Temperature control feedback loops for the linac upgrade side coupled cavities at Fermilab

International Nuclear Information System (INIS)

Crisp, J.

1990-01-01

The linac upgrade project at Fermilab will replace the last 4 drift-tube linac tanks with seven side coupled cavity strings. This will increase the beam energy from 200 to 400 MeV at injection into the Booster accelerator. The main objective of the temperature loop is to control the resonant frequency of the cavity strings. A cavity string will constant of 4 sections connected with bridge couplers driven with a 12 MW klystron at 805 MHz. Each section is a side coupled cavity chain consisting of 16 accelerating cells and 15 side coupling cells. For the linac upgrade, 7 full cavity strings will be used. A separate temperature control system is planned for each of the 28 accelerating sections, the two transition sections, and the debuncher section. The cavity strings will be tuned to resonance for full power beam loaded conditions. A separate frequency loop is planned that will sample the phase difference between a monitor placed in the end cell of each section and the rf drive. The frequency loop will control the set point for the temperature loop which will be able to maintain the resonant frequency through periods within beam or rf power. The frequency loop will need the intelligence required to determine under what conditions the phase error information is valid and the temperature set point should be adjusted. This paper will discuss some of the reason for temperature control, the implementation, and some of the problems encountered. An appendix contains some useful constants and descriptions of some of the sensor and control elements used. 13 figs

Energy-Recovery Linacs for Commercial Radioisotope Production

International Nuclear Information System (INIS)

Johnson, Rolland Paul

2016-01-01

Most radioisotopes are produced by nuclear reactors or positive ion accelerators, which are expensive to construct and to operate. Photonuclear reactions using bremsstrahlung photon beams from less-expensive electron linacs can generate isotopes of critical interest, but much of the beam energy in a conventional electron linac is dumped at high energy, making unwanted radioactivation. The largest part of this radioactivation may be completely eliminated by applying energy recovery linac technology to the problem with an additional benefit that the energy cost to produce a given amount of isotope is reduced. Consequently, a Superconducting Radio Frequency (SRF) Energy Recovery Linac (ERL) is a path to a more diverse and reliable domestic supply of short-lived, high-value, high-demand isotopes at a cost lower than that of isotopes produced by reactors or positive-ion accelerators. A Jefferson Lab approach to this problem involves a thin photon production radiator, which allows the electron beam to recirculate through rf cavities so the beam energy can be recovered while the spent electrons are extracted and absorbed at a low enough energy to minimize unwanted radioactivation. The thicker isotope photoproduction target is not in the beam. MuPlus, with Jefferson Lab and Niowave, proposed to extend this ERL technology to the commercial world of radioisotope production. In Phase I we demonstrated that 1) the ERL advantage for producing radioisotopes is at high energies (~100 MeV), 2) the range of acceptable radiator thickness is narrow (too thin and there is no advantage relative to other methods and too thick means energy recovery is too difficult), 3) using optics techniques developed under an earlier STTR for collider low beta designs greatly improves the fraction of beam energy that can be recovered (patent pending), 4) many potentially useful radioisotopes can be made with this ERL technique that have never before been available in significant commercial quantities

Energy-Recovery Linacs for Commercial Radioisotope Production

Energy Technology Data Exchange (ETDEWEB)

Johnson, Rolland Paul [Muplus, Inc., Newport News, VA (United States)

2016-11-19

Most radioisotopes are produced by nuclear reactors or positive ion accelerators, which are expensive to construct and to operate. Photonuclear reactions using bremsstrahlung photon beams from less-expensive electron linacs can generate isotopes of critical interest, but much of the beam energy in a conventional electron linac is dumped at high energy, making unwanted radioactivation. The largest part of this radioactivation may be completely eliminated by applying energy recovery linac technology to the problem with an additional benefit that the energy cost to produce a given amount of isotope is reduced. Consequently, a Superconducting Radio Frequency (SRF) Energy Recovery Linac (ERL) is a path to a more diverse and reliable domestic supply of short-lived, high-value, high-demand isotopes at a cost lower than that of isotopes produced by reactors or positive-ion accelerators. A Jefferson Lab approach to this problem involves a thin photon production radiator, which allows the electron beam to recirculate through rf cavities so the beam energy can be recovered while the spent electrons are extracted and absorbed at a low enough energy to minimize unwanted radioactivation. The thicker isotope photoproduction target is not in the beam. MuPlus, with Jefferson Lab and Niowave, proposed to extend this ERL technology to the commercial world of radioisotope production. In Phase I we demonstrated that 1) the ERL advantage for producing radioisotopes is at high energies (~100 MeV), 2) the range of acceptable radiator thickness is narrow (too thin and there is no advantage relative to other methods and too thick means energy recovery is too difficult), 3) using optics techniques developed under an earlier STTR for collider low beta designs greatly improves the fraction of beam energy that can be recovered (patent pending), 4) many potentially useful radioisotopes can be made with this ERL technique that have never before been available in significant commercial quantities

Improved beam extraction for a negative hydrogen ion source for the LHC injector chain upgrade, Linac4

CERN Document Server

Midttun, Øystein; Scrivens, Richard

In the scope of an upgrade of the injector chain of CERN’s accelerator complex, a new linear accelerator, Linac4, is under construction. This accelerator will replace the existing 50 MeV proton linac, Linac2. By increasing the beam energy to 160 MeV, Linac4 makes it possible to double the brightness in the PSB, and ultimately increase the luminosity in the LHC. Linac4 will accelerate beams of negative hydrogen (H-) to be injected into the PSB by multi-turn, charge exchange injection. The ion source was initially based on the non-caesiated RF-volume source from DESY. However, the beam extraction from this source could not handle the 45 keV beam energy required by the RFQ. A new beam extraction system has therefore been designed, via IBSimu simulations [1], to extract and transport the H- ion beam respecting the Linac4 requirements. Key features of the extraction system is a tuneable puller voltage to adapt the extraction field to the ion and electron beam currents, and a magnetized Einzel lens to dump the co...

Superconducting RF for energy-recovery linacs

International Nuclear Information System (INIS)

Liepe, M.; Knobloch, J.

2006-01-01

Since superconducting RF for particle accelerators made its first appearance in the 1970s, it has found highly successful application in a variety of machines. Recent progress in this technology has made so-called Energy-Recovery Linacs (ERLs)-originally proposed in 1965-feasible, and interest in this type of machine has increased enormously. A superconducting linac is the driving heart of ERLs, and emittance preservation and cost efficiency is of utmost importance. The resulting challenges for the superconducting cavity technology and RF field control are manifold. In March 2005 the first international workshop on ERLs was held at Newport News, VA, to explore the potential of ERLs and to discuss machine-physics and technology challenges and their solutions. This paper reviews the state-of-the-art in superconducting RF and RF control for ERLs, and summarizes the discussions of the SRF working group on this technology during the ERL2005 workshop

Upgrading the Fermilab Linac local control system

International Nuclear Information System (INIS)

McCrory, E.S.; Goodwin, R.W.; Shea, M.F.

1991-02-01

A new control system for the Fermilab Linac is being designed, built and implemented. First, the nine-year-old linac control system is being replaced. Second, a control system for the new 805 MHz part of the linac is being built. The two systems are essentially identical, so that when the installations are complete, we will still have a single Linac Control System. 8 refs., 5 figs

Fermilab: Linac upgrade

International Nuclear Information System (INIS)

Anon.

1990-01-01

The Fermilab linear accelerator (Linac) was conceived 20 years ago, produced its first 200 MeV proton beam on 30 November 1970 and has run without major interruption ever since. Demands have steadily increased through the added complexity of the downstream chain of accelerators and by the increased patient load of the Neutron Therapy Facility

Electron linac for medical isotope production with improved energy efficiency and isotope recovery

Science.gov (United States)

Noonan, John; Walters, Dean; Virgo, Matt; Lewellen, John

2015-09-08

A method and isotope linac system are provided for producing radio-isotopes and for recovering isotopes. The isotope linac is an energy recovery linac (ERL) with an electron beam being transmitted through an isotope-producing target. The electron beam energy is recollected and re-injected into an accelerating structure. The ERL provides improved efficiency with reduced power requirements and provides improved thermal management of an isotope target and an electron-to-x-ray converter.

Upgrade plan for the control system of the KEK e-/e+ linac

International Nuclear Information System (INIS)

Furukawa, K.; Kamikubota, N.; Nakahara, K.; Abe, I.

1992-01-01

The KEK 2.5-GeV linac has been operating since 1982. However, in order to maintain reliable operation, the control system should be upgraded within a few years. We plan to replace the minicomputers and the main network connecting them. Thus, the architecture of the control software will also be revised. In the new system we should adopt software and hardware standards. In the next control system we will employ the TCP/IP (DARPA) protocol suite for the main network and Unix workstations to replace the minicomputers. For connections to the local controllers, VME bus (IEEE 1014) will be utilized. (author)

Design and construction of the main linac module for the superconducting energy recovery linac project at Cornell

Energy Technology Data Exchange (ETDEWEB)

Eichhorn, R.; Bullock, B.; He, Y.; Hoffstaetter, G.; Liepe, M.; O' Connell, T.; Quigley, P.; Sabol, D.; Sears, J.; Smith, E.; Veshcherevich, V. [Cornell Laboratory for Accelerator-based Science and Education (CLASSE), Cornell University, 161 Synchrotron Drive, Ithaca, NY 14853 (United States)

2014-01-29

Cornell University has been designing and building superconducting accelerators for various applications for more than 50 years. Currently, an energy-recovery linac (ERL) based synchrotron-light facility is proposed making use of the existing CESR facility. As part of the phase 1 R and D program funded by the NSF, critical challenges in the design were addressed, one of them being a full linac cryo-module. It houses 6 superconducting cavities- operated at 1.8 K in continuous wave (CW) mode - with individual HOM absorbers and one magnet/ BPM section. Pushing the limits, a high quality factor of the cavities (2⋅10{sup 10}) and high beam currents (100 mA accelerated plus 100 mA decelerated) are targeted. We will present the design of the main linac cryo-module (MLC) being finalized recently, its cryogenic features and report on the status of the fabrication which started in late 2012.

Electron linacs

Energy Technology Data Exchange (ETDEWEB)

Loew, G A; Schriber, S O [ed.

1976-11-01

A study was made of the present status of the thousand or so electron linacs in the world, and future trends in the field. These machines were classified according to their use: medical, industrial, and nuclear physics. In the medical category, two types of electron linacs are discussed: the conventional ones which are used for x-ray and electron therapy, and those which may in the future be used for negative pion therapy. Industrial machines discussed include linacs for radiographic and other specialized applications. In the nuclear physics category, the status of conventional low- and medium-energy as well as high duty cycle linacs is reviewed. The question of how one might obtain a c-w, 1 GeV, 100..mu..A electron linac is raised, and various options using recirculation and stretchers are examined. In this connection, the status of rf superconductivity is summarized. A review is given of linacs for injectors into synchrotrons and e/sup +-/ storage rings, and recent work done to upgrade the only multi-GeV linac, namely SLAC, is described.

Electron linacs

International Nuclear Information System (INIS)

Loew, G.A.

1976-01-01

To study the present status of the thousand or so electron linacs in the world, and future trends in the field, we have classified these machines according to their use: medical, industrial, and nuclear physics. In the medical category, two types of electron linacs are discussed: the conventional ones which are used for X-ray and electron therapy, and those which may in the future be used for negative pion therapy. The section on industrial machines includes linacs for radiographic and other specialized applications. In the nuclear physics category, the status of conventional low- and medium-energy as well as high duty cycle linacs is reviewed. The question of how one might obtain a C.W., 1 GeV, 100 μA electron linac is raised and various options using recirculation and stretchers are examined. In this connection, the status of RF superconductivity is summarized. Following, there is a review of linacs for injectors into synchrotrons and e +- storage rings. The paper ends with a description of recent work done to upgrade the only multi-GeV linac, namely SLAC. (author)

Recovery Act. Tapoco project. Cheoah upgrade

Energy Technology Data Exchange (ETDEWEB)

Tran, Paul [Alcoa Inc., Alcoa Center, PA (United States)

2013-10-02

Under Funding Opportunity Announcement Number: DE-FOA-0000120, Recovery Act: Hydroelectric Facility Modernization, Alcoa Power Generating Inc. (APGI), a fully owned subsidiary of Alcoa Inc., implemented major upgrades at its Cheoah hydroelectric facility near Robbinsville, North Carolina.

1-GeV Linac Upgrade Study at Fermilab

International Nuclear Information System (INIS)

Popovic, M.; Moretti, A.; Noble, R.; Schmidt, C.W.

1998-09-01

A linac injector for a new proton source complex at Fermilab is assumed to have a kinetic energy of 1 GeV. This linac would be sized to accelerate 100 mA of H - beam in a 200 microsecond pulse at a 15 Hz repetition rate. This would be adequate to produce ∼10 14 protons per pulse allowing for future improvements of the new proton source complex. An alternate proposal is to add 600 MeV of side coupled cavity linac at 805 MHz to the existing 400 MeV Linac. This addition may either be in a new location or use the present Booster tunnel. A discussion of these possibilities will be given

Status and performance of PF injector linac

International Nuclear Information System (INIS)

Sato, Isamu

1994-01-01

PF injector linac has been improved on a buncher section for accelerating of intense electron beam, and reinforced a focusing system of the positron generator linac for the expansion of phase space. In this presentation, I shall report present status and performance of PF injector linac, and discuss its upgrade program for B-factory project. (author)

Status and Future Plans of JAERI Eergy-Recovery Linac FEL

CERN Document Server

Hajima, R; Kikuzawa, N; Minehara, E J; Nagai, R; Nishimori, N; Nishitani, T; Sawamura, M; Yamauchi, T

2005-01-01

An energy-recovery linac for a high-power free-electron laser is in operation at Japan Atomic Energy Research Institute (JAERI). In this paper, we report results of research activities and future plans of JAERI ERL-FEL, which are the construction of FEL transport line, the operation of newly-installed RF controller and IOTs, the development of super-lattice photo cathode.

