mete-Apsimon, O.

2017-10-01

Simulations of proton-driven plasma wakefield accelerators have demonstrated substantially higher accelerating gradients compared to conventional accelerators and the viability of accelerating electrons to the energy frontier in a single plasma stage. However, due to the strong intrinsic transverse fields varying both radially and in time, the witness beam quality is still far from suitable for practical application in future colliders. Here we demonstrate the efficient acceleration of electrons in proton-driven wakefields in a hollow plasma channel. In this regime, the witness bunch is positioned in the region with a strong accelerating field, free from plasma electrons and ions. We show that the electron beam carrying the charge of about 10% of 1 TeV proton driver charge can be accelerated to 0.6 TeV with a preserved normalized emittance in a single channel of 700 m. This high-quality and high-charge beam may pave the way for the development of future plasma-based energy frontier colliders.

Demonstration of two-beam acceleration in CTF II

CERN Document Server

Bossart, Rudolf; Carron, G; Chanudet, M; Chautard, F; Delahaye, J P; Godot, J C; Hutchins, S; Kamber, I; Martínez, C; Suberlucq, Guy; Tenenbaum, P G; Thorndahl, L; Valentini, M; Wilson, Ian H; Wuensch, Walter

1999-01-01

The second phase of the Compact LInear Collider (CLIC) Test Facility (CTF II) at CERN has demon-strated the feasibility of two-beam acceleration at 30 GHz using a high-charge drive beam, running paral lel to the main beam, as the RF power source. To date accelerating gradients of 59 MV/m at 30 GHz have been achieved. In CTF II, the two beams are generated by 3 GHz RF photo-injectors and are acceler ated in 3 GHz linacs, before injection into the 30 GHz modules. The drive beam linac has to accelerate a 16 ns long train of 48 bunches, each with a nominal charge of 13.4 nC. To cope with the very su bstantial beam-loading special accelerating structures are used (running slightly off the bunch repetition frequency). A magnetic chicane compresses the bunches to less than 5 ps fwhm, this is needed for efficient 30 GHz power generation. The 30 GHz modules are fully-engineered representative sections of CLIC, they include a 30 GHz decelerator for the drive beam, a 30 GHz accelerator for the main beam, high resolution...

Beam-strahlung effects in e-p collider

International Nuclear Information System (INIS)

Cho, Y.

1982-09-01

The electromagnetic fields produced by one beam in an interaction point of a colliding-beam facility cause to the emission of synchrotron radiation by the other beam. This effect, the beam strahlung, for the e+e - colliders has been considered by several authors, and they have pointed out that the effect is very important consideration at very-high-energy e+e - colliders. At the first glance, the beam-strahlung effect can play an important role in the e-p collision due to the fact that the circulating currents in the collider are much higher than those of the e+e - machine. However the detailed study shows that is not the case because of the collision geometry involved. What follows in this note is the beam-strahlung derivations using the method previously used by Hofmann and Keil. The difference between this note and that of Hofman and Keil is that in the case of e+e - collider, equal mass particles are involved in the consideration and, in the e-p case, the electrons radiate and the protons provide the electromagnetic fields

Studies of polarized beam acceleration and Siberian Snakes

International Nuclear Information System (INIS)

Lee, S.Y.

1992-01-01

We studied depolarization mechanisms of polarized proton acceleration in high energy accelerators with snakes and found that the perturbed spin tune due to the imperfection resonance plays an important role in beam depolarization at snake resonances. We also found that even order snake resonances exist in the overlapping intrinsic and imperfection resonances. Due to the perturbed spin tune of imperfection resonances, each snake resonance splits into two. Thus the available betatron tune space becomes smaller. Some constraints on polarized beam colliders were also examined

Expected damage to accelerator equipment due to the impact of the full LHC beam: beam instrumentation, experiments and simulations

CERN Document Server

Burkart, Florian

The Large Hadron Collider (LHC) is the biggest and most powerful particle accelerator in the world, designed to collide two proton beams with particle momentum of 7 TeV/c each. The stored energy of 362MJ in each beam is sufficient to melt 500 kg of copper or to evaporate about 300 liter of water. An accidental release of even a small fraction of the beam energy can cause severe damage to accelerator equipment. Reliable machine protection systems are necessary to safely operate the accelerator complex. To design a machine protection system, it is essential to know the damage potential of the stored beam and the consequences in case of a failure. One (catastrophic) failure would be, if the entire beam is lost in the aperture due to a problem with the beam dumping system. This thesis presents the simulation studies, results of a benchmarking experiment, and detailed target investigation, for this failure case. In the experiment, solid copper cylinders were irradiated with the 440GeV proton beam delivered by the ...

'Diffraction-free' optical beams in inverse free electron laser accelerators

International Nuclear Information System (INIS)

Cai, S.Y.; Bhattacharjee, A.; Marshall, T.C.

1988-01-01

'Diffraction-free' optical beams correspond to exact solutions of the wave equation in free space with the remarkable property that they propagate with negligible transverse spreading for distances much larger than the Rayleigh range. The requirement for this to occur is a large aperture. Using a 2D computer code, we find that these optical beams will also propagate with negligible diffraction even when perturbed by the electron beam in an IFEL; indeed they match well the FEL requirement for the accelerator. The numerical simulations are performed for the proposed facility at Brookhaven in which λ s =10 μm, B=1.5 T (linearly tapered l w =1.31-6.28 cm) and the optical beam power is either 8x10 11 W or 2.3x10 10 W. Approximately 70% of the electrons constituting a beam of current 5 mA or 15 A, radius 0.14 mm and initial energy of 50 MeV is accelerated at 50 MeV/m. (orig.)

Transverse equilibria in linear collider beam-beam collisions

International Nuclear Information System (INIS)

Rosenzweig, J.B.; Chen, Pisin

1991-01-01

It has been observed in simulations of the beam-beam interaction in linear colliders that a near equilibrium pinched state of the colliding beams develops when the disruption parameter is large (D much-gt 1). In this state the beam transverse density distributions are peaked at center, with long tails. The authors present here an analytical model of the equilibrium approached by the beams, that of a generalized Bennett pinch which develops through collisionless damping due to the strong nonlinearity of the beam-beam interaction. In order to calculate the equilibrium pinched beam size, an estimation of the rms emittance growth is made which takes into account the partial adiabaticity of the collision. This pinched beam size is used to derive the luminosity enhancement factors whose scaling is in agreement with the simulation results for both D and thermal factor A = σ z /β * large, and explains the previously noted cubic relationship between round and flat beam enhancement factors

'TRISTAN'; a database for electron colliding beam experiments

International Nuclear Information System (INIS)

Shimizu, Y.; Igarashi, M.; Nakazawa, N.; Oyanagi, Y.

1982-01-01

In this data base, the reference papers on the experiments of positron-electron colliding beam were collected for the purpose to utilize them for the TRISTAN project. The on-line retrieval of the references is possible. The number of the references is 289 during the period from January, 1974, to September, 1981. The collection of data will be continued hereafter. The terms retrievable are accelerator, incident beam, code, and radiation correction formula. The SC (name of the first author, year), incident energy, detector, luminocity, integrated luminosity, reaction, purpose and comments are also included as the data. The system is written in FORTRAN 77, and is portable. (Kato, T.)

Production of high power microwaves for particle acceleration with an FEL bunched electron beam

CERN Document Server

Gardelle, J; Marchese, G; Padois, M; Rullier, J L; Donohue, J T

1999-01-01

Among the studies in the framework of high gradient linear electron-positron collider research, the Two-Beam Accelerator (TBA) is a very promising concept, and two projects are in progress, the Compact Linear Collider project at CERN (W. Schnell, Report no. CERN SL/92-51 and CLIC note 184; K. Huebner, CERN/PS 92-43, CLIC note 176; S. Van der Meer, CERN/PS 89-50, CLIC note 97.) and the Relativistic Klystron-TBA project at LBNL (Technical Review Committee, International Linear Collider Technical Review Committee Report 1995, SLAC-R-95-471, 1995). In a TBA an extremely intense low-energy electron beam, called the drive beam, is bunched at the desired operating frequency, and upon passing through resonant cavities generates radio-frequency power for accelerating the main beam. Among the different approaches to the production of a suitable drive beam, the use of an FEL has been proposed and is under active study at CEA/CESTA.

Extensions of MAD Version 8 to Include Beam Acceleration

International Nuclear Information System (INIS)

Raubenheimer, Tor O

2000-01-01

In this paper, the authors describe modifications to MAD version 8.23 to include linear accelerator cavities and beam acceleration. An additional energy variable has been added which is modified as the beam passes through LCAV elements (linear accelerator cavities) and can be used as a constraint in matching commands. The calculation of the beta functions and phase advance is consistent with that in other codes that treat acceleration such as TRANSPORT or DIMAD. These modifications allow this version of MAD to be used for the design and modeling of linacs and the authors present examples from the Next Linear Collider design as well as a muon acceleration complex. The code is available from CERN or SLAC

Proton-antiproton colliding beam electron cooling

International Nuclear Information System (INIS)

Derbenev, Ya.S.; Skrinskij, A.N.

1981-01-01

A possibility of effective cooling of high-energy pp tilde beams (E=10 2 -10 3 GeV) in the colliding mode by accompanying radiationally cooled electron beam circulating in an adjacent storage ring is studied. The cooling rate restrictions by the pp tilde beam interaction effects while colliding and the beam self-heating effect due to multiple internal scattering are considered. Some techniques permitting to avoid self-heating of a cooling electron beam or suppress its harmful effect on a heavy particle beam cooling are proposed. According to the estimations the cooling time of 10 2 -10 3 s order can be attained [ru

BROOKHAVEN: Booster boost

International Nuclear Information System (INIS)

Anon.

1993-01-01

After three months of intensive dedicated machine studies, Brookhaven's new Booster accelerated 5 x 10 13 protons over four cycles, about 85% of the design intensity. This was made possible by careful matching of Linac beam into the Booster and by extensive resonance stop band corrections implemented during Booster acceleration. The best single cycle injection into the AGS Alternating Gradient Synchrotron was 1.14 x 10 13 protons from the Booster. 1.05 x 10 13 protons were kept in the AGS, a 92% combined efficiency of extraction, transfer, and injection. The maximum injected 1994 shutdown period, enabling the 1994 physics run to make use of the full Booster intensity and go for the stated AGS objective of 4x10 13 protons per pulse

Beam emittance growth caused by transverse deflecting fields in a linear accelerator

Energy Technology Data Exchange (ETDEWEB)

Chao, A W; Richter, B; Yao, C Y [Stanford Linear Accelerator Center, CA (USA)

1980-12-01

The effect of the beam-generated transverse deflecting fields on the emittance of an intense bunch of particles in a high-energy linear accelerator is analyzed in this paper. The equation of motion is solved by a perturbation method for cases of a coasting beam and a uniformly accelerated beam. The results are applied to obtain some design tolerance specifications for the recently proposed SLAC Single Pass Collider.

ELECTRON BEAM ION SOURCE PRE-INJECTOR DIGNOSTICS

International Nuclear Information System (INIS)

WILINSKI, M.; ALESSI, J.; BEEBE, E.; BELLAVIA, S.; PIKIN, A.

2006-01-01

A new ion pre-injector line is currently under design at Brookhaven National Laboratory (BNL) for the Relativistic Heavy Ion Collider (RHIC) and the NASA Space Radiation Laboratory (NSRL,). Collectively, this new line is referred to as the EBIS project. This pre-injector is based on an Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (R-FQ) accelerator, and a linear accelerator. The new EBIS will be able to produce a wide range of heavy ion species as well as rapidly switching between species. To aid in operation of the pre-injector line, a suite of diagnostics is currently proposed which includes faraday cups, current transformers, profile monitors, and a pepperpot emittance measurement device

Beam-based alignment technique for the SLC [Stanford Linear Collider] linac

International Nuclear Information System (INIS)

Adolphsen, C.E.; Lavine, T.L.; Atwood, W.B.

1989-03-01

Misalignment of quadrupole magnets and beam position monitors (BPMs) in the linac of the SLAC Linear Collider (SLC) cause the electron and positron beams to be steered off-center in the disk-loaded waveguide accelerator structures. Off-center beams produce wakefields which limit the SLC performance at high beam intensities by causing emittance growth. Here, we present a general method for simultaneously determining quadrupole magnet and BPM offsets using beam trajectory measurements. Results from the application of the method to the SLC linac are described. The alignment precision achieved is approximately 100 μm, which is significantly better than that obtained using optical surveying techniques. 2 refs., 4 figs

BROOKHAVEN: Looking towards heavy ion physics

International Nuclear Information System (INIS)

Anon.

1988-01-01

July 11-22 were busy days at Brookhaven with a two-week Summer Institute on Relativistic Heavy Ion Physics. After an intensive first week designed to introduce young physicists to high energy heavy ion research, the second week was a workshop on detector technology for Brookhaven's proposed Relativistic Heavy Ion Collider (RHIC), attended by some 150 physicists

Accelerator physics and technology limitations to ultimate energy and luminosity in very large hadron colliders

Energy Technology Data Exchange (ETDEWEB)

P. Bauer et al.

2002-12-05

The following presents a study of the accelerator physics and technology limitations to ultimate energy and luminosity in very large hadron colliders (VLHCs). The main accelerator physics limitations to ultimate energy and luminosity in future energy frontier hadron colliders are synchrotron radiation (SR) power, proton-collision debris power in the interaction regions (IR), number of events-per-crossing, stored energy per beam and beam-stability [1]. Quantitative estimates of these limits were made and translated into scaling laws that could be inscribed into the particle energy versus machine size plane to delimit the boundaries for possible VLHCs. Eventually, accelerator simulations were performed to obtain the maximum achievable luminosities within these boundaries. Although this study aimed at investigating a general VLHC, it was unavoidable to refer in some instances to the recently studied, [2], 200 TeV center-of-mass energy VLHC stage-2 design (VLHC-2). A more thorough rendering of this work can be found in [3].

Beam losses monitor for superconducting accelerators

International Nuclear Information System (INIS)

Kurochkin, I.A.; Lapitskij, S.N.; Mokhov, N.V.; Seleznev, V.S.

1991-01-01

A special beam losses monitor (BLM) for SC accelerators -colliders as an integral part od SC magnet (quadrupole or/and corrector) design is proposed. The main BLM parameters calculated under the real UNK and SSC conditions are presented in comparison with the traditional BLM ones which is planned to be used at SSC now. 9 refs.; 4 figs.; 2 tabs

Precise and fast beam energy measurement at the international linear collider

International Nuclear Information System (INIS)

Viti, Michele

2010-02-01

The international Linear Collider (ILC) is an electron-positron collider with a center-of-mass energy between 200 and 500 GeV and a peak luminosity of 2 . 10 34 cm -2 s -1 . For the physics program at this machine, an excellent bunch-by-bunch control of the beam energy is mandatory. Several techniques are foreseen to be implemented at the ILC in order to achieve this request. Energy spectrometers upstream and downstream of the electron/positron interaction point were proposed and the present default option for the upstream spectrometer is a beam position monitor based (BPM-based) spectrometer. In 2006/2007, a prototype of such a device was commissioned at the End Station A beam line at the Stanford Linear Accelerator Center (SLAC) in order to study performance and reliability. In addition, a novel method based on laser Compton backscattering has been proposed, since as proved at the Large Electron-Positron Collider (LEP) and the Stanford Linear Collider (SLC), complementary methods are necessary to cross-check the results of the BPM-based spectrometer. In this thesis, an overview of the experiment at End Station A is given, with emphasis on the performance of the magnets in the chicane and first energy resolution estimations. Also, the novel Compton backscattering method is discussed in details and found to be very promising. It has the potential to bring the beam energy resolution well below the requirement of ΔE b /E b =10 -4 . (orig.)

TeV e+e- linear colliders

International Nuclear Information System (INIS)

Le Duff, J.

1987-12-01

The basic philosophy and performance and technical constraints of linear e + e - colliders at TeV energies are summarized. Collider luminosity, pinch effects due to beam interaction, beam-beam bremsstrahlung, and typical parameters for an e + e - linear collider are discussed. Accelerating structures, HF power sources, electron guns, positron production, and storage rings are considered [fr

eγ and γγ colliders

International Nuclear Information System (INIS)

Watanabe, Isamu

1994-01-01

The results that can be expected by eγ and γγ colliders in future are summarized. eγ and γγ colliders have many fine possibilities, and are the economical selection for utilizing future e + e - colliders more effectively. eγ and γγ colliders were proposed by former USSR researchers at the beginning of 1980s, but recently, the prospect of realizing future e + e - collision type linear accelerator projects has become high, they have become to be considered seriously as the option of remodeling them. The high energy photon beam of eγ and γγ colliders is obtained by causing Compton reverse scattering, irradiating laser beam to the electron beam of e + e - accelerators. The production of γ-beam is explained. As for the physics noteworthy in eγ colliders, abnormal gauge coupling, the formation of Higgs particles, excited leptons, lepto-quark, supersymmetric particles and top quark are explained. As the physics noteworthy in γγ colliders, the formation of Higgs particles which is most interesting in γγ colliders, abnormal gauge coupling, top quark, Yukawa coupling, Higgs pair formation and other particles are enumerated. The linear e + e - accelerators of TeV range including JLC have the performance to be remodeled to eγ and γγ colliders, and the prospect of realizing them has become high. Their possibility of realization is discussed. (K.I.)

BNL accelerator plans

International Nuclear Information System (INIS)

Lowenstein, D.I.

1986-01-01

The Brookhaven National Laboratory plan for high energy and heavy ion physics accelerator use for the next ten-year period is described. The two major initiatives are in the construction of the Relativistic Heavy Ion Collider and the upgrade of the Alternating Gradient Synchrotron to a ''Mini Kaon Factory''

Symmetrization of the beam-beam interaction in an asymmetric collider

International Nuclear Information System (INIS)

Chin, Y.H.

1990-07-01

This paper studies the idea of symmetrizing both the lattice and the beams of an asymmetric collider, and discusses why this regime should be within the parametric reach of the design in order to credibly ensure its performance. Also examined is the effectiveness of a simple compensation method using the emittance as a free parameter and that it does not work in all cases. At present, when there are no existing asymmetric colliders, it seems prudent to design an asymmetric collider so as to be similar to a symmetric one (without relying on a particular theory of the asymmetric beam-beam interaction that has not passed tests of fidelity). Nevertheless, one must allow for the maximum possible flexibility and freedom in adjusting those parameters that affect luminosity. Such a parameter flexibility will be essential in tuning the collider to the highest luminosity

Collider and Detector Protection at Beam Accidents

Science.gov (United States)

Rakhno, I. L.; Mokhov, N. V.; Drozhdin, A. I.

2003-12-01

Dealing with beam loss due to abort kicker prefire is considered for hadron colliders. The prefires occured at Tevatron (Fermilab) during Run I and Run II are analyzed and a protection system implemented is described. The effect of accidental beam loss in the Large Hadron Collider (LHC) at CERN on machine and detector components is studied via realistic Monte Carlo calculations. The simulations show that beam loss at an unsynchronized beam abort would result in severe heating of conventional and superconducting magnets and possible damage to the collider detector elements. A proposed set of collimators would reduce energy deposition effects to acceptable levels. Special attention is paid to reducing peak temperature rise within the septum magnet and minimizing quench region length downstream of the LHC beam abort straight section.

Collider and Detector Protection at Beam Accidents

International Nuclear Information System (INIS)

Rakhno, I.L.; Mokhov, N.V.; Drozhdin, A.I.

2003-01-01

Dealing with beam loss due to abort kicker prefire is considered for hadron colliders. The prefires occurred at Tevatron (Fermilab) during Run I and Run II are analyzed and a protection system implemented is described. The effect of accidental beam loss in the Large Hadron Collider (LHC) at CERN on machine and detector components is studied via realistic Monte Carlo calculations. The simulations show that beam loss at an unsynchronized beam abort would result in severe heating of conventional and superconducting magnets and possible damage to the collider detector elements. A proposed set of collimators would reduce energy deposition effects to acceptable levels. Special attention is paid to reducing peak temperature rise within the septum magnet and minimizing quench region length downstream of the LHC beam abort straight section

Collider and detector protection at beam accidents

International Nuclear Information System (INIS)

Rakhno, I.L.; Mokhov, N.V.; Drozhdin, A.I.

2003-01-01

Dealing with beam loss due to abort kicker prefire is considered for hadron colliders. The prefires occurred at Tevatron (Fermilab) during Run I and Run II are analyzed and a protection system implemented is described. The effect of accidental beam loss in the Large Hadron Collider (LHC) at CERN on machine and detector components is studied via realistic Monte Carlo calculations. The simulations show that beam loss at an unsynchronized beam abort would result in severe heating of conventional and superconducting magnets and possible damage to the collider detector elements. A proposed set of collimators would reduce energy deposition effects to acceptable levels. Special attention is paid to reducing peak temperature rise within the septum magnet and minimizing quench region length downstream of the LHC beam abort straight section

Digital transverse beam dampers from the Brookhaven AGS

International Nuclear Information System (INIS)

Smith, G.A.; Castillo, V.; Roser, T.; Van Asselt, W.; Witkover, R.; Wong, V.

1995-01-01

A wide band, digital damper system has been developed and is in use at the Brookhaven Alternating Gradient Synchrotron (AGS). The system consists of vertical and horizontal capacitive pickups, analog and digital processing electronics, four 500 Watt wide band power amplifiers, and two pairs of strip line beam kickers. The system is currently used to damp transverse coherent instabilities and injection errors, in both planes, for protons and all species of heavy ions. This paper discusses the system design and operation, particularly with regard to stabilization of the high intensity proton beam. The analog and digital signal processing techniques used to achieve optimum results are discussed. Operational data showing the effect of the damping are presented

Brookhaven collider opens its quest for Big Bang conditions

CERN Multimedia

Nadis, S

2000-01-01

The collision of two gold nuclei releasing 10 x 10 to the power 12 electron volts of energy, marked the debut of the Relativistic Heavy Ion Collider. Over the next few weeks, scientists hope to increase the accelerator's power to generate collisions 40 x 10 to the power 12 eVs of energy to simulate the conditions that existed immediately after the Big Bang (1 page).

A Beam Interlock System for CERN High Energy Accelerators

CERN Document Server

Todd, Benjamin; Schmidt, R

2006-01-01

The Large Hadron Collider (LHC) at CERN (The European Organisation for Nuclear Research) is one of the largest and most complicated machines envisaged to date. The LHC has been conceived and designed over the course of the last 25 years and represents the cutting edge of accelerator technology with a collision energy of 14TeV, having a stored beam energy over 100 times more powerful than the nearest competitor. Commissioning of the machine is already nderway and operation with beam is intended for Autumn 2007, with 7TeV operation expected in 2008. The LHC is set to answer some of the fundemental questions in theoretical physics, colliding particles with such high energy that the inner workings of the quantum world can be revealed. Colliding particles together at such high energy makes very high demands on machine operation and protection. The specified beam energy requires strong magnetic fields that are made in superconducting dipole magnets, these magnets are kept only around two degrees above absolute zero...

Combined phenomena of beam-beam and beam-electron cloud interactionsin circular e^{+}e^{-} colliders

Directory of Open Access Journals (Sweden)

Kazuhito Ohmi

2002-10-01

Full Text Available An electron cloud causes various effects in high intensity positron storage rings. The positron beam and the electron cloud can be considered a typical two-stream system with a certain plasma frequency. Beam-beam interaction is another important effect for high luminosity circular colliders. Colliding two beams can be considered as a two-stream system with another plasma frequency. We study the combined phenomena of the beam-electron cloud and beam-beam interactions from a viewpoint of two complex two-stream effects with two plasma frequencies.

Precise and fast beam energy measurement at the international linear collider

Energy Technology Data Exchange (ETDEWEB)

Viti, Michele

2010-02-15

The international Linear Collider (ILC) is an electron-positron collider with a center-of-mass energy between 200 and 500 GeV and a peak luminosity of 2 . 10{sup 34} cm{sup -2}s{sup -1}. For the physics program at this machine, an excellent bunch-by-bunch control of the beam energy is mandatory. Several techniques are foreseen to be implemented at the ILC in order to achieve this request. Energy spectrometers upstream and downstream of the electron/positron interaction point were proposed and the present default option for the upstream spectrometer is a beam position monitor based (BPM-based) spectrometer. In 2006/2007, a prototype of such a device was commissioned at the End Station A beam line at the Stanford Linear Accelerator Center (SLAC) in order to study performance and reliability. In addition, a novel method based on laser Compton backscattering has been proposed, since as proved at the Large Electron-Positron Collider (LEP) and the Stanford Linear Collider (SLC), complementary methods are necessary to cross-check the results of the BPM-based spectrometer. In this thesis, an overview of the experiment at End Station A is given, with emphasis on the performance of the magnets in the chicane and first energy resolution estimations. Also, the novel Compton backscattering method is discussed in details and found to be very promising. It has the potential to bring the beam energy resolution well below the requirement of {delta}E{sub b}/E{sub b}=10{sup -4}. (orig.)

High luminosity polarized proton collisions at RHIC

International Nuclear Information System (INIS)

Roser, T.

2001-01-01

The Brookhaven Relativistic Heavy Ion Collider (RHIC) provides the unique opportunity to collide polarized proton beams at a center-of-mass energy of up to 500 GeV and luminosities of up to 2 x 10 32 cm -2 s -1 . Such high luminosity and high energy polarized proton collisions will open up the possibility of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. After successful operation of RHIC with gold beams polarized protons from the AGS have been successfully injected into RHIC and accelerated using a full Siberian snakes built from four superconducting helical dipoles. A new high energy proton polarimeter was also successfully commissioned. Operation with two snakes per RHIC ring is planned for next year

Heavy ion collisions at collider energies – Insights from PHENIX

Indian Academy of Sciences (India)

44KFKI Research Institute for Particle and Nuclear Physics (RMKI), Budapest, Hungary†. 1. Introduction. PHENIX is one of the five experiments at the recently commissioned RHIC collider at. Brookhaven National Laboratory. During the year 2000 first data with gold beams were taken at a center-of-mass energy of 130 GeV.