Linac4 Technical Design Report

CERN Document Server

Arnaudon, L; Baylac, M; Bellodi, G; Body, Y; Borburgh, J; Bourquin, P; Broere, J; Brunner, O; Bruno, L; Carli, C; Caspers, Friedhelm; Cousineau, S M; Cuvet, Y; De Almeida Martins, C; Dobers, T; Fowler, T; Garoby, R; Gerigk, F; Goddard, B; Hanke, K; Hori, M; Jones, M; Kahle, K; Kalbreier, Willi; Kroyer, T; Küchler, D; Lombardi, A M; López-Hernandez, L A; Magistris, M; Martini, M; Maury, S; Page, E; Paoluzzi, M; Pasini, M; Raich, U; Rossi, C; Royer, J P; Sargsyan, E; Serrano, J; Scrivens, R; Silari, M; Timmins, M; Venturini-Delsolaro, W; Vretenar, M; Wegner, R; Weterings, W; Zickler, T

2006-01-01

Linac4 is an H- linear accelerator, intended to replace Linac2 as injector to the PS Booster (PSB). By delivering to the PSB a beam at 160 MeV energy, Linac4 will provide the conditions to double the brightness and intensity of the beam from the PSB, thus removing the first bottleneck towards higher brightness for the LHC and simplifying operation. Moreover, this new linac constitutes an essential component of any of the envisaged LHC upgrade scenarios and could open the way to future extensions of the CERN accelerator complex towards higher performance. This Technical Design Report presents a detailed technical overview of the Linac4 design as it stands at end 2006.

Start-To-End Simulations of the Energy Recovery Linac Prototype FEL

CERN Document Server

Gerth, Christopher; Muratori, Bruno; Owen, Hywel; Thompson, Neil R

2004-01-01

Daresbury Laboratory is currently building an Energy Recovery Linac Prototype (ERLP) that serves as a testbed for the study of beam dynamics and accelerator technology important for the design and construction of the proposed 4th Generation Light Source (4GLS) project. Two major objectives for the ERLP are the operation of an oscillator infra-red FEL and demonstration of energy recovery from an electron bunch with an energy spread induced by the FEL. In this paper we present start-to-end simulations including the FEL of the ERLP. The beam dynamics in the high-brightness injector, which consists of a DC photocathode gun and a super-conducting booster, have been modelled using the particle tracking code ASTRA. After the main linac, in which the particles are accelerated to 35 MeV, particles have been tracked with the code ELEGANT. The 3D code GENESIS was used to model the FEL interaction with the electron beam. Different modes of operation and their impact on the design of the ERLP are discussed.

Update of the Linac4-PSB Transfer Line

CERN Document Server

HEIN, Lutz

2010-01-01

The installation of Linac4 represents the first step of the upgrade plans of the CERN accelerator complex for the future in order to raise the available proton flux to attain amongst others the LHC ultimate luminosity. This linac is capable to accelerate H--ions from 45keV to 160MeV, which will be injected into the Proton Synchrotron Booster (PSB). The increase of energy from 50MeV (Linac2) to 160MeV (Linac4) allows to overcome the space charge limitations at the PSB injection, which is the main bottleneck towards higher beam brightness in the downstream accelerator chain. In order to preserve beam quality from the outlet of Linac4 to PSB injection the design of the transfer line becomes crucial. As the location of Linac4 was chosen in view of upgrade scenarios, the construction of a new transfer line is foreseen, see ref.[1] and ref.[2]. Here part of the Linac2-PSB transfer line will be re-used. In the new part of the transfer line the beam is horizontally and vertically adjusted towards the bending magnet B...

Progress in design of the SNS linac

International Nuclear Information System (INIS)

Hardekopf, R.

2001-01-01

The Spallation Neutron Source (SNS) is a six-laboratory collaboration to build an intense pulsed neutron facility at Oak Ridge, TN. The linac design has evolved from the conceptual design presented in 1997 in order to achieve higher initial performance and to incorporate desirable upgrade features. The linac is now designed to produce 2-MW beam power using a combination of radio-frequency quadrupole (RFQ) linac, drift-tube linac (DTL), coupled-cavity linac (CCL), and superconducting-RF (SRF) linac. Designs of each of these elements support he high peak intensity and high quality beam required for injection into the SNS accumulator ring. This paper will trace the evolution of the linac design and the progress made in the R and D program. (author)

Two-pulse acceleration for BEPCII injector linac

International Nuclear Information System (INIS)

Pei Shilun; Wang Shuhong; Lu Weibin

2007-01-01

In order to double the injection rate of positron beam from the linac to the storage ring of BEPC II, a two-pulse generation and acceleration scheme has been proposed. The two-pulse simulation by programs including LIAR, PARMELA, EGUN and TRANSPORT is described first and the method is applied in the beam dynamics studies of BEPC II linac. The experiment of two-pulse acceleration was performed in BEPC II linac and some preliminary results are obtained, which provides a good reference for further upgrading of BEPC II injector linac. (authors)

High field electron linacs

International Nuclear Information System (INIS)

Le Duff, J.

1985-12-01

High field electron linacs are considered as potential candidates to provide very high energies beyond LEP. Since almost twenty years not much improvement has been made on linac technologies as they have been mostly kept at low and medium energies to be used as injectors for storage rings. Today, both their efficiency and their performances are being reconsidered, and for instance the pulse compression sheme developed at SLAC and introduced to upgrade the energy of that linac is a first step towards a new generation of linear accelerators. However this is not enough in terms of power consumption and more development is needed to improve both the efficiency of accelerating structures and the performances of RF power sources

Beam Line Design and Beam Physics Study of Energy Recovery Linac Free Electron Laser at Peking University

International Nuclear Information System (INIS)

Wang, Guimei

2011-01-01

Energy recovering linac (ERL) offers an attractive alternative for generating intense beams of charged particles by approaching the operational efficiency of a storage ring while maintaining the superior beam quality typical of a linear accelerator. In ERLs, the decelerated beam cancels the beam loading effects of the accelerated beam with high repetition rate. Therefore, ERLs can, in principle, accelerate very high average currents with only modest amounts of RF power. So the efficiency of RF power to beam is much higher. Furthermore, the energy of beam to dump is lower, so it will reduce dump radiation. With the successful experiments in large maximum-to-injection energy ratio up to 51:1 and high power FEL up to 14kW, the use of ERL, especially combining with superconducting RF technology, provides a potentially powerful new paradigm for generation of the charged particle beams used in MW FEL, synchrotron radiation sources, high-energy electron cooling devices and so on. The 3+1/2 DC-SC photo injector and two 9cell TESLA superconducting cavity for IR SASE FEL in PKU provides a good platform to achieve high average FEL with Energy Recovery. The work of this thesis is on Beam line design and Beam dynamics study of Energy Recovery Linac Free Electron Laser for Peking University. It is the upgrade of PKU facility, which is under construction. With ERL, this facility can work in CW mode, so it can operate high average beam current without RF power constraint in main linac and generate high average FEL power. Moreover, it provides a test facility to study the key technology in ERL. System parameters are optimized for PKU ERL-FEL. The oscillation FEL output power is studied with different bunch charge, transverse emittance, bunch length and energy spread. The theory of optimal RF power and Q ext with ERL and without ERL is analyzed and applied to PKU injector and linac including microphonic effect. pace charge effect in the injector and merger is studied for beam energy

Beam Line Design and Beam Physics Study of Energy Recovery Linac Free Electron Laser at Peking University

Energy Technology Data Exchange (ETDEWEB)

Wang, Guimei [Peking Univ., Beijing (China)

2011-12-31

Energy recovering linac (ERL) offers an attractive alternative for generating intense beams of charged particles by approaching the operational efficiency of a storage ring while maintaining the superior beam quality typical of a linear accelerator. In ERLs, the decelerated beam cancels the beam loading effects of the accelerated beam with high repetition rate. Therefore, ERLs can, in principle, accelerate very high average currents with only modest amounts of RF power. So the efficiency of RF power to beam is much higher. Furthermore, the energy of beam to dump is lower, so it will reduce dump radiation. With the successful experiments in large maximum-to-injection energy ratio up to 51:1 and high power FEL up to 14kW, the use of ERL, especially combining with superconducting RF technology, provides a potentially powerful new paradigm for generation of the charged particle beams used in MW FEL, synchrotron radiation sources, high-energy electron cooling devices and so on. The 3+1/2 DC-SC photo injector and two 9cell TESLA superconducting cavity for IR SASE FEL in PKU provides a good platform to achieve high average FEL with Energy Recovery. The work of this thesis is on Beam line design and Beam dynamics study of Energy Recovery Linac Free Electron Laser for Peking University. It is the upgrade of PKU facility, which is under construction. With ERL, this facility can work in CW mode, so it can operate high average beam current without RF power constraint in main linac and generate high average FEL power. Moreover, it provides a test facility to study the key technology in ERL. System parameters are optimized for PKU ERL-FEL. The oscillation FEL output power is studied with different bunch charge, transverse emittance, bunch length and energy spread. The theory of optimal RF power and Q{sub ext} with ERL and without ERL is analyzed and applied to PKU injector and linac including microphonic effect. pace charge effect in the injector and merger is studied for beam

Status of RF system for the JAERI energy-recovery linac FEL

International Nuclear Information System (INIS)

Sawamura, Masaru; Nagai, Ryoji

2006-01-01

The two types of the RF sources are used for the JAERI ERL-FEL. One is an all-solid state amplifier and the other is an inductive output tube (IOT). There are advantages of little failure and wide bandwidth for the all-solid state amplifier, low cost and high efficiency for IOT. The property of low cost with the IOT is suitable for a large machine like an energy recovery linac (ERL)

Thermionic RF Gun and Linac Pre-Injector for SPEAR3

Energy Technology Data Exchange (ETDEWEB)

Park, S.

2003-08-11

Preparations are underway to upgrade the Spear2 to the third generation light source. Installation of all the subsystems will start in April 2003. Although the Spear3 RF system is entirely different from the present form, the pre-injector gun/linac and booster synchrotron will remain the same even after the upgrade. The thermionic rf gun reliability and stability are to be improved to inject 500 mA of stored current in shortest possible time. When a top-up mode is enforced, where the stored beam decay is replenished to maintain the constant current and thus constant light intensity, the Spear3 will take injection every few minutes. In that case the gun, linac, and booster must stay on at all times. In this report we will describe some improvements made on the gun and linac in the recent past, as well as their present performance and future upgrade to be made.

CAS on Free-Electron Lasers and Energy Recovery Linacs in Hamburg

CERN Multimedia

CERN Accelerator School

2016-01-01

The CERN Accelerator School (CAS) and DESY held a jointly-organised specialised course on Free-Electron Lasers and Energy Recovery Linacs (FELs and ERLs) in Hamburg, Germany, from 31 May to 10 June 2016.      The course was held in the Hotel Scandic Emporio in Hamburg and was attended by 68 participants of 13 nationalities, coming from countries as far away as China, Iran and Japan. The intensive programme comprised 44 lectures and one seminar. Following introductory lectures on electromagnetism, relativity and synchrotron radiation issues, the basic requirements of linacs and ERLs were discussed. Detailed lectures on the theory of FEL science followed. Undulators and the process of lasing and seeding were covered in some detail along with lectures on various beam dynamics and beam control issues. Case studies, for which seven hours were allocated, completed the academic programme. For these, the students were divided into small groups and tasked with completing the basic desig...

ANU LINAC upgrade using multi-stub resonators

Indian Academy of Sciences (India)

LINAC development work at ANU is currently aimed at improving ... current through the rf joint at the base of the outer wall and so increasing joint losses. The ... The stub geometry was developed with a help of Superfish/Poisson software [8].

Linac design study for an intense neutron-source driver

International Nuclear Information System (INIS)

Lynch, M.T.; Browman, A.; DeHaven, R.; Jameson, R.; Jason, A.; Neuschaefer, G.; Tallerico, P.; Regan, A.

1993-01-01

The 1-MW spallation-neutron source under design study at Los Alamos is driven by a linac-compressor-ring scheme that utilizes a large portion of the existing Los Alamos Meson Physics Facility (LAMPF) linac, as well as the facility infrastructure. The project is referred to as the National Center for Neutron Research (NCNR). A second phase of the proposal will upgrade the driver power to 5 MW. A description of the 1-MW scheme is given in this paper. In addition, the upgrade path to the substantial increase of beam power required for the 5 MW scenario is discussed

CAS - CERN Accelerator School: Free Electron Lasers and Energy Recovery Linacs

CERN Document Server

2018-01-01

These proceedings collate lectures given at the course on Free Electron Lasers and Energy Recovery Linacs (FELsand ERLs), organised by the CERN Accelerator School (CAS). The course was held at the Hotel Scandic HamburgEmporio, Hamburg, Germany from 31 May to 10 June 2016, in collaboration with DESY. Following introductorylectures on radiation issues, the basic requirements on linear accelerators and ERLs are discussed. Undulators andthe process of seeding and lasing are then treated in some detail, followed by lectures on various beam dynamicsand controls issues.

Fast ferroelectric phase shifters for energy recovery linacs

Directory of Open Access Journals (Sweden)

S. Yu Kazakov

2010-11-01

Full Text Available Fast phase shifters are described that use a novel barium strontium titanate ceramic that can rapidly change its dielectric constant as an external bias voltage is changed. These phase shifters promise to reduce by ∼10 times the power requirements for the rf source needed to drive an energy recovery linac (ERL. Such phase shifters will be coupled with superconducting radiofrequency cavities so as to tune them to compensate for phase instabilities, whether beam-driven or those caused by microphonics. The most promising design is presented, which was successfully cold tested and demonstrated a switching speed of ∼30  ns for 77 deg, corresponding to <0.5  ns per deg of rf phase. Other crucial issues (losses, phase shift values, etc. are discussed.