Observations and open questions in beam-beam interactions

International Nuclear Information System (INIS)

Sen, Tanaji

2010-01-01

The first of the hadron colliders, ISR, started operation in 1970. In the following years, the hadron colliders to follow were the SPS (started 1980), the Tevatron (started 1987 first as a fixed target machine), RHIC (started 2000) and most recently the LHC, which started in 2008. HERA was a hybrid that collided electrons and protons. All of these accelerators had or have their performance limited by the effects of the beam-beam interactions. That has also been true for the electron-positron colliders such as LEP, CESR, KEKB and PEPII. In this article I will discuss how the beam-beam limitations arose in some of these machines. The discussion will be focused on common themes that span the different colliders. I will mostly discuss the hadron colliders but sometimes discuss the lepton colliders where relevant. Only a handful of common accelerator physics topics are chosen here, the list is not meant to be exhaustive. A comparative review of beam-beam performance in the ISR, SPS and Tevatron (ca 1989) can be found in reference. Table 1 shows the relevant parameters of colliders (excluding the LHC), which have accelerated protons.

Report of the 1983 HEPAP Subpanel on New Facilities for the US high-energy physics program

International Nuclear Information System (INIS)

1983-07-01

The 1983 Subpanel on New Facilities of the High Energy Physics Advisory Panel (HEPAP) was formed in February 1983 and completed its report in July 1983. During the intervening 5 months the Subpanel held site meetings at three major accelerator laboratories, heard formal presentations from a number of prominent physicists, received almost 200 letters from members of the high energy physics community, and studied in depth all of the relevant written material. The final recommendations were arrived at after two lengthy deliberative meetings held in June and July at the National Academy of Sciences (NAS) Study Center at Woods Hole, Massachusetts, and at the Nevis Laboratory, Columbia University. The recommendations arrived at by the Subpanel are as follows: (1) the Subpanel unanimously recommends the immediate initiation of a multi-TeV high-luminosity proton-proton collider project with the goal of physics experiments at this facility at the earliest possible date; (2) the Subpanel recommends the rapid completion of current construction projects, Tevatron and the SLAC Linear Collider (SLC), the upgrading of the Cornell Electron Storage Ring (CESR) and associated detectors, and the thorough utilization of all existing facilities; (3) the Subpanel recommends that Fermilab not proceed at this time with the Dedicated Collider (DC); (4) by a majority vote, the Subpanel recommends that the Colliding Beam Accelerator (CBA) project at Brookhaven not be approved; (5) the Subpanel recommends that technology research and development, particularly advanced accelerator research and development, be strongly supported

Accelerator Physics for ILC and CLIC

CERN Document Server

Zimmermann, F

2010-01-01

This paper summarizes the second part of the “accelerator physics lectures” delivered at the Ambleside Linear Collider School 2009. It discusses more specific linear-collider issues: superconducting and room-temperature linear accelerators, particle sources for electrons and positrons, synchrotron radiation and damping, intensity limits, beam stability, and beam delivery system – including final focus, collimation, and beam-beam effects. It also presents an overview of the International Linear Collider (ILC), a description of the two beam acceleration scheme of the Compact Linear Collider (CLIC), and a comparison of the ILC and CLIC parameters.

Acceleration of high charge density electron beams in the SLAC linac

International Nuclear Information System (INIS)

Sheppard, J.C.; Clendenin, J.E.; Jobe, R.K.; Lueth, V.G.; Millich, A.; Ross, M.C.; Seeman, J.T.; Stiening, R.F.

1984-01-01

The SLAC Linear Collider (SLC) will require both electron and positron beams of very high charge density and low emittance to be accelerated to about 50 GeV in the SLAC 3-km linac. The linac is in the process of being improved to meet this requirement. The program to accelerate an electron beam of high charge density through the first third of the SLC linac is described and the experimental results are discussed. 7 references, 5 figures

Importance of beam-beam tune spread to collective beam-beam instability in hadron colliders

International Nuclear Information System (INIS)

Jin Lihui; Shi Jicong

2004-01-01

In hadron colliders, electron-beam compensation of beam-beam tune spread has been explored for a reduction of beam-beam effects. In this paper, effects of the tune-spread compensation on beam-beam instabilities were studied with a self-consistent beam-beam simulation in model lattices of Tevatron and Large Hodron Collider. It was found that the reduction of the tune spread with the electron-beam compensation could induce a coherent beam-beam instability. The merit of the compensation with different degrees of tune-spread reduction was evaluated based on beam-size growth. When two beams have a same betatron tune, the compensation could do more harm than good to the beams when only beam-beam effects are considered. If a tune split between two beams is large enough, the compensation with a small reduction of the tune spread could benefit beams as Landau damping suppresses the coherent beam-beam instability. The result indicates that nonlinear (nonintegrable) beam-beam effects could dominate beam dynamics and a reduction of beam-beam tune spread by introducing additional beam-beam interactions and reducing Landau damping may not improve the stability of beams

Accelerator Based Neutron Beams for Neutron Capture Therapy

International Nuclear Information System (INIS)

Yanch, Jacquelyn C.

2003-01-01

compared the RBE characteristics of the MIT Reactor M67 clinical beam, The Brookhaven Medical Research Reactor clinical beam (both of which were used in Phase I/II clinical trials of BNCT) and the MIT LABA BNCS beam. Additional research initiated under this program involved an investigation of the potential of BNCT for the prevention of restenosis and the development of accelerator-based fast neutron brachytherapy. A total of 10 student research theses (2 Undergraduate, 4 Masters, and 4 Doctoral) were completed as part of this research program

Inverse free-electron laser accelerator development

International Nuclear Information System (INIS)

Fisher, A.; Gallardo, J.; Steenbergen, A. van; Sandweiss, J.; Fang, J.M.

1994-06-01

The study of the Inverse Free-Electron Laser, as a potential mode of electron acceleration, has been pursued at Brookhaven National Laboratory for a number of years. More recent studies focused on the development of a low energy (few GeV), high gradient, multistage linear accelerator. The authors are presently designing a short accelerator module which will make use of the 50 MeV linac beam and high power (2 x 10 11 W) CO 2 laser beam of the Accelerator Test Facility (ATF) at the Center for Accelerator Physics (CAP), Brookhaven National Laboratory. These elements will be used in conjunction with a fast excitation (300 μsec pulse duration) variable period wiggler, to carry out an accelerator demonstration stage experiment

Beam-beam instability driven by wakefield effects in linear colliders

CERN Document Server

Brinkmann, R; Schulte, Daniel

2002-01-01

The vertical beam profile distortions induced by wakefield effects in linear colliders (the so-called ``banana effect'') generate a beam-beam instability at the collision point when the vertical disruption parameter is large. We illustrate this effect in the case of the TESLA linear collider project. We specify the tolerance on the associated emittance growth, which translates into tolerances on injection jitter and, for a given tuning procedure, on structure misalignments. We look for possible cures based on fast orbit correction at the interaction point and using a fast luminosity monitor.

Application of International Linear Collider superconducting cavities for acceleration of protons

Directory of Open Access Journals (Sweden)

P. N. Ostroumov

2007-12-01

Full Text Available Beam acceleration in the International Linear Collider (ILC will be provided by 9-cell 1300 MHz superconducting (SC cavities. The cavities are designed for effective acceleration of charged particles moving with the speed of light and are operated on π-mode to provide a maximum accelerating gradient. A significant research and development effort has been devoted to develop ILC SC technology and its rf system which resulted in excellent performance of ILC cavities. Therefore, the proposed 8-GeV proton driver in Fermilab is based on ILC cavities above ∼1.2  GeV. The efficiency of proton beam acceleration by ILC cavities drops fast for lower velocities and it was proposed to develop squeezed ILC-type (S-ILC cavities operating at 1300 MHz and designed for β_{G}=0.81, geometrical beta, to accelerate protons or H^{-} from ∼420  MeV to 1.2 GeV. This paper discusses the possibility of avoiding the development of new β_{G}=0.81 cavities by operating ILC cavities on 8/9π-mode of standing wave oscillations.

Optimisation analysis and improvement of the effective beam sizes in Accelerator Test Facility 2

CERN Document Server

AUTHOR|(CDS)2082063; Kisiel, Adam

2016-10-20

A lepton linear collider is considered by the accelerator and particle physics communities as an appropriate machine to perform high precision particle physics research in the TeV energy regime. There are two proposals for the future e+e- linear collider: the Compact Linear Collider (CLIC) and the International Linear Collider (ILC), both developed by two wide international collaborations with strong overlap between them. Both designs satisfy the particle physics requirements. At the TeV energy regime the cross sections of many processes of interest are small, therefore large luminosities on the order of 10^{34} cm^{-2}s^{-1} at the interaction point (IP) are required to deliver the required event rates. The luminosity inversely depends on the transverse size of the colliding beams which restricts the beam sizes at the IP to the nanometer level. The strong focusing of the beams occurs in the final focus system (FFS), the most inner part of a linear collider, where the beams are focused at the IP by means of t...

SLAC linear collider conceptual design report

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

The linear collider system is described in detail, including the transport system, the collider lattice, final focusing system, positron production, beam damping and compression, high current electron source, instrumentation and control, and the beam luminosity. The experimental facilities and the experimental uses are discussed along with the construction schedule and estimated costs. Appendices include a discussion of space charge effects in the linear accelerator, emittance growth in the collider, the final focus system, beam-beam instabilities and pinch effects, and detector backgrounds. (GHT)

SLAC linear collider conceptual design report

International Nuclear Information System (INIS)

1980-06-01

The linear collider system is described in detail, including the transport system, the collider lattice, final focusing system, positron production, beam damping and compression, high current electron source, instrumentation and control, and the beam luminosity. The experimental facilities and the experimental uses are discussed along with the construction schedule and estimated costs. Appendices include a discussion of space charge effects in the linear accelerator, emittance growth in the collider, the final focus system, beam-beam instabilities and pinch effects, and detector backgrounds

Modelling of the Thermo-Mechanical Behavior of the Two-Beam Module for the Compact Linear Collider

CERN Document Server

Raatikainen, Riku; Österberg, K; Lehtovaara, A; Pajunen, S

2011-01-01

To fulfil the mechanical requirements set by the luminosity goals of the compact linear collider, the 2-m long two-beam modules, the shortest repetitive elements in the main linear accelerator, have to be controlled at micrometer level. At the same time these modules are exposed to high power dissipation that varies while the accelerator is ramped up to nominal power and when the mode of the accelerator operation is modified. These variations will give rise to inevitable temperature transients driving mechanical distortions in and between different module components. Therefore, the thermo-mechanical behaviour of the module is of a high importance. This thesis describes a finite element method model for the two-beam compact linear collider module. The components are described in detail compared to earlier models, which should result in a realistic description of the module. Due to the complexity of the modules, the modelling is divided into several phases from geometrical simplification and modification to the...

Conceptual design of hollow electron lenses for beam halo control in the Large Hadron Collider

CERN Document Server

Stancari, Giulio; Valishev, Alexander; Bruce, Roderik; Redaelli, Stefano; Rossi, Adriana; Salvachua Ferrando, Belen

2014-01-01

Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. Within the US LHC Accelerator Research Program (LARP) and the European FP7 HiLumi LHC Design Study, we are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. The expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were check...

Brookhaven highlights, October 1978-September 1979

International Nuclear Information System (INIS)

1979-01-01

These highlights present an overview of the major research and development achievements at Brookhaven National Laboratory from October 1978 to September 1979. Specific areas covered include: accelerator and high energy physics programs; high energy physics research; the AGS and improvements to the AGS; neutral beam development; heavy ion fusion; superconducting power cables; ISABELLE storage rings; the BNL Tandem accelerator; heavy ion experiments at the Tandem; the High Flux Beam Reactor; medium energy physics; nuclear theory; atomic and applied physics; solid state physics; neutron scattering studies; x-ray scattering studies; solid state theory; defects and disorder in solids; surface physics; the National Synchrotron Light Source ; Chemistry Department; Biology Department; Medical Department; energy sciences; environmental sciences; energy technology programs; National Center for Analysis of Energy Systems; advanced reactor systems; nuclear safety; National Nuclear Data Center; nuclear materials safeguards; Applied Mathematics Department; and support activities

Beam instrumentation for the Tevatron Collider

Energy Technology Data Exchange (ETDEWEB)

Moore, Ronald S.; Jansson, Andreas; Shiltsev, Vladimir; /Fermilab

2009-10-01

The Tevatron in Collider Run II (2001-present) is operating with six times more bunches and many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for future colliders.

Future Hadron Colliders

CERN Document Server

Keil, Eberhard

1998-01-01

Plans for future hadron colliders are presented, and accelerator physics and engineering aspects common to these machines are discussed. The Tevatron is presented first, starting with a summary of the achievements in Run IB which finished in 1995, followed by performance predictions for Run II which will start in 1999, and the TeV33 project, aiming for a peak luminosity $L ~ 1 (nbs)^-1$. The next machine is the Large Hadron Collider LHC at CERN, planned to come into operation in 2005. The last set of machines are Very Large Hadron Colliders which might be constructed after the LHC. Three variants are presented: Two machines with a beam energy of 50 TeV, and dipole fields of 1.8 and 12.6 T in the arcs, and a machine with 100 TeV and 12 T. The discussion of accelerator physics aspects includes the beam-beam effect, bunch spacing and parasitic collisions, and the crossing angle. The discussion of the engineering aspects covers synchrotron radiation and stored energy in the beams, the power in the debris of the p...

Beam Position Monitor and Energy Analysis at the Fermilab Accelerator Science and Technology Facility

Energy Technology Data Exchange (ETDEWEB)

Lopez, David Juarez [Univ. of Guanajuato (Mexico)

2015-08-01

Fermilab Accelerator Science and Technology Facility has produced its first beam with an energy of 20 MeV. This energy is obtained by the acceleration at the Electron Gun and the Capture Cavity 2 (CC2). When fully completed, the accelerator will consist of a photoinjector, one International Liner Collider (ILC)-type cryomodule, multiple accelerator R&D beamlines, and a downstream beamline to inject 300 MeV electrons into the Integrable Optics Test Accelerator (IOTA). We calculated the total energy of the beam and the corresponding energy to the Electron Gun and CC2. Subsequently, a Beam Position Monitors (BPM) error analysis was done, to calculate the device actual resolution.

ACCELERATION OF POLARIZED BEAMS USING MULTIPLE STRONG PARTIAL SIBERIAN SNAKES

International Nuclear Information System (INIS)

ROSER, T.; AHRENS, L.; BAI, M.

2004-01-01

Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult since depolarizing spin resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions. Using a 20-30% partial Siberian snake both imperfection and intrinsic resonances can be overcome. Such a strong partial Siberian snake was designed for the Brookhaven AGS using a dual pitch helical superconducting dipole. Multiple strong partial snakes are also discussed for spin matching at beam injection and extraction

Studies of beam dynamics in relativistic klystron two-beam accelerators

Energy Technology Data Exchange (ETDEWEB)

Lidia, Steven M.

1999-11-01

Two-beam accelerators (TBAs) based upon free-electron lasers (FELs) or relativistic klystrons (RK-TBAs) have been proposed as efficient power sources for next generation high-energy linear colliders. Studies have demonstrated the possibility of building TBAs from X-band (~8-12 GHz) through Ka band (~ 30-35 GHz) frequency regions. Provided that further prototyping shows stable beam propagation with minimal current loss and production of good quality, high-power rf fields, this technology is compatible with current schemes for electron-positron colliders in the multi-TeV center-of-mass scale. A new method of simulating the beam dynamics in accelerators of this type has been developed in this dissertation. There are three main components to this simulation. The first is a tracking algorithm to generate nonlinear transfer maps for pushing noninteracting particles through the external fields. The second component is a 3D Particle-In-Cell (PIC) algorithm that solves a set of Helmholtz equations for the self-fields, including the conducting boundary condition, and generates impulses that are interleaved with the nonlinear maps by means of a split-operation algorithm. The Helmholtz equations are solved by a multi-grid algorithm. The third component is an equivalent circuit equation solver that advances the modal rf cavity fields in time due to excitation by the modulated beam. The RTA project is described, and the simulation code is used to design the latter portions of the experiment. Detailed calculations of the beam dynamics and of the rf cavity output are presented and discussed. A beamline design is presented that will generate nearly 1.2 GW of power from 40 input, gain, and output rv cavities over a 10 m distance. The simulations show that beam current losses are acceptable, and that longitudinal and transverse focusing techniques are sufficient capable of maintaining a high degree of beam quality along the entire beamline. Additional experimental efforts are also

Wakefield damping in a pair of X-band accelerators for linear colliders

Directory of Open Access Journals (Sweden)

Roger M. Jones

2006-10-01

Full Text Available We consider the means to damp the wakefield left behind ultrarelativistic charges. In particular, we focus on a pair of traveling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wakefield left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wakefield on trailing bunches. This method entails detuning the characteristic mode frequencies which make up the electromagnetic field, damping the wakefield, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wakefield and modes, based on a circuit model, are compared with experimental measurements of the wakefield conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wakefields in a future linear collider consisting of several thousand of these accelerating structures.

Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders

International Nuclear Information System (INIS)

Jones, R.M.; Adolphsen, C.E.; Wang, J.W.; Li, Z.; SLAC

2006-01-01

We consider means to damp the wake-field left behind ultra-relativistic charges. In particular, we focus on a pair of travelling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wake-field left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wake-field on trailing bunches. This method entails detuning the characteristic mode frequencies which make-up the electromagnetic field, damping the wake-field, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wake-field and modes, based on a circuit model, are compared with experimental measurements of the wake-field conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wake-fields in a future linear collider consisting of several thousand of these accelerating structures

Intense beams at the micron level for the Next Linear Collider

International Nuclear Information System (INIS)

Seeman, J.T.

1991-08-01

High brightness beams with sub-micron dimensions are needed to produce a high luminosity for electron-positron collisions in the Next Linear Collider (NLC). To generate these small beam sizes, a large number of issues dealing with intense beams have to be resolved. Over the past few years many have been successfully addressed but most need experimental verification. Some of these issues are beam dynamics, emittance control, instrumentation, collimation, and beam-beam interactions. Recently, the Stanford Linear Collider (SLC) has proven the viability of linear collider technology and is an excellent test facility for future linear collider studies

BROOKHAVEN: RHIC installation

International Nuclear Information System (INIS)

Anon.

1994-01-01

This summer, the first superconducting magnet was installed in 3.8 kilometre tunnel for Brookhaven's RHIC heavy ion collider (October, page 31). Manufactured by Northrop Grumman's Electronics and System Integration Division, the magnet is the first of RHIC's 373 dipoles. In addition to the dipoles, Northrop Grumman will also provide 432 RHIC quadrupoles. The first quadrupole was delivered on 8 April, a month before the first dipole arrived for onsite testing prior to installation. RHIC will need 1,700 superconducting magnets - dipoles, quadrupoles, sextupoles and correcting magnets, 1,200 of which will be built by industry and the rest built at Brookhaven. The 300 sextupoles are being supplied by Everson Electric

Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider

International Nuclear Information System (INIS)

Yu, S.; Goffeney, N.; Henestroza, E.

1995-01-01

A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported

Controlling multibunch beam breakup in TeV linear colliders

International Nuclear Information System (INIS)

Thompson, K.A.; Ruth, R.D.

1989-01-01

To obtain luminosities near 10 34 cm/sup /minus/2/sec/sup /minus/1/ in a TeV linear collider, it will probably be essential to accelerate many bunches per RF fill in order to increase the energy transfer efficiency. In this paper we study the transverse dynamics of multiple bunches in a linac, and we examine the effects of several methods of controlling the beam blow-up that would otherwise be induced by transverse dipole wake fields. The methods we study are: damping the transverse modes, adjusting the frequency of the dominant transverse modes so that bunches may be placed near zero-crossings of the transverse wake, and bunch-to-bunch variation of the transverse focusing. We study the utility of these cures in the main linacs of an example of a TeV collider. 16 refs., 4 figs., 2 tabs

The Computer Program LIAR for Beam Dynamics Calculations in Linear Accelerators

International Nuclear Information System (INIS)

Assmann, R.W.; Adolphsen, C.; Bane, K.; Raubenheimer, T.O.; Siemann, R.H.; Thompson, K.

2011-01-01

Linear accelerators are the central components of the proposed next generation of linear colliders. They need to provide acceleration of up to 750 GeV per beam while maintaining very small normalized emittances. Standard simulation programs, mainly developed for storage rings, do not meet the specific requirements for high energy linear accelerators. We present a new program LIAR ('LInear Accelerator Research code') that includes wakefield effects, a 6D coupled beam description, specific optimization algorithms and other advanced features. Its modular structure allows to use and to extend it easily for different purposes. The program is available for UNIX workstations and Windows PC's. It can be applied to a broad range of accelerators. We present examples of simulations for SLC and NLC.

Beam vacuum system of Brookhaven's muon storage ring

International Nuclear Information System (INIS)

Hseuth, H.C.; Snydstrup, L.; Mapes, M.

1995-01-01

A storage ring with a circumference of 45 m is being built at Brookhaven to measure the g-2 value of the muons to an accuracy of 0.35 ppm.. The beam vacuum system of the storage ring will operate at 10 -7 Torr and has to be completely non-magnetic. It consists of twelve sector chambers. The chambers are constructed of aluminum and are approximately 3.5 m in length with a rectangular cross-section of 16.5 cm high by 45 cm at the widest point. The design features, fabrication techniques and cleaning methods for these chambers are described. The beam vacuum system will be pumped by forty eight non-magnetic distributed ion pumps with a total pumping speed of over 2000 ell/sec. Monte Carlo simulations of the pressure distribution in the muon storage region are presented

SLAC linear collider

International Nuclear Information System (INIS)

Richter, B.; Bell, R.A.; Brown, K.L.

1980-06-01

The SLAC LINEAR COLLIDER is designed to achieve an energy of 100 GeV in the electron-positron center-of-mass system by accelerating intense bunches of particles in the SLAC linac and transporting the electron and positron bunches in a special magnet system to a point where they are focused to a radius of about 2 microns and made to collide head on. The rationale for this new type of colliding beam system is discussed, the project is described, some of the novel accelerator physics issues involved are discussed, and some of the critical technical components are described

Beam-Based Error Identification and Correction Methods for Particle Accelerators

CERN Document Server

AUTHOR|(SzGeCERN)692826; Tomas, Rogelio; Nilsson, Thomas

2014-06-10

Modern particle accelerators have tight tolerances on the acceptable deviation from their desired machine parameters. The control of the parameters is of crucial importance for safe machine operation and performance. This thesis focuses on beam-based methods and algorithms to identify and correct errors in particle accelerators. The optics measurements and corrections of the Large Hadron Collider (LHC), which resulted in an unprecedented low β-beat for a hadron collider is described. The transverse coupling is another parameter which is of importance to control. Improvement in the reconstruction of the coupling from turn-by-turn data has resulted in a significant decrease of the measurement uncertainty. An automatic coupling correction method, which is based on the injected beam oscillations, has been successfully used in normal operation of the LHC. Furthermore, a new method to measure and correct chromatic coupling that was applied to the LHC, is described. It resulted in a decrease of the chromatic coupli...

Polarized proton colliders

International Nuclear Information System (INIS)

Roser, T.

1995-01-01

High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. This will allow the study of the spin structure of the proton and also the verification of the many well documented expectations of spin effects in perturbative QCD and parity violation in W and Z production. Proposals for polarized proton acceleration for several high energy colliders have been developed. A partial Siberian Snake in the AGS has recently been successfully tested and full Siberian Snakes, spin rotators, and polarimeters for RHIC are being developed to make the acceleration of polarized beams to 250 GeV possible. This allows for the unique possibility of colliding two 250 GeV polarized proton beams at luminosities of up to 2 x 10 32 cm -2 s -1

Impact of the resistive wall impedance on beam dynamics in the Future Circular e^{+}e^{-} Collider

Directory of Open Access Journals (Sweden)

M. Migliorati

2018-04-01

Full Text Available The Future Circular Collider study, which aims at designing post-LHC particle accelerator options, is entering in the final stage, which foresees a conceptual design report containing the basic requirements for a hadron and a lepton collider, as well as options for an electron-proton machine. Due to the high beam intensities of these accelerators, collective effects have to be carefully analyzed. Among them, the finite conductivity of the beam vacuum chamber represents a major source of impedance for the electron-positron collider. By using numerical and analytical tools, a parametric study of longitudinal and transverse instabilities caused by the resistive wall is performed in this paper for the case of the Future Circular Collider lepton machine, by taking into account also the effects of coating, used to fight the electron cloud build up. It will be proved that under certain assumptions the coupling impedance of a two layer system does not depend on the conductivity of the coating and this property represents an important characteristic for the choice of the material itself. The results and findings of this study have an impact on the machine design in several aspects. In particular the quite low threshold of single bunch instabilities with respect to the nominal beam current and the not negligible power losses due to the resistive wall are shown, together with the necessity of a new feedback system to counteract the fast transverse coupled bunch instability. The importance of a round vacuum chamber to avoid the quadrupolar tune shift is also discussed. Finally the crucial importance of the beam pipe material coating and thickness choice for the above results is underlined.

Impact of the resistive wall impedance on beam dynamics in the Future Circular e+e- Collider

Science.gov (United States)

Migliorati, M.; Belli, E.; Zobov, M.

2018-04-01

The Future Circular Collider study, which aims at designing post-LHC particle accelerator options, is entering in the final stage, which foresees a conceptual design report containing the basic requirements for a hadron and a lepton collider, as well as options for an electron-proton machine. Due to the high beam intensities of these accelerators, collective effects have to be carefully analyzed. Among them, the finite conductivity of the beam vacuum chamber represents a major source of impedance for the electron-positron collider. By using numerical and analytical tools, a parametric study of longitudinal and transverse instabilities caused by the resistive wall is performed in this paper for the case of the Future Circular Collider lepton machine, by taking into account also the effects of coating, used to fight the electron cloud build up. It will be proved that under certain assumptions the coupling impedance of a two layer system does not depend on the conductivity of the coating and this property represents an important characteristic for the choice of the material itself. The results and findings of this study have an impact on the machine design in several aspects. In particular the quite low threshold of single bunch instabilities with respect to the nominal beam current and the not negligible power losses due to the resistive wall are shown, together with the necessity of a new feedback system to counteract the fast transverse coupled bunch instability. The importance of a round vacuum chamber to avoid the quadrupolar tune shift is also discussed. Finally the crucial importance of the beam pipe material coating and thickness choice for the above results is underlined.