Overview of the Pelletron Linac facility, Mumbai

International Nuclear Information System (INIS)

Pillay, R.G.

2011-01-01

The Pelletron LINAC Facility at TIFR, Mumbai, comprising the 14 MV Pelletron and the superconducting LINAC booster caters to a variety of experiments in basic and applied Sciences. The Liquid Helium Refrigeration plant for the LINAC has been upgraded to enhance the refrigeration capacity. New instrumentation and interface for control and monitor of the cryogenic parameters, beam diagnostics and beam transport devices have been developed and installed. Digital implementation of the LLRF control has been demonstrated. All seven beam lines in new user halls have been commissioned and several new experimental setups have been added. (author)

All Digital IQ Servo-System for CERN Linacs

CERN Document Server

Rohlev, A; Garoby, R

2003-01-01

A new VME based system has been developed and built at CERN for the servo loops regulating the field in the linac accelerating structure. It makes use of high speed digital In-phase/Quadrature (IQ) detection, digital processing, and digital IQ modulation. The digital processing and IQ modulation is done in a single PLD. The system incorporates continually variable set points, iterative learning, feed forward as well as extensive diagnostics and other features well suited for digital implementations. Built on a single VME card, it will be first used in the energy ramping RF chain of the CERN Heavy Ion Linac (linac 3) and later for upgrading the present proton linac (linac 2). This system serves also as a prototype for the future Superconducting Proton Linac (SPL). The design principle and the experimental results are described.

Evolution of the 400 MeV linac design

International Nuclear Information System (INIS)

MacLachlan, J.A.

1987-01-01

The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also

Evolution of the 400 MeV linac design

Energy Technology Data Exchange (ETDEWEB)

MacLachlan, J.A.

1987-11-09

The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also.

A linac for the Spallation Neutron Source

International Nuclear Information System (INIS)

Jason, A.J.

1998-01-01

The Spallation Neutron Source Project (SNS), to be constructed at Oak Ridge National Laboratory, accelerates H - ions to an energy of 1.0 GeV with an average current of 1-mA for injection into an accumulator ring that produces the short intense burst of protons needed for the spallation-neutron source. The linac will be the most intense source of H - ions and as such requires advanced design techniques to meet project technical goals. In particular, low beam loss is stressed for the chopped beam placing strong requirements on the beam dynamics and linac construction. Additionally, the linac is to be upgraded to the 2- and 4-MW beam-power levels with no increase in duty factor. The author gives an overview of the linac design parameters and design choices made

History of the JAERI linac facility for 33 years

International Nuclear Information System (INIS)

Ohkubo, Makio; Mizumoto, Motoharu; Nakajima, Yutaka; Mashiko, Katsuo

1994-01-01

The JAERI electron linear accelerator will be shutdown and disassembled at the end of 1993. At the JAERI, a prototype 20 MeV linac was constructed at 1960, and was used for the neutron time-of-flight experiments and for the isotope productions. An upgraded 120 MeV linac was constructed at 1972, and was used for many fields of research works until 1993. History of the JAERI Linac and the results of the works made using these facilities are reviewed, and also R/D on the accelerator engineering are described briefly. (author)

Vacuum system of the compact Energy Recovery Linac

Energy Technology Data Exchange (ETDEWEB)

Honda, T., E-mail: tohru.honda@kek.jp; Tanimoto, Y.; Nogami, T.; Takai, R.; Obina, T.; Asaoka, S.; Uchiyama, T.; Nakamura, N. [High Energy Accelerator Research Organization (KEK) (1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan) (Japan)

2016-07-27

The compact Energy Recovery Linac (cERL), a test accelerator to establish important technologies demanded for future ERL-based light sources, was constructed in late 2013 at KEK. The accelerator was successfully commissioned in early 2014, and demonstrated beam circulation with energy recovery. In the cERL vacuum system, low-impedance vacuum components are required to circulate high-intensity, low-emittance and short-bunch electron beams. We therefore developed ultra-high-vacuum (UHV)-compatible flanges that can connect beam tubes seamlessly, and employed retractable beam monitors, namely, a movable Faraday cup and screen monitors. In most parts of the accelerator, pressures below 1×10{sup −7} Pa are required to mitigate beam-gas interactions. Particularly, near the photocathode electron gun and the superconducting (SC) cavities, pressures below 1×10{sup −8} Pa are required. The beam tubes in the sections adjoining the SC cavities were coated with non-evaporable getter (NEG) materials, to reduce gas condensation on the cryo-surfaces. During the accelerator commissioning, stray magnetic fields from the permanent magnets of some cold cathode gauges (CCGs) were identified as a source of the disturbance to the beam orbit. Magnetic shielding was specially designed as a remedy for this issue.

NSLS control system upgrade

International Nuclear Information System (INIS)

Smith, J.D.; Ramamoorthy, Susila; Tang, Y.N.

1994-01-01

The NSLS consists of two storage rings, a booster and a linac. A major upgrade of the control system (installed in 1978) was undertaken and has been completed. The computer architecture is being changed from a three level star-network to a two level distributed system. The microprocessor subsystem, host computer and workstations, communication link and the main software components are being upgraded or replaced. Since the NSLS rings operate twenty four hours a day a year with minimum maintenance time, the key requirement during the upgrade phase is a non-disruptive transition with minimum downtime. Concurrent with the upgrade, some immediate improvements were required. This paper describes the various components of the upgraded system and outlines the future plans. ((orig.))

NSLS control system upgrade

International Nuclear Information System (INIS)

Smith, J.D.; Ramamoorthy, S.; Tang, Yong N.

1995-01-01

The NSLS consists of two storage rings, a booster and a linac. A major upgrade of the control system (installed in 1978) was undertaken and has been completed. The computer architecture is being changed from a three level star-network to a two level distributed system. The microprocessor subsystem, host computer and workstations, communication link and the main software components are being upgraded or replaced. Since the NSLS rings operate twenty four hours a day a year with minimum maintenance time, the key requirement during the upgrade phase is a non-disruptive transition with minimum downtime. Concurrent with the upgrade, some immediate improvements were required. This paper describes the various components of the upgraded system and outlines the future plans

Discussion of superconducting and room-temperature high-intensity ion linacs

International Nuclear Information System (INIS)

Jameson, R.A.

1996-01-01

The point of view taken in this discussion is that the basic technology base exists in all essential respects for both superconducting or room-temperature rf linac accelerators and associated power and control systems, and thus a project can make a choice between these technologies on overall system considerations. These include performance, cost, availability, flexibility, and upgradability. Large high-intensity neutron source proposals involving light-ion rf linacs in three categories are reviewed in this context. The categories arc cw linacs to high (∼1 GeV) and low (∼40 MeV) output energy, and pulsed linacs to energy ∼1 GeV

4-rod RFQ linac for ion implantation

Energy Technology Data Exchange (ETDEWEB)

Fujisawa, Hiroshi; Hamamoto, Nariaki; Inouchi, Yutaka [Nisshin Electric Co. Ltd., Kyoto (Japan)

1997-03-01

A 34 MHz 4-rod RFQ linac system has been upgraded in both its rf power efficiency and beam intensity. The linac is able to accelerate in cw operation 0.83 mA of a B{sup +} ion beam from 0.03 to 0.91 MeV with transmission of 61 %. The rf power fed to the RFQ is 29 kW. The unloaded Q-value of the RFQ has been improved approximately 61 % to 5400 by copper-plating stainless steel cooling pipes in the RFQ cavity. (author)

Development of an Eddy Current Septum for LINAC4

CERN Document Server

Barnes, M; Borburgh, J; Fowler, T; Goddard, B; Ueda, A; Weterings, W

2008-01-01

A linear accelerator (linac) is the first stage of the CERN accelerator complex. The linac defines the beam quality for subsequent stages of acceleration and the reliability has to be high as a fault of the linac shuts down all other machines. The existing linacs at CERN were designed 30 or more years ago: recent upgrades allowed the linacs to reach LHC requirements but also showed that they are at the limit of their brightness and intensity capabilities. A replacement Superconducting Proton Linac (SPL) has been proposed; the initial part of the SPL is termed LINAC4. The LINAC4 injection bump would be made up of a set of four pulsed dipole magnets; the first of these magnets (BS1) must act as a septum with a thin element dividing the high-field region of the circulating beam from the field-free region through which injected $H^{-}$ beam must pass. The initial specifications for BS1 required; a deflection of 66 mrad at 160 MeV, achieved with a peak field of 628 mT and a length of 250 mm: the field fall time wa...

High duty factor Plasma Generator for CERN’s Superconducting Proton Linac

CERN Document Server

Lettry, J; Scrivens, R; Chaudet, E; Faircloth, D; Favre, G; Geisser, JM; Kuchler, D; Mathot, S; Midttun, O; Paoluzzi, M; Schmitzer, C; Steyaert, D

2010-01-01

CERN’s Linac4 is a 160 MeV linear accelerator currently under construction. It will inject negatively charged hydrogen ions into CERN’s PS-Booster. Its ion source is a non-cesiated RF driven H- volume source directly inspired from the one of DESY and is aimed to deliver pulses of 80 mA of H- during 0.4 ms at a 2 Hz repetition rate. The Superconducting Proton Linac (SPL) project is part of the luminosity upgrade of the LHC, it consists of an extension of Linac4 up to 5 GeV and is foreseen to deliver protons to a future 50 GeV Synchrotron (PS2). For the SPL high power option (HP-SPL), the ion source would deliver pulses of 80 mA of H- during 1.2 ms and operate at a 50 Hz repetition rate. This significant upgrade motivates the design of the new water cooled plasma generator presented in this paper. Its engineering is based on the results of a finite element thermal study of the Linac4 H- plasma generator that identified critical components and thermal barriers. A cooling system is proposed which achieves the...

Observation of high-power coherent synchrotron radiation in the THz region from the JAEA energy recovery linac

International Nuclear Information System (INIS)

Takahashi, Toshiharu; Okuda, Shuichi; Minehara, Eisuke J.; Hajima, Ryoichi; Sawamura, Masaru; Nagai, Ryoji; Kikuzawa, Nobihiro; Iijima, Hokuto; Nishitani, Tomohiro; Nishimori, Nobuyuki

2007-01-01

The energy recovery linac (ERL) is able to generate high-power coherent synchrotron radiation (CSR) in the terahertz and the millimeter-wave regions, because it produces shorter bunches than usual storage rings and a higher current than conventional linacs. The spectrum of CSR has been measured at the JAEA-ERL in the wavenumber range from 0.5 to 15 cm -1 . The detected power was 2x10 -4 W/cm -1 at 2.5 cm -1 for the average beam current of 17.7 μA. When the infrared FEL was operated with the undulator in the ERL, the CSR spectrum was shifted to the longer wavelengths because of the energy broadening of the electron beam. (author)

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.

A hot-spare injector for the APS linac

International Nuclear Information System (INIS)

Lewellen, J. W.

1999-01-01

Last year a second-generation SSRL-type thermionic cathode rf gun was installed in the Advanced Photon Source (APS) linac. This gun (referred to as ''gun2'') has been successfully commissioned and now serves as the main injector for the APS linac, essentially replacing the Koontz-type DC gun. To help ensure injector availability, particularly with the advent of top-up mode operation at the APS, a second thermionic-cathode rf gun will be installed in the APS linac to act as a hot-spare beam source. The hot-spare installation includes several unique design features, including a deep-orbit Panofsky-style alpha magnet. Details of the hot-spare beamline design and projected performance are presented, along with some plans for future performance upgrades

The Atlas upgrade project

International Nuclear Information System (INIS)

Bollinger, L.M.

1988-01-01

ATLAS is a heavy-ion accelerator system consisting of a 9-MV tandem electrostatic injector coupled to a superconducting linac. A project now well advanced will upgrade the capabilities of ATLAS immensely by replacing the tandem and its negative-ion source with a positive-ion injector that consists of an electron-cyclotron resonance (ECR) ion source and a 12-MV superconducting injector linac of novel design. This project will increase the beam intensity 100 fold and will extend the projectile-mass range up to uranium. Phase 1 of the work, which is nearing completion in late 1988, will provide an injector comprising the ECR source and its 350-kV voltage platform, beam analysis and bunching systems, beam lines, and a prototype 3-MV linac. The ECR source and its voltage platform are operational, development of the new class of low-frequency interdigital superconducting resonators required for the injector linac has been completed, and assembly of the whole system is in progress. Test runs and then routine use of the Phase 1 injector systems are planned for early 1989, and the final 12-MV injector linac will be commissioned in 1990. 12 refs., 6 figs

Beam Diagnostics for the BNL Energy Recovery Linac Test Facility

International Nuclear Information System (INIS)

Cameron, Peter; Ben-Zvi, Ilan; Blaskiewicz, Michael; Brennan, Michael; Connolly, Roger; Dawson, William; Degen, Chris; DellaPenna, Al; Gassner, David; Kesselman, Martin; Kewish, Jorg; Litvinenko, Vladimir; Mead, Joseph; Oerter, Brian; Russo, Tom; Vetter, Kurt; Yakimenko, Vitaly

2004-01-01

An Energy Recovery Linac (ERL) test facility is presently under construction at BNL. The goals of this test facility are first to demonstrate stable intense CW electron beam with parameters typical for the RHIC e-cooling project (and potentially for eRHIC), second to test novel elements of the ERL (high current CW photo-cathode, superconducting RF cavity with HOM dampers, and feedback systems), and finally to test lattice dependence of stability criteria. Planned diagnostics include position monitors, loss monitors, transverse profile monitors (both optical and wires), scrapers/halo monitors, a high resolution differential current monitor, phase monitors, an energy spread monitor, and a fast transverse monitor (for beam break-up studies and the energy feedback system). We discuss diagnostics challenges that are unique to this project, and present preliminary system specifications. In addition, we include a brief discussion of the timing system

Linac4: injecting new life into the LHC

CERN Multimedia

Antonella Del Rosso

2015-01-01

Construction work is nearing completion on the ion source for Linac4, the new linear accelerator that forms part of the LHC injector upgrade programme. Here we find out more about this essential component of the accelerator chain, designed and built at CERN.     The image shows the Linac4 H- source. The red light is the alpha line of the visible hydrogen emission spectrum. The ion source is a key component of Linac4, the linear accelerator that from 2018 will supply H- ions (hydrogen atoms with an extra electron) at 160 MeV for injection into the accelerator complex. As the only ion source at CERN, Linac4 must be highly reliable, which requires a full understanding of the production mechanisms, the simulation of physical processes and the validation of those processes through experimentation. “This source is the result of much fruitful collaboration,” says Jacques Lettry of the BE department. “Its design was inspired by the many sources of th...