Beam dynamics issues for linear colliders

International Nuclear Information System (INIS)

Ruth, R.D.

1987-09-01

In this paper we discuss various beam dynamics issues for linear colliders. The emphasis is to explore beam dynamics effects which lead to an effective dilution of the emittance of the beam and thus to a loss of luminosity. These considerations lead to various tolerances which are evaluated for a particular parameter set

Report of the group on beam-beam effects in circular colliders

International Nuclear Information System (INIS)

Furman, M.A.

1991-05-01

We present a summary of the discussions and conclusions of the working group on beam-beam effects for circular colliders. This group was part of the larger beam-beam dynamics group at the 7th ICFA Workshop on Beam Dynamics, on the subject ''Beam-Beam and Beam-Radiation Interactions,'' held at UCLA, May 13--16, 1991. 15 refs

Optimum Choice of RF Frequency for Two Beam Linear Colliders

CERN Document Server

Braun, Hans Heinrich

2003-01-01

Recent experimental results on normal conducting RF structures indicate that the scaling of the gradient limit with frequency is less favourable than what was believed. We therefore reconsider the optimum choice of RF frequency and iris aperture for a normal conducting, two-beam linear collider with E_CMS=3 TeV, a loaded accelerating gradient of 150 MV/m and a luminosity of 8 10^34 cm-^2 s^-1. The optimisation criterion is minimizing overall RF costs for investment and operation with constraints put on peak surface electric fields and pulsed heating of accelerating structures. Analytical models are employed where applicable, while interpolation on simulation program results is used for the calculation of luminosity and RF structure properties.

Performance of the Brookhaven photocathode rf gun

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Fernow, R.C.; Fischer, J.; Fisher, A.S.; Gallardo, J.; Ingold, G.; Kirk, H.G.; Leung, K.P.; Malone, R.; Pogorelsky, I.; Srinivasan-Rao, T.; Rogers, J.; Tsang, T.; Sheehan, J.; Ulc, S.; Woodle, M.; Xie, J.; Zhang, R.S.; Lin, L.Y.; McDonald, K.T.; Russell, D.P.; Hung, C.M.; Wang, X.J.

1991-01-01

The Brookhaven Accelerator Test Facility (ATF) uses a photocathode rf gun to provide a high-brightness electron beam intended for FEL and laser-acceleration experiments. The rf gun consists of 1 1/2 cells driven at 2856 MHz in π-mode with a maximum cathode field of 100 MV/m. To achieve long lifetimes, the photocathode development concentrates on robust metals such as copper, yttrium and samarium. We illuminate these cathodes with a 10-ps, frequency-quadrupled Nd:YAG laser. We describe the initial operation of the gun, including measurements of transverse and longitudinal emittance, quantum efficiencies, and peak current. The results are compared to models

The International Linear Collider Technical Design Report - Volume 3.II: Accelerator Baseline Design

CERN Document Server

Adolphsen, Chris; Barish, Barry; Buesser, Karsten; Burrows, Philip; Carwardine, John; Clark, Jeffrey; Durand, Helene Mainaud; Dugan, Gerry; Elsen, Eckhard; Enomoto, Atsushi; Foster, Brian; Fukuda, Shigeki; Gai, Wei; Gastal, Martin; Geng, Rongli; Ginsburg, Camille; Guiducci, Susanna; Harrison, Mike; Hayano, Hitoshi; Kershaw, Keith; Kubo, Kiyoshi; Kuchler, Victor; List, Benno; Liu, Wanming; Michizono, Shinichiro; Nantista, Christopher; Osborne, John; Palmer, Mark; Paterson, James McEwan; Peterson, Thomas; Phinney, Nan; Pierini, Paolo; Ross, Marc; Rubin, David; Seryi, Andrei; Sheppard, John; Solyak, Nikolay; Stapnes, Steinar; Tauchi, Toshiaki; Toge, Nobu; Walker, Nicholas; Yamamoto, Akira; Yokoya, Kaoru

2013-01-01

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to incr...

UCLA accelerator research ampersand development. Progress report

International Nuclear Information System (INIS)

1997-01-01

This report discusses work on advanced accelerators and beam dynamics at ANL, BNL, SLAC, UCLA and Pulse Sciences Incorporated. Discussed in this report are the following concepts: Wakefield acceleration studies; plasma lens research; high gradient rf cavities and beam dynamics studies at the Brookhaven accelerator test facility; rf pulse compression development; and buncher systems for high gradient accelerator and relativistic klystron applications

Final Cooling for a Muon Collider

Energy Technology Data Exchange (ETDEWEB)

Acosta Castillo, John Gabriel [Univ. of Mississippi, Oxford, MS (United States)

2017-05-01

To explore the new energy frontier, a new generation of particle accelerators is needed. Muon colliders are a promising alternative, if muon cooling can be made to work. Muons are 200 times heavier than electrons, so they produce less synchrotron radiation, and they behave like point particles. However, they have a short lifetime of 2.2 $\\mathrm{\\mu s}$ and the beam is more difficult to cool than an electron beam. The Muon Accelerator Program (MAP) was created to develop concepts and technologies required by a muon collider. An important effort has been made in the program to design and optimize a muon beam cooling system. The goal is to achieve the small beam emittance required by a muon collider. This work explores a final ionization cooling system using magnetic quadrupole lattices with a low enough $\\beta^{\\star} $ region to cool the beam to the required limit with available low Z absorbers.

A systems study of an RF power source for a 1 TeV next linear collider based upon the relativistic-klystron two-beam accelerator

International Nuclear Information System (INIS)

Yu, S.; Goffeney, N.; Deadrick, F.

1994-11-01

A systems study, including physics, engineering and costing, has been conducted to assess the feasibility of a relativistic-klystron two-beam-accelerator (RK-TBA) system as a RF power source candidate for a 1 TeV linear collider. Several key issues associated with a realizable RK-TBA system have been addressed, and corresponding schemes have been developed and examined quantitatively. A point design example has been constructed to present a concrete conceptual design which has acceptable transverse and longitudinal beam stability properties. The overall efficiency of RF production for such a power source is estimated to be 36%, and the cost of the full system is estimated to be less than 1 billion dollars

Beam dynamics problems for next generation linear colliders

International Nuclear Information System (INIS)

Yokoya, Kaoru

1990-01-01

The most critical issue for the feasibility of high-energy e + e - linear colliders is obviously the development of intense microwave power sources. Remaining problems, however, are not trivial and in fact some of them require several order-of-magnitude improvement from the existing SLC parameters. The present report summarizes the study status of the beam dynamics problems of high energy linear colliders with an exaggeration on the beam-beam phenomenon at the interaction region. There are four laboratories having linear collider plans, SLAC, CERN, Novosibirsk-Protovino, and KEK. The parameters of these projects scatter in some range but seem to converge slowly if one recalls the status five years ago. The beam energy will be below 500GeV. The basic requirements to the damping ring are the short damping time and small equilibrium emittance. All the proposed designs make use of tight focusing optics and strong wiggler magnets to meet these requirements and seem to have no major problems at least compared with other problems in the colliders. One of the major problems in the linac is the transverse beam blow-up due to the wake field created by the head of the bunch and, in the case of multiple bunches per pulse, by the preceeding bunches. (N.K.)

Linear accelerators for TeV colliders

International Nuclear Information System (INIS)

Wilson, P.B.

1985-05-01

This paper summarizes four tutorial lectures on linear electron accelerators: Electron Linacs for TeV Colliders, Emittance and Damping Rings, Wake Fields: Basic Concepts, and Wake Field Effects in Linacs

FIRST BEAM TESTS OF THE MUON COLLIDER TARGET TEST BEAM LINE AT THE AGS

International Nuclear Information System (INIS)

BROWN, K.A.; GASSNER, D.; GLENN, J.W.; PRIGL, R.; SIMOS, N.; SCADUTO, J.; TSOUPAS, N.

2001-01-01

In this report we will describe the muon collider target test beam line which operates off one branch of the AGS switchyard. The muon collider target test facility is designed to allow a prototype muon collider target system to be developed and studied. The beam requirements for the facility are ambitious but feasible. The system is designed to accept bunched beams of intensities up to 1.6 x 10 13 24 GeV protons in a single bunch. The target specifications require beam spot sizes on the order of 1 mm, 1 sigma rms at the maximum intensity. We will describe the optics design, the instrumentation, and the shielding design. Results from the commissioning of the beam line will be shown

Structural biology facilities at Brookhaven National Laboratory`s high flux beam reactor

Energy Technology Data Exchange (ETDEWEB)

Korszun, Z.R.; Saxena, A.M.; Schneider, D.K. [Brookhaven National Laboratory, Upton, NY (United States)

1994-12-31

The techniques for determining the structure of biological molecules and larger biological assemblies depend on the extent of order in the particular system. At the High Flux Beam Reactor at the Brookhaven National Laboratory, the Biology Department operates three beam lines dedicated to biological structure studies. These beam lines span the resolution range from approximately 700{Angstrom} to approximately 1.5{Angstrom} and are designed to perform structural studies on a wide range of biological systems. Beam line H3A is dedicated to single crystal diffraction studies of macromolecules, while beam line H3B is designed to study diffraction from partially ordered systems such as biological membranes. Beam line H9B is located on the cold source and is designed for small angle scattering experiments on oligomeric biological systems.

Progress in advanced accelerator concepts

International Nuclear Information System (INIS)

Sessler, A.M.

1994-08-01

A review is given of recent progress in this field, drawing heavily upon material presented at the Workshop on Advanced Accelerator Concepts, The Abbey, June 12--18, 1994. Attention is addressed to (1) plasma based concepts, (2) photo-cathodes, (3) radio frequency sources and Two-Beam Accelerators, (4) near and far-field schemes (including collective accelerators), (5) beam handling and conditioning, and (6) exotic collider concepts (such as photon colliders and muon colliders)

Beam-Beam Effects in the SPS Proton-Anti Proton Collider

CERN Document Server

Cornelis, K.

2014-01-01

During the proton-anti proton collider run several experiments were carried out in order to understand the effect of the beam-beam interaction on backgrounds and lifetimes. In this talk a selection of these experiments will be presented. From these experiments, the importance of relative beam sizes and tune ripple could be demonstrated.

Ion Colliders

CERN Document Server

Fischer, W

2014-01-01

High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

Final muon cooling for a muon collider

Science.gov (United States)

Acosta Castillo, John Gabriel

To explore the new energy frontier, a new generation of particle accelerators is needed. Muon colliders are a promising alternative if muon cooling can be made to work. Muons are 200 times heavier than electrons, so they produce less synchrotron radiation, and they behave like point particles. However, they have a short lifetime of 2.2 mus and the beam is more difficult to cool than an electron beam. The Muon Accelerator Program (MAP) was created to develop concepts and technologies required by a muon collider. An important effort has been made in the program to design and optimize a muon beam cooling system. The goal is to achieve the small beam emittance required by a muon collider. This work explores a final ionization cooling system using magnetic quadrupole lattices with a low enough beta* region to cool the beam to the required limit with available low Z absorbers.

Neutrino and muon physics in the collider mode of future accelerators

International Nuclear Information System (INIS)

Rujula, A. de; Rueckl, R.

1984-01-01

Extracted beams and fixed target facilities at future colliders (the SSC and the LHC) may be (respectively) impaired by economic and 'ecological' considerations. Neutrino and muon physics in the multi-TeV range would appear not to be an option for these machines. We partially reverse this conclusion by estimating the characteristics of the 'prompt' νsub(μ), νsub(e), νsub(tau) and μ beams necessarily produced (for free) at the pp or anti pp intersections. The neutrino beams from a high luminosity (pp) collider are not much less intense than the neutrino beam from the collider's dump, but require no muon shielding. The muon beams from the same intersections are intense and energetic enough to study μp and μN interactions with considerable statistics and a Q 2 -coverage well beyond the presently available one. The physics program allowed by these lepton beams is a strong advocate of machines with the highest possible luminosity: pp (not anti pp) colliders. (orig.)

Renormalization theory of beam-beam interaction in electron-positron colliders

International Nuclear Information System (INIS)

Chin, Y.H.

1989-07-01

This note is devoted to explaining the essence of the renormalization theory of beam-beam interaction for carrying out analytical calculations of equilibrium particle distributions in electron-positron colliding beam storage rings. Some new numerical examples are presented such as for betatron tune dependence of the rms beam size. The theory shows reasonably good agreements with the results of computer simulations. 5 refs., 6 figs

PREVENTING POLLUTION USING ISO 14001 AT A PARTICLE ACCELERATOR THE RELATIVISTIC HEAVY ION COLLIDER PROJECT

International Nuclear Information System (INIS)

BRIGGS, S.L.K.; MUSOLINO, S.V.

2001-01-01

In early 1997 Brookhaven National Laboratory (BNL) discovered that the spent fuel pool of their High Flux Beam Reactor was leaking tritium into the groundwater. Community members, activist groups, politicians and regulators were outraged with the poor environmental management practices at BNL. The reactor was shut down and the Department of Energy (DOE) terminated the contract with the existing Management Company. At this same time, a major new scientific facility, the Relativistic Heavy Ion Collider (RHIC), was nearing the end of construction and readying for commissioning. Although environmental considerations had been incorporated into the design of the facility; some interested parties were skeptical that this new facility would not cause significant environmental impacts. RHIC management recognized that the future of its operation was dependent on preventing pollution and allaying concerns of its stakeholders. Although never done at a DOE National Laboratory before Brookhaven Science Associates, the new management firm, committed to implementing an Environmental Management System (EMS) and RHIC managers volunteered to deploy it within their facility on an extremely aggressive schedule. Several of these IS0 requirements contribute directly to preventing pollution, an area where particular emphasis was placed. This paper describes how Brookhaven used the following key IS0 14001 elements to institutionalize Pollution Prevention concepts: Environmental Policy, Aspects, Objectives and Targets, Environmental Management Program, Structure and Responsibility, Operational Controls, Training, and Management Review. In addition, examples of implementation at the RHIC Project illustrate how BNL's premiere facility was able to demonstrate to interested parties that care had been taken to implement technological and administrative controls to minimize environmental impacts, while at the same time reduce the applicability of regulatory requirements to their operations

The muon collider (Sandro's snake)

International Nuclear Information System (INIS)

Ruggiero, A.G.

1992-01-01

This paper describes a feasibility study for the design of a muon collider. Recognized the fact that the particle lifetime increases linearly with the energy, we have adopted a scheme where steps of cooling and acceleration are entwined. We have indeed found convenient to accelerate the beam as fast as possible to increase its chances of survival, and necessary to dilute the action of cooling throughout the entire accelerating process to make it more effective and affordable. All acceleration and cooling steps are executed in a single pass essentially along a curvilinear and open path. We do not believe it is possible to handle the beam otherwise in circular and closed rings, as it has been proposed in the past. The example shown in this paper describes a muon collider at the energy of 250 GeV per beam and a luminosity of 4 x 10 28 cm -2 s -1 . We have adopted an extrapolation of the stochastic cooling method for the reduction of the beam emittance

Violent collisions of spinning protons

Energy Technology Data Exchange (ETDEWEB)

Krisch, A.D. [Michigan Univ., Spin Physics Center, Ann Arbor, MI (United States)

2005-07-01

The author draws the history of polarized proton beams that has relied on experiments that took place in different accelerators like ZGS (zero gradient synchrotron, Argonne), AGS (Brookhaven) and Fermilab from 1973 till today. The first studies of the behavior and spin-manipulation of polarized protons helped in developing polarized beams around the world: Brookhaven now has 200 GeV polarized protons in the RHIC collider, perhaps someday the 7 TeV LHC at CERN might have polarized protons.

Flat beams in a 50 TeV hadron collider

International Nuclear Information System (INIS)

Peggs, S.; Harrison, M.; Pilat, F.; Syphers, M.

1997-01-01

The basic beam dynamics of a next generation 50 x 50 TeV hadron collider based on a high field magnet approach have been outlined over the past several years. Radiation damping not only produces small emittances, but also flat beams, just as in electron machines. Based on open-quotes Snowmass 96close quotes parameters, we investigate the issues associated with flat beams in very high energy hadron colliders

Colliding druthers

International Nuclear Information System (INIS)

Ankenbrandt, C.; Johnson, R.P.

1977-01-01

Recommendations are made to maximize the usefulness of the colliding beam facility of the Main Ring and Energy Doubler at the Fermilab accelerator. The advantages of the transposed crossing geometry over the kissing geometry are pointed out

CLIC accelerator modules under construction at CERN

CERN Multimedia

Anna Pantelia

2012-01-01

The Compact LInear Collider (CLIC) study is dedicated to the design of an electron-positron (e- e+) linear accelerator, colliding particle beams at the energy of 3 TeV. The CLIC required luminosity can be reached with powerful particle beams (14 MW each) colliding with extremely small dimensions and high beam stability at the interaction point. The accelerated particle beams must have dimensions of 45 nm in the horizontal plane and 1 nm in the vertical plane. CLIC relies upon a novel two-beam acceleration concept in which the Radio Frequency (RF) power is extracted from a low energy but high-intensity particle beam, called Drive Beam (DB), and transferred to a parallel high energy accelerating particle beam, called Main Beam (MB). The extraction and transfer of the RF power is achieved by the Power Extraction and Transfer Structures (PETS) and the particle beam acceleration is achieved with high precision RF-Accelerating Structures (AS), operating at 11.9942 GHz with an accelerating gradient of 100 MV/m, whi...

Heavy ion acceleration at the AGS

International Nuclear Information System (INIS)

Lee, Y.Y.

1989-01-01

The Brookhaven AGS is alternating gradient synchrotron, 807 meters in circumference, which was originally designed for only protons. Using the 15 MV Brookhaven Tandem Van de Graaff as an injector, the AGS started to accelerate heavy ions of mass lighter than sulfur. Because of the relatively poor vacuum (∼10 -8 Torr), the AGS is not able to accelerate heavier ions which could not be fully stripped of electrons at the Tandem energy. When the AGS Booster, which is under construction, is completed the operation will be extended to all species of heavy ions including gold and uranium. Because ultra-high vacuum (∼10 -11 Torr) is planned, the Booster can accelerate partially stripped elements. The operational experience, the parameters, and scheme of heavy ion acceleration will be presented in detail from injection to extraction, as well as future injection into the new Relativistic Heavy Ion Collider (RHIC). A future plan to improve intensity of the accelerator will also be presented. 5 figs., 4 tabs

Accelerator Physics Challenges for Future Linear Colliders

Energy Technology Data Exchange (ETDEWEB)

Raubenheimer, Tor O

1999-08-09

At the present time, there are a number of future linear collider designs with a center-of-mass energy of 500 GeV or more with luminosities in excess of 10{sup -34}cm{sup -2}s{sup -1} . Many of these designs are at an advanced state of development. However, to attain the high luminosity, the colliders require very small beam emittances, strong focusing, and very good stability. In this paper, some of the outstanding issues related to producing and maintaining the small beam sizes are discussed. Although the different designs are based on very different rf technologies, many of these problems are common.

Cost-Benefit Analysis of the Large Hadron Collider to 2025 and beyond

CERN Document Server

Florio, Massimo; Sirtori, Emanuela

2015-01-01

Social cost-benefit analysis (CBA) of projects has been successfully applied in different fields such as transport, energy, health, education, and environment, including climate change. It is often argued that it is impossible to extend the CBA approach to the evaluation of the social impact of research infrastructures, because the final benefit to society of scientific discovery is generally unpredictable. Here, we propose a quantitative approach to this problem, we use it to design an empirically testable CBA model, and we apply it to the the Large Hadron Collider (LHC), the highest-energy accelerator in the world, currently operating at CERN. We show that the evaluation of benefits can be made quantitative by determining their value to users (scientists, early-stage researchers, firms, visitors) and non-users (the general public). Four classes of contributions to users are identified: knowledge output, human capital development, technological spillovers, and cultural effects. Benefits for non-users can be ...

Future Circular Collider Study FCC-he Baseline Parameters

CERN Document Server

Bruning, Oliver; Klein, Max; Pellegrini, Dario; Schulte, Daniel; Zimmermann, Frank

2017-01-01

Initial considerations are presented on the FCC-he, the electron-hadron collider con guration within the Future Circular Collider study. This note considers arguments for the choice of the electron beam energy based on physics, ep scattering kinematics and cost. The default con guration for the electron accelerator, as for the LHeC, is chosen to be a multi-turn energy recovery linac external to the proton beam tunnel. The main accelerator parameters of the FCC-he are discussed, assuming the concurrent operation of ep with the 100TeV cms energy pp collider. These are compared with the LHeC design concept, for increased performance as for a Higgs facility using the HL-LHC, and also the high energy HE-LHC ep collider configuration. Initial estimates are also provided for the luminosity performance of electron-ion colliders for the 60 GeV electron ERL when combined with the LHC, the HE-LHC and the FCC ion beams.

Linear Colliders TESLA

International Nuclear Information System (INIS)

Anon.

1994-01-01

The aim of the TESLA (TeV Superconducting Linear Accelerator) collaboration (at present 19 institutions from seven countries) is to establish the technology for a high energy electron-positron linear collider using superconducting radiofrequency cavities to accelerate its beams. Another basic goal is to demonstrate that such a collider can meet its performance goals in a cost effective manner. For this the TESLA collaboration is preparing a 500 MeV superconducting linear test accelerator at the DESY Laboratory in Hamburg. This TTF (TESLA Test Facility) consists of four cryomodules, each approximately 12 m long and containing eight 9-cell solid niobium cavities operating at a frequency of 1.3 GHz

Higher-order-mode absorbers for energy recovery linac cryomodules at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Hahn, H.; Ben-Zvi, I.; Calaga, R.; Hammons, L.; Johnson, E.C.; Kewisch, J.; Litvinenko, V.N.; Xu, W.

2010-01-01

Several future accelerator projects at Brookhaven for the Relativistic Heavy Ion Collider (RHIC) are based on energy recovery linacs (ERLs) with high-charge high-current electron beams. Their stable operation mandates effective higher-order-mode (HOM) damping. The development of HOM dampers for these projects is pursued actively at this laboratory. Strong HOM damping was experimentally demonstrated both at room and at superconducting (SC) temperatures in a prototype research and development (R and D) five-cell niobium superconducting rf (SRF) cavity with ferrite dampers. Two room-temperature mock-up five-cell copper cavities were used to study various damper configurations with emphasis on capacitive antenna dampers. An innovative type of ferrite damper over a ceramic break for an R and D SRF electron gun also was developed. For future SRF linacs longer cryomodules comprised of multiple superconducting cavities with reasonably short intercavity transitions are planned. In such a configuration, the dampers, located closer to the cavities, will be at cryogenic temperatures; this will impose additional constraints and complications. This paper presents the results of simulations and measurements of several damper configurations.

Higher-order-mode absorbers for energy recovery linac cryomodules at Brookhaven National Laboratory

Science.gov (United States)

Hahn, H.; Ben-Zvi, I.; Calaga, R.; Hammons, L.; Johnson, E. C.; Kewisch, J.; Litvinenko, V. N.; Xu, Wencan

2010-12-01

Several future accelerator projects at Brookhaven for the Relativistic Heavy Ion Collider (RHIC) are based on energy recovery linacs (ERLs) with high-charge high-current electron beams. Their stable operation mandates effective higher-order-mode (HOM) damping. The development of HOM dampers for these projects is pursued actively at this laboratory. Strong HOM damping was experimentally demonstrated both at room and at superconducting (SC) temperatures in a prototype research and development (R&D) five-cell niobium superconducting rf (SRF) cavity with ferrite dampers. Two room-temperature mock-up five-cell copper cavities were used to study various damper configurations with emphasis on capacitive antenna dampers. An innovative type of ferrite damper over a ceramic break for an R&D SRF electron gun also was developed. For future SRF linacs longer cryomodules comprised of multiple superconducting cavities with reasonably short intercavity transitions are planned. In such a configuration, the dampers, located closer to the cavities, will be at cryogenic temperatures; this will impose additional constraints and complications. This paper presents the results of simulations and measurements of several damper configurations.

Higher-order-mode absorbers for energy recovery linac cryomodules at Brookhaven National Laboratory

Directory of Open Access Journals (Sweden)

H. Hahn

2010-12-01

Full Text Available Several future accelerator projects at Brookhaven for the Relativistic Heavy Ion Collider (RHIC are based on energy recovery linacs (ERLs with high-charge high-current electron beams. Their stable operation mandates effective higher-order-mode (HOM damping. The development of HOM dampers for these projects is pursued actively at this laboratory. Strong HOM damping was experimentally demonstrated both at room and at superconducting (SC temperatures in a prototype research and development (R&D five-cell niobium superconducting rf (SRF cavity with ferrite dampers. Two room-temperature mock-up five-cell copper cavities were used to study various damper configurations with emphasis on capacitive antenna dampers. An innovative type of ferrite damper over a ceramic break for an R&D SRF electron gun also was developed. For future SRF linacs longer cryomodules comprised of multiple superconducting cavities with reasonably short intercavity transitions are planned. In such a configuration, the dampers, located closer to the cavities, will be at cryogenic temperatures; this will impose additional constraints and complications. This paper presents the results of simulations and measurements of several damper configurations.

Determination of Beam Intensity and Position in a Particle Accelerator

CERN Document Server

Kasprowicz, Grzegorz; Raich, Uli

2011-10-04

A subject of the thesis is conception, design, implementation, tests and deployment of new position measurement system of particle bunch in the CERN PS circular accelerator. The system is based on novel algorithms of particle position determination. The Proton Synchrotron accelerator (PS), installed at CERN†, although commissioned in 1959, still plays a central role in the production of beams for the Antiproton Decelerator, Super Proton Synchrotron, various experimental areas and for the Large Hadron Collider (LHC)‡. The PS produces beams of different types of particles, mainly protons, but also various species of ions. Almost all these particle beams pass through the PS. The quality of the beams delivered to the LHC has a direct impact on the effective luminosity, and therefore the performance of the instrumentation of the PS is of great importance. The old trajectory and orbit measurement system of the PS is dated back to 1988 and no longer fulfilled present day requirements. It used 40 beam posi...