Comparative assessment of alternative cycles for waste heat recovery and upgrade

International Nuclear Information System (INIS)

Little, Adrienne B.; Garimella, Srinivas

2011-01-01

Thermally activated systems based on sorption cycles, as well as mechanical systems based on vapor compression/expansion are assessed in this study for waste heat recovery applications. In particular, ammonia-water sorption cycles for cooling and mechanical work recovery, a heat transformer using lithium bromide-water as the working fluid pair to yield high temperature heat, and organic Rankine cycles using refrigerant R245fa for work recovery as well as versions directly coupled to a vapor compression cycle to yield cooling are analyzed with overall heat transfer conductances for heat exchangers that use similar approach temperature differences for each cycle. Two representative cases are considered, one for smaller-scale and lower temperature applications using waste heat at 60 o C, and the other for larger-scale and higher temperature waste heat at 120 o C. Comparative assessments of these cycles on the basis of efficiencies and system footprints guide the selection of waste heat recovery and upgrade systems for different applications and waste heat availabilities. Furthermore, these considerations are used to investigate four case studies for waste heat recovery for data centers, vehicles, and process plants, illustrating the utility and limitations of such solutions. The increased implementation of such waste heat recovery systems in a variety of applications will lead to decreased primary source inputs and sustainable energy utilization. -- Highlights: → Sorption and mechanical pathways for the conversion of waste heat streams to work, cooling, and temperature boosting were investigated. → Waste heat sources including 300 W of energy at 60 o C and 1 kW of energy at 120 o C were analyzed. → Up to about seventy percent of the input waste heat can be converted to cooling. → Up to about ten percent can be converted to work. → Up to about 47 percent can be upgraded to a higher temperature.

Argonne's atlas control system upgrade

International Nuclear Information System (INIS)

Munson, F.; Quock, D.; Chapin, B.; Figueroa, J.

1999-01-01

The ATLAS facility (Argonne Tandem-Linac Accelerator System) is located at the Argonne National Laboratory. The facility is a tool used in nuclear and atomic physics research, which focuses primarily on heavy-ion physics. The accelerator as well as its control system are evolutionary in nature, and consequently, continue to advance. In 1998 the most recent project to upgrade the ATLAS control system was completed. This paper briefly reviews the upgrade, and summarizes the configuration and features of the resulting control system

LINAC4 low energy beam measurements

CERN Document Server

Hein, L M; Lallement, J B; Lombardi, A M; Midttun, O; Posocco, P; Scrivens, R

2012-01-01

Linac4 is a 160 MeV normal-conducting linear accelerator for negative Hydrogen ions (H−), which will replace the 50 MeV proton Linac (Linac2) as linear injector for the CERN accelerators. The low energy part, comprising a 45 keV Low Energy Beam Transport system (LEBT), a 3 MeV Radiofrequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) is being assembled in a dedicated test stand for pre-commissioning with a proton beam. During 2011 extensive measurements were done after the source and after the LEBT with the aim of preparing the RFQ commissioning and validating the simulation tools, indispensable for future source upgrades. The measurements have been thoroughly simulated with a multi-particle code, including 2D magnetic field maps, error studies, steering studies and the generation of beam distribution from measurements. Emittance, acceptance and transmission measurements will be presented and compared to the results of the simulations.

CERN Linac4 - The Space Charge Challenge Design and Commission

CERN Document Server

Hein, Lutz Matthias; Holzer, Bernhard

In the first phase of the upgrade program of the CERN accelerator complex the proton injector Linac2 will be replaced by a new, normal-conducting $H^-$ ion Linac, Linac4, allowing a significant increase of the proton flux intensity along the downstream accelerator complex. In the design of Linac4 three beam transport sections are implemented to match the beam between the different accelerator elements and to model the longitudinal pulse structure. These three beam transport sections, which are the most critical locations in terms of beam quality preservation, are in the focus of this thesis. During the work of this thesis the low energy beam transport (LEBT), which is required to match the source beam to the radiofrequency quadrupole (RFQ), has been commissioned and its beam dynamics re-constructed. The measurement campaign used to re-construct the LEBT beam dynamics was performed with the aim to prepare the RFQ commissioning and to maximise the LEBT performance. Downstream of the Linac4 accelerator the beam...

Operational parameters of a 2.0-MeV RFQ linac

International Nuclear Information System (INIS)

Sander, O.R.; Purser, F.O.; Rusthoi, D.P.

1984-01-01

After extensive upgrading, our radio-frequency quadrupole (RFQ) linac is again installed on the accelerator test stand (ATS). The measured parameters of the RFQ, such as the output transverse emittance, transmitted beam, average energy, and energy spread is presented

Status of the Upgrade of the CERN PS Booster

CERN Document Server

Hanke, K; Angoletta, M; Bartmann, W; Bartolome, S; Benedetto, E; Bertone, C; Blas, A; Bonnal, P; Borburgh, J; Bozzini, D; Butterworth, A; Carli, C; Carlier, E; Cole, J; Dahlen, P; Delonca, M; Dobers, T; Findlay, A; Froeschl, R; Hansen, J; Hay, D; Jensen, S; Lacroix, J; Le Roux, P; Lopez Hernandez, L; Maglioni, C; Masi, A; Mason, G; Mathot, S; Mikulec, B; Muttoni, Y; Newborough, A; Nisbet, D; Olek, S; Paoluzzi, M; Perillo-Marcone, A; Pittet, S; Puccio, B; Raginel, V; Riffaud, B; Ruehl, I; Sarrió Martínez, A; Tan, J; Todd, B; Venturi, V; Weterings, W

2013-01-01

The CERN PS Booster (PSB) is presently undergoing an ambitious consolidation and upgrade program within the frame of the LHC Injectors Upgrade (LIU) project. This program comprises a new injection scheme for H- ions from CERN’s new Linac4, the replacement of the main RF systems and an energy upgrade of the PSB rings from 1.4 to 2 GeV which includes the replacement of the main magnet power supply as well as the upgrade of the extraction equipment. This paper describes the status and plans of this work program.

Experimental study of simultaneous Athabasca bitumen recovery and upgrading using ultradispersed catalysts injection

Energy Technology Data Exchange (ETDEWEB)

Hashemi, R.; Pereira, P. [University of Calgary (Canada)

2011-07-01

As the demand for oil is continuously increasing, the need for unconventional resources is rising. Oil extraction from bitumen and heavy oil reservoirs requires advanced techniques in order to decrease the viscosity of the oil. To increase the recovered original oil in place (OOIP) of a reservoir and decrease refining costs, new techniques to upgrade oil in situ are being developed. The current study investigates the use of ultra-dispersed (UD) submicronic catalysts to decrease oil viscosity. The experiment involved the injection of the catalyst and hydrogen gas in a sand pack saturated with Athabasca bitumen. Analysis was carried out by building recovery curves, and by comparing the oil recovery from the catalyzed process with that of catalyst-free processes. The study demonstrated that the oil recovered from the new technique had higher API gravity and lower viscosity, indicating the success of the in situ upgrading process.

Release the beams! - Linac4 ready to hit the 50 MeV mark

CERN Multimedia

Katarina Anthony

2015-01-01

The Linac4 accelerator is now prepared to reach 50 MeV. This milestone energy - expected in the coming weeks - will allow the machine to act as a replacement for the ageing Linac2, four years before it takes over at the head of the accelerator chain in 2020.    Inside the Linac4 tunnel, the final DTL cavities will guide beams to 50 MeV.  (Image: Stephan Russenschuck.) The Linac4 accelerator will bring H- ion beams (hydrogen atoms with an extra electron) up to 160 MeV for injection into the PS Booster. As a key part of the LHC injector upgrade programme, Linac4 will allow the PS Booster to double its beam brightness, which will contribute to increasing the LHC’s luminosity. Linac4 will soon bring beams up to 50 MeV - the current energy delivered by the Linac2 accelerator. This milestone follows on from another recent accomplishment: the installation and commissioning of the final Drift Tube Linac (DTL) tank. Using an innovati...

Finite element thermal study of the Linac4 plasma generator

International Nuclear Information System (INIS)

Faircloth, D.; Kronberger, M.; Kuechler, D.; Lettry, J.; Scrivens, R.

2010-01-01

The temperature distribution and heat flow at equilibrium of the plasma generator of the rf-powered noncesiated Linac4 H - ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW rf power, 2 Hz repetition rate, and 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of the Superconducting Proton Linac (SPL), an extrapolation of the heat load toward 100 kW rf power, 50 Hz repetition rate, and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in the high-power mode of SPL.

Finite element thermal study of the Linac4 plasma generator

Energy Technology Data Exchange (ETDEWEB)

Faircloth, D. [STFC, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom); Kronberger, M.; Kuechler, D.; Lettry, J.; Scrivens, R. [BE-ABP, Hadron Sources and Linacs, CERN, CH-1211 Geneva (Switzerland)

2010-02-15

The temperature distribution and heat flow at equilibrium of the plasma generator of the rf-powered noncesiated Linac4 H{sup -} ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW rf power, 2 Hz repetition rate, and 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of the Superconducting Proton Linac (SPL), an extrapolation of the heat load toward 100 kW rf power, 50 Hz repetition rate, and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in the high-power mode of SPL.

The FFAG return loop for the CBETA Energy Recovery Linac

Energy Technology Data Exchange (ETDEWEB)

Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2017-04-28

The CBETA energy recovery linac uses a single xed eld alternating gradient (FFAG) beam line to return the beam for electron beams with four energies, ranging from 42 MeV to 150 MeV. To keep the beam line compact, the ends of the return line have a small radius of curvature, but the central part of the return line is straight. These are connected by transition lines that adiabatically change from one to the other. We rst describe the design or the arc cell. We then describe how a straight cell is created to be a good match to this arc cell. We then describe the design of the transition line between them. The design process makes use of eld maps for the desired magnets. Because we switch magnet types as we move from the arc, through the transition, and into the straight, there are discrete jumps in the elds that degrade the adiabaticity of the transition, and we describe corrections to manage that.

Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN.

Science.gov (United States)

Toivanen, V; Bellodi, G; Dimov, V; Küchler, D; Lombardi, A M; Maintrot, M

2016-02-01

Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT) section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented.

Mechanical Engineering of the Linac for the Spallation Neutron Source

International Nuclear Information System (INIS)

Bultman, N.K.; Chen, Z.; Collier, M.; Erickson, J.L.; Guthrie, A.; Hunter, W.T.; Ilg, T.; Meyer, R.K.; Snodgrass, N.L.

1999-01-01

The linac for the Spallation Neutron Source (SNS) Project will accelerate an average current of 1 mA of H - ions from 20 MeV to 1GeV for injection into an accumulator ring. The linac will be an intense source of H - ions and as such requires advanced design techniques to meet project technical goals as well as to minimize costs. The DTL, CCDTL and CCL are 466m long and operate at 805 MHz with a maximum H - input current of 28 mA and 7% rf duty factor. The Drift Tube Linac is a copper-plated steel structure using permanent magnetic quadrupoles. The Coupled-Cavity portions are brazed copper structures and use electromagnetic quads. RF losses in the copper are 80 MW, with total rf power supplied by 52 klystrons. Additionally, the linac is to be upgraded to the 2- and 4-MW beam power levels with no increase in duty factor. The authors give an overview of the linac mechanical engineering effort and discuss the special challenges and status of the effort

Conceptual Design for the New RPI 2020 Linac

Energy Technology Data Exchange (ETDEWEB)

Adolphsen, C.; Bane, K.; Dolgashev, V.; Jensen, A.; Haase, A.; Jongewaard, E.; Kemp, M.; Krasnykh, A.; Lewandowski, J.; Li, Z.; Neilson, J.; Pearson, C.; Tantawi, S.; Wang, J.; Yeremian, A.D.; /SLAC; Brand, P.; Danon, Y.; /Rensselaer Polytech. Inst.; Epping, B.; Donovan, T.; Block, R.; Leinweber, G.; /Knolls Atomic Power Lab.

2014-10-29

The Rensselaer Polytechnic Institute (RPI) spectrometer is an installation based on an L-band linear accelerator designed and installed many decades ago. While this installation has served many important experiments over the decades, a new more powerful and more flexible linac to serve a wider range of experiments is envisioned as an upgrade to the existing installation by 2020.

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

The ATLAS multi-user upgrade and potential applications

Energy Technology Data Exchange (ETDEWEB)

Mustapha, B.; Nolen, J. A.; Savard, G.; Ostroumov, P. N.

2017-12-01

With the recent integration of the CARIBU-EBIS charge breeder into the ATLAS accelerator system to provide for more pure and efficient charge breeding of radioactive beams, a multi-user upgrade of the ATLAS facility is being proposed to serve multiple users simultaneously. ATLAS was the first superconducting ion linac in the world and is the US DOE low-energy Nuclear Physics National User Facility. The proposed upgrade will take advantage of the continuous-wave nature of ATLAS and the pulsed nature of the EBIS charge breeder in order to simultaneously accelerate two beams with very close mass-to-charge ratios; one stable from the existing ECR ion source and one radioactive from the newly commissioned EBIS charge breeder. In addition to enhancing the nuclear physics program, beam extraction at different points along the linac will open up the opportunity for other potential applications; for instance, material irradiation studies at ~ 1 MeV/u and isotope production at ~ 6 MeV/u or at the full ATLAS energy of ~ 15 MeV/u. The concept and proposed implementation of the ATLAS multi-user upgrade will be presented. Future plans to enhance the flexibility of this upgrade will also be presented.

ARIEL e-LINAC: Commissioning and Development

Science.gov (United States)

Laxdal, R. E.; Zvyagintsev, V.

2016-09-01

A superconducting electron Linac (e-Linac) will be a part of the ARIEL facility for the production of radioactive ion beams (RIB) at TRIUMF. The e-Linac will consist of five 1.3GHz 9-cell cavities in three cryomodules delivering a 50MeV 10mA beam. The baseline operation will be single pass but a re-circulating ring is planned to allow either energy boost or energy recovery operation. The first stage of the accelerator which consists of two cryomodules has been successfully commissioned in 2014. The paper will discuss the superconducting radio-frequency (SRF) challenges of the accelerator. Cavities, crymodules and RF system design, preparation, and performance will be presented.

ARIEL e-LINAC: Commissioning and Development

International Nuclear Information System (INIS)

Laxdal, R.E.; Zvyagintsev, V.

2016-01-01

A superconducting electron Linac (e-Linac) will be a part of the ARIEL facility for the production of radioactive ion beams (RIB) at TRIUMF. The e-Linac will consist of five 1.3GHz 9-cell cavities in three cryomodules delivering a 50MeV 10mA beam. The baseline operation will be single pass but a re-circulating ring is planned to allow either energy boost or energy recovery operation. The first stage of the accelerator which consists of two cryomodules has been successfully commissioned in 2014. The paper will discuss the superconducting radio-frequency (SRF) challenges of the accelerator. Cavities, crymodules and RF system design, preparation, and performance will be presented. (paper)

Demonstration of low emittance in the Cornell energy recovery linac injector prototype

Directory of Open Access Journals (Sweden)

Colwyn Gulliford

2013-07-01

Full Text Available We present a detailed study of the six-dimensional phase space of the electron beam produced by the Cornell Energy Recovery Linac Photoinjector, a high-brightness, high repetition rate (1.3 GHz DC photoemission source designed to drive a hard x-ray energy recovery linac (ERL. A complete simulation model of the injector has been constructed, verified by measurement, and optimized. Both the horizontal and vertical 2D transverse phase spaces, as well as the time-resolved (sliced horizontal phase space, were simulated and directly measured at the end of the injector for 19 and 77 pC bunches at roughly 8 MeV. These bunch charges were chosen because they correspond to 25 and 100 mA average current if operating at the full 1.3 GHz repetition rate. The resulting 90% normalized transverse emittances for 19   (77  pC/bunch were 0.23±0.02 (0.51±0.04  μm in the horizontal plane, and 0.14±0.01 (0.29±0.02  μm in the vertical plane, respectively. These emittances were measured with a corresponding bunch length of 2.1±0.1 (3.0±0.2  ps, respectively. In each case the rms momentum spread was determined to be on the order of 10^{-3}. Excellent overall agreement between measurement and simulation has been demonstrated. Using the emittances and bunch length measured at 19  pC/bunch, we estimate the electron beam quality in a 1.3 GHz, 5 GeV hard x-ray ERL to be at least a factor of 20 times better than that of existing storage rings when the rms energy spread of each device is considered. These results represent a milestone for the field of high-brightness, high-current photoinjectors.

Delta undulator for Cornell energy recovery linac

Directory of Open Access Journals (Sweden)

Alexander B. Temnykh

2008-12-01

Full Text Available In anticipation of a new era of synchrotron radiation sources based on energy recovery linac techniques, we designed, built, and tested a short undulator magnet prototype whose features make optimum use of the unique conditions expected in these facilities. The prototype has pure permanent magnet (PPM structure with 24 mm period, 5 mm diameter round gap, and is 30 cm long. In comparison with conventional undulator magnets it has the following: (i full x-ray polarization control.—It may generate varying linear polarized as well as left and right circular polarized x rays with photon flux much higher than existing Apple-II–type devices. (ii 40% stronger magnetic field in linear and approximately 2 times stronger in circular polarization modes. This advantage translates into higher x-ray flux. (iii Compactness.—The prototype can be enclosed in a ∼20  cm diameter cylindrical vacuum vessel. These advantages were achieved through a number of unconventional approaches. Among them is control of the magnetic field strength via longitudinal motion of the magnet arrays. The moving mechanism is also used for x-ray polarization control. The compactness is achieved using a recently developed permanent magnet soldering technique for fastening PM blocks. We call this device a “Delta” undulator after the shape of its PM blocks. The presented article describes the design study, various aspects of the construction, and presents some test results.

What is an energy recovery linac, and why there might be one in your future

Energy Technology Data Exchange (ETDEWEB)

Krafft, Geoffrey [Jefferson Laboratory, Newport News, VA (United States); Old Dominion University, Norfolk, VA (United States)

2016-07-01

Applying beam energy recovery allows a class of novel accelerators to be built with performance characteristics beyond that possible in ring accelerators or non-recirculated linear accelerators. Although the idea was published 50 years ago, and was explored and developed as a result of ''Star Wars'' strategic defense programs in the 1980s and 1990s, renewed interest in energy recovery linacs (ERLs) has flowered as a result of continuous development and improvement of superconducting beam acceleration systems. Many applications to electron accelerators where the very best beam quality is required at high average current have been and are being explored. Examples include advanced X-ray sources, electron sources for electron ion colliders, internal target experiments and applications, lithography, and other topics. Examples highlighting new performance possibilities and the present perception on the limits of ERLs are given.

High duty factor plasma generator for CERN's Superconducting Proton Linac.

Science.gov (United States)

Lettry, J; Kronberger, M; Scrivens, R; Chaudet, E; Faircloth, D; Favre, G; Geisser, J-M; Küchler, D; Mathot, S; Midttun, O; Paoluzzi, M; Schmitzer, C; Steyaert, D

2010-02-01

CERN's Linac4 is a 160 MeV linear accelerator currently under construction. It will inject negatively charged hydrogen ions into CERN's PS-Booster. Its ion source is a noncesiated rf driven H(-) volume source directly inspired from the one of DESY and is aimed to deliver pulses of 80 mA of H(-) during 0.4 ms at a 2 Hz repetition rate. The Superconducting Proton Linac (SPL) project is part of the luminosity upgrade of the Large Hadron Collider. It consists of an extension of Linac4 up to 5 GeV and is foreseen to deliver protons to a future 50 GeV synchrotron (PS2). For the SPL high power option (HP-SPL), the ion source would deliver pulses of 80 mA of H(-) during 1.2 ms and operate at a 50 Hz repetition rate. This significant upgrade motivates the design of the new water cooled plasma generator presented in this paper. Its engineering is based on the results of a finite element thermal study of the Linac4 H(-) plasma generator that identified critical components and thermal barriers. A cooling system is proposed which achieves the required heat dissipation and maintains the original functionality. Materials with higher thermal conductivity are selected and, wherever possible, thermal barriers resulting from low pressure contacts are removed by brazing metals on insulators. The AlN plasma chamber cooling circuit is inspired from the approach chosen for the cesiated high duty factor rf H(-) source operating at SNS.

Progress update on cryogenic system for ARIEL E-linac at TRIUMF

International Nuclear Information System (INIS)

Koveshnikov, A.; Bylinskii, I.; Hodgson, G.; Yosifov, D.

2014-01-01

TRIUMF is involved in a major upgrade. The Advanced Rare IsotopeE Laboratory (ARIEL) has become a fully funded project in July 2010. A 10 mA 50 MeV SRF electron linac (e-linac) operating CW at 1.3 GHz is the key component of this initiative. This machine will serve as a second independent photo-fission driver for Rare Isotope Beams (RIB) production at TRIUMF's Isotope Separator and Accelerator (ISAC) facility. The cryogens delivery system requirements are driven by the electron accelerator cryomodule design [1, 2]. Since commencement of the project in 2010 the cryogenic system of e-linac has moved from the conceptual design phase into engineering design and procurement stage. The present document summarizes the progress in cryogenic system development and construction. Current status of e-linac cryogenic system including details of LN 2 storage and delivery systems, and helium subatmospheric (SA) system is presented. The first phase of e-linac consisting of two cryomodules, cryogens storage, delivery, and distribution systems, and a 600 W class liquid helium cryoplant is scheduled for installation and commissioning by year 2014

Upgrade of the ISIR L-band linac at Osaka University and stabilization of the electron beam

International Nuclear Information System (INIS)

Kato, R.; Kashiwagi, S.; Yamamoto, T.; Suemine, S.; Isoyama, G.

2004-01-01

The L-band electron linac at the Institute of Scientific and Industrial Research, Osaka University has been extensively remodeled to realize high operational stability and reproducibility for advanced studies in beam science and technology. Almost all the peripheral components are replaced with new ones. The modification of the linac has been completed and commissioning is now in progress. In this paper, we will report performance and characteristics of the linac after modification. (author)

Florida State University superconducting linac

International Nuclear Information System (INIS)

Myers, E.G.; Fox, J.D.; Frawley, A.D.; Allen, P.; Faragasso, J.; Smith, D.; Wright, L.

1988-01-01

As early as the fall of 1977 it was decided that the future research needs of their nuclear structure laboratory required an increase in energy capability to at least 8 MeV per nucleon for the lighter ions, and that these needs could be met by the installation of a 17 MV tandem Van de Graaff accelerator. The chief problem with this proposal was the high cost. It became apparent that a far less expensive option was to construct a linear accelerator to boost the energy from their existing 9 MV tandem. The options open to them among linac boosters were well represented by the room temperature linac at Heidelberg and the superconducting Stony Brook and Argonne systems. By the Spring of 1979 it had been decided that both capital cost and electric power requirements favored a superconducting system. As regards the two superconducting resonator technologies - the Argonne niobium-copper or the Caltech-Stony Brook lead plated copper - the Argonne resonators, though more expensive to construct, had the advantages of more boost per resonator, greater durability of the superconducting surface and less stringent beam bunching requirements. In 1980 pilot funding from the State of Florida enabled the construction of a building addition to house the linac and a new target area, and the setting up of a small, three resonator, test booster. Major funding by the NSF for the laboratory upgrade started in 1984. With these funds they purchased their present helium liquefaction and transfer system and constructed three large cryostats, each housing four Argonne beta = 0.105 resonators and two superconducting solenoids. The last large cryostat was completed and installed on-line early this year and the linac was dedicated on March 20. Nuclear physics experiments using the whole linac began in early June. 4 references, 6 figures, 1 table

Superhilac upgrade project

International Nuclear Information System (INIS)

Feinberg, B.; Brown, I.G.

1985-05-01

This project will increase the uranium output of the Bevalac heavy-ion facility from the currently available 10 7 to 5 x 10 7 ions/pulse, allowing accurate Lamb shift measurements to be made in U 90+ and U 91+ with important applications to the testing of quantum electrodynamics and the development of an x-ray laser. The injected beam intensity will be increased to make better use of the 10emA output space-charge limit of the Wideroe linac. Components will include a new high current MEtal Vapor Vacuum Arc (MEVVA) ion source along with an improved high current, high voltage Cockcroft-Walton power supply to handle the increased beam current. The Low Energy Beam Transport (LEBT) line will be upgraded with additional focusing to manage the increased space-charge forces and with an improved vacuum to reduce charge exchange losses. Finally, the phase matching between the 23MHz Wideroe linac and the 70MHz Alvarez linac will be improved by the addition of the appropriate buncher cavities. Physics design is underway and detailed engineering is scheduled to begin in October 1985, with installation slated for the 1986 summer shutdown

Finite Element Thermal Study of the Linac4 Plasma Generatora

CERN Document Server

Faircloth, D; Kuchler, D; Lettry, L; Scrivens, R; CERN. Geneva. BE Department

2010-01-01

The temperature distribution and heat flow at equilibrium of the plasma generator of the RF-powered non-cesiated Linac4 H- ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW RF power, 2 Hz, 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of SPL, an extrapolation of the heat load towards 100 kW RF power, 50 Hz repetition rate and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in HP-SPL.

Linac4, a New Injector for the CERN PS Booster

CERN Document Server

Garoby, R; Gerigk, F; Hanke, K; Lombardi, A; Pasini, M; Rossi, C; Sargsyan, E; Vretenar, M

2006-01-01

The first bottle-neck towards higher beam brightness in the LHC injector chain is due to space charge induced tune spread at injection into the CERN PS Booster (PSB). A new injector called Linac4 is proposed to remove this limitation. Using RF cavities at 352 and 704 MHz, it will replace the present 50 MeV proton Linac2, and deliver a 160 MeV, 40 mA H- beam. The higher injection energy will reduce space charge effects by a factor of 2, and charge exchange will drastically reduce the beam losses at injection. Operation will be simplified and the beam brightness required for the LHC ultimate luminosity should be obtained at PS ejection. Moreover, for the needs of non-LHC physics experiments like ISOLDE, the number of protons per pulse from the PSB will increase by a significant factor. This new linac constitutes an essential component of any of the envisaged LHC upgrade scenarios. It is also designed to become the low energy part of a future 3.5 GeV, multi-megawatt superconducting linac (SPL). The present desig...

Update on the VECC-TRIUMF collaboration for superconducting e-Linac development

International Nuclear Information System (INIS)

Naik, V.; Dechoudhury, S.; Mondal, M.