Determination of beam intensity and position in a particle accelerator

CERN Document Server

Kasprowicz, G

2011-01-01

A subject of the thesis is conception, design, implementation, tests and deployment of new position measurement system of particle bunch in the CERN PS circular accelerator. The system is based on novel algorithms of particle position determination. The Proton Synchrotron accelerator (PS), installed at CERN, although commissioned in 1959, still plays a central role in the production of beams for the Antiproton Decelerator, Super Proton Synchrotron, various experimental areas and for the Large Hadron Collider (LHC). The PS produces beams of different types of particles, mainly protons, but also various species of ions. Almost all these particle beams pass through the PS. The quality of the beams delivered to the LHC has a direct impact on the effective luminosity, and therefore the performance of the instrumentation of the PS is of great importance. The old trajectory and orbit measurement system of the PS is dated back to 1988 and no longer fulfilled present day requirements. It used 40 beam position monitors...

Multibunch beam breakup in high energy linear colliders

International Nuclear Information System (INIS)

Thompson, K.A.; Ruth, R.D.

1989-03-01

The SLAC design for a next-generation linear collider with center-of-mass energy of 0.5 to 1.0 TeV requires that multiple bunches (/approximately/10) be accelerated on each rf fill. At the beam intensity (/approximately/10 10 particles per bunch) and rf frequency (11--17 GHz) required, the beam would be highly unstable transversely. Using computer simulation and analytic models, we have studied several possible methods of controlling the transverse instability: using damped cavities to damp the transverse dipole modes; adjusting the frequency of the dominant transverse mode relative to the rf frequency, so that bunches are placed near zero crossings of the wake; introducing a cell-to-cell spread in the transverse dipole mode frequencies; and introducing a bunch-to-bunch variation in the transverse focusing. The best cure(s) to use depend on the bunch spacing, intensity, and other features of the final design. 8 refs., 3 figs

The first picosecond terawatt CO2 laser at the Brookhaven Accelerator Test Facility

International Nuclear Information System (INIS)

Pogorelsky, I.V.; Ben-Zvi, I.; Babzien, M.

1998-02-01

The first terawatt picosecond CO 2 laser will be brought to operation at the Brookhaven Accelerator Test Facility in 1998. System consists of a single-mode TEA oscillator, picosecond semiconductor optical switch, multi-atmosphere. The authors report on design, simulation, and performance tests of the 10 atm final amplifier that allows for direct multi-joule energy extraction in a picosecond laser pulse

A positron beam for the linear collider scheme of a B-meson factory

International Nuclear Information System (INIS)

Chehab, R.

1988-02-01

An approach for a conventional positron source intended to a BantiB linear collider scheme is here given. Optical matching devices between the source and the accelerator are considered and some comparisons are made regarding the maximum acceptance and the positron beam qualities. Focusing in the preaccelerator and in the main linac are also considered. Heating and radiation problems which may introduce severe limitations are only partly examined

The International Linear Collider Technical Design Report - Volume 3.II: Accelerator Baseline Design

Energy Technology Data Exchange (ETDEWEB)

Adolphsen, Chris [SLAC National Accelerator Lab., Menlo Park, CA (United States); et al.

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.

The heavy ion injection scheme for RHIC [Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Rhoades-Brown, M.J.

1989-01-01

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven has a multi-component injection system. The Collider requires very heavy ions such as 79 197 Au to be injected fully stripped of atomic electrons, at a kinetic energy of approximately 10 GeV/nucleon. However, the heavy ions are produced initially at a negative ion source and accelerated first in a 15 MV Tandem. These partially stripped ions have a kinetic energy of approximately 1 MeV/nucleon on leaving the Tandem. In order to achieve the injection requirements for RHIC, the partially stripped ions are accelerated in the Booster (currently under construction) and pass through a stripping foil on their way to the Alternating Gradient Synchrotron (AGS), where they are further accelerated before injection into RHIC. Recent theoretical calculations have shown quite convincingly that very heavy ions with 2 electrons in the filled K-shell may be accelerated with negligible loss in the AGS. 13 refs., 3 figs., 3 tabs

Status and plans of the Compact Linear Collider Study

CERN Document Server

Doebert, Steffen

2016-01-01

The Compact Linear Collider (CLIC) project is exploring the possibility of constructing a multiTeV linear electron-positron collider for high-energy frontier physics studies beyond the LHC era. The CLIC concept is based on high-gradient normal-conducting accelerating structures. The RF power for the acceleration of the colliding beams is produced by a two-beam acceleration scheme, where power is extracted from a high current drive beam that runs parallel with the main linac. The key ongoing studies involve accelerator parameter optimisation, technical studies and component development, alignment and stability, and include a number of system performance studies in test-facilities around the world. The CLIC physics potential and main detector issues, as well as possible implementation staging, are being studied in parallel. A summary of the progress and status of the corresponding studies will be given, as well as an outline of the preparation and work towards developing a CLIC implementation plan by 2018/19

Brookhaven four-stage accel-decel production of low-energy highly stripped heavy ions

International Nuclear Information System (INIS)

Barrette, J.; Thieberger, P.

1981-01-01

The dual MP tandem facility at Brookhaven has been used in a four-stage accel-decel mode to produce highly stripped S ion beams (Q = 10-16 + ). Fully stripped S ions were obtained at energies down to 8 MeV. The low energy limit is presently due to the inclined field configuration of the last acceleration tube

SuperB Progress Report for Accelerator

Energy Technology Data Exchange (ETDEWEB)

Biagini, M.E.; Boni, R.; Boscolo, M.; Buonomo, B.; Demma, T.; Drago, A.; Esposito, M.; Guiducci, S.; Mazzitelli, G.; Pellegrino, L.; Preger, M.A.; Raimondi, P.; Ricci, R.; Rotundo, U.; Sanelli, C.; Serio, M.; Stella, A.; Tomassini, S.; Zobov, M.; /Frascati; Bertsche, K.; Brachman, A.; /SLAC /Novosibirsk, IYF /INFN, Pisa /Pisa U. /Orsay, LAL /Annecy, LAPP /LPSC, Grenoble /IRFU, SPP, Saclay /DESY /Cockroft Inst. Accel. Sci. Tech. /U. Liverpool /CERN

2012-02-14

This report details the progress made in by the SuperB Project in the area of the Collider since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008. With this document we propose a new electron positron colliding beam accelerator to be built in Italy to study flavor physics in the B-meson system at an energy of 10 GeV in the center-of-mass. This facility is called a high luminosity B-factory with a project name 'SuperB'. This project builds on a long history of successful e+e- colliders built around the world, as illustrated in Figure 1.1. The key advances in the design of this accelerator come from recent successes at the DAFNE collider at INFN in Frascati, Italy, at PEP-II at SLAC in California, USA, and at KEKB at KEK in Tsukuba Japan, and from new concepts in beam manipulation at the interaction region (IP) called 'crab waist'. This new collider comprises of two colliding beam rings, one at 4.2 GeV and one at 6.7 GeV, a common interaction region, a new injection system at full beam energies, and one of the two beams longitudinally polarized at the IP. Most of the new accelerator techniques needed for this collider have been achieved at other recently completed accelerators including the new PETRA-3 light source at DESY in Hamburg (Germany) and the upgraded DAFNE collider at the INFN laboratory at Frascati (Italy), or during design studies of CLIC or the International Linear Collider (ILC). The project is to be designed and constructed by a worldwide collaboration of accelerator and engineering staff along with ties to industry. To save significant construction costs, many components from the PEP-II collider at SLAC will be recycled and used in this new accelerator. The interaction region will be designed in collaboration with the particle physics detector to guarantee successful mutual use. The accelerator collaboration will consist of several groups at present

Conceptual design of the Relativistic Heavy Ion Collider: RHIC

International Nuclear Information System (INIS)

1986-05-01

The complete Relativistic Heavy Ion Collider (RHIC) facility will be a complex set of accelerators and beam transfer equipment connecting them. A significant portion of the total facility either exists or is under construction. Two existing Tandem Van de Graaff accelerators will serve for the initial ion acceleration. Ions with a charge of -1 would be accelerated from ground to +15 MV potential, pass through a stripping foil, and accelerate back to ground potential, where they would pass through a second stripping foil. From there the ions will traverse a long transfer line to the AGS tunnel and be injected into the Booster accelerator. The Booster accelerates the ion bunch, and then the ions pass through one more stripper and then enter the Alternating Gradient Synchrotron (AGS), where they are accelerated to the top AGS energy and transferred to the collider. Bending and focusing of ion beams is to be achieved by superconducting magnets. The physics goals behind the RHIC are enumerated, particularly as regards the study of quark matter and the characteristics of high energy nucleus-nucleus collisions. The design of the collider and all its components is described, including the injector, the lattice, magnet system, cryogenic and vacuum systems, beam transfer, injection, and dump, rf system, and beam instrumentation and control system. Also given are cost estimates, construction schedules, and a management plan

Beams at U.S. high energy physics laboratories

International Nuclear Information System (INIS)

1976-06-01

Tables are given of beam characteristics for particle accelerators at Argonne National Laboratory, Brookhaven National Laboratory, Cornell University, Fermi National Accelerator Laboratory, and the Stanford Linear Accelerator Center. Characteristics given include energy, momentum, and flux

Status and future directions for advanced accelerator research - conventional and non-conventional collider concepts

International Nuclear Information System (INIS)

Siemann, R.H.

1997-01-01

The relationship between advanced accelerator research and future directions for particle physics is discussed. Comments are made about accelerator research trends in hadron colliders, muon colliders, and e + 3 - linear colliders

A Novel Method and Error Analysis for Beam Optics Measurements and Corrections at the Large Hadron Collider

CERN Document Server

Langner, Andy Sven; Rossbach, Jörg; Tomás, Rogelio

2017-02-17

The Large Hadron Collider (LHC) is currently the world's largest particle accelerator with the highest center of mass energy in particle collision experiments. The control of the particle beam focusing is essential for the performance reach of such an accelerator. For the characterization of the focusing properties at the LHC, turn-by-turn beam position data is simultaneously recorded at numerous measurement devices (BPMs) along the accelerator, while an oscillation is excited on the beam. A novel analysis method for these measurements ($N$-BPM method) is developed here, which is based on a detailed analysis of systematic and statistical error sources and their correlations. It has been applied during the commissioning of the LHC for operation at an unprecedented energy of 6.5 TeV. In this process a stronger focusing than its design specifications has been achieved. This results in smaller transverse beam sizes at the collision points and allows for a higher rate of particle collisions. For the derivation of ...

Polarized muon beams for muon collider

Energy Technology Data Exchange (ETDEWEB)

Skrinsky, A.N. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki

1996-11-01

An option for the production of intense and highly polarized muon beams, suitable for a high-luminosity muon collider, is described briefly. It is based on a multi-channel pion-collection system, narrow-band pion-to-muon decay channels, proper muon spin gymnastics, and ionization cooling to combine all of the muon beams into a single bunch of ultimately low emittance. (orig.).

ACE3P Computations of Wakefield Coupling in the CLIC Two-Beam Accelerator

International Nuclear Information System (INIS)

Candel, Arno

2010-01-01

The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its novel two-beam accelerator concept envisions rf power transfer to the accelerating structures from a separate high-current decelerator beam line consisting of power extraction and transfer structures (PETS). It is critical to numerically verify the fundamental and higher-order mode properties in and between the two beam lines with high accuracy and confidence. To solve these large-scale problems, SLAC's parallel finite element electromagnetic code suite ACE3P is employed. Using curvilinear conformal meshes and higher-order finite element vector basis functions, unprecedented accuracy and computational efficiency are achieved, enabling high-fidelity modeling of complex detuned structures such as the CLIC TD24 accelerating structure. In this paper, time-domain simulations of wakefield coupling effects in the combined system of PETS and the TD24 structures are presented. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel CLIC two-beam accelerator scheme.

Short-lived radionuclide production capability at the Brookhaven Linac Isotope Producer

International Nuclear Information System (INIS)

Mausner, L.F.; Richards, P.

1985-01-01

The Brookhaven National Linac Isotope Producer is the first facility to demonstrate the capability of a large linear accelerator for efficient and economical production of difficult-to-make, medically useful radionuclides. The linac provides a beam of 200-MeV protons at an integrated beam current of up to 60 μA. The 200-MeV proton energy is very suitable for isotope production because the spallation process can create radionuclides unavailable at lower energy accelerators or reactors. Several medically important short-lived radionuclides are presently being prepared for on-site and off-site collaborative research programs. These are iodine-123, iron-52, manganese-52m, ruthenium-97, and the rubidium-81-krypton-81m system. The production parameters for these are summarized

Multi-MW accelerator target material properties under proton irradiation at Brookhaven National Laboratory linear isotope producer

Science.gov (United States)

Simos, N.; Ludewig, H.; Kirk, H.; Dooryhee, E.; Ghose, S.; Zhong, Z.; Zhong, H.; Makimura, S.; Yoshimura, K.; Bennett, J. R. J.; Kotsinas, G.; Kotsina, Z.; McDonald, K. T.

2018-05-01

The effects of proton beams irradiating materials considered for targets in high-power accelerator experiments have been studied using the Brookhaven National Laboratory's (BNL) 200 MeV proton linac. A wide array of materials and alloys covering a wide range of the atomic number (Z) are being scoped by the high-power accelerator community prompting the BNL studies to focus on materials representing each distinct range, i.e. low-Z, mid-Z and high-Z. The low range includes materials such as beryllium and graphite, the midrange alloys such as Ti-6Al-4V, gum metal and super-Invar and finally the high-Z range pure tungsten and tantalum. Of interest in assessing proton irradiation effects are (a) changes in physiomechanical properties which are important in maintaining high-power target functionality, (b) identification of possible limits of proton flux or fluence above which certain materials cease to maintain integrity, (c) the role of material operating temperature in inducing or maintaining radiation damage reversal, and (d) phase stability and microstructural changes. The paper presents excerpt results deduced from macroscopic and microscopic post-irradiation evaluation (PIE) following several irradiation campaigns conducted at the BNL 200 MeV linac and specifically at the isotope producer beam-line/target station. The microscopic PIE relied on high energy x-ray diffraction at the BNL NSLS X17B1 and NSLS II XPD beam lines. The studies reveal the dramatic effects of irradiation on phase stability in several of the materials, changes in physical properties and ductility loss as well as thermally induced radiation damage reversal in graphite and alloys such as super-Invar.

The magnet system of the Relativistic Heavy Ion Collider (RHIC)

International Nuclear Information System (INIS)

Greene, A.; Anerella, M.; Cozzolino, J.

1995-01-01

The Relativistic Heavy Ion Collider now under construction at Brookhaven National Laboratory (BNL) is a colliding ring accelerator to be completed in 1999. Through collisions of heavy ions it is hoped to observe the creation of matter at extremely high temperatures and densities, similar to what may have occurred in the original ''Big Bang.'' The collider rings will consist of 1740 superconducting magnet elements. Some of elements are being manufactured by industrial partners (Northrop Grumman and Everson Electric). Others are being constructed or assembled at BNL. A description is given of the magnet designs, the plan for manufacturing and test results. In the manufacturing of the magnets, emphasis has been placed on uniformity of their performance and on quality. Results so far indicate that this emphasis has been very successful

Study for a failsafe trigger generation system for the Large Hadron Collider beam dump kicker magnets

CERN Document Server

Rampl, M

1999-01-01

The 27 km-particle accelerator Large Hadron Collider (LHC), which will be completed at the European Laboratory for Particle Physics (CERN) in 2005, will work with extremely high beam energies (~334 MJ per beam). Since the equipment and in particular the superconducting magnets must be protected from damage caused by these high energy beams the beam dump must be able to absorb this energy very reliable at every stage of operation. The kicker magnets that extract the particles from the accelerator are synchronised with the beam by the trigger generation system. This thesis is a first study for this electronic module and its functions. A special synchronisation circuit and a very reliable electronic switch were developed. Most functions were implemented in a Gate-Array to improve the reliability and to facilitate modifications during the test stage. This study also comprises the complete concept for the prototype of the trigger generation system. During all project stages reliability was always the main determin...

Hadron collider luminosity limitations

CERN Document Server

Evans, Lyndon R

1992-01-01

The three colliders operated to date have taught us a great deal about the behaviour of both bunched and debunched beams in storage rings. The main luminosity limitations are now well enough understood that most of them can be stronglu attenuated or eliminated by approriate design precautions. Experience with the beam-beam interaction in both the SPS and the Tevatron allow us to predict the performance of the new generation of colliders with some degree of confidence. One of the main challenges that the accelerator physicist faces is the problem of the dynamic aperture limitations due to the lower field quality expected, imposed by economic and other constraints.

Seismic studies for Fermilab future collider projects

International Nuclear Information System (INIS)

Lauh, J.; Shiltsev, V.

1997-11-01

Ground motion can cause significant beam emittance growth and orbit oscillations in large hadron colliders due to a vibration of numerous focusing magnets. Larger accelerator ring circumference leads to smaller revolution frequency and, e.g. for the Fermilab Very Large Hadron Collider(VLHC) 50-150 Hz vibrations are of particular interest as they are resonant with the beam betatron frequency. Seismic measurements at an existing large accelerator under operation can help to estimate the vibrations generated by the technical systems in future machines. Comparison of noisy and quiet microseismic conditions might be useful for proper choice of technical solutions for future colliders. This article presents results of wide-band seismic measurements at the Fermilab site, namely, in the tunnel of the Tevatron and on the surface nearby, and in two deep tunnels in the Illinois dolomite which is though to be a possible geological environment of the future accelerators

Brookhaven highlights

International Nuclear Information System (INIS)

Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L.

1992-01-01

This publication provides a broad overview of the research programs and efforts being conducted, built, designed, and planned at Brookhaven National Laboratory. This work covers a broad range of scientific disciplines. Major facilities include the Alternating Gradient Synchrotron (AGS), with its newly completed booster, the National Synchrotron Light Source (NSLS), the High Flux Beam Reactor (HFBR), and the RHIC, which is under construction. Departments within the laboratory include the AGS department, accelerator development, physics, chemistry, biology, NSLS, medical, nuclear energy, and interdepartmental research efforts. Research ranges from the pure sciences, in nuclear physics and high energy physics as one example, to environmental work in applied science to study climatic effects, from efforts in biology which are a component of the human genome project to the study, production, and characterization of new materials. The paper provides an overview of the laboratory operations during 1992, including staffing, research, honors, funding, and general laboratory plans for the future

Brookhaven highlights

Energy Technology Data Exchange (ETDEWEB)

Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L. (eds.)

1992-01-01

This publication provides a broad overview of the research programs and efforts being conducted, built, designed, and planned at Brookhaven National Laboratory. This work covers a broad range of scientific disciplines. Major facilities include the Alternating Gradient Synchrotron (AGS), with its newly completed booster, the National Synchrotron Light Source (NSLS), the High Flux Beam Reactor (HFBR), and the RHIC, which is under construction. Departments within the laboratory include the AGS department, accelerator development, physics, chemistry, biology, NSLS, medical, nuclear energy, and interdepartmental research efforts. Research ranges from the pure sciences, in nuclear physics and high energy physics as one example, to environmental work in applied science to study climatic effects, from efforts in biology which are a component of the human genome project to the study, production, and characterization of new materials. The paper provides an overview of the laboratory operations during 1992, including staffing, research, honors, funding, and general laboratory plans for the future.

R&D for Future Accelerators

CERN Document Server

Zimmermann, Frank

2006-01-01

Research & development for future accelerators are reviewed. First, I discuss colliding hadron beams, in particular upgrades to the Large Hadron Collider (LHC). This is followed by an overview of new concepts and technologies for lepton ring colliders, with examples taken from VEPP-2000, DAFNE-2, and Super-KEKB. I then turn to recent progress and studies for the multi-TeV Compact Linear Collider (CLIC). Some generic linear-collider research, centered at the KEK Accelerator Test Facility, is described next. Subsequently, I survey the neutrino factory R&D performed in the framework of the US feasibility study IIa, and I also comment on a novel scheme for producing monochromatic neutrinos from an electron-capture beta beam. Finally, I present innovative ideas for a high-energy muon collider and I consider recent experimental progress on laser and plasma acceleration.

Charge exchange studies with Gold ions at the Brookhaven Booster and AGS

International Nuclear Information System (INIS)

Ahrens, L.A.; Hseuh, H.C.; Roser, T.

1994-01-01

Efficient acceleration of Gold ions to ll GeV/nucleon places strong constraints on the vacuum and also on the choice of thickness and material of the necessary stripping foils. Results of a number of detailed experimental studies performed with the Gold beam at the Brookhaven Booster and AGS to determine the relevant electron stripping and pick-up probabilities are presented. Of particular interest is the lifetime of the relatively low energy, partially stripped Gold beam in the Booster and the stripping efficiency to Helium-like AU +77 for injection into the AGS

BROOKHAVEN

International Nuclear Information System (INIS)

Anon.

1993-01-01

Neutrino physics has been an integral part of the Brookhaven research programme for much of the Laboratory's 46-year history. Milestones have been the determination of the helicity of neutrinos (1958), the establishment of the existence of two kinds of neutrinos (1962) for which Leon Lederman, Mel Schwartz and Jack Steinberger were awarded the 1988 Nobel Physics Prize, the discovery of charmed baryons in the 7' Bubble Chamber in 1975, and the ongoing measurements by Ray Davis and collaborators of solar neutrinos, first reported in 1968. There have also been significant contributions to the understanding of neutral currents in exclusive hadron and electron channels. In addition some of the earliest, and to date best, accelerator limits on electron muon neutrino oscillations are from Brookhaven experiments. The Laboratory is also the 'B' in the IMB underground experiment, built to search for proton decay and which caught neutrinos from the SN 1987a supernova. At present Brookhaven is heavily involved in the Gallex project in the Gran Sasso and recently a new collaboration has received scientific approval for a long baseline experiment to search for muon neutrino oscillations via muon neutrino disappearance

A beam-based alignment technique for correction of accelerator structure misalignments

International Nuclear Information System (INIS)

Kubo, K.; Raubenheimer, T.O.

1994-08-01

This paper describes a method of reducing the transverse emittance dilution in linear colliders due to transverse wakefields arising-from misaligned accelerator structures. The technique is a generalization of the Wake-Free correction algorithm. The structure alignment errors are measured locally by varying the bunch charge and/or bunch length and measuring the change in the beam trajectory. The misalignments can then be corrected by varying the beam trajectory or moving structures. The results of simulations are presented demonstrating the viability of the technique

Ultra-relativistic heavy ions and the CBA

International Nuclear Information System (INIS)

McLerran, L.D.

1982-01-01

The study of ultra-relativistic heavy ions at an accelerator such as the CBA provides a unique glimpse of matter as it may have appeared in the early universe. This hot dense matter very probably appears as a quark-gluon plasma which expands and cools into hadronic matter. The CBA would provide data at the very highest energies, and produce matter at the highest energy densities. The possibility of using a cyclotron to inject very heavy ions into the AGS and then into the CBA would also allow the production of quark-gluon matter at higher energy densities than would light ions, and would make the matter in a larger volume where surface effects are minimized. At the highest energies with very heavy ions, there is great flexibility in the experimental signals which might be studied, as well as the nature of the matter which is produced. Some of the possibilities are discussed

High Energy Accelerator and Colliding Beam User Group

International Nuclear Information System (INIS)

Snow, G.A.; Skuja, A.

1992-05-01

This report discusses research in the following areas: the study of e + e - interactions; Hadron collider physics at Fermilab; fixed target physics and particle physics of general interest; and, the solenoidal detector collaboration at SSCL

CLIC, a Multi-TeV $e^{\\pm}$ Linear Collider

CERN Document Server

Delahaye, J P; Bossart, Rudolf; Braun, Hans Heinrich; Carron, G; Coosemans, Williame; Corsini, R; D'Amico, T E; Godot, J C; Guignard, Gilbert; Hutchins, S; Jensen, E; Millich, Antonio; Pearce, P; Potier, J P; Riche, A J; Rinolfi, Louis; Schulte, Daniel; Suberlucq, Guy; Thorndahl, L; Valentini, M; Wuensch, Walter; Zimmermann, Frank; Napoly, O; Raubenheimer, T O; Ruth, Ronald D; Syratchev, I V

1999-01-01

The CLIC study of a high energy (0.5 - 5 TeV), high luminosity (1034 - 1035 cm-2 sec-1) e± linear collider is presented. Beam acceleration using high frequency (30 GHz) normal-conducting structures operating at high accelerating fields (150 MV/m) significantly reduces the length and, in consequence, the cost of the linac. Based on new beam and linac parameters derived from a recently developed set of general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. A new cost-effective and efficient drive beam generation scheme for RF power production by the so-called "Two Beam Acceleration (TBA)" method is described. It uses a thermionic gun and a fully-loaded normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches, and RF multiplication by funnelling in compressor rings to produce the desired bunch structure. Recent 30 GHz hardware developments and ...

A multi-TeV compact $e^{+} e^{-}$ linear collider

CERN Document Server

Wilson, Ian H

2000-01-01

The CLIC study of a high energy (0.5-5 TeV), high luminosity (10/sup 34/-10/sup 35/ cm/sup -2/ sec/sup -1/) e/sup +or-/ linear collider is presented. Beam acceleration using high frequency (30 GHz) normal- conducting structures operating at high accelerating fields (150 MV /m) significantly reduces the length and, in consequence, the cost of the linac. Based on new beam and linac parameters derived from a recently developed set of general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. The drive beam generation scheme for RF power production by the so-called "Two Beam Acceleration (TBA)" method is described. It uses a thermionic gun and a fully-loaded normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches, and RF multiplication by funnelling in compressor rings to produce the desired bunch structure. Recent 30 GHz hardware developments and r...

Initial operation of the Tevatron collider

International Nuclear Information System (INIS)

Johnson, R.