2013-01-01

A 50 MeV 100 kW cw superconducting electron linac (e-Linac) will be used as photo-fission driver for the ANURIB facility at Variable Energy Cyclotron Centre. In the first phase a 10 MeV Injector is being developed in collaboration with TRIUMF Canada, who will also be using an e-Linac driver for their ARIEL (Advanced Rare IsotopE Laboratory) upgrade. The VECC e-Linac will be installed at the upcoming Rajarhat campus. For the initial R and D on the Injector an e-Linac test area is being set-up in one of the experimental caves of the K130 cyclotron at the Salt Lake campus. The Injector will be tested using a 100 kV gun. A Capture Cryo Module (CCM) consisting of two beta=1, 1.3 GHz, single-cell niobium cavities is being designed and built indigenously. The CCM will be used for pre-acceleration of the beam from the gun to around 400 keV before injection in to the ICM. The ICM will be built and tested at TRIUMF and a test area has been set-up at TRIUMF for the purpose. Detailed status report on various components of the e-Linac will be presented. (author)

Optimization of Beam Transmission of PAL-PNF Electron Linac

Energy Technology Data Exchange (ETDEWEB)

Shin, S. G.; Kim, S. K.; Kim, E. A. [Pohang University of Science and Technology, Pohang (Korea, Republic of)

2012-05-15

The PNF (Pohang Neutron Facility) electron Linac is providing converted neutrons and photons from electron beams to users for nuclear physics experiments and high energy gamma-ray exposures. This linac is capable of producing 100 MeV electron beams with a beam current of pulsed 100 mA. The pulse length is 2 {mu}s and the pulse repetition rate is typically 30 Hz. This linac consists of two SLAC-type S-band accelerating columns and the thermionic RF gun. They are powered by one klystron and the matching pulse modulator. The electron beams emitted from the RF gun are bunched as they pass through the alpha magnet and are injected into the accelerating column thereafter. In this paper, we discuss procedures and results of the beam transmission optimization with technical details of the accelerator system. We also briefly discuss the future upgrade plan to obtain short-pulse or electron beams for neutron TOF experiments by adopting a triode type thermionic DC electron gun

Progress update on cryogenic system for ARIEL E-linac at TRIUMF

Energy Technology Data Exchange (ETDEWEB)

Koveshnikov, A.; Bylinskii, I.; Hodgson, G.; Yosifov, D. [TRIUMF, Vancouver, BC, V6T 2A3 (Canada)

2014-01-29

TRIUMF is involved in a major upgrade. The Advanced Rare IsotopeE Laboratory (ARIEL) has become a fully funded project in July 2010. A 10 mA 50 MeV SRF electron linac (e-linac) operating CW at 1.3 GHz is the key component of this initiative. This machine will serve as a second independent photo-fission driver for Rare Isotope Beams (RIB) production at TRIUMF's Isotope Separator and Accelerator (ISAC) facility. The cryogens delivery system requirements are driven by the electron accelerator cryomodule design [1, 2]. Since commencement of the project in 2010 the cryogenic system of e-linac has moved from the conceptual design phase into engineering design and procurement stage. The present document summarizes the progress in cryogenic system development and construction. Current status of e-linac cryogenic system including details of LN{sub 2} storage and delivery systems, and helium subatmospheric (SA) system is presented. The first phase of e-linac consisting of two cryomodules, cryogens storage, delivery, and distribution systems, and a 600 W class liquid helium cryoplant is scheduled for installation and commissioning by year 2014.

RF upgrade program in LHC injectors and LHC machine

International Nuclear Information System (INIS)

Jensen, E.

2012-01-01

The main themes of the RF upgrade program are: the Linac4 project, the LLRF-upgrade and the study of a tuning-free wide-band system for PSB, the upgrade of the SPS 800 MHz amplifiers and beam controls and the upgrade of the transverse dampers of the LHC. Whilst LHC Splice Consolidation is certainly the top priority for LS1, some necessary RF consolidation and upgrade is necessary to assure the LHC performance for the next 3- year run period. This includes: 1) necessary maintenance and consolidation work that could not fit the shorter technical stops during the last years, 2) the upgrade of the SPS 200 MHz system from presently 4 to 6 cavities and possibly 3) the replacement of one LHC cavity module. On the longer term, the LHC luminosity upgrade requires crab cavities, for which some preparatory work in SPS Coldex must be scheduled during LS1. (author)

CERN Linac4. The space charge challenge

Energy Technology Data Exchange (ETDEWEB)

Hein, Lutz Matthias

2013-08-06

In the first phase of the upgrade program of the CERN accelerator complex the proton injector Linac2 will be replaced by a new, normal-conducting H-ion Linac, Linac4, allowing a significant increase of the proton flux intensity along the downstream accelerator complex. In the design of Linac4 three beam transport sections are implemented to match the beam between the different accelerator elements and to model the longitudinal pulse structure. These three beam transport sections, which are the most critical locations in terms of beam quality preservation, are in the focus of this thesis. During the work of this thesis the Low Energy Beam Transport (LEBT), which is required to match the source beam to the radiofrequency quadrupole (RFQ), has been commissioned and its beam dynamics re-constructed. The measurement campaign used to reconstruct the LEBT beam dynamics was performed with the aim to prepare the RFQ commissioning and to maximise the LEBT performance. Downstream of the Linac4 accelerator the beam is transported along a 180 m long transfer line to the Proton Synchrotron Booster (PS-Booster). The transfer line optics was studied, optimised and sections were completely re-designed. The new transfer line optics is characterised by an improved preservation of the beam emittance, higher stability of the optical solution with respect to alignment errors and field jitters of the transfer line magnets and it is matched to each of the PS-Booster injection schemes. In a concluding ''Start-To-End'' simulation based on the measured beam characteristics at the LEBT exit the beam dynamics of the downstream Linac, including the transfer line, was calculated. To minimise particle losses within acceptable emittance preservation the beam optics of the Medium Energy Beam Transport (MEBT) was adapted to the measured beam parameters. This ''Start-To-End'' simulation was performed to identify critical sections of the Linac4 beam dynamics and

Design, realization and test of C-band accelerating structures for the SPARC-LAB linac energy upgrade

International Nuclear Information System (INIS)

Alesini, D.; Bellaveglia, M.; Biagini, M.E.; Boni, R.; Brönnimann, M.; Cardelli, F.; Chimenti, P.; Clementi, R.; Di Pirro, G.; Di Raddo, R.; Ferrario, M.; Ficcadenti, L.; Gallo, A.; Kalt, R.; Lollo, V.; Palumbo, L.; Piersanti, L.; Schilcher, T.

2016-01-01

The energy upgrade of the SPARC-LAB photo-injector at LNF-INFN (Frascati, Italy) has been originally conceived replacing one low gradient (13 MV/m) 3 m long SLAC type S-band traveling wave (TW) section with two 1.4 m long C-band accelerating sections. Due to the higher gradients reached by such structures, a higher energy beam can be obtained within the same accelerator footprint length. The use of C-band structures for electron acceleration has been adopted in a few FEL linacs in the world, among others, the Japanese Free Electron Laser at SPring-8 and the SwissFEL at Paul Scherrer Institute (PSI). The C-band sections are traveling wave, constant impedance structures with symmetric input and output axial couplers. Their design has been optimized for the operation with a SLED RF pulse compressor. In this paper we briefly review their design criteria and we focus on the construction, tuning, low and high-power RF tests. We also illustrate the design and realization of the dedicated low level RF system that has been done in collaboration with PSI in the framework of the EU TIARA project. Preliminary experimental results appear to confirm the operation of such structures with accelerating gradients larger than 35 MV/m.

Design, realization and test of C-band accelerating structures for the SPARC-LAB linac energy upgrade

Energy Technology Data Exchange (ETDEWEB)

Alesini, D.; Bellaveglia, M.; Biagini, M.E.; Boni, R. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Brönnimann, M. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Cardelli, F. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Chimenti, P.; Clementi, R.; Di Pirro, G.; Di Raddo, R.; Ferrario, M. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Ficcadenti, L. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Gallo, A. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Kalt, R. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Lollo, V. [INFN Laboratori Nazionali di Frascati, Via Enrico Fermi 40, 00044, Frascati (Italy); Palumbo, L. [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Piersanti, L., E-mail: luca.piersanti@lnf.infn.it [INFN Sezione di Roma, P.le Aldo Moro 2, 00185, Roma (Italy); Università di Roma “La Sapienza”, P.le Aldo Moro 2, 00185, Roma (Italy); Schilcher, T. [Paul Scherrer Institut, 5232 Villigen (Switzerland)

2016-11-21

The energy upgrade of the SPARC-LAB photo-injector at LNF-INFN (Frascati, Italy) has been originally conceived replacing one low gradient (13 MV/m) 3 m long SLAC type S-band traveling wave (TW) section with two 1.4 m long C-band accelerating sections. Due to the higher gradients reached by such structures, a higher energy beam can be obtained within the same accelerator footprint length. The use of C-band structures for electron acceleration has been adopted in a few FEL linacs in the world, among others, the Japanese Free Electron Laser at SPring-8 and the SwissFEL at Paul Scherrer Institute (PSI). The C-band sections are traveling wave, constant impedance structures with symmetric input and output axial couplers. Their design has been optimized for the operation with a SLED RF pulse compressor. In this paper we briefly review their design criteria and we focus on the construction, tuning, low and high-power RF tests. We also illustrate the design and realization of the dedicated low level RF system that has been done in collaboration with PSI in the framework of the EU TIARA project. Preliminary experimental results appear to confirm the operation of such structures with accelerating gradients larger than 35 MV/m.

Source and LINAC3 studies

CERN Document Server

Bellodi, G

2017-01-01

In the framework of the LHC Ion Injector Upgrade pro-gramme (LIU), several activities have been carried out in2016 to improve the ion source and Linac3 performance,with the goal to increase the beam current routinely deliv-ered to LEIR. The extraction region of the GTS-LHC ionsource was upgraded with enlarged vacuum chamber aper-tures and the addition of an einzel lens, yielding highertransmission through the rest of the machine. Also, a seriesof experiments have been performed to study the effects ofdouble frequency mixing on the afterglow performance ofthe source after installation of a Travelling Wave Tube Am-plifier (TWTA) as secondary microwave source at variablefrequency. Measurements have been carried out at a dedi-cated oven test stand for better understanding of the ionsource performance. Finally, several MD sessions werededicated to the study and characterization of the strippingfoils, after evidence of degradation in time was discoveredin the 2015 run.

RF system developments for CW and/or long pulse linacs

International Nuclear Information System (INIS)

Lynch, M.

1998-01-01

High Power Proton Linacs are under development or proposed for development at Los Alamos and elsewhere. By current standards these linacs all require very large amounts of RF power. The Accelerator for Production of Tritium (APT) is a CW accelerator with an output current and energy of 100 mA and 1,700 MeV, respectively. The Spallation Neutron Source (SNS), in its ultimate configuration, is a pulsed accelerator with an average output power of 4 MW of beam. Other accelerators such as those that address transmutation and upgrades to LANSCE have similar requirements. For these high average power applications, the RF systems represent approximately half of the total cost of the linac and are thus key elements in the design and configuration of the accelerator. Los Alamos is fortunate to be actively working on both APT and SNS. For these programs the author is pursuing a number of component developments which are aimed at one or more of the key issues for large RF systems: technical performance, capital cost, reliability, and operating efficiency. This paper briefly describes some of the linac applications and then provides updates on the key RF developments being pursued

A test beam upgrade based on the BEPC-LINAC

International Nuclear Information System (INIS)

Li Jiacai; Wu Yuanming; Cui Xiangzong; Zhang Liangsheng; Zhou Baoqing; Liu Zhengquan; Zhang Shaoping; Sun Changchun; Zhang Zhuxiang; Zhang Caidi; Zheng Linsheng; Liu Shixing; Shen Ji; Yin Zejie; Zhang Yongming; Chen Ziyu

2004-01-01

A total of three beam lines, E1, E2 and E3 have based on the LINAC of BEPC. The E1 beam is to be used for intense slow-positron facility. The E2 is a primary positron or electron beam with an energy of 1.3-1.5 GeV. The E3 is a secondary electron or pion test beam with a momentum can be adjustable continuously. The position accuracy of a detected particle is 0.2-0.4 mm with an event rate of 3 - 4 Hz. This beam has been successfully used for some detectors beam test. (author)

Beam dynamics and commissioning of low and medium energy H- beam at Linac4

CERN Document Server

Satri, Masoomeh Yarmohammadi; Lombardi, Alessandra; Lamehi-Rachti , Mohammad

The First step of the CERN Large Hadron Collider injectors upgrade (LIU) project is Linac4. It accelerates H- ions to 160 MeV in an 80 m long accelerator housed in a tunnel 12 m underground, presently under construction. It will replace the present 50 MeV proton Linac2 as injector of the proton accelerator complex to increase the LHC luminosity. It consists of a 45 keV RF volume source, a twosolenoid Low Energy Beam Transport (LEBT), a 352.2 MHz Radio Frequency Quadrupole (RFQ) accelerating the beam to 3 MeV, a Medium Energy Beam Transport (MEBT) line. The MEBT houses a fast chopper to selectively remove unwanted micro-bunches in the 352 MHz sequence and avoid losses at capture in the CERN PSB (1 MHz). After chopping, the beam acceleration continues by a 50 MeV Drift Tube Linac (DTL), a 100 MeV Cell-Coupled Drift Tube Linac and a Pi-Mode Structure bringing the beam to the final energy of 160 MeV. Linac4 has been commissioned with a temporary source up to 12 MeV. The beam commissioning stages of Linac4 in LEBT...

Design of a Marx-Topology Modulator for FNAL Linac

Energy Technology Data Exchange (ETDEWEB)

Butler, T. A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Garcia, F. G. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Kufer, M. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Pfeffer, H. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Wolff, D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

2015-04-28

The Fermilab Proton Improvement Plan (PIP) was formed in late 2011 to address important and necessary upgrades to the Proton Source machines (Injector line, Linac and Booster). The goal is to increase the proton flux by doubling the Booster beam cycle rate while maintaining the same intensity per cycle, the same uptime, and the same residual activation in the enclosure. For the Linac, the main focus within PIP is to address reliability. One of the main tasks is to replace the present hard-tube modulator used on the 200 MHz RF system. Plans to replace this high power system with a Marx-topology modulator, capable of providing the required waveform shaping to stabilize the accelerating gradient and compensate for beam loading, will be presented, along with development data from the prototype unit.

Klystron modulator operation and upgrades for the APS linac

International Nuclear Information System (INIS)

Russell, T.J.; Cours, A.

1995-01-01

The Advanced Photon Source (APS) linac requires five 100-MW modulators to achieve its required energy. In-house construction of these modulators was under an extremely compressed time schedule and, while the original design was successful, it had a few shortcomings. The operation of the modulators was hindered by excessively sensitive controls and overheating during the hot summer months. The system underwent minor changes that resulted in major improvements. Additionally, improvements have been made to the high voltage circuits to improve the rise time of the output pulse shape. reduce the initial ringing of the pulse, and enhance the reliability of the system. This paper will outline the changes and explain the results of the improvements

Kansas State University accelerator laboratory upgrade

International Nuclear Information System (INIS)

Richard, P.

1989-01-01

The J.R. Macdonald Laboratory is undergoing a major upgrade of its facilities and capabilities. The laboratory is dedicated to the study of ion-atom collisions using highly charged ions from accelerators and/or ion sources. The mainstay of the laboratory over the last two decades has been a 6 MV tandem accelerator. It has been used to produce one- to a few-MeV/u highly charged ions for studying high energy atomic collisions, and to produce recoil ions from ocllisions with projectile ions for studying low energy atomic collisions. In order to enhance the capabilities of studying atomic collisions in these two energy regimes, we are constructing a superconducting LINAC booster to the tandem, and a stand-alone CRYEBIS source. The project, which is funded by the US Department of Energy, began in May 1985 with a May 1989 completion schedule. The upgrade includes a building addition, funded by the State of Kansas, to house the new facilities. The LINAC consists of a time-superbunching module, followed by three large cryostat modules each containing four superconducting resonators, and followed by an energy-rebunching module. The resonators are the split-ring superconducting Nb type designed and constructed at Argonne National Laboratory, and are presently being tested at KSU. The CRYEBIS source, which consists of a 1 m long 5 T superconducting solenoid with a high degree of straightness, is in the final stages of assembly. We have in operation a new computer network for data acquisition and analysis. A progress report on the status of the upgrade is presented. (orig.)

HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

International Nuclear Information System (INIS)

Girish Srinivas; Steven C. Gebhard; David W. DeBerry

2001-01-01

This first quarter report of 2001 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H(sub 2)S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf(trademark) (service mark of Gas Research Institute) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H(sub 2)S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H(sub 2)S in the natural gas is first oxidized to SO(sub 2) at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H(sub 2)S can be oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. During this reporting periods new catalyst formulations were tested. The experiments showed that the newest catalyst has slightly better performance, but catalyst TDA No.2 is still superior overall for use with the hybrid CrystaSulf process due to lower costs. Plans for catalyst pelletization and continued testing are described

Auto-tuning systems for J-PARC LINAC RF cavities

International Nuclear Information System (INIS)

Fang, Z.; Kobayashi, T.; Fukui, Y.; Futatsukawa, K.; Michizono, S.; Yamaguchi, S.; Anami, S.; Suzuki, H.; Sato, F.; Shinozaki, S.; Chishiro, E.

2014-01-01

The 400-MeV proton linear accelerator (LINAC) at the Japan Proton Accelerator Research Complex (J-PARC) consists of 324-MHz low-β and 972-MHz high-β accelerator sections. From October 2006 to May 2013, only the 324-MHz low-β accelerator section was in operation. From the summer of 2013 the J-PARC LINAC was upgraded by installing the 972-MHz high-β accelerator section, and the proton beam was successfully accelerated to 400 MeV in January 2014. Auto-tuning systems for the J-PARC LINAC RF cavities have been successfully developed. A first generation design, an auto-tuning system using a mechanical tuner controller, was developed and operated for the first 3 years. Then the second-generation auto-tuning system was developed using a new approach to the RF cavity warm-up process, and this was applied to the accelerator operation for the subsequent 4 years. During the RF cavity warm-up process in this system, the mechanical tuner is constantly fixed and the input RF frequency is automatically tuned to the cavity resonance frequency using the FPGA (Field-Programmable Gate Array) of the digital feedback RF control system. After the input power level reaches the required value, input RF frequency tuning is stopped and it is switched to the operation frequency. Then, the mechanical tuner control begins operation. This second-generation auto-tuning system was extremely effective for the 324-MHz cavity operation. However, if we apply this approach to the 972-MHz RF cavities, an interlock due to the RF cavity reflection amplitude occasionally occurs at the end of the warm-up process. In order to solve this problem a third generation novel auto-tuning system was successfully developed in December 2013 and applied to the operation of the J-PARC LINAC, including the 972-MHz ACS RF cavities. During the warm-up process both the mechanical tuner controller and the input RF frequency tuning are in operation, and good matching between the input RF frequency and the RF cavity is

Auto-tuning systems for J-PARC LINAC RF cavities

Energy Technology Data Exchange (ETDEWEB)

Fang, Z., E-mail: fang@post.kek.jp [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Kobayashi, T.; Fukui, Y.; Futatsukawa, K.; Michizono, S.; Yamaguchi, S.; Anami, S. [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Suzuki, H.; Sato, F.; Shinozaki, S.; Chishiro, E. [Japan Atomic Energy Agency (JAEA), 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)

2014-12-11

The 400-MeV proton linear accelerator (LINAC) at the Japan Proton Accelerator Research Complex (J-PARC) consists of 324-MHz low-β and 972-MHz high-β accelerator sections. From October 2006 to May 2013, only the 324-MHz low-β accelerator section was in operation. From the summer of 2013 the J-PARC LINAC was upgraded by installing the 972-MHz high-β accelerator section, and the proton beam was successfully accelerated to 400 MeV in January 2014. Auto-tuning systems for the J-PARC LINAC RF cavities have been successfully developed. A first generation design, an auto-tuning system using a mechanical tuner controller, was developed and operated for the first 3 years. Then the second-generation auto-tuning system was developed using a new approach to the RF cavity warm-up process, and this was applied to the accelerator operation for the subsequent 4 years. During the RF cavity warm-up process in this system, the mechanical tuner is constantly fixed and the input RF frequency is automatically tuned to the cavity resonance frequency using the FPGA (Field-Programmable Gate Array) of the digital feedback RF control system. After the input power level reaches the required value, input RF frequency tuning is stopped and it is switched to the operation frequency. Then, the mechanical tuner control begins operation. This second-generation auto-tuning system was extremely effective for the 324-MHz cavity operation. However, if we apply this approach to the 972-MHz RF cavities, an interlock due to the RF cavity reflection amplitude occasionally occurs at the end of the warm-up process. In order to solve this problem a third generation novel auto-tuning system was successfully developed in December 2013 and applied to the operation of the J-PARC LINAC, including the 972-MHz ACS RF cavities. During the warm-up process both the mechanical tuner controller and the input RF frequency tuning are in operation, and good matching between the input RF frequency and the RF cavity is

Electron bunch structure in energy recovery linac with high-voltage dc photoelectron gun

Directory of Open Access Journals (Sweden)

Y. M. Saveliev

2016-09-01

Full Text Available The internal structure of electron bunches generated in an injector line with a dc photoelectron gun is investigated. Experiments were conducted on the ALICE (accelerators and lasers in combined experiments energy recovery linac at Daresbury Laboratory. At a relatively low dc gun voltage of 230 kV, the bunch normally consisted of two beamlets with different electron energies, as well as transverse and longitudinal characteristics. The beamlets are formed at the head and the tail of the bunch. At a higher gun voltage of 325 kV, the beam substructure is much less pronounced and could be observed only at nonoptimal injector settings. Experiments and computer simulations demonstrated that the bunch structure develops during the initial beam acceleration in the superconducting rf booster cavity and can be alleviated either by increasing the gun voltage to the highest possible level or by controlling the beam acceleration from the gun voltage in the first accelerating structure.

Linac4 Low Energy Beam Measurements with Negative Hydrogen

CERN Document Server

Scrivens, R; Crettiez, O; Dimov, V; Gerard, D; Granemann Souza, E; Guida, R; Hansen, J; Lallement, J B; Lettry, J; Lombardi, A; Midttun, O; Pasquino, C; Raich, U; Riffaud, B; Roncarolo, F; Valerio-Lizarraga, C A; Wallner, J; Yarmohammadi Satri, M; Zickler, T

2014-01-01

Linac4, a 160 MeV normal-conducting H- linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H- beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

Recent technological advances in the application of nano-catalytic technology to the enhanced recovery and upgrading of bitumen and heavy oils

Energy Technology Data Exchange (ETDEWEB)

Pereira Almao, P. [Calgary Univ., AB (Canada). Schulich School of Engineering

2013-11-01

Advances in Nanotechnology, such as manufacturing of nano-catalysts allow the online (during processing) and on site production of nano-catalysts for heavy oils upgrading. These inventions have also facilitated the development of two lines of heavy oils upgrading processes that make use of nano-catalysts for producing upgraded oil: In Situ Upgrading and Field Upgrading. Producing chemical upgrading of heavy oils is achievable and economically viable at lower temperatures and lower pressures than used in most upgraders if the use of nano-catalysts were implemented. The spontaneity of thermal, steam and hydro processing reactions for converting the different chemical families of hydrocarbons present in the heaviest fractions of heavy oils and bitumen (HO-B) into lighter products was shown recently. Spontaneity was measured by the value of the change of free energy at low pressure. These undesirable paths are spontaneous and uncontrollable under thermal cracking conditions, and require providing years of residence time for intermolecular hydrogen redistribution to minimize olefins polymerization, if at all possible. Instead, hydroprocessing in the presence of hydrogen activating catalysts would create an abundance of hydrogen radicals impeding large molecules condensation and olefins proliferation. In Situ Upgrading: performs coupled Enhanced Oil Recovery with In Reservoir Upgrading via Hot Fluid Injection (HFI). The heat handling of this HFI process and the production of transportable oil with no need of diluent from the start of operation completes the originality of it. This technology uses heavy fractions separated from produced oil to reintroduce heat into the reservoir along with suspended nano-catalysts and hydrogen. These components react in the well bore and inside the reservoir to release more heat (hydroprocessing reactions are exothermic) producing light gases and volatile hydrocarbons that contribute to increase oil detachment from the rock resulting in

Use of an INR-style bunch-length detector in the Fermilab Linac

International Nuclear Information System (INIS)

McCrory, E.S.; Schmidt, C.W.; Feschenko, A.V.

1993-01-01

Device to accurately measure the phase extent of a linac beam is being developed for use in the Fermilab 400 MeV Linac Upgrade. Prototypes have been and are being tested. We have attempted to improve the original design from the Institute for Nuclear Research in Moscow (INR) to increase the resolution for adequate operation at 805 MHz. The device incorporating a new arrangement of lens and deflector, reported previously, cannot achieve the desired resolution. This paper describes the operation and the strengths and weaknesses of the three types of bunch-length detectors (BLDs) and the measurements made at this time. The differences among these devices is delineated by the relative position of the rf deflector and the electrostatic einsel lens, as follows: INR--Lens before deflector; Fermilab--Lens after deflector; H- beam; and FNAL/INR--Lens and deflector combined. To satisfy the goals of commissioning the new linac, a resolution of about 5 picoseconds (1 degree at 805 MHz) is desired

Plans for the upgrade of the LHC injectors

CERN Document Server

Garoby, R; Goddard, B; Hanke, K; Meddahi, M; Vretenar, M

2011-01-01

The LHC injectors upgrade (LIU) project has been launched at the end of 2010 to prepare the CERN accelerator complex for reliably providing beam with the challenging characteristics required by the high luminosity LHC until at least 2030. Based on the work already started on Linac4, PS Booster, PS and SPS, the LIU project coordinates studies and implementation, and interfaces with the high luminosity LHC (HL-LHC) project which looks after the upgrade of the LHC itself, expected by the end of the present decade. The anticipated beam characteristics are described, as well as the status of the studies and the solutions envisaged for improving the injector performances.

LHC Injectors Upgrade (LIU) Project at CERN

CERN Document Server

Shaposhnikova, Elena; Damerau, Heiko; Funken, Anne; Gilardoni, Simone; Goddard, Brennan; Hanke, Klaus; Kobzeva, Lelyzaveta; Lombardi, Alessandra; Manglunki, Django; Mataguez, Simon; Meddahi, Malika; Mikulec, Bettina; Rumolo, Giovanni; Scrivens, Richard; Vretenar, Maurizio

2016-01-01

A massive improvement program of the LHC injector chain is presently being conducted under the LIU project. For the proton chain, this includes the replacement of Linac2 with Linac4 as well as all necessary upgrades to the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS) and Super Proton Synchrotron (SPS), aimed at producing beams with the challenging High Luminosity LHC (HL-LHC) parameters. Regarding the heavy ions, plans to improve the performance of Linac3 and the Low Energy Ion Ring (LEIR) are also pursued under the general LIU program. The full LHC injection chain returned to operation after Long Shutdown 1, with extended beam studies taking place in Run 2. A general project Cost and Schedule Review also took place in March 2015, and several dedicated LIU project reviews were held to address issues awaiting pending decisions. In view of these developments, 2014 and 2015 have been key years to define a number of important aspects of the final LIU path. This paper will describe the reviewed LI...