1987-03-01

The Tevatron is now the highest energy proton synchrotron and the only accelerator made with superconducting magnets. Operating since 1983 as a fixed-target machine at energies up to 800 GeV, it has now been modified to operate as a 900 GeV antiproton-proton collider. This paper describes the initial operation of the machine in this mode. The new features of the Fermilab complex, including the antiproton source and the Main Ring injector with its two overpasses and new rf requirements, are discussed. Beam characteristics in the Tevatron (including lifetimes, emittances, luminosity, beam-beam tune shifts, backgrounds, and low beta complications), the coordination of the steps in the accelerator chain, and the commissioning history are also discussed. Finally, some plans for the improvement of the collider are presented

Workshop: Keeping track of particle beams

International Nuclear Information System (INIS)

Anon.

1990-01-01

How to monitor the beam in a particle accelerator - to measure beam position, intensity, profile, transverse and longitudinal emittance, and losses - was the topic of the first US National Workshop on Accelerator Instrumentation, at Brookhaven in October. Sponsored by the US Department of Energy, the meeting drew more than a hundred physicists and engineers from other national labs and from industry

Workshop: Keeping track of particle beams

Energy Technology Data Exchange (ETDEWEB)

Anon.

1990-01-15

How to monitor the beam in a particle accelerator - to measure beam position, intensity, profile, transverse and longitudinal emittance, and losses - was the topic of the first US National Workshop on Accelerator Instrumentation, at Brookhaven in October. Sponsored by the US Department of Energy, the meeting drew more than a hundred physicists and engineers from other national labs and from industry.

Beam Optics for FCC-ee Collider Ring

CERN Document Server

Oide, Katsunobu; Aumon, S; Benedikt, M; Blondel, A; Bogomyagkov, A V; Boscolo, M; Burkhardt, H; Cai, Y; Doblhammer, A; Haerer, B; Holzer, B; Koop, I; Koratzinos, M; Jowett, John M; Levichev, E B; Medina, L; Ohmi, K; Papaphilippou, Y; Piminov, P A; Shatilov, D N; Sinyatkin, S V; Sullivan, M; Wenninger, J; Wienands, U; Zhou, D; Zimmermann, F

2017-01-01

A beam optics scheme has been designed [ 1 ] for the Future Circular Collider- e + e − (FCC-ee). The main characteristics of the design are: beam energy 45 to 175 GeV, 100 km circumference with two interaction points (IPs) per ring, horizontal crossing angle of 30 mrad at the IP and the crab-waist scheme [ 2 ] with local chromaticity correction. The crab-waist scheme is implemented within the local chromaticity correction system without additional sextupoles, by reducing the strength of one of the two sextupoles for vertical chromatic correction at each side of the IP. So- called “tapering" of the magnets is applied, which scales all fields of the magnets according to the local beam energy to compensate for the effect of synchrotron radiation (SR) loss along the ring. An asymmetric layout near the interaction region reduces the critical energy of SR photons on the incoming side of the IP to values below 100 keV, while matching the geometry to the beam line of the FCC proton collider (FCC-hh) [ 3 ] as clos...

High Energy Accelerator and Colliding Beam User Group

Energy Technology Data Exchange (ETDEWEB)

Snow, G.A.; Skuja, A.

1992-05-01

This report discusses research in the following areas: the study of e{sup +}e{sup {minus}} interactions; Hadron collider physics at Fermilab; fixed target physics and particle physics of general interest; and, the solenoidal detector collaboration at SSCL.

Particle beam accelerator

International Nuclear Information System (INIS)

Turner, N.L.

1982-01-01

A particle beam accelerator is described which has several electrodes that are selectively short circuited together synchronously with changes in the magnitude of a DC voltage applied to the accelerator. By this method a substantially constant voltage gradient is maintained along the length of the unshortened electrodes despite variations in the energy applied to the beam by the accelerator. The invention has particular application to accelerating ion beams that are implanted into semiconductor wafers. (U.K.)

Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-Gradient Accelerating Structures

CERN Document Server

Tecker, F; Kelisani, M; Doebert, S; Grudiev, A; Quirante, J; Riddone, G; Syratchev, I; Wuensch, W; Kononenko, O; Solodko, A; Lebet, S

2013-01-01

RF breakdown is a key issue for the multi-TeV highluminosity e+e- Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

Long-range beam-beam experiments in the relativistic heavy ion collider

International Nuclear Information System (INIS)

Calaga, R; Fischer, W; Milas, N; Robert-Demolaize, G

2014-01-01

Long-range beam-beam effects are a potential limit to the LHC performance with the nominal design parameters, and certain upgrade scenarios under discussion. To mitigate long-range effects, current carrying wires parallel to the beam were proposed and space is reserved in the LHC for such wires. Two current carrying wires were installed in RHIC to study the effect of strong long-range beam-beam effects in a collider, as well as test the compensation of a single long-range interaction. The experimental data were used to benchmark simulations. We summarize this work

SuperB: Next-Generation e+e− B-factory Collider

CERN Document Server

Novokhatski, A; Chao, A; Nosochkov, Y; Seeman, J T; Sullivan, M K; Wienands, J T; Wittmer, W; Baylac, M A; Bourrion, O; Monseu, N; Vescovi, C; Bettoni, S; Biagini, M E; Boni, R; Boscolo, M; Demma, T; Drago, A; Esposito, M; Guiducci, S; Preger, M A; Raimondi, P; Tomassini, S; Zobov, M; Bogomyagkov, A V; Nikitin, S A; Piminov, P A; Shatilov, D N; Sinyatkin, S V; Vobly, P; Bolzon, B; Brunetti, L; Jeremie, A; A. Chancé; Fabbricatore, P; Farinon, S; Musenich, R; Liuzzo, S M; Paoloni, E; Okunev, I N; Poirier, F; Rimbault, C; Variola, A

2011-01-01

The SuperB international team continues to optimize the design of an electron-positron collider, which will allow the enhanced study of the origins of flavor physics. The project combines the best features of a linear collider (high single-collision luminosity) and a storage-ring collider (high repetition rate), bringing together all accelerator physics aspects to make a very high luminosity of 1036 cm-2 s-1. This asymmetric-energy collider with a polarized electron beam will produce hundreds of millions of B-mesons at the Y(4S) resonance. The present design is based on extremely low emittance beams colliding at a large Piwinski angle to allow very low ßy* without the need for ultra short bunches. Use of crab-waist sextupoles will enhance the luminosity, suppressing dangerous resonances and allowing for a higher beam-beam parameter. The project has flexible beam parameters, improved dynamic aperture, and spin-rotators in the Low Energy Ring for longitudinal polarization of the electron beam at the Interactio...

Observations of accelerated high current low emittance beams in the SLC Linac

International Nuclear Information System (INIS)

Seeman, J.T.; Ross, M.C.; Sheppard, J.C.; Stiening, R.F.

1985-05-01

The Linac of the SLAC Linear Collider (SLC) is required to accelerate several intense single electron and positron bunches to high energy while not enlarging their small transverse emittances. The improvements needed by the SLAC Linac to meet these goals have very stringent design criteria. As partial systems have become available, beam tests have been performed to confirm the designs. The results of those beam tests are discussed. Future plans of the improvement program are described. 13 refs., 9 figs

Beam-beam interaction in high energy linear electron-positron colliders

International Nuclear Information System (INIS)

Ritter, S.

1985-04-01

The interaction of high energy electron and positron beams in a linear collider has been investigated using a macroparticle Monte Carlo method based on a Cloud-In-Cells plasma simulation scheme. Density evolutions, luminosities, energy and angular distributions for electrons (positrons) and synchrotron photons are calculated. Beside beams with a symmetric transverse profile also flat beams are considered. A reasonably good agreement to alternative computer calculations as well as to an analytical approximation for the energy spectrum of synchrotron photons has been obtained. (author)

Generation of multi-branch beam with thermionic gun for the Japan linear collider

International Nuclear Information System (INIS)

Naito, T.; Akemoto, M.; Matsumonto, H.; Urakawa, J.; Yoshioka, M.; Akiyama, H.

1992-01-01

We report on the development of a thermionic gun that is capable of producing multi-bunch beam to be used at the KEK Accelerator Test Facility for the Japan Linear Collider project. Two types of grid pulse generators have been developed. One is an avalanche pulse generator. A Y-646E cathode was successfully operated to generate double-bunch beam with a pulse width shorter than 700 ps, bunch spacing 1.4 ns, and a peak current 4.3 A. The other grid pulse generator is a fast ECL circuit with an RF power amplifier. Generation of 20-pulse trains with 2.1 ns time spacing has been demonstrated. (Author) 4 refs., 6 figs

Photon Collider Physics with Real Photon Beams

International Nuclear Information System (INIS)

Gronberg, J; Asztalos, S

2005-01-01

Photon-photon interactions have been an important probe into fundamental particle physics. Until recently, the only way to produce photon-photon collisions was parasitically in the collision of charged particles. Recent advances in short-pulse laser technology have made it possible to consider producing high intensity, tightly focused beams of real photons through Compton scattering. A linear e + e - collider could thus be transformed into a photon-photon collider with the addition of high power lasers. In this paper they show that it is possible to make a competitive photon-photon collider experiment using the currently mothballed Stanford Linear Collider. This would produce photon-photon collisions in the GeV energy range which would allow the discovery and study of exotic heavy mesons with spin states of zero and two

Distinguishing new physics scenarios at a linear collider with polarized beams

International Nuclear Information System (INIS)

Pankov, A.A.; Tsytrinov, A.V.; Paver, N.

2006-01-01

Numerous nonstandard dynamics dominated by very high mass exchanges are described at current and future accelerator energies by appropriate contactlike effective interactions among the standard model particles. Correspondingly, they can manifest themselves only through deviations of the cross sections from the standard model predictions. If one such deviation were observed, it would be important to definitely identify, to a given confidence level, the actual source among the various possible nonstandard interactions that, in principle, can explain it. Here we estimate the identification reach on different new physics effective interactions, obtainable from angular distributions of lepton pair production processes at the planned electron-positron International Linear Collider with polarized beams. For each nonstandard model, such an identification reach defines the range in the relevant heavy mass scale parameter where it can be unambiguously distinguished from the other nonstandard models as the source of corrections to the standard model cross sections, in case these are observed. The effective interactions for which we estimate the expected identification reach are the interactions based on gravity in large extra dimensions, in TeV -1 extra dimensions and the compositeness-inspired four-fermion contact interactions. The availability of both beams polarized at the International Linear Collider turns out, in many cases, to dramatically enhance the identification sensitivity

Proceedings of the workshop on deuteron beam acceleration in the KEK 12 GeV PS

International Nuclear Information System (INIS)

Mori, Yoshiharu

1991-12-01

The acceleration of atomic nucleus beam with the 12 GeV proton synchrotron in National Laboratory for High Energy Physics (KEK-PS) has been demanded by the experimenters of nuclear physics, and there was the move to concretely realize it at the beginning of 1980, but actually it was not materialized up to now due to various circumstances. The reason that makes the acceleration even in light nuclear beam like deuterons difficult is various, but one is that the acceleration method considered so far particularly in a booster main ring is very complicated. Recently as one of the various proposals made from the viewpoint of the future utilization of the KEK-PS, that of using nuclear beam and the experiment with the PS-collider have been discussed, and the method of accelerating nuclear beam in the PS was reexamined. As the result, together with the technical progress such as ring RF and linear accelerator augmentation, the method with high realization possibility became to be proposed. This proceedings is the report of the first workshop on deutron acceleration held on February 20, 1991, to prepare for the experiment using deuteron beam. (K.I.)

Report of the accelerator and beam line options working group

International Nuclear Information System (INIS)

Ankenbrandt, C.; Bogacz, A.; Bogert, D.; Bossert, R.C.; Brown, B.; Childress, S.; Crawford, C.; Dugan, G.; Even, L.; Finley, D.; Gelfand, N.; Gerig, R.; Goderre, G.; Gourlay, S.; Griffin, J.; Hahn, A.; Holmes, S.; Jackson, G.; Johnson, R.; Johnson, D.; Kerby, J.; Koepke, K.; Koizumi, G.; Koul, R.; Lamm, M.; MacLachlan, J.; Malamud, E.; Malensek, A.; Mantsch, P.; Marriner, J.; Marsh, B.; Martin, P.; Hills, F.; Moore, C.; Murphy, T.; Nicol, T.; Peterson, T.; Pruss, S.; Rameika, G.; Riddiford, A.; Rosenzweig, J.; Russell, A.; Saritepe, S.; Stahl, S.; Strait, J.; Trbojevic, D.; Visnjic, V.; Volk, J.; Johnson, D.; Syphers, M.; Mohl, D.; Ruggiero, S.; Collins, T.

1990-01-01

This report summarizes work done before, during, and after the conference. The group was broken down into six subgroups. Subgroup 1 considered collider aspects of the phase 1 and phase 2 upgrade plans. Also considered were the collider aspects of a specific example of Phase 3, namely the replacement of the Tevatron with a new ring providing 1.8 TeV per beam. Subgroup 2 considered specific improvements to the proposed Main Injector (MI) which will enhance the performance of Phase 2. Also considered were improvements which may be made to the present Main Ring (MR) which will enchance performance of Phase 1. Subgroup 3 considered fixed target aspects of the Phase 1 and 2 upgrade plans and a specific example of Phase 3, namely the replacement of the Tevatron with a new ring providing 1.5 TeV fixed target operation. Subgroup 4 considered the external beam lines associated with the upgrades. Subgroup 5 considered the new designs of the superconducting magnets and associated large cryogenic systems connected with the accelerator systems proposed by the other groups. Subgroup 6 assumed the existence of Phase 1 and 2 upgrades and considered new possibilities for Phase 3 such as new accelerators in new tunnels

Gas delivery system and beamline studies for the test beam facility of the Collider Detector at Fermilab

International Nuclear Information System (INIS)

Franke, H.G. III.

1987-12-01

A fixed-target test beam facility has been designed and constructed at the Meson Test (MT) site to support studies of components of the Collider Detector at Fermi National Accelerator Laboratory (CDF). I assisted in the design and constuction of the test beam facility gas delivery system, and I conducted the initial studies to document the ability of the MT beamline to meet the needs of CDF. Analysis of the preliminary performance data on MT beamline components and beam tunes at required particle energies is presented. Preliminary studies show that the MT beamline has the necessary flexibility to satisfy most CDF requirements now

Linear collider research and development at SLAC, LBL and LLNL

International Nuclear Information System (INIS)

Mattison, T.S.

1988-10-01

The study of electron-positron (e + e/sup /minus//) annihilation in storage ring colliders has been very fruitful. It is by now well understood that the optimized cost and size of e + e/sup /minus// storage rings scales as E(sub cm//sup 2/ due to the need to replace energy lost to synchrotron radiation in the ring bending magnets. Linear colliders, using the beams from linear accelerators, evade this scaling law. The study of e/sup +/e/sup /minus// collisions at TeV energy will require linear colliders. The luminosity requirements for a TeV linear collider are set by the physics. Advanced accelerator research and development at SLAC is focused toward a TeV Linear Collider (TLC) of 0.5--1 TeV in the center of mass, with a luminosity of 10/sup 33/--10/sup 34/. The goal is a design for two linacs of less than 3 km each, and requiring less than 100 MW of power each. With a 1 km final focus, the TLC could be fit on Stanford University land (although not entirely within the present SLAC site). The emphasis is on technologies feasible for a proposal to be framed in 1992. Linear collider development work is progressing on three fronts: delivering electrical energy to a beam, delivering a focused high quality beam, and system optimization. Sources of high peak microwave radio frequency (RF) power to drive the high gradient linacs are being developed in collaboration with Lawrence Berkeley Laboratory (LBL) and Lawrence Livermore National Laboratory (LLNL). Beam generation, beam dynamics and final focus work has been done at SLAC and in collaboration with KEK. Both the accelerator physics and the utilization of TeV linear colliders were topics at the 1988 Snowmass Summer Study. 14 refs., 4 figs., 1 tab

Ultimate-gradient accelerators physics and prospects

CERN Document Server

Skrinsky, Aleksander Nikolayevich

1995-01-01

As introduction, the needs and ways for ultimate acceleration gradients are discussed briefly. The Plasma Wake Field Acceleration is analized in the most important details. The structure of specific plasma oscillations and "high energy driver beam SP-plasma" interaction is presented, including computer simulation of the process. Some pratical ways to introduce the necessary mm-scale bunching in driver beam and to arrange sequential energy multiplication are dicussed. The influence of accelerating beam particle - plasma binary collisions is considered, also. As applications of PWFA, the use of proton super-colliders beams (LHC and Future SC) to drive the "multi particle types" accelerator, and the arrangements for the electron-positron TeV range collider are discussed.

Sixth international workshop on linear colliders. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Urakawa, Junji [ed.

1995-08-01

The sixth international workshop on linear colliders (LC95) was held by KEK at Tsukuba Center for Institute. In the workshop 8 parallel working group were organized: WG1 (beam sources and injection linacs), WG2 (damping rings and bunch compressors), WG3 (a: RF sources and structures, b: superconducting cavities, c: two beam accelerators), WG4 (beam dynamics in main linacs), WG5 (final focus and integration regions), WG6 (beam instrumentation), WG7 (overall parameters and construction techniques), WG8 (gamma-gamma collider and miscellaneous). This issue compiles materials which were used in the workshop. (J.P.N.).

Sixth international workshop on linear colliders. Proceedings

International Nuclear Information System (INIS)

Urakawa, Junji

1995-08-01

The sixth international workshop on linear colliders (LC95) was held by KEK at Tsukuba Center for Institute. In the workshop 8 parallel working group were organized: WG1 (beam sources and injection linacs), WG2 (damping rings and bunch compressors), WG3 (a: RF sources and structures, b: superconducting cavities, c: two beam accelerators), WG4 (beam dynamics in main linacs), WG5 (final focus and integration regions), WG6 (beam instrumentation), WG7 (overall parameters and construction techniques), WG8 (gamma-gamma collider and miscellaneous). This issue compiles materials which were used in the workshop. (J.P.N.)

Steady state distribution for unbunched beams colliding in a drift space

International Nuclear Information System (INIS)

Kheifets, S.; Chao, A.W.

1979-12-01

A self-consistent time-independent solution of the system of coupled equations for the distribution of two colliding unbunched beams of opposite charges is found. The solution for each beam contains an arbitrary constant which characterizes the lateral size of the beam. On the other hand, the angular divergence is uniquely determined by the line charge density of the opposite beam in case the beams have cylindrical symmetry. The possible implications of this solution for a linac collider are discussed. Further work on the stability of this solution is needed. 6 refs., 9 figs., 2 tabs

Nonlinear interaction of colliding beams in particle storage rings

International Nuclear Information System (INIS)

Herrera, J.C.; Month, M.

1979-01-01

When two beams of high energy particles moving in opposite directions are brought into collision, a large amount of energy is available for the production of new particles. However to obtain a sufficiently high event rate for rare processes, such as the production of the intermediate vector boson (Z 0 and W +- ), large beam currents are also required. Under this circumstance, the high charge density of one beam results in a classical electromagnetic interaction on the particles in the other beam. This very nonlinear space charge force, caled the beam-beam force, limits the total circulating charge and, thereby, the ultimate performance of the colliding ring system. The basic nature of the beam-beam force is discussed, indicating how it is quite different in the case of continuous beams, which cross each other at an angle as compared to the case of bunched beams which collide head-on. Some experimental observations on the beam-beam interaction in proton-proton and electron-positron beams are then reviewed and interpreted. An important aspect of the beam-beam problem in storage rings is to determine at what point in the analysis of the particle dynamics is it relevant to bring in the concepts of stochasticity, slow diffusion, and resonance overlap. These ideas are briefly discussed

Polarized electron sources for linear colliders

International Nuclear Information System (INIS)

Clendenin, J.E.; Ecklund, S.D.; Miller, R.H.; Schultz, D.C.; Sheppard, J.C.

1992-07-01

Linear colliders require high peak current beams with low duty factors. Several methods to produce polarized e - beams for accelerators have been developed. The SLC, the first linear collider, utilizes a photocathode gun with a GaAs cathode. Although photocathode sources are probably the only practical alternative for the next generation of linear colliders, several problems remain to be solved, including high voltage breakdown which poisons the cathode, charge limitations that are associated with the condition of the semiconductor cathode, and a relatively low polarization of ≤5O%. Methods to solve or at least greatly reduce the impact of each of these problems are at hand

Test of the beam effect on vacuum arc occurrence in a high-gradient accelerating structure for the CLIC project

CERN Document Server

AUTHOR|(CDS)2130409; Gagliardi, Martino

A new generation of lepton colliders capable of reaching TeV energies is pres- ently under development, and to succeed in this task it is necessary to show that the technology for such a machine is available. The Compact Linear Collider (CLIC) is a possible design option among the future lepton collider projects. It consists of two normal-conducting linacs. Accelerating structures with a gradient of the order of 100 MV/m are necessary to reach the required high energies within a reasonable machine length. One of the strictest require- ments for such accelerating structures is a relatively low occurrence of vacuum arcs. CLIC prototype structures have been tested in the past, but only in absence of beam. In order to proof the feasibility of the high gradient technology for building a functional collider, it is necessary to understand the effect of the beam presence on the vacuum breakdowns. Tests of this type have never been performed previously. The main goal of this work is to provide a first measurement of t...

CLIC: developing a linear collider

CERN Multimedia

Laurent Guiraud

1999-01-01

Compact Linear Collider (CLIC) is a CERN project to provide high-energy electron-positron collisions. Instead of conventional radio-frequency klystrons, CLIC will use a low-energy, high-intensity primary beam to produce acceleration.

Progress towards the design of a next linear collider

International Nuclear Information System (INIS)

Ruth, R.D.

1990-06-01

The purpose of this paper is to review the ongoing research at SLAC toward the design of a next-generation linear collider (NLC). The energy of the collider is taken to be 0.5 TeV in the CM with a view towards upgrading to 1.0 TeV. The luminosity is in the range of 10 33 to 10 34 cm -2 sec -1 . The energy is achieved by acceleration with a gradient of about a factor of five higher than SLC, which yields a linear collider approximately twice as long as SLC. The detailed trade-off length and acceleration will be based on total cost. A very broad optimum occurs when the total linear costs equals the total cost of RF power. The luminosity of the linear collider is obtained basically in two ways. First, the cross-sectional area of the beam is decreased primarily by decreasing the vertical size. This creates a flat beam and is useful for controlling beamstrahlung. Secondly, several bunches (∼10) are accelerated on each RF fill in order to more efficiently extract energy from the RF structure. This effectively increases the repetition rate by an order of magnitude. In the next several sections, we trace the beam through the collider to review the research program at SLAC. 41 refs., 1 fig

Activation of the IFMIF prototype accelerator and beam dump by deuterons and protons

Czech Academy of Sciences Publication Activity Database

Simakov, S. P.; Bém, Pavel; Burjan, Václav; Fischer, U.; Forrest, R.A.; Götz, Miloslav; Honusek, Milan; Klein, H.; Kroha, Václav; Novák, Jan; Sauer, A.; Šimečková, Eva; Tiede, R.

2008-01-01

Roč. 83, 10-12 (2008), s. 1543-1547 ISSN 0920-3796 R&D Projects: GA MPO 2A-1TP1/101 Institutional research plan: CEZ:AV0Z10480505 Keywords : IFMIF * Protons and deuterons accelerator * Beam dump Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.828, year: 2008

Brookhaven highlights, October 1978-September 1979. [October 1978 to September 1979

Energy Technology Data Exchange (ETDEWEB)

1979-01-01

These highlights present an overview of the major research and development achievements at Brookhaven National Laboratory from October 1978 to September 1979. Specific areas covered include: accelerator and high energy physics programs; high energy physics research; the AGS and improvements to the AGS; neutral beam development; heavy ion fusion; superconducting power cables; ISABELLE storage rings; the BNL Tandem accelerator; heavy ion experiments at the Tandem; the High Flux Beam Reactor; medium energy physics; nuclear theory; atomic and applied physics; solid state physics; neutron scattering studies; x-ray scattering studies; solid state theory; defects and disorder in solids; surface physics; the National Synchrotron Light Source ; Chemistry Department; Biology Department; Medical Department; energy sciences; environmental sciences; energy technology programs; National Center for Analysis of Energy Systems; advanced reactor systems; nuclear safety; National Nuclear Data Center; nuclear materials safeguards; Applied Mathematics Department; and support activities. (GHT)

Accelerators course

CERN Multimedia

CERN. Geneva HR-RFA; Métral, E

2006-01-01

1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges

Future Accelerator Challenges in Support of High-Energy Physics

International Nuclear Information System (INIS)

Zisman, Michael S.; Zisman, M.S.

2008-01-01

Historically, progress in high-energy physics has largely been determined by development of more capable particle accelerators. This trend continues today with the imminent commissioning of the Large Hadron Collider at CERN, and the worldwide development effort toward the International Linear Collider. Looking ahead, there are two scientific areas ripe for further exploration--the energy frontier and the precision frontier. To explore the energy frontier, two approaches toward multi-TeV beams are being studied, an electron-positron linear collider based on a novel two-beam powering system (CLIC), and a Muon Collider. Work on the precision frontier involves accelerators with very high intensity, including a Super-BFactory and a muon-based Neutrino Factory. Without question, one of the most promising approaches is the development of muon-beam accelerators. Such machines have very high scientific potential, and would substantially advance the state-of-the-art in accelerator design. The challenges of the new generation of accelerators, and how these can be accommodated in the accelerator design, are described. To reap their scientific benefits, all of these frontier accelerators will require sophisticated instrumentation to characterize the beam and control it with unprecedented precision

Future Accelerator Challenges in Support of High-Energy Physics

Energy Technology Data Exchange (ETDEWEB)

Zisman, Michael S.; Zisman, M.S.

2008-05-03

Historically, progress in high-energy physics has largely been determined by development of more capable particle accelerators. This trend continues today with the imminent commissioning of the Large Hadron Collider at CERN, and the worldwide development effort toward the International Linear Collider. Looking ahead, there are two scientific areas ripe for further exploration--the energy frontier and the precision frontier. To explore the energy frontier, two approaches toward multi-TeV beams are being studied, an electron-positron linear collider based on a novel two-beam powering system (CLIC), and a Muon Collider. Work on the precision frontier involves accelerators with very high intensity, including a Super-BFactory and a muon-based Neutrino Factory. Without question, one of the most promising approaches is the development of muon-beam accelerators. Such machines have very high scientific potential, and would substantially advance the state-of-the-art in accelerator design. The challenges of the new generation of accelerators, and how these can be accommodated in the accelerator design, are described. To reap their scientific benefits, all of these frontier accelerators will require sophisticated instrumentation to characterize the beam and control it with unprecedented precision.

Design of a relativistic klystron two-beam accelerator prototype

International Nuclear Information System (INIS)

Westenskow, G.; Caporaso, G.; Chen, Y.

1995-01-01

We are designing an experiment to study physics, engineering, and costing issues of an extended Relativistic Klystron Two-Beam Accelerator (RK-TBA). The experiment is a prototype for an RK-TBA based microwave power source suitable for driving a 1 TeV linear collider. Major components of the experiment include a 2.5-MV, 1.5-kA electron source, a 11.4-GHz modulator, a bunch compressor, and a 8-m extraction section. The extraction section will be comprised of 4 traveling-wave output structures, each generating about 360 MW of rf power. Induction cells will be used in the extraction section to maintain the average beam energy at 5 MeV. Status of the design is presented

Beam based alignment at the KEK accelerator test facility

International Nuclear Information System (INIS)

Ross, M.; Nelson, J.; Woodley, M.; Wolski, A.

2002-01-01

The KEK Accelerator Test Facility (ATF) damping ring is a prototype low emittance source for the NLC/JLC linear collider. To achieve the goal normalized vertical emittance gey = 20 nm-rad, magnet placement accuracy better than 30 mm must be achieved. Accurate beam-based alignment (BBA) is required. The ATF arc optics uses a FOBO cell with two horizontally focusing quadrupoles, two sextupoles and a horizontally defocusing gradient dipole, all of which must be aligned with BBA. BBA at ATF uses the quadrupole and sextupole trim windings to find the trajectory through the center of each magnet. The results can be interpreted to assess the accuracy of the mechanical alignment and the beam position monitor offsets

Accelerators of future generation

International Nuclear Information System (INIS)

Kolomenskij, A.A.

1983-01-01

A brief review of the prospects of development of various of types accelerator over next 10 to 15 years is given. The following directions are considered: superhign energy proton accelerators and storage rings, electron-positron colliding beams, heavy ion accelerators, medium energy, high-current proton accelerators superhigh power particle beams (electrons light- and heavy ions) for inertial fusion

Beam Dynamics Challenges for Future Circular Colliders

CERN Multimedia

Zimmermann, Frank

2004-01-01

The luminosity of hadron colliders rises with the beam intensity, until some limit is encountered, mostly due to head-on and long-range beam-beam interaction, due to electron cloud, or due to conventional impedance sources. Also beam losses caused by various mechanisms may affect the performance. The limitations can be alleviated, if not overcome, by a proper choice of beam parameters and by dedicated compensation schemes. Examples include alternating crossing at several interaction points, electromagnetic wires, super-bunches, electron lenses, clearing electrodes, and nonlinear collimation. I discuss such mitigating measures and related research efforts, with special emphasis on the LHC and its upgrade.

Landmarks in particle physics at Brookhaven National Laboratory: Brookhaven Lecture Series, Number 238

International Nuclear Information System (INIS)

Adair, R.K.

1987-01-01

Robert Adair's lecture on Landmarks in Particle Physics at Brookhaven National Laboratory (BNL) is a commemoration of the 40th Anniversary of Brookhaven National Laboratory. Adair describes ten researches in elementary particle physics at Brookhaven that had a revolutionary impact on the understanding of elementary particles. Two of the discoveries were made in 1952 and 1956 at the Cosmotron, BNL's first proton accelerator. Four were made in 1962 and 1964 at the Alternating Gradient Synchrotron, the Cosmotron's replacement. Two other discoveries in 1954 and 1956 were theoretical, and strong focusing (1952) is the only technical discovery. One discovery (1958) happened in an old barrack. Four of the discoveries were awarded the Nobel prize in Physics. Adair believes that all of the discoveries are worthy of the Nobel prize. 14 figs

Design study of longitudinal dynamics of the drive beam in 1 TeV relativistic klystron two-beam accelerator

International Nuclear Information System (INIS)

Li, H.; Yu, S.S.; Sessler, A.M.

1994-10-01

In this paper the authors present a design study on the longitudinal dynamics of a relativistic klystron two-beam accelerator (RK-TBA) scheme which has been proposed as a power source candidate for a 1 TeV next linear collider (NLC). They address the issue of maintaining stable power output at desired level for a 300-m long TBA with 150 extraction cavities and present their simulation results to demonstrate that it can be achieved by inductively detuning the extraction cavities to counter the space charge debunching effect on the drive beam. They then carry out simulation study to show that the beam bunches desired by the RK-TBA can be efficiently obtained by first chopping an initially uniform beam of low energy into a train of beam bunches with modest longitudinal dimension and then using the open-quotes adiabatic captureclose quotes scheme to bunch and accelerate these beam bunches into tight bunches at the operating energy of the drive beam. The authors have also examined the open-quotes after burnerclose quotes scheme which is implemented in their RK-TBA design for efficiency enhancement

Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider

CERN Document Server

Sun, Y P; Barranco, J; Tomás, R; Weiler, T; Zimmermann, F; Calaga, R; Morita, A

2009-01-01

Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The long-range beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing a crossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit...

Scaling laws for e+/e- linear colliders

International Nuclear Information System (INIS)

Delahaye, J.P.; Guignard, G.; Raubenheimer, T.; Wilson, I.

1999-01-01

Design studies of a future TeV e + e - Linear Collider (TLC) are presently being made by five major laboratories within the framework of a world-wide collaboration. A figure of merit is defined which enables an objective comparison of these different designs. This figure of merit is shown to depend only on a small number of parameters. General scaling laws for the main beam parameters and linac parameters are derived and prove to be very effective when used as guidelines to optimize the linear collider design. By adopting appropriate parameters for beam stability, the figure of merit becomes nearly independent of accelerating gradient and RF frequency of the accelerating structures. In spite of the strong dependence of the wake fields with frequency, the single-bunch emittance blow-up during acceleration along the linac is also shown to be independent of the RF frequency when using equivalent trajectory correction schemes. In this situation, beam acceleration using high-frequency structures becomes very advantageous because it enables high accelerating fields to be obtained, which reduces the overall length and consequently the total cost of the linac. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Quadrupole modes in linearized beam-beam interaction in e+e- colliding rings

International Nuclear Information System (INIS)

Matsumoto, Shuji; Hirata, Kohji.

1992-01-01

The dynamic-beta model is extended, incorporating the synchrotron radiation effects. The model yields dynamic-emittance effect. The steady-state envelope matrix is explicitly obtained. Both equal-beam and flip-flop solutions are found. The stability of the steady-state solutions are investigated by numerical calculations. The model illustrates some characteristic features of the beam-beam interaction at e + e - colliding rings in spite of containing some qualitatively unrealistic points. (author)

Performance Limitations in High-Energy Ion Colliders

CERN Document Server

Fischer, Wolfram

2005-01-01

High-energy ion colliders (hadron colliders operating with species other than protons) are premier research tools for nuclear physics. The collision energy and high luminosity are important design and operations considerations. However, the experiments also expect flexibility with frequent changes in the collision energy, lattice configuration, and ion species, including asymmetric collisions. For the creation, acceleration, and storage of bright intense ion beams, attention must be paid to space charge, charge exchange, and intra-beam scattering effects. The latter leads to luminosity lifetimes of only a few hours for heavy ions. Ultimately cooling at full energy is needed to overcome this effect. Currently, the Relativistic Heavy Ion Collider at BNL is the only operating high-energy ion collider. The Large Hadron Collider, under construction at CERN, will also run with heavy ions.

The International Linear Collider Technical Design Report - Volume 3.I: Accelerator \\& in the Technical Design Phase

Energy Technology Data Exchange (ETDEWEB)

Adolphsen, Chris [SLAC National Accelerator Lab., Menlo Park, CA (United States); et al.

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.

Beam Dynamics Studies for a Laser Acceleration Experiment

CERN Document Server

Spencer, James; Noble, Robert; Palmer, Dennis T; Siemann, Robert

2005-01-01

The NLC Test Accelerator at SLAC was built to address various beam dynamics issues for the Next Linear Collider. An S-Band RF gun, originally proposed for the NLCTA, is being installed together with a large-angle extraction line at 60 MeV. This is followed by a matching section, final focus and buncher for the laser acceleration experiment, E163. The laser-electron interaction area is followed by a broad range, high resolution spectrometer (HES) for electron bunch analysis. The RF gun is discussed in another paper. We discuss only the beam dynamics and high resolution analysis system at 6 MeV based on using Parmela and high-order Transport for bunch charges from 50 pC to 1 nC. Beyond the diagnostics, this system uses the emittance compensating solenoids and a low energy, high resolution spectrometer (LES) to help tune for best operating point and match to the linac. Optical symmetries in the design of the 25.5° extraction line provide 1:1 phase space transfer without linear dispersion or use of sextu...

Cavity beam position monitor system for the Accelerator Test Facility 2

Science.gov (United States)

Kim, Y. I.; Ainsworth, R.; Aryshev, A.; Boogert, S. T.; Boorman, G.; Frisch, J.; Heo, A.; Honda, Y.; Hwang, W. H.; Huang, J. Y.; Kim, E.-S.; Kim, S. H.; Lyapin, A.; Naito, T.; May, J.; McCormick, D.; Mellor, R. E.; Molloy, S.; Nelson, J.; Park, S. J.; Park, Y. J.; Ross, M.; Shin, S.; Swinson, C.; Smith, T.; Terunuma, N.; Tauchi, T.; Urakawa, J.; White, G. R.

2012-04-01

The Accelerator Test Facility 2 (ATF2) is a scaled demonstrator system for final focus beam lines of linear high energy colliders. This paper describes the high resolution cavity beam position monitor (BPM) system, which is a part of the ATF2 diagnostics. Two types of cavity BPMs are used, C-band operating at 6.423 GHz, and S-band at 2.888 GHz with an increased beam aperture. The cavities, electronics, and digital processing are described. The resolution of the C-band system with attenuators was determined to be approximately 250 nm and 1μm for the S-band system. Without attenuation the best recorded C-band cavity resolution was 27 nm.

High energy accelerator and colliding beam user group

International Nuclear Information System (INIS)

1990-09-01

This report discusses the following topics: OPAL experiment at LEP; Dφ experiment at Fermilab; deep inelastic muon interactions at TEV II; CYGNUS experiment; final results from ν e -e elastic scattering; physics with CLEO detector at CESR; results from JADE at PETRA; rare kaon-decay experiment at BNL; search for top quark; and super conducting super collider activities

The first colliders: AdA, VEP-1 and Princeton-Stanford

Energy Technology Data Exchange (ETDEWEB)

Shiltsev, V. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

2013-07-11

The idea of exploring collisions in the center-of-mass system to fully exploit the energy of the accelerated particles had been given serious consideration by the Norwegian engineer and inventor Rolf Wideröe, who had applied for a patent on the idea in 1943 (and got the patent in 1953 [1]) after considering the kinematic advantage of keeping the center of mass at rest to produce larger momentum transfers. Describing this advantage G.K.O’Neill, one of the collider pioneers, wrote in 1956 [2]: “…as accelerators of higher and higher energy are built, their usefulness is limited by the fact that the energy available for creating new particles is measured in the center-of-mass system of the target nucleon and the bombarding particle. In the relativistic limit, this energy rises only as the square root of the accelerator energy. However, if two particles of equal energy traveling in opposite directions could be made to collide, the available energy would be twice the whole energy of one particle...” Therefore, no kinetic energy is wasted by the motion of the center of mass of the system, and the available reaction energy E_R = 2E_beam (while a particle with the same energy E_beam colliding with another particle of the mass m at rest produces only E_R = (2E_beam m)½ in the extreme relativistic case.) One can also add that the colliders are “cleaner” machines with respect to the fixed target ones since the colliding beams do not interact with the target materials. The other advantage is that it is much easier to organize collisions of beams composed of matter-antimatter particles, like in electron-positron and proton-antiproton colliders.

Experimental support at proton--proton colliding beam facilities

International Nuclear Information System (INIS)

Potter, K.

1977-01-01

Proton--proton colliding beam facilities have a number of special features which increase the importance of support for experiments when compared to fixed target accelerators: (1) the laboratory system is very close to the center-of-mass system; this affects the geometry and general size of the experiments; (2) the primary p--p interaction is inaccessible, that is, it takes place in an ultrahigh vacuum chamber; and (3) the experiment detection system is necessarily inside the machine structure and becomes very closely linked to it in many respects. An overall picture is given of experimental support based on experience at the CERN ISR under the following headings: Experimental Areas, Scheduling, Intersection Vacuum Chambers, Machine Background, and Magnets for Experiments. The first two of these topics concern the requirements in space and time of an experiment, while the last three are all related to the close interaction between experiment and machine

Equilibrium state of colliding electron beams

Directory of Open Access Journals (Sweden)

R. L. Warnock

2003-10-01

Full Text Available We study a nonlinear integral equation that is a necessary condition on the equilibrium phase-space distribution function of stored, colliding electron beams. It is analogous to the Haïssinski equation, being derived from Vlasov-Fokker-Planck theory, but is quite different in form. The equation is analyzed for the case of the Chao-Ruth model of the beam-beam interaction in 1 degree of freedom, a so-called strong-strong model with nonlinear beam-beam force. We prove the existence of a unique solution, for sufficiently small beam current, by an application of the implicit function theorem. We have not yet proved that this solution is positive, as would be required to establish existence of an equilibrium. There is, however, numerical evidence of a positive solution. We expect that our analysis can be extended to more realistic models.

The CERN linear collider test facility (CTF)

International Nuclear Information System (INIS)

Baconnier, Y.; Battisti, S.; Bossart, R.; Delahaye, J.P.; Geissler, K.K.; Godot, J.C.; Huebner, K.; Madsen, J.H.B.; Potier, J.P.; Riche, A.J.; Sladen, J.; Suberlucq, G.; Wilson, I.; Wuensch, W.

1992-01-01

The CTF (Collider Test Facility) was brought into service last year. The 3 GHz gun produced a beam of 3 MeV/c which was accelerated to 40 MeV/c. This beam, passing a prototype CLIC (linear collider) structure, generated a sizeable amount of 30 GHz power. This paper describes the results and experience with the gun driven by a 8 ns long laser pulse and its CsI photo cathode, the beam behaviour, the beam diagnostics in particular with the bunch measurements by Cerenkov or transition radiation light and streak camera, the photo cathode research, and the beam dynamics studies on space charge effects. (Author)4 figs., tab., 6 refs

A Future Linear Collider with Polarised Beams: Searches for New Physics

International Nuclear Information System (INIS)

Moortgat-Pick, Gudrid

2003-01-01

There exists a world-wide consensus for a future e+e- Linear Collider in the energy range between √(s) =500-1000 GeV as the next large facility in HEP. The Linear Collider has a large physics potential for the discovery of new physics beyond the Standard Model and for precision studies of the Standard Model itself. It is well suited to complement and extend the physics program of the LHC. The use of polarised beams at a Linear Collider will be a powerful tool. In this paper we will summarize some highlights of high precision tests of the electroweak theory and of searches for physics beyond the Standard Model at a future Linear Collider with polarised e- and e+ beams

Beam life-time with intrabeam scattering and stochastic cooling

International Nuclear Information System (INIS)

Wei, J.; Ruggiero, A.G.

1991-01-01

A transport equation has been derived in terms of the longitudinal action variable to describe the time evolution of the longitudinal density distribution of a bunched hadron beam in the presence of intrabeam scattering and stochastic cooling. A computer program has been developed to numerically solve this equation. Both beam loss and bunch-shape evolution have been investigated for the 197 Au 79+ beams during the 10-hour storage in the Relativistic Heavy Ion Collider currently under construction at the Brookhaven National Laboratory. 9 refs., 1 fig

An R and D program for targetry and capture at a neutrino factory and muon collider source

International Nuclear Information System (INIS)

Hassenein, A.; Bernadon, A.; Beshears, D.L.; Brown, K.A.; Cates, M.C.; Fabich, A.; Fernow, R.C.; Finfrock, C.C.; Fukui, Y.; Gabriel, T.A.; Gassner, D.M.; Green, M.A.; Greene, G.A.; Haines, J.R.; Johnson, C.D.; Kahn, S.A.; King, B.J.; Kirk, H.G.; Lettry, J.; Lu, C.; Ludewig, H.; McDonald, K.T.; Miller, J.R.; Mokhov, N.V.; Palmer, R.B.; Pendzick, A.F.; Prigl, R.; Ravn, H.; Reginato, L.L.; Riemer, B.W.; Samulyak, R.; Scaduto, J.; Simos, N.; Spampinato, P.T.; Thieberger, P.; Tsai, C.-C.; Tsang, T.Y.F.; Wang, H.; Weggel, R.J.; Zeller, A.

2003-01-01

The need for intense muon beams for muon colliders and for neutrino factories based on muon storage rings leads to a concept of 1-4 MW proton beams incident on a moving target that is inside a 20-T solenoid magnet, with a mercury jet as a preferred example. Novel technical issues for such a system include disruption of the mercury jet by the proton beam and distortion of the jet on entering the solenoid, as well as more conventional issues of materials lifetime and handling of activated materials in an intense radiation environment. As part of the R and D program of the Neutrino Factory and Muon Collider Collaboration, an R and D effort related to targetry is being performed within the context of experiment E951 at Brookhaven National Laboratory, first results of which are reported here

Linear accelerators for TeV colliders. Revision

International Nuclear Information System (INIS)

Wilson, P.B.

1985-10-01

The basic scaling relations for important linear collider design parameters are introduced. Some of the basic concepts concerning the design of accelerating structures are presented, and breakdown limitations are discussed. Rf power sources are considered. Some of the key concepts of wakefield accelerators are discussed, and some examples of wake fields for typical linac structures are presented. Some general concepts concerning emittance, and the limitations on the emittance that can be obtained from linac guns and damping rings are discussed. 49 refs., 15 figs

Linear collider applications of superconducting RF

International Nuclear Information System (INIS)

Rubin, D.L.

1990-01-01

The most promising technology for producing interactions of electrons and positrons in TeV energy range is the linear collider. In the linear collider each and every collision of charged particles depends on the production of the charges at rest and then the acceleration of those charges to full energy. The particles that exit the interaction region are discharded. A consequence of this mode of operation is that the luminosity of the machine is ultimately determined by the efficiency with which AC power can be converted into beam power. The consideration of superconducting cavities is motivated by the need for high efficiency. Thus, the high emittance around a beam collider and low emittance around beams are discussed first in the present report. Flat beams are then addressed focusing on the characteristics of the source, final focus, and beam stability. The beam stability, in particular, is discussed in detail in relation to the multiple bunch transverse stability, wake field induced energy spread, trapped modes, pulse width, duty cycle, RF power, and refrigerator power. (N.K.)

High energy accelerator and colliding beam user group

Energy Technology Data Exchange (ETDEWEB)

1990-09-01

This report discusses the following topics: OPAL experiment at LEP; D{phi} experiment at Fermilab; deep inelastic muon interactions at TEV II; CYGNUS experiment; final results from {nu}{sub e}{sup {minus}e} elastic scattering; physics with CLEO detector at CESR; results from JADE at PETRA; rare kaon-decay experiment at BNL; search for top quark; and super conducting super collider activities.

Numerical Integration of the Vlasov Equation of Two Colliding Beams

CERN Document Server

Zorzano-Mier, M P

2000-01-01

In a circular collider the motion of particles of one beam is strongly perturbed at the interaction points by the electro-magnetic field associated with the counter-rotating beam. For any two arbitrary initial particle distributions the time evolution of the two beams can be known by solving the coupled system of two Vlasov equations. This collective description is mandatory when the two beams have similar strengths, as in the case of LEP or LHC. The coherent modes excited by this beam-beam interaction can be a strong limitation for the operation of LHC. In this work, the coupled Vlasov equations of two colliding flat beams are solved numerically using a finite difference scheme. The results suggest that, for the collision of beams with equal tunes, the tune shift between the $\\sigma$- and $\\pi$- coherent dipole mode depends on the unperturbed tune $q$ because of the deformation that the so-called dynamic beta effect induces on the beam distribution. Only when the unperturbed tune $q\\rightarrow 0.25$ this tun...

The International Linear Collider Technical Design Report - Volume 3.I: Accelerator R&D in the Technical Design Phase

CERN Document Server

Adolphsen, Chris; Barish, Barry; Buesser, Karsten; Burrows, Philip; Carwardine, John; Clark, Jeffrey; Durand, Hélène Mainaud; Dugan, Gerry; Elsen, Eckhard; Enomoto, Atsushi; Foster, Brian; Fukuda, Shigeki; Gai, Wei; Gastal, Martin; Geng, Rongli; Ginsburg, Camille; Guiducci, Susanna; Harrison, Mike; Hayano, Hitoshi; Kershaw, Keith; Kubo, Kiyoshi; Kuchler, Victor; List, Benno; Liu, Wanming; Michizono, Shinichiro; Nantista, Christopher; Osborne, John; Palmer, Mark; Paterson, James McEwan; Peterson, Thomas; Phinney, Nan; Pierini, Paolo; Ross, Marc; Rubin, David; Seryi, Andrei; Sheppard, John; Solyak, Nikolay; Stapnes, Steinar; Tauchi, Toshiaki; Toge, Nobu; Walker, Nicholas; Yamamoto, Akira; Yokoya, Kaoru

2013-01-01

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carried out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to incr...

Simulations and measurements of beam loss patterns at the CERN Large Hadron Collider

Science.gov (United States)

Bruce, R.; Assmann, R. W.; Boccone, V.; Bracco, C.; Brugger, M.; Cauchi, M.; Cerutti, F.; Deboy, D.; Ferrari, A.; Lari, L.; Marsili, A.; Mereghetti, A.; Mirarchi, D.; Quaranta, E.; Redaelli, S.; Robert-Demolaize, G.; Rossi, A.; Salvachua, B.; Skordis, E.; Tambasco, C.; Valentino, G.; Weiler, T.; Vlachoudis, V.; Wollmann, D.

2014-08-01

The CERN Large Hadron Collider (LHC) is designed to collide proton beams of unprecedented energy, in order to extend the frontiers of high-energy particle physics. During the first very successful running period in 2010-2013, the LHC was routinely storing protons at 3.5-4 TeV with a total beam energy of up to 146 MJ, and even higher stored energies are foreseen in the future. This puts extraordinary demands on the control of beam losses. An uncontrolled loss of even a tiny fraction of the beam could cause a superconducting magnet to undergo a transition into a normal-conducting state, or in the worst case cause material damage. Hence a multistage collimation system has been installed in order to safely intercept high-amplitude beam protons before they are lost elsewhere. To guarantee adequate protection from the collimators, a detailed theoretical understanding is needed. This article presents results of numerical simulations of the distribution of beam losses around the LHC that have leaked out of the collimation system. The studies include tracking of protons through the fields of more than 5000 magnets in the 27 km LHC ring over hundreds of revolutions, and Monte Carlo simulations of particle-matter interactions both in collimators and machine elements being hit by escaping particles. The simulation results agree typically within a factor 2 with measurements of beam loss distributions from the previous LHC run. Considering the complex simulation, which must account for a very large number of unknown imperfections, and in view of the total losses around the ring spanning over 7 orders of magnitude, we consider this an excellent agreement. Our results give confidence in the simulation tools, which are used also for the design of future accelerators.

Simulations and measurements of beam loss patterns at the CERN Large Hadron Collider

Directory of Open Access Journals (Sweden)

R. Bruce

2014-08-01

Full Text Available The CERN Large Hadron Collider (LHC is designed to collide proton beams of unprecedented energy, in order to extend the frontiers of high-energy particle physics. During the first very successful running period in 2010–2013, the LHC was routinely storing protons at 3.5–4 TeV with a total beam energy of up to 146 MJ, and even higher stored energies are foreseen in the future. This puts extraordinary demands on the control of beam losses. An uncontrolled loss of even a tiny fraction of the beam could cause a superconducting magnet to undergo a transition into a normal-conducting state, or in the worst case cause material damage. Hence a multistage collimation system has been installed in order to safely intercept high-amplitude beam protons before they are lost elsewhere. To guarantee adequate protection from the collimators, a detailed theoretical understanding is needed. This article presents results of numerical simulations of the distribution of beam losses around the LHC that have leaked out of the collimation system. The studies include tracking of protons through the fields of more than 5000 magnets in the 27 km LHC ring over hundreds of revolutions, and Monte Carlo simulations of particle-matter interactions both in collimators and machine elements being hit by escaping particles. The simulation results agree typically within a factor 2 with measurements of beam loss distributions from the previous LHC run. Considering the complex simulation, which must account for a very large number of unknown imperfections, and in view of the total losses around the ring spanning over 7 orders of magnitude, we consider this an excellent agreement. Our results give confidence in the simulation tools, which are used also for the design of future accelerators.

The LACARA Vacuum Laser Accelerator Experiment: Beam Positioning and Alignment in a Strong Magnetic Field

International Nuclear Information System (INIS)

Shchelkunov, Sergey V.; Marshall, T. C.; Hirshfield, J. L.; Wang, Changbiao; LaPointe, M. A.

2006-01-01

LACARA (laser cyclotron auto-resonance accelerator) is a vacuum laser accelerator of electrons that is under construction at the Accelerator Test Facility (ATF), Brookhaven National Laboratory. It is expected that the experiment will be assembled by September 2006; this paper presents progress towards this goal. According to numerical studies, as an electron bunch moves along the LACARA solenoidal magnetic field (∼5.2 T, length ∼1 m), it will be accelerated from 50 to ∼75 MeV by interacting with a 0.8 TW Gaussian-mode circularly polarized optical pulse provided by the ATF CO2 10.6μm laser system. The LACARA laser transport optics must handle 10 J and be capable of forming a Gaussian beam inside the solenoid with a 1.4 mm waist and a Rayleigh range of 60 cm. The electron optics must transport a bunch having input emittance of 0.015 mm-mrad and 100 μm waist through the magnet. Precision alignment between the electron beam and the solenoid magnetic axis is required, and a method to achieve this is described in detail. Emittance- filtering may be necessary to yield an accelerated bunch having a narrow (∼1%) energy-spread

Minimal interference beam size/profile measurement techniques applicable to the Collider

International Nuclear Information System (INIS)

Nexsen, W.; Dutt, S.; Kauffmann, S.; Lebedev, V.; Maschke, A.; Mokhov, N.; Richardson, R.; Tsyganov, E.; Zinchenko, A.

1993-05-01

The imaging of synchrotron radiation (SR) has been suggested as a technique for providing a continuous, non-interfering monitor of the beam profile in the Collider rings at the Superconducting Super Collider. A closer examination has raised questions concerning the applicability of SR imaging in this case because of the diffraction broadening of the image, the requirements for axial space and location in the lattice, and the complexity of the system. We have surveyed the known, alternative, minimal interference techniques for measuring beam size and have evaluated them for possible Collider usage. We conclude that of the approaches that appear feasible, all require at least some development for our usage and that the development of an electron beam probe offers the best promise. We recommend that flying wires be used for cross-checking and calibrating the electron beam probe diagnostic and for luminosity measurements when the highest accuracy is required, but flying wires should not be used as the primary diagnostic because of their limited lifetime

Proceedings of the international workshop on next-generation linear colliders

International Nuclear Information System (INIS)

Riordan, M.

1988-12-01

This report contains papers on the next-generation of linear colliders. The particular areas of discussion are: parameters; beam dynamics and wakefields; damping rings and sources; rf power sources; accelerator structures; instrumentation; final focus; and review of beam-beam interaction

Proceedings of the international workshop on next-generation linear colliders

Energy Technology Data Exchange (ETDEWEB)

Riordan, M. (ed.)

1988-12-01

This report contains papers on the next-generation of linear colliders. The particular areas of discussion are: parameters; beam dynamics and wakefields; damping rings and sources; rf power sources; accelerator structures; instrumentation; final focus; and review of beam-beam interaction.

Collider workshop

International Nuclear Information System (INIS)

Anon.

1982-01-01

The promise of initial results after the start of operations at CERN's SPS proton-antiproton collider and the prospects for high energy hadron collisions at Fermilab (Tevatron) and Brookhaven (ISABELLE) provided a timely impetus for the recent Topical Workshop on Forward Collider Physics', held at Madison, Wisconsin, from 10-12 December. It became the second such workshop to be held, the first having been in 1979 at the College de France, Paris. The 100 or so participants had the chance to hear preliminary results from the UA1, UA4 and UA5 experiments at the CERN SPS collider, together with other new data, including that from proton-antiproton runs at the CERN Intersecting Storage Rings

Lepton accelerators and radiation sources: R and D investment at BNL

International Nuclear Information System (INIS)

Ben-Zvi, I.; Fernow, R.; Gallardo, J.; Hart, M.; Hastings, J.; Johnson, E.; Krinsky, S.; Palmer, R.; Yu, L.H.

1997-03-01

Brookhaven National Laboratory (BNL) has shown its determination to remain at the forefront of accelerator based science through its continued investment in long range accelerator R and D. The laboratory has a broad program in accelerator technology development including projects such as high T c magnets at RHIC, Siberian Snakes at the AGS, brightness upgrades on the NSLS storage ring, and spallation source R and D in several departments. This report focuses on a segment of the overall program: the lepton accelerator and coherent radiation source R and D at the laboratory. These efforts are aimed at (1) development of high brightness electron beams, (2) novel acceleration techniques, (3) seeded Free Electron Laser (FEL) development, and (4) R and D for a muon collider. To pursue these objectives, BNL ha over the past decade introduced new organizational arrangements. The BNL Center for Accelerator Physics (CAP) is an interdepartmental unit dedicated to promoting R and D which, cannot be readily conducted within the programs of operating facilities. The Accelerator Test Facility (ATF) is managed by CAP and NSLS as a user facility dedicated to accelerator and beam physics problems of interest to both the High Energy Physics and Basic Energy Sciences programs of the DOE. Capitalizing on these efforts, the Source Development Laboratory (SDL) was established by the NSLS to facilitate coordinated development of sources and experiments to produce and utilize coherent sub-picosecond synchrotron radiation. This White Paper describes the programs being pursued at CAP, ATF and SDL aimed at advancing basic knowledge of lepton accelerators and picosecond radiation sources

Multi-beam linear accelerator EVT

Energy Technology Data Exchange (ETDEWEB)

Teryaev, Vladimir E., E-mail: vladimir_teryaev@mail.ru [Omega-P, Inc., New Haven, CT 06510 (United States); Kazakov, Sergey Yu. [Fermilab, Batavia, IL 60510 (United States); Hirshfield, Jay L. [Omega-P, Inc., New Haven, CT 06510 (United States); Yale University, New Haven, CT 06511 (United States)

2016-09-01

A novel electron multi-beam accelerator is presented. The accelerator, short-named EVT (Electron Voltage Transformer) belongs to the class of two-beam accelerators. It combines an RF generator and essentially an accelerator within the same vacuum envelope. Drive beam-lets and an accelerated beam are modulated in RF modulators and then bunches pass into an accelerating structure, comprising uncoupled with each other and inductive tuned cavities, where the energy transfer from the drive beams to the accelerated beam occurs. A phasing of bunches is solved by choice correspond distances between gaps of the adjacent cavities. Preliminary results of numerical simulations and the initial specification of EVT operating in S-band, with a 60 kV gun and generating a 2.7 A, 1.1 MV beam at its output is presented. A relatively high efficiency of 67% and high design average power suggest that EVT can find its use in industrial applications.

Beam dynamics in a TeV linear collider

International Nuclear Information System (INIS)

Yokoya, Kaoru

1984-01-01

The author's group at KEK has investigated the feasibility of an electron-positron linear collider of 1x1 TeV region using the Lasertron. In this report, three major problems are discussed. That is, beam-beam interaction; beam instability in the linac; and the damping ring. As the most important parameter, the luminosity of the linear collider is analyzed, taking into account the pinch effect and the beamstrahlung. The problems in the development of final focusing system are also considered. As for the wake field in the linac, the transverse wake field is more important than the longitudinal one. The misalignment of cavity is discussed as a cause of inducing the transverse wake field. Finally, the design requirement for the damping ring is considered, and the values of some important design parameters are given: These include energy, radius, bending radius, number of bunch, transverse damping time, natural emittance, vertical-horizontal coupling, the time constant of extraction kicker, and the structure of the FODO cell. (Aoki, K.)

Technical challenge of future linear colliders

International Nuclear Information System (INIS)

Himel, T.

1986-05-01

The next generation of high energy e + e - colliders is likely to be built with colliding linear accelerators. A lot of research and development is needed before such a machine can be practically built. Some of the problems and recent progress made toward their solution are described here. Quantum corrections to beamstrahlung, the production of low emittance beams and strong focusing techniques are covered

Polarized Electrons for Linear Colliders

International Nuclear Information System (INIS)

Clendenin, J.

2004-01-01

Future electron-positron linear colliders require a highly polarized electron beam with a pulse structure that depends primarily on whether the acceleration utilizes warm or superconducting rf structures. The International Linear Collider (ILC) will use cold structures for the main linac. It is shown that a dc-biased polarized photoelectron source such as successfully used for the SLC can meet the charge requirements for the ILC micropulse with a polarization approaching 90%

Wakefield and Beam Centering Measurements of a Damped and Detuned X-Band Accelerator Structure

International Nuclear Information System (INIS)

Adolphsen, Chris

1999-01-01

In the Next Linear Collider (NLC) design, X-Band (11.4 GHz) accelerator structures are used to accelerate multibunch beams to several hundred GeV. Although these structures allow for high gradient operation, their strong deflecting modes impose a number of operational constraints. In particular, the long-range transverse wakefields generated by the bunches need to be reduced by about two orders of magnitude to prevent significant beam breakup. During the past five years, a reduction scheme that employs both detuning and damping of the structure dipole modes has been developed to meet this requirement. Several prototype Damped and Detuned Structures (DDS) have been built to test and refine this scheme. The wakefield of the latest version, DDS3, has recently been measured in the Accelerator Structure Setup (ASSET) facility at SLAC. In this paper, we present these results together with predictions based on an equivalent circuit model of the structure. We also present ASSET studies in which the beam-induced dipole signals that are coupled out for damping purposes are used to center the beam in the structure

Thermomechanical response of Large Hadron Collider collimators to proton and ion beam impacts

Directory of Open Access Journals (Sweden)

Marija Cauchi

2015-04-01

Full Text Available The CERN Large Hadron Collider (LHC is designed to accelerate and bring into collision high-energy protons as well as heavy ions. Accidents involving direct beam impacts on collimators can happen in both cases. The LHC collimation system is designed to handle the demanding requirements of high-intensity proton beams. Although proton beams have 100 times higher beam power than the nominal LHC lead ion beams, specific problems might arise in case of ion losses due to different particle-collimator interaction mechanisms when compared to protons. This paper investigates and compares direct ion and proton beam impacts on collimators, in particular tertiary collimators (TCTs, made of the tungsten heavy alloy INERMET® 180. Recent measurements of the mechanical behavior of this alloy under static and dynamic loading conditions at different temperatures have been done and used for realistic estimates of the collimator response to beam impact. Using these new measurements, a numerical finite element method (FEM approach is presented in this paper. Sequential fast-transient thermostructural analyses are performed in the elastic-plastic domain in order to evaluate and compare the thermomechanical response of TCTs in case of critical beam load cases involving proton and heavy ion beam impacts.

Cavity beam position monitor system for the Accelerator Test Facility 2

Directory of Open Access Journals (Sweden)

Y. I. Kim

2012-04-01

Full Text Available The Accelerator Test Facility 2 (ATF2 is a scaled demonstrator system for final focus beam lines of linear high energy colliders. This paper describes the high resolution cavity beam position monitor (BPM system, which is a part of the ATF2 diagnostics. Two types of cavity BPMs are used, C-band operating at 6.423 GHz, and S-band at 2.888 GHz with an increased beam aperture. The cavities, electronics, and digital processing are described. The resolution of the C-band system with attenuators was determined to be approximately 250 nm and 1  μm for the S-band system. Without attenuation the best recorded C-band cavity resolution was 27 nm.

ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.

Energy Technology Data Exchange (ETDEWEB)

ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; GRANDINETTI, R.; HSEUH, H.; JAVIDFAR, A.; KPONOU, A.; LAMBIASE, R.; LESSARD, E.; LOCKEY, R.; LODESTRO, V.; MAPES, M.; MIRABELLA, D.; NEHRING, T.; OERTER, B.; PENDZICK, A.; PIKIN, A.; RAPARIA, D.; RITTER, J.; ROSER, T.; RUSSO, T.; SNYDSTRUP, L.; WILINSKI, M.; ZALTSMAN, A.; ZHANG, S.

2005-09-01

This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linear accelerator (Linac). The highly successful development of an EBIS at Brookhaven National Laboratory (BNL) now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based preinjectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The proposed pre-injector system would also provide for a major enhancement in capability for the NASA Space Radiation Laboratory (NSRL), which utilizes heavy-ion beams from the RHIC complex. EBIS would allow for the acceleration of all important ion species for the NASA radiobiology program, such as, helium, argon, and neon which are unavailable with the present Tandem injector. In addition, the new system would allow for very rapid switching of ion species for

RF linear accelerators

CERN Document Server

Wangler, Thomas P

2008-01-01

Thomas P. Wangler received his B.S. degree in physics from Michigan State University, and his Ph.D. degree in physics and astronomy from the University of Wisconsin. After postdoctoral appointments at the University of Wisconsin and Brookhaven National Laboratory, he joined the staff of Argonne National Laboratory in 1966, working in the fields of experimental high-energy physics and accelerator physics. He joined the Accelerator Technology Division at Los Alamos National Laboratory in 1979, where he specialized in high-current beam physics and linear accelerator design and technology. In 2007

Relativistic Klystron Two-Beam Accelerator studies at the RTA test facility

International Nuclear Information System (INIS)

Westenskow, G.A.; Houck, T.L.; Anderson, D.

1996-01-01

A prototype rf power source based on the Relativistic Klystron Two- Beam Accelerator (RK-TBA) concept is being constructed at LBNL to study physics, engineering, and costing issues. The prototype, called RTA, is described and compared to a full scale design appropriate for driving the Next Linear Collider. Specific details of the induction core test and pulsed power system are presented. Details of the 1-MeV, 1.2-kA induction gun currently under construction are described

Perspectives on large linear colliders

International Nuclear Information System (INIS)

Richter, B.

1987-11-01

Three main items in the design of large linear colliders are presented. The first is the interrelation of energy and luminosity requirements. These two items impose severe constraints on the accelerator builder who must design a machine to meet the needs of experimentl high energy physics rather than designing a machine for its own sake. An introduction is also given for linear collider design, concentrating on what goes on at the collision point, for still another constraint comes here from the beam-beam interaction which further restricts the choices available to the accelerator builder. The author also gives his impressions of the state of the technology available for building these kinds of machines within the next decade. The paper concludes with a brief recommendation for how we can all get on with the work faster, and hope to realize these machines sooner by working together. 10 refs., 9 figs

Femtosecond planar electron beam source for micron-scale dielectric wake field accelerator

Directory of Open Access Journals (Sweden)

T. C. Marshall

2001-12-01

Full Text Available A new accelerator, LACARA (laser-driven cyclotron autoresonance accelerator, under construction at the Accelerator Test Facility at Brookhaven National Laboratory, is to be powered by a 1 TW CO_{2} laser beam and a 50 MeV injected electron pulse. LACARA will produce inside a 2 m, 6 T solenoid a 100 MeV gyrating electron bunch, with ∼3% energy spread, approximately 1 psec in length with particles advancing in phase at the laser frequency, executing one cycle each 35 fsec. A beamstop with a small off axis channel will transmit a short beam pulse every optical cycle, thereby producing a train of about 30, 3.5 fsec long, 1–3 pC microbunches for each laser pulse. We describe here a novel accelerator, a micron-scale dielectric wake field accelerator driven by a 500 MeV LACARA-type injector that takes the output train of microbunches and transforms them into a near-rectangular cross section having a narrow dimension of ∼10 μm and height of ∼150 μm using a magnetic quadrupole; these bunches may be injected into a planar dielectric-lined waveguide (slightly larger than the bunch where cumulative buildup of wake fields can lead to an accelerating gradient >1 GV/m. This proposed vacuum-based wake field structure is physically rigid and capable of microfabrication accuracy, factors important in staging a large number of accelerator modules. Furthermore, the accelerating gradients it promises are comparable with those for plasma accelerators. A LACARA unit for preparing suitable bunches at 500 MeV is described. Physics issues are discussed, including bunch spreading and transport, bunch shaping, coherent diffraction radiation from the aperture, dielectric breakdown, and bunch stability in the rectangular wake field structure.

Beam Tests of a New Digital Beam Control System for the CERN LEIR Accelerator

CERN Document Server

Angoletta, Maria Elena; Blas, Alfred; De Long, Joseph; Findlay, Alan; Matuszkiewicz, Pawel; Pedersen, Flemming; Salom-Sarasqueta, Angela

2005-01-01

The Low Energy Ion Ring (LEIR) is a major component in the Large Hadron Collider ion injector chain. We have been developing an all-digital beam control and cavity servo system for the RF acceleration in LEIR. The system is housed by VME motherboards that may hold various daughter boards. Fast tasks are executed in Field Programmable Gate Arrays (FPGAs), slower tasks and communication with the software layer above are achieved in Digital Signal Processors (DSPs). We describe a simplified system prototype, which we tested with low intensity beams on the CERN PS Booster (PSB). The aim was to verify the combined DSP+FPGA architecture and the feedback loop dynamics. An additional goal was to deploy and validate novel software concepts, such as reference-functions and timings generation, and user-selectable digital data acquisition.

Muon Colliders: the Ultimate Neutrino Beamlines

International Nuclear Information System (INIS)

King, Bruce J.

1999-01-01

It is shown that muon decays in straight sections of muon collider rings will naturally produce highly collimated neutrino beams that can be several orders of magnitude stronger than the beams at existing accelerators. We discuss possible experimental setups and give a very brief overview of the physics potential from such beamlines. Formulae are given for the neutrino event rates at both short and long baseline neutrino experiments in these beams

VLHC accelerator physics

Energy Technology Data Exchange (ETDEWEB)

Michael Blaskiewicz et al.

2001-11-01

A six-month design study for a future high energy hadron collider was initiated by the Fermilab director in October 2000. The request was to study a staged approach where a large circumference tunnel is built that initially would house a low field ({approx}2 T) collider with center-of-mass energy greater than 30 TeV and a peak (initial) luminosity of 10{sup 34} cm{sup -2}s{sup -1}. The tunnel was to be scoped, however, to support a future upgrade to a center-of-mass energy greater than 150 TeV with a peak luminosity of 2 x 10{sup 34} cm{sup -2} sec{sup -1} using high field ({approx} 10 T) superconducting magnet technology. In a collaboration with Brookhaven National Laboratory and Lawrence Berkeley National Laboratory, a report of the Design Study was produced by Fermilab in June 2001. 1 The Design Study focused on a Stage 1, 20 x 20 TeV collider using a 2-in-1 transmission line magnet and leads to a Stage 2, 87.5 x 87.5 TeV collider using 10 T Nb{sub 3}Sn magnet technology. The article that follows is a compilation of accelerator physics designs and computational results which contributed to the Design Study. Many of the parameters found in this report evolved during the study, and thus slight differences between this text and the Design Study report can be found. The present text, however, presents the major accelerator physics issues of the Very Large Hadron Collider as examined by the Design Study collaboration and provides a basis for discussion and further studies of VLHC accelerator parameters and design philosophies.

High intensity proton acceleration at the Brookhaven AGS -- An update

International Nuclear Information System (INIS)

Ahrens, L.; Alessi, J.; Blaskiewicz, M.

1997-01-01

The AGS accelerator complex is into its third year of 60+ x 10 12 (teraproton = Tp) per cycle operation. The hardware making up the complex as configured in 1997 is briefly mentioned. The present level of accelerator performance is discussed. This includes beam transfer efficiencies at each step in the acceleration process, i.e. losses; which are a serious issue at this intensity level. Progress made in understanding beam behavior at the Linac-to-Booster (LtB) injection, at the Booster-to-AGS (BtA) transfer as well as across the 450 ms AGS accumulation porch is presented. The state of transition crossing, with the gamma-tr jump is described. Coherent effects including those driven by space charge are important at all of these steps

Linear beam-beam tune shift calculations for the Tevatron Collider

International Nuclear Information System (INIS)

Johnson, D.

1989-01-01

A realistic estimate of the linear beam-beam tune shift is necessary for the selection of an optimum working point in the tune diagram. Estimates of the beam-beam tune shift using the ''Round Beam Approximation'' (RBA) have over estimated the tune shift for the Tevatron. For a hadron machine with unequal lattice functions and beam sizes, an explicit calculation using the beam size at the crossings is required. Calculations for various Tevatron lattices used in Collider operation are presented. Comparisons between the RBA and the explicit calculation, for elliptical beams, are presented. This paper discusses the calculation of the linear tune shift using the program SYNCH. Selection of a working point is discussed. The magnitude of the tune shift is influenced by the choice of crossing points in the lattice as determined by the pbar ''cogging effects''. Also discussed is current cogging procedures and presents results of calculations for tune shifts at various crossing points in the lattice. Finally, a comparison of early pbar tune measurements with the present linear tune shift calculations is presented. 17 refs., 13 figs., 3 tabs

Perspectives on large Linear Colliders

International Nuclear Information System (INIS)

Richter, B.

1987-01-01

The accelerator community now generally agrees that the Linear Collider is the most cost-effective technology for reaching much higher energies in the center-of-mass than can be attained in the largest of the e + e - storage rings, LEP. Indeed, even as the first linear collider, the SLC at SLAC, is getting ready to begin operations groups, at SLAC, Novosibirsk, CERN and KEK are doing R and D and conceptual design studies on a next generation machine in the 1 TeV energy region. In this perspectives talk I do not want to restrict my comments to any particular design, and so I will talk about a high-energy machine as the NLC, which is shorthand for the Next Linear Collider, and taken to mean a machine with a center-of-mass energy someplace in the 0.5 to 2 TeV energy range with sufficient luminosity to carry out a meaningful experimental program. I want to discuss three main items with you. The first is the interrelation of energy and luminosity requirements. These two items impose severe constraints on the accelerator builder. Next, I will give an introduction to linear collider design, concentrating on what goes on at the collision point, for still another constraint comes here from the beam-beam interaction which further restricts the choices available to the accelerator builder.Then, I want to give my impressions of the state of the technology available for building these kinds of machines within the next decade

CLIC, a 0.5 to 5 TeV e$^{\\pm}$ Compact Linear Collider

CERN Document Server

Delahaye, J P; Braun, Hans Heinrich; Carron, G; Chautard, F; Coosemans, Williame; Corsini, R; D'Amico, T E; Dehler, M; Godot, J C; Guignard, Gilbert; Hagel, J; Hutchins, S; Johnson, C D; Jensen, E; Kamber, I; Millich, Antonio; Pearce, P; Potier, J P; Riche, A J; Rinolfi, Louis; Schulte, Daniel; Suberlucq, Guy; Thorndahl, L; Valentini, M; Warner, D J; Wilson, Ian H; Wuensch, Walter; Napoly, O; Raubenheimer, T O; Ruth, Ronald D

1998-01-01

The CLIC study of a high energy (0.5 - 5 TeV), high luminosity (10^34 - 10^35 cm^-2 sec^-1) e± linear collider is presented. Beam acceleration using high frequency (30 GHz) normal-conducting structure s operating at high accelerating fields (100 to 200 MV/m) significantly reduces the length and, in consequence the cost of the linac. Based on new beam and linac parameters derived from a recently dev eloped set of general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. A new cost effe ctive and very efficient drive beam generation scheme for RF power production by the so-called "Two Beam Acceleration (TBA)" method is described. It uses a conventional thermionic gun and a fully-load ed normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches and RF multiplication by funneling in compressor rings to produce the desired bunch st ructure. Recent 30...

Asymmetric collider

International Nuclear Information System (INIS)

Bharadwaj, V.; Colestock, P.; Goderre, G.; Johnson, D.; Martin, P.; Holt, J.; Kaplan, D.

1993-01-01

The study of CP violation in beauty decay is one of the key challenges facing high energy physics. Much work has not yielded a definitive answer how this study might best be performed. However, one clear conclusion is that new accelerator facilities are needed. Proposals include experiments at asymmetric electron-positron colliders and in fixed-target and collider modes at LHC and SSC. Fixed-target and collider experiments at existing accelerators, while they might succeed in a first observation of the effect, will not be adequate to study it thoroughly. Giomataris has emphasized the potential of a new approach to the study of beauty CP violation: the asymmetric proton collider. Such a collider might be realized by the construction of a small storage ring intersecting an existing or soon-to-exist large synchrotron, or by arranging collisions between a large synchrotron and its injector. An experiment at such a collider can combine the advantages of fixed-target-like spectrometer geometry, facilitating triggering, particle identification and the instrumentation of a large acceptance, while the increased √s can provide a factor > 100 increase in beauty-production cross section compared to Tevatron or HERA fixed-target. Beams crossing at a non-zero angle can provide a small interaction region, permitting a first-level decay-vertex trigger to be implemented. To achieve large √s with a large Lorentz boost and high luminosity, the most favorable venue is the high-energy booster (HEB) at the SSC Laboratory, though the CERN SPS and Fermilab Tevatron are also worth considering

Review of accelerator instrumentation

International Nuclear Information System (INIS)

Pellegrin, J.L.

1980-05-01

Some of the problems associated with the monitoring of accelerator beams, particularly storage rings' beams, are reviewed along with their most common solutions. The various electrode structures used for the measurement of beam current, beam position, and the detection of the bunches' transverse oscillations, yield pulses with sub-nanosecond widths. The electronics for the processing of these short pulses involves wide band techniques and circuits usually not readily available from industry or the integrated circuit market: passive or active, successive integrations, linear gating, sample-and-hold circuits with nanosecond acquisition time, etc. This report also presents the work performed recently for monitoring the ultrashort beams of colliding linear accelerators or single-pass colliders. To minimize the beam emittance, the beam position must be measured with a high resolution, and digitized on a pulse-to-pulse basis. Experimental results obtained with the Stanford two-mile Linac single bunches are included

Fixed-Target Electron Accelerators

International Nuclear Information System (INIS)

Brooks, William K.

2001-01-01

A tremendous amount of scientific insight has been garnered over the past half-century by using particle accelerators to study physical systems of sub-atomic dimensions. These giant instruments begin with particles at rest, then greatly increase their energy of motion, forming a narrow trajectory or beam of particles. In fixed-target accelerators, the particle beam impacts upon a stationary sample or target which contains or produces the sub-atomic system being studied. This is in distinction to colliders, where two beams are produced and are steered into each other so that their constituent particles can collide. The acceleration process always relies on the particle being accelerated having an electric charge; however, both the details of producing the beam and the classes of scientific investigations possible vary widely with the specific type of particle being accelerated. This article discusses fixed-target accelerators which produce beams of electrons, the lightest charged particle. As detailed in the report, the beam energy has a close connection with the size of the physical system studied. Here a useful unit of energy is a GeV, i.e., a giga electron-volt. (ne GeV, the energy an electron would have if accelerated through a billion volts, is equal to 1.6 x 10 -10 joules.) To study systems on a distance scale much smaller than an atomic nucleus requires beam energies ranging from a few GeV up to hundreds of GeV and more

High gradient experiment by accelerator test facility for Japan Linear Collider

International Nuclear Information System (INIS)

Takeda, Seishi; Akemoto, Mitsuo; Hayano, Hitoshi; Naito, Takashi; Matsumoto, Hiroshi

1991-01-01

For the e + e - linear colliders in TeV energy region such as the Japan Linear Collider (JLC), the accelerating gradient will be one of the important parameters affecting the over all design of main linacs. The gradient determines the accelerating structures, RF frequencies, peak power, AC power, total length and cost. High gradient experiment by using a traveling wave structure in S-band frequencies is presented. Discussions are given about the dependence of dark current and structure length. As one of the parameters indicating the quality of the structure, the multiplication factor η has been proposed

Upgrades of the epithermal neutron beam at the Brookhaven Medical Research Reactor

Energy Technology Data Exchange (ETDEWEB)

Liu, Hungyuan B.; Brugger, R.M.; Rorer, D.C.

1994-12-31

The first epithermal neutron beam at the Brookhaven Medical Research Reactor (BMRR) was installed in 1988 and produced a neutron beam that was satisfactory for the development of NCT with epithermal neutrons. This beam was used routinely until 1992 when the beam was upgraded by rearranging fuel elements in the reactor core to achieve a 50% increase in usable flux. Next, after computer modeling studies, it was proposed that the Al and Al{sub 2}O{sub 3} moderator material in the shutter that produced the epithermal neutrons could be rearranged to enhance the beam further. However, this modification was not started because a better option appeared, namely to use fission plates to move the source of fission neutrons closer to the moderator and the patient irradiation position to achieve more efficient moderation and production of epithermal neutrons. A fission plate converter (FPC) source has been designed recently and, to test the concept, implementation of this upgrade has started. The predicted beam parameters will be 12 x 10{sup 9} n{sub epi}/cm{sup 2}sec accompanying with doses from fast neutrons and gamma rays per epithermal neutron of 2.8 x 10{sup -11} and < 1 x 10{sup -11} cGycm{sup 2}/n, respectively, and a current-to-flux ratio of epithermal neutrons of 0.78. This conversion could be completed by late 1996.

A 200 MHz 35 MW Multiple Beam Klystron for Accelerator Applications. Final Report

International Nuclear Information System (INIS)

Ives, R. Lawrence; Read, Michael; Ferguson, Patrick; Marsden, David

2011-01-01

Calabazas Creek Research, Inc. (CCR) performed initial development of a compact and reliable 35 MW, multiple beam klystron (MBK) at 200 MHz with a pulse length of 0.125 ms and a 30 Hz repetition rate. The device was targeted for acceleration and ionization cooling of a muon collider, but there are several other potential applications in this frequency range. The klystron uses multiple beams propagating in individual beam tunnels to reduce space charge and allow reduction in the accelerating voltage. This allows a significant reduction in length over a single beam source. More importantly this allows more efficient and less expensive power supplies. At 200 MHz, the interaction circuit for a single beam klystron would be more than six meters long to obtain 50% efficiency and 50 dB gain. This would require a beam voltage of approximately 400 kV and current of 251 A for a microperveance of 1.0. For an eight beam MBK with the same beam perveance, a three meter long interaction circuit achieves the same power and gain. Each beam operates at 142 kV and 70A. The Phase I demonstrated that this device could be fabricated with funding available in a Phase II program and could achieve the program specifications.

KEK plans for a linear collider R ampersand D

International Nuclear Information System (INIS)

Horikoshi, G.; Kimura, Y.; Nishikawa, T.

1989-01-01

An overall R ampersand D activities of Japanese Linear Collider (JLC) is surveyed. The JLC is a conceptual plan of post TRISTAN projects in KEK. This is a large linear collider consisting of a pair of linear accelerators of 0.5 TeV each (for electron and positron), and a pair of damping rings. As a preliminary work, an R ampersand D group is promoting the Test Accelerator Facility (TAF) as a pilot plan. The TAF consists of a linear accelerator with an energy of 1.5 GeV and a damping ring, and will be used for the beam acceleration test with a high gradient of 100 MV/m. An R ampersand D on the high Tc superconducting thin film is also underway to investigate possible application to the RF accelerating structure for the superconducting linear collider. 11 refs., 7 figs., 1 tab

Low-field permanent magnet quadrupoles in a new relativistic-klystron two-beam accelerator design

Energy Technology Data Exchange (ETDEWEB)

Yu, S.; Sessler, A. [Lawrence Berkeley Lab., CA (United States)

1995-02-01

Permanent magnets play a central role in the new relativistic klystron two-beam-accelerator design. The two key goals of this new design, low cost and the suppression of beam break-up instability are both intimately tied to the permanent magnet quadrupole focusing system. A recently completed systems study by a joint LBL-LLNL team concludes that a power source for a 1 TeV center-of-mass Next Linear Collider based on the new TBA design can be as low as $1 billion, and the efficiency (wall plug to rf) is estimated to be 36%. End-to-end simulations of longitudinal and transverse beam dynamics show that the drive beam is stable over the entire TBA unit.

Scintillation chamber of calorimeters for colliding beam detectors

International Nuclear Information System (INIS)

Jones, L.W.

1983-01-01

It is suggested that the scintillation chamber, a technique first discussed almost thirty years ago, might find application in colliding beam detector systems, in particular as a means of efficiently extracting detailed spatial and energy information from a sampling calorimeter

E-Beam Driven Accelerators: Working Group Summary

International Nuclear Information System (INIS)

Muggli, P.; Southern California U.; Ng, J.S.T.; SLAC

2005-01-01

The working group has identified the parameters of an afterburner based on the design of a future linear collider. The new design brings the center of mass energy of the collider from 1 to 2 TeV. The afterburner is located in the final focus section of the collider, operates at a gradient of ∼4 GeV/m, and is only about 125 m long. Very important issues remain to be addressed, and include the physics and design of the positron side of the afterburner, as well as of the final focus system. Present plasma wakefield accelerator experiments have reached a level of maturity and of relevance to the afterburner, that make it timely to involve the high energy physics and accelerator community in the afterburner design process. The main result of this working group is the first integration of the designs of a future linear collider and an afterburner

Development of a Laser-based Emittance Monitor for Negative Hydrogen Beams

CERN Document Server

AUTHOR|(CDS)2078368; Schmauss, Bernhard; Gibson, Stephen; Boorman, Gary; Bosco, Alessio

High energy particle accelerators are designed to collide charged particle beams and thus study the collision products. Maximising the collision rate, to generate sufficient statistics for precise measurements of rare processes, is one of the key parameters for optimising the overall collider performance. The CERN Large Hadron Collider (LHC) Injectors Upgrade (LIU) includes the construction of LINAC4, a completely new machine working as a first linear acceleration stage for the LHC beam. By accelerating a negative hydrogen beam (H-) instead of protons, it aims to double the beam brightness via a more efficient transfer to the first circular accelerator and subsequently boost the LHC collision rate. To achieve this, a precise knowledge of the transverse beam characteristics in terms of beam emittance is essential. This thesis work covers the development of a laser-based monitor meant to measure non-destructively the LINAC4 beam transverse profile and emittance. This included the implementation of dif...

The charged beam dumps for the international linear collider

CERN Document Server

Appleby, R; Broome, T; Densham, C; Vincke, H

2006-01-01

The baseline configuration of the International Linear Collider requires 2 beam dumps per interaction region, each rated to 18MW of beam power, together with additional beam dumps for tuning purposes and machine protection. The baseline design uses high pressure moving water dumps, first developed for the SLC and used in the TESLA design, although a gas based dump is also being considered. In this paper we discuss the progress made by the international community on both physics and engineering studies for the beam dumps.

Scraping beam halo in {mu} {sup +} {mu} {sup minus} colliders

Energy Technology Data Exchange (ETDEWEB)

Drozhdin, A.; Mokhov, N.; Johnstone, C.; Wan, W.; Garren, A.

1998-01-01

Beam halo scraping schemes have been explored in the 50 x 50 GeV and 2 x 2 TeV {mu}{sup +}{mu}{sup -} colliders using both absorbers and electrostatic deflectors. Utility sections have been specially designed into the rings for scraping. Results of realistic STRUCT- MARS Monte-Carlo simulations show that for the low-energy machine a scheme with a 5 m long steel absorber suppresses losses in the interaction region by three orders of magnitude. The same scraping efficiency at 2 TeV is achieved only by complete extraction of beam halo from the machine. The effect of beam-induced power dissipation in the collider superconducting magnets and detector backgrounds is shown both for the first few turns after injection and for the rest of the cycle.

Muon Muon Collider: Feasibility Study

Energy Technology Data Exchange (ETDEWEB)

Gallardo, J.C.; Palmer, R.B.; /Brookhaven; Tollestrup, A.V.; /Fermilab; Sessler, A.M.; /LBL, Berkeley; Skrinsky, A.N.; /Novosibirsk, IYF; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. /Fermilab /Brookhaven /Wisconsin U., Madison /Tel Aviv U. /Indiana U. /UCLA /LBL, Berkeley /SLAC /Argonne /Sobolev IM, Novosibirsk /UC, Davis /Munich, Tech. U. /Virginia U. /KEK, Tsukuba /DESY /Novosibirsk, IYF /Jefferson Lab /Mississippi U. /SUNY, Stony Brook /MIT /Columbia U. /Fairfield U. /UC, Berkeley

2012-04-05

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle

Structural behavior of cable superconductors

International Nuclear Information System (INIS)

Becker, H.; Marston, P.

1983-01-01

The structural properties of cable superconductor coils, for particle accelerators such as the Tevatron and the CBA (Colliding Beam Accelerator), depend upon direction of loading. For compression perpendicular to the ''flat faces'' of the conductor, the coils exhibit nonlinear, inelastic and time dependent behavior. The same is true for ''inplane'' compression loading perpendicular to the conductor edges. In the lengthwise direction, the coils display tension and compression stress-strain curves typical of structural metals. The loading of primary concern is compression perpendicular to the conductor faces since deformations in that direction can have a major influence on magnetic field quality. However, the coil behavior under that condition is uncertain because of the nonlinear stress strain curve complicated by creep and relaxation at the stress levels induced by preloading and Lorentz forces. Furthermore, the stiffness of the loading fixture appears to influence the data as shown by results from tests run under different conditions at Berkeley, Brookhaven and MIT. The paper displays test data on stress-strain curves for all three loading directions. Results are presented for RT, 77 K and 4 K behavior. Data of various investigators are compared. The applicability of a relatively simple power law between stress and strain is depicted

Simulations of the TESLA Linear Collider with a Fast Feedback System

CERN Document Server

Schulte, Daniel; White, G

2003-01-01

The tolerances on the beams as they collide at the interaction point of the TESLA linear collider are very tight due to the nano-metre scale final vertical bunch spot sizes. Ground motion causes the beams to increase in emittance and drift out of collision leading to dramatic degradation of luminosity performance. To combat this, both slow orbit and fast intra-train feedback systems will be used. The design of these feedback systems depends critically on how component misalignment effects the beam throughout the whole accelerator. A simulation has been set up to study in detail the accelerator performance under such conditions by merging the codes of PLACET, MERLIN and GUINEA-PIG together with Simulink code to model feedback systems, all under a Matlab environment.

Linear collider IR and final focus introduction

International Nuclear Information System (INIS)

Irwin, J.; Burke, D.

1991-09-01

The Linear Collider subgroup of the Accelerator Physics working group concerned itself with all aspects of the Next Linear Collider (NLC) design from the end of the accelerating structure to and through the interaction region. Within this region are: (1) a collimation section, (2) muon protection (of the detector from the collimator), (3) final focus system, (4) interaction point physics, and (5) detector masking from synchrotron radiation and beam-beam pair production. These areas of study are indicated schematically in Fig. 1. The parameters for the Next Linear Collider are still in motion, but attention has settled on a handful of parameter sets. Energies under consideration vary from 0.5 to 1.5 TeV in the center of mass, and luminosities vary from 10 33 to 10 34 cm -2 s -1 . To be concrete we chose as a guide for our studies the parameter sets labeled F and G, Table 1 from Palmer. These cover large and small crossing angle cases and 0.4 m to 1.8 m of free length at the interaction point

BROOKHAVEN: High energy gold

International Nuclear Information System (INIS)

Bleser, Ed

1992-01-01

On April 24, Brookhaven's Alternating Gradient Synchrotron (AGS) started to deliver gold ions at 11.4 GeV per nucleon (2,000 GeV per ion) to experimenters who were delighted not only to receive the world's highest energy gold beam but also to receive it on schedule

High-brightness electron beam diagnostics at the ATF

International Nuclear Information System (INIS)

Wang, X.J.; Ben-Zvi, I.

1996-01-01

The Brookhaven Accelerator Test Facility (ATF) is a dedicated user facility for accelerator physicists. Its design is optimized to explore laser acceleration and coherent radiation production. To characterize the low-emittance, picoseconds long electron beam produced by the ATF's photocathode RF gun, we have installed electron beam profile monitors for transverse emittance measurement, and developed a new technique to measure electron beam pulse length by chirping the electron beam energy. We have also developed a new technique to measure the ps slice emittance of a 10 ps long electron beam. Stripline beam position monitors were installed along the beam to monitor the electron beam position and intensity. A stripline beam position monitor was also used to monitor the timing jitter between the RF system and laser pulses. Transition radiation was used to measure electron beam energy, beam profile and electron beam bunch length

Concepts and techniques: Active electronics and computers in safety-critical accelerator operation

International Nuclear Information System (INIS)

Frankel, R.S.

1995-01-01

The Relativistic Heavy Ion Collider (RHIC) under construction at Brookhaven National Laboratory, requires an extensive Access Control System to protect personnel from Radiation, Oxygen Deficiency and Electrical hazards. In addition, the complicated nature of operation of the Collider as part of a complex of other Accelerators necessitates the use of active electronic measurement circuitry to ensure compliance with established Operational Safety Limits. Solutions were devised which permit the use of modern computer and interconnections technology for Safety-Critical applications, while preserving and enhancing, tried and proven protection methods. In addition a set of Guidelines, regarding required performance for Accelerator Safety Systems and a Handbook of design criteria and rules were developed to assist future system designers and to provide a framework for internal review and regulation

Concepts and techniques: Active electronics and computers in safety-critical accelerator operation

Energy Technology Data Exchange (ETDEWEB)

Frankel, R.S.

1995-12-31

The Relativistic Heavy Ion Collider (RHIC) under construction at Brookhaven National Laboratory, requires an extensive Access Control System to protect personnel from Radiation, Oxygen Deficiency and Electrical hazards. In addition, the complicated nature of operation of the Collider as part of a complex of other Accelerators necessitates the use of active electronic measurement circuitry to ensure compliance with established Operational Safety Limits. Solutions were devised which permit the use of modern computer and interconnections technology for Safety-Critical applications, while preserving and enhancing, tried and proven protection methods. In addition a set of Guidelines, regarding required performance for Accelerator Safety Systems and a Handbook of design criteria and rules were developed to assist future system designers and to provide a framework for internal review and regulation.

Determination of Beam Intensity and Position in a Particle Accelerator

CERN Document Server

Kasprowicz, Grzegorz

2010-01-01

The Proton Synchrotron accelerator (PS), installed at CERN, although commissioned in 1959, still plays a central role in the production of beams for the Antiproton Decelerator, Super Proton Synchrotron, various experimental areas and for the Large Hadron Collider (LHC). The PS produces beams of different types of particles, mainly protons, but also various species of ions. Almost all these particle beams pass through the PS. The quality of the beams delivered to the LHC has a direct impact on the effective luminosity, and therefore the performance of the instrumentation of the PS is of great importance. The old trajec- tory and orbit measurement system of the PS dated back to 1988 and no longer fulfilled present day requirements. It used 40 beam position monitors (BPMs) and an analogue signal processing chain to acquire the trajectory of one single particle bunch out of many, over two consecutive turns at a maximum rate of once every 5ms. The BPMs were in good condition, however the electronics was aging and ...

Radio Frequency Station - Beam Dynamics Interaction in Circular Accelerators

Energy Technology Data Exchange (ETDEWEB)

Mastoridis, Themistoklis [Stanford Univ., CA (United States)

2010-08-01

The longitudinal beam dynamics in circular accelerators is mainly defined by the interaction of the beam current with the accelerating Radio Frequency (RF) stations. For stable operation, Low Level RF (LLRF) feedback systems are employed to reduce coherent instabilities and regulate the accelerating voltage. The LLRF system design has implications for the dynamics and stability of the closed-loop RF systems as well as for the particle beam, and is very sensitive to the operating range of accelerator currents and energies. Stability of the RF loop and the beam are necessary conditions for reliable machine operation. This dissertation describes theoretical formalisms and models that determine the longitudinal beam dynamics based on the LLRF implementation, time domain simulations that capture the dynamic behavior of the RF station-beam interaction, and measurements from the Positron-Electron Project (PEP-II) and the Large Hadron Collider (LHC) that validate the models and simulations. These models and simulations are structured to capture the technical characteristics of the system (noise contributions, non-linear elements, and more). As such, they provide useful results and insight for the development and design of future LLRF feedback systems. They also provide the opportunity to study diverse longitudinal beam dynamics effects such as coupled-bunch impedance driven instabilities and single bunch longitudinal emittance growth. Coupled-bunch instabilities and RF station power were the performance limiting effects for PEP-II. The sensitivity of the instabilities to individual LLRF parameters, the effectiveness of alternative operational algorithms, and the possible tradeoffs between RF loop and beam stability were studied. New algorithms were implemented, with significant performance improvement leading to a world record current during the last PEP-II run of 3212 mA for the Low Energy Ring. Longitudinal beam emittance growth due to RF noise is a major concern for LHC

Beam-beam phenomenology

International Nuclear Information System (INIS)

Teng, L.C.

1980-01-01

In colliding beam storage rings the beam collision regions are generally so short that the beam-beam interaction can be considered as a series of evenly spaced non-linear kicks superimposed on otherwise stable linear oscillations. Most of the numerical studies on computers were carried out in just this manner. But for some reason this model has not been extensively employed in analytical studies. This is perhaps because all analytical work has so far been done by mathematicians pursuing general transcendental features of non-linear mechanics for whom this specific model of the specific system of colliding beams is too parochial and too repugnantly physical. Be that as it may, this model is of direct interest to accelerator physicists and is amenable to (1) further simplification, (2) physical approximation, and (3) solution by analogy to known phenomena

Stabilisation and precision pointing quadrupole magnets in the Compact Linear Collider (CLIC)

CERN Document Server

Janssens, Stef; Linde, Frank; van den Brand, Jo; Bertolini, Alessandro; Artoos, Kurt

This thesis describes the research done to provide stabilisation and precision positioning for the main beam quadrupole magnets of the Compact Linear Collider CLIC. The introduction describes why new particle accelerators are needed to further the knowledge of our universe and why they are linear. A proposed future accelerator is the Compact Linear Collider (CLIC) which consists of a novel two beam accelerator concept. Due to its linearity and subsequent single pass at the interaction point, this new accelerator requires a very small beam size at the interaction point, in order to increase collision effectiveness. One of the technological challenges, to obtain these small beam sizes at the interaction point, is to keep the quadrupole magnets aligned and stable to 1.5 nm integrated r.m.s. in vertical and 5 nm integrated root mean square (r.m.s.) in lateral direction. Additionally there is a proposal to create an intentional offset (max. 50 nm every 20 ms with a precision of +/- 1 nm), for several quadrupole ma...

Overview of new, upgraded, or proposed high energy physics facilities in the United States and Canada

International Nuclear Information System (INIS)

Gabriel, T.A.

1994-01-01

This article reviews six new, proposed, or upgraded accelerator facilities in the United States and Canada. All of the accelerators that are presented here in one form or fashion challenge the validity of the Standard Model of high energy physics which ''currently explains'' all experimentally know phenomena. These facilities include the Continuous Electron Beam Accelerator Facility (CEBAF) at Newport News, Virginia, the Kaon Factory at TRIUMF in Vancouver, British Columbia, Canada, the Asymmetric B Factory at the Stanford Linear Accelerator Center (SLAC) in Palo Alto, California, the Relativistic Heavy Ion Collider (RHIC) facility at Brookhaven National Laboratory in Upton, New York, the injector upgrade project at the Fermi National Accelerator Laboratory (FNAL) in Batavia, Illinois, and the Superconducting Super Collider Laboratory (SSCL) in Waxachachie, Texas

Seismic hazard studies for the high flux beam reactor at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Costantino, C.J.; Heymsfield, E.; Park, Y.J.; Hofmayer, C.H.

1991-01-01

This paper presents the results of a calculation to determine the site specific seismic hazard appropriate for the deep soil site at Brookhaven National Laboratory (BNL) which is to be used in the risk assessment studies being conducted for the High Flux Beam Reactor (HFBR). The calculations use as input the seismic hazard defined for the bedrock outcrop by a study conducted at Lawrence Livermore National Laboratory (LLNL). Variability in site soil properties were included in the calculations to obtain the seismic hazard at the ground surface and compare these results with those using the generic amplification factors from the LLNL study

Numerical Verification of the Power Transfer and Wakefield Coupling in the CLIC Two-Beam Accelerator

CERN Document Server

Candel, Arno; NG, C; Rawat, V; Schussman, G; Ko, K; Syratchev, I; Grudiev, A; Wuensch, W

2011-01-01

The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its two-beam accelerator (TBA) concept envisions complex 3D structures, which must be modeled to high accuracy so that simulation results can be directly used to prepare CAD drawings for machining. The required simulations include not only the fundamental mode properties of the accelerating structures but also the Power Extraction and Transfer Structure (PETS), as well as the coupling between the two systems. Time-domain simulations will be performed to understand pulse formation, wakefield damping, fundamental power transfer and wakefield coupling in these structures. Applying SLAC’s parallel finite element code suite, these large-scale problems will be solved on some of the largest supercomputers available. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel two-beam accelerator scheme.

RF power sources for 5--15 TeV linear colliders

International Nuclear Information System (INIS)

Wilson, P.B.

1996-09-01

After outlining the design of the NLC rf system at 1 TeV, the possibility of a leap in linear collider energy into the 5--15 TeV energy range is considered. To keep the active accelerator length and ac wall-plug power within reasonable bounds, higher accelerating gradients at higher rf frequencies will be necessary. Scaling relations are developed for basic rf system parameters as a function of frequency, and some specific parameter examples are given for colliders at 34 Ghz and 91 Ghz. Concepts for rf pulse compression system design and for high power microwave sources at 34 Ghz (for example sheet-beam and multiple-beam klystrons) are briefly discussed

Increased intensity performance of the Brookhaven AGS

International Nuclear Information System (INIS)

Raka, E.; Ahrens, L.; Frey, W.; Gill, E.; Glenn, J.W.; Sanders, R.; Weng, W.

1985-05-01

With the advent of H - injection into the Brookhaven AGS, circulating beams of up to 3 x 10 13 protons at 200 MeV have been obtained. Rf capture of 2.2 x 10 13 and acceleration of 1.73 x 10 13 up to the transition energy (approx. = 8 GeV) and 1.64 x 10 13 to full energy (approx. = 29 GeV) has been achieved. This represents a 50% increase over the best performance obtained with H + injection. The increase in circulation beam current is obtained without filling the horizontal aperture. This allows the rf capture process to utilize a larger longitudinal phase space area (approx. = 1 eV sec/bunch vs less than or equal to 0.6 eV sec with H + operation). The resulting reduction in relative longitudinal density partially offsets the increase in space charge effects at higher currents. In order to make the capture process independent of injected beam current, a dynamic beam loading compensation loop was installed on the AGS rf system. This is the only addition to the synchrotron itself that was required to reach the new intensity records. A discussion of injection, the rf capture process, and space charge effects is presented. 9 refs., 5 figs

The CERN SPS proton–antiproton collider

CERN Document Server

Schmidt, Rudiger

2016-01-01

One of CERN's most ambitious and successful projects was the search for the intermediate bosons, W and Z [1]. The accelerator part of the project relied on a number of innovations in accelerator physics and technology. The invention of the method of stochastic cooling and the extension by many orders of magnitude beyond the initial proof of principle demonstration allowed the construction of the Antiproton Accumulator. Major modifications to the 26 GeV PS complex and the conversion of the 300 GeV SPS, which had just started up as an accelerator, to a collider were required. The SPS collider had to master the beam–beam effect far beyond limits reached before and had to function in a tight symbiosis with the UA1 and UA2 experiments.

Transition radiation electron beam diagnostic study at ATF

International Nuclear Information System (INIS)

Qiu, X.Z.; Wang, X.J.; Batchelor, K.; Ben-Zvi, I.

1995-01-01

Recently we have started a program to develop transition radiation based electron beam diagnostics at the Accelerator Test Facility at Brookhaven National Laboratory. In this paper, we will discuss a technique to estimate the lower limit in electron beam divergence measurement with single foil transition radiation and two-foil transition radiation interferometer. Preliminary experimental data from 4.5 MeV electron beam will be presented

Transport and acceleration of low-emittance electron beams

International Nuclear Information System (INIS)

Henke, H.

1989-01-01

Linear accelerators for colliders and for free-electron lasers require beams with both high brightness and low emittance. Their transport and acceleration is limited by single-particle effects originating from injection jitter, from the unavoidable position jitter of components, and from chromaticity. Collective phenomena, essentially due to wake fields acting within the bunch, are most severe in the case of high-frequency structures, i.e. a small aperture. Whilst, in the past, the transverse wake-field effects were believed to be most serious, we know that they can even be beneficial when inducing a corresponding spread in betatron oscillation either by an energy spread along the bunch or by an RF focusing system acting on the bunch scale. This paper evaluates the different effects by simple analytical means after making use of the smooth focusing approximation and the two-particle model. Numerical simulation results are used for verification. 14 refs., 6 figs., 2 tabs

GPU-Powered Modelling of Nonlinear Effects due to Head-On Beam-Beam Interactions in High-Energy Hadron Colliders.

CERN Document Server

Furuseth, Sondre

2017-01-01

The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. This report discusses results from an implementation of the weak-strong model, studying the effects of head-on beam-beam interactions. The assumptions has been shown to be valid for configurations where the growth and losses of the beam are small. The tracking has been done using an original code which applies graphic cards to reduce the computation time. The bunches in the beams have been modelled cylindrically symmetrical, based on a Gaussian distribution in three dimensions. This choice fits well with bunches...

Brookhaven leak reactor to close

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