Redesign of CERN LINAC3 RFQ for Lead 29+

CERN Document Server

Benedetti, Stefano; Lallement, Jean-Baptiste; Lombardi, Alessandra; CERN. Geneva. ATS Department

2018-01-01

CERN Linac3 is at the heart of the CERN Heavy Ion Facility, providing 4.2 MeV/u ion beams to the Low Energy Ion Ring (LEIR). It mostly accelerates 208Pb29+, though in recent years runs were performed with 40Ar11+ and 129Xe22+, in view of the raising interest of the physics community towards lighter ions experiments. In the framework of the LHC Injectors Upgrade (LIU) project, measurements and beam dynamics simulations showed that a transmission bottleneck of Linac3 is represented by the RFQ. As this accelerator was originally designed for 208Pb25+, the lower beam rigidity of the heavy ions currently in used – and planned to be used – permits a redesign of the RFQ aimed at increasing its transverse acceptance, and thus the transmitted beam current. The methodology adopted and the results of this study are presented.

High-brightness electron guns for linac-based light sources

International Nuclear Information System (INIS)

Lewellen, J.W.

2004-01-01

Most proposed linac-based light sources, such as single-pass free-electron lasers and energy-recovery-linacs, require very high-brightness electron beams in order to achieve their design performance. These beam requirements must be achieved not on an occasional basis, but rather must be met by every bunch produced by the source over extended periods of time. It is widely assumed that the beam source will be a photocathode electron gun; the selection of accelerator technique (e.g., dc or rf) for the gun is more dependent on the application.The current state of the art of electron beam production is adequate but not ideal for the first generation of linac-based light sources, such as the Linac Coherent Light Source (LCLS) x-ray free-electron laser (X-FEL). For the next generation of linac-based light sources, an order of magnitude reduction in the transverse electron beam emittance is required to significantly reduce the cost of the facility. This is beyond the present state of the art, given the other beam properties that must be maintained. The requirements for current and future linac-based light source beam sources are presented here, along with a review of the present state of the art. A discussion of potential paths towards meeting future needs is presented at the conclusion.

Space charge compensation on the low energy beam transport of Linac4

CERN Document Server

AUTHOR|(SzGeCERN)733270; Scrivens, Richard; Jesus Castillo, Santos

Part of the upgrade program in the injector chains of the CERN accelerator complex is the replacement of the the proton accelerator Linac2 for the brand new Linac4 which will accelerate H$^-$ and its main goal is to increase the beam intensity in the next sections of the LHC accelerator chain. The Linac4 is now under commissioning and will use several ion sources to produce high intensity unbunched H$^-$ beams with different properties, and the low energy beam transport (LEBT) is the system in charge of match all these different beams to the Radio frequency quadrupole (RFQ). The space charge forces that spread the beam ions apart of each other and cause emittance growth limits the maximum intensity that can be transported in the LEBT, but the space charge of intense unbunched ion beams can be compensated by the generated ions by the impact ionization of the residual gas, which creates a source of secondary particles inside the beam pipe. For negative ion beams, the effect of the beam electric field is to ex...

Improved performance of the control scheme for IUAC superconducting Linac

International Nuclear Information System (INIS)

Sahu, B.K.; Suman, S.K.; Kumar, R.

2015-01-01

Since many years energized ion beams from linac are being delivered routinely for scheduled experiments using all the three accelerating modules of linac along with super buncher and rebuncher. Major efforts are dedicated to improve the performance of the control scheme to minimise the down time of the linac during operation. Earlier, a number of developments were carried out to improve the dynamics of the control scheme. The most significant of them is the piezoelectric actuator based tuning mechanism which is implemented in all the operational resonators of second and third accelerating modules of superconducting linac. This has helped us to bridge the gap between the accelerating fields achieved during Q measurement at 6 W of helium power and during phase locking of the resonator during beam operation at a given RF power (∼120W). The piezoelectric actuator based tuner is also instrumental to reduce the unlocking rate of the resonators. Pulse width modulation (PWM) control based helium gas operated tuner is implemented in few resonators to improve phase locking performance. CAMAC based distributed control scheme is upgraded to VME based distributed control without changing the existing client interface to maintain uniformity between the Pelletron and linac control. Python code support has been implemented to protect the resonators against high forward power during unlocking. This is also integrated with the display status of the resonators for monitoring. A frequency to voltage converter is incorporated in control scheme to monitor the frequency error. This has helped us to develop a scheme for automatic phase locking of the cavities using piezoelectric actuator based tuner control. (author)

Linac4 low energy beam measurements with negative hydrogen ions

Energy Technology Data Exchange (ETDEWEB)

Scrivens, R., E-mail: richard.scrivens@cern.ch; Bellodi, G.; Crettiez, O.; Dimov, V.; Gerard, D.; Granemann Souza, E.; Guida, R.; Hansen, J.; Lallement, J.-B.; Lettry, J.; Lombardi, A.; Midttun, Ø.; Pasquino, C.; Raich, U.; Riffaud, B.; Roncarolo, F.; Valerio-Lizarraga, C. A.; Wallner, J.; Yarmohammadi Satri, M.; Zickler, T. [CERN, 1211 Geneva 23 (Switzerland)

2014-02-15

Linac4, a 160 MeV normal-conducting H{sup −} linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ (Radiofrequency Quadrupole) has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H{sup −} beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

International Nuclear Information System (INIS)

Girish Srinivas; Steven C. Gebhard; David W. DeBerry

2002-01-01

This first quarter report of 2002 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H(sub 2)S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf(sup SM) (service mark of CrystaTech, Inc.) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H(sub 2)S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H(sub 2)S in the natural gas is first oxidized to SO(sub 2) at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H(sub 2)S can be oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. In a previous reporting period tests were done to determine the effect of hydrocarbons such as n-hexane on catalyst performance with and without H(sub 2)S present. The experiments showed that hexane oxidation is suppressed when H(sub 2)S is present. Hexane represents the most reactive of the C1 to C6 series of alkanes. Since hexane exhibits low reactivity under H(sub 2)S oxidation conditions, and more importantly, does not change

SNS superconducting linac

International Nuclear Information System (INIS)

Sundelin, Ronald M.

2001-01-01

The Spallation Neutron Source (SNS) decided in early 2000 to use superconducting RF (SRF) in the linac at energies above 185 MeV. Since the SNS duty cycle is 6%, the SRF and normal conducting approaches have capital costs which are about the same, but operating costs and future upgradability are improved by using SRF. The current status of cavity and cryomodule development and procurement, including the basis for decisions made, is discussed. The current plan includes use of 805 MHz, 6-cell cavities with geometrical betas of 0.61 and 0.81. There are 33 medium beta and 60 high beta cavities in 11 and 15 cryomodules, respectively. Each cavity (except the 93rd) is powered by a 550 kW pulsed klystron. Issues addressed include choice of peak surface gradient, optimization of cavity shape, selection of a scaled KEK input power coupler, selection of scaled TESLA higher mode couplers, and control of the effects of higher order modes on the beam. (author)

Smart Rack Monitor for the Linac control system

International Nuclear Information System (INIS)

Shtirbu, S.; Goodwin, R.W.; McCrory, E.S.; Shea, M.F.

1991-01-01

The Smart Rack Monitor (SRM) is a low-cost, one board, data-acquisition module for the upgraded Linac control system at Fermilab. The SRM is based on the Motorola MC68332 microcontroller in the Business Card Computer (BCC) configuration. It is connected to the Linac local control station (to be referred to as Local Station) by an Arcnet LAN, and can be located close to the controlled hardware. Each Local Station is connected to several SRMs. The SRM has 64 A-D channels, sixteen D-A channels, and eight bytes of digital I/O on the mother board. Software Components Group's pSOS is the SRM's kernel. The SRM's software is cross-developed on VAX/VMS in C. The SRM does not have an attached console and is fully controlled by the Local Station. It performs data acquisition and settings, as directed by the Local Station. Its existence is transparent to the rest of the control system. The SRM supports code updates downloading from the VAX, through the Local Station

SOVENT BASED ENHANCED OIL RECOVERY FOR IN-SITU UPGRADING OF HEAVY OIL SANDS

Energy Technology Data Exchange (ETDEWEB)

Munroe, Norman

2009-01-30

With the depletion of conventional crude oil reserves in the world, heavy oil and bitumen resources have great potential to meet the future demand for petroleum products. However, oil recovery from heavy oil and bitumen reservoirs is much more difficult than that from conventional oil reservoirs. This is mainly because heavy oil or bitumen is partially or completely immobile under reservoir conditions due to its extremely high viscosity, which creates special production challenges. In order to overcome these challenges significant efforts were devoted by Applied Research Center (ARC) at Florida International University and The Center for Energy Economics (CEE) at the University of Texas. A simplified model was developed to assess the density of the upgraded crude depending on the ratio of solvent mass to crude oil mass, temperature, pressure and the properties of the crude oil. The simplified model incorporated the interaction dynamics into a homogeneous, porous heavy oil reservoir to simulate the dispersion and concentration of injected CO2. The model also incorporated the characteristic of a highly varying CO2 density near the critical point. Since the major challenge in heavy oil recovery is its high viscosity, most researchers have focused their investigations on this parameter in the laboratory as well as in the field resulting in disparaging results. This was attributed to oil being a complex poly-disperse blend of light and heavy paraffins, aromatics, resins and asphaltenes, which have diverse behaviors at reservoir temperature and pressures. The situation is exacerbated by a dearth of experimental data on gas diffusion coefficients in heavy oils due to the tedious nature of diffusivity measurements. Ultimately, the viscosity and thus oil recovery is regulated by pressure and its effect on the diffusion coefficient and oil swelling factors. The generation of a new phase within the crude and the differences in mobility between the new crude matrix and the

Optimization of the beam extraction systems for the Linac4 H{sup −} ion source

Energy Technology Data Exchange (ETDEWEB)

Fink, D. A.; Lettry, J.; Scrivens, R.; Steyaert, D. [CERN, 1211 Geneva 23 (Switzerland); Midttun, Ø. [University of Oslo, P.O. Box 1048, 0316 Oslo (Norway); CERN, 1211 Geneva 23 (Switzerland); Valerio-Lizarraga, C. A. [Departamento de Investigación en Fisica, Universidad de Sonora, Hermosillo (Mexico); CERN, 1211 Geneva 23 (Switzerland)

2015-04-08

The development of the Linac 4 and its integration into CERN’s acceleration complex is part of the foreseen luminosity upgrade of the Large Hadron Collider (LHC). The goal is to inject a 160 MeV H{sup −} beam into the CERN PS Booster (PSB) in order to increase the beam brightness by a factor of 2 compared to the 50 MeV proton linac, Linac 2, that is currently in operation. The requirements for the ion source are a 45 keV H{sup −} beam of 80 mA intensity, 2 Hz repetition rate and 0.5 ms pulse length within a normalized rms-emittance of 0.25 mm· mrad. The previously installed beam extraction system has been designed for an H{sup −} ion beam intensity of 20 mA produced by an RF-volume source with an electron to H{sup −} ratio of up to 50. For the required intensity upgrades of the Linac4 ion source, a new beam extraction system is being produced and tested; it is optimized for a cesiated surface RF-source with a nominal beam current of 40 mA and an electron to H{sup −} ratio of 4. The simulations, based on the IBSIMU code, are presented. At the Brookhaven National Laboratory (BNL), a peak beam current of more than 100 mA was demonstrated with a magnetron H{sup −} source at an energy of 35 keV and a repetition rate of 2 Hz. A new extraction system is required to operate at an energy of 45 keV; simulation of a two stage extraction system dedicated to the magnetron is presented.

Induction linacs

International Nuclear Information System (INIS)

Keefe, D.

1986-07-01

The principle of linear induction acceleration is described, and examples are given of practical configurations for induction linacs. These examples include the Advanced Technology Accelerator, Long Pulse Induction Linac, Radial Line Accelerator (RADLAC), and Magnetically-Insulated Electron-Focussed Ion Linac. A related concept, the auto accelerator, is described in which the high-current electron-beam technology in the sub-10 MeV region is exploited to produce electron beams at energies perhaps as high as the 100 to 1000 MeV range. Induction linacs for ions are also discussed. The efficiency of induction linear acceleration is analyzed

Production of Medical Isotopes with Electron Linacs

Energy Technology Data Exchange (ETDEWEB)

Rotsch, D A; Alford, K.; Bailey, J. L.; Bowers, D. L.; Brossard, T.; Brown, M. A.; Chemerisov, S. D.; Ehst, D.; Greene, J.; Gromov, R. G.; Grudzinski, J.J.; Hafenrichter, L.; Hebden, A. S.; Henning, W.; Heltemes, T. A.; Jerden, J.; Jonah, C. D.; Kalensky, M.; Krebs, J. F.; Makarashvili, V.; Micklich, B.; Nolen, J.; Quigley, K. J.; Schneider, J. F.; Smith, N. A.; Stepinski, D. C.; Sun, Z.; Tkac, P.; Vandegrift, G. F.; Virgo, M J; Wesolowski, K. A.; Youker, A. J.

2017-06-01

Radioisotopes play important roles in numerous areas ranging from medical treatments to national security and basic research. Radionuclide production technology for medical applications has been pursued since the early 1900s both commercially and in nuclear science centers. Many medical isotopes are now in routine production and are used in day-to-day medical procedures. Despite these advancements, research is accelerating around the world to improve the existing production methodologies as well as to develop novel radionuclides for new medical appli-cations. Electron linear accelerators (linacs) represent a unique method for the production of radioisotopes. Even though the basic technology has been around for decades, only recently have electron linacs capable of producing photons with sufficient energy and flux for radioisotope production become available. Housed in Argonne Nation-al Laboratory’s Low Energy Accelerator Facility (LEAF) is a newly upgraded 55 MeV/25-kW electron linear ac-celerator, capable of producing a wide range of radioiso-topes. This talk will focus on the work being performed for the production of the medical isotopes 99Mo (99Mo/99mTc generator), 67Cu, and 47Sc.

Present status and future directions of the JAERI superconducting RF linac-based FEL

International Nuclear Information System (INIS)

Minehara, EJ.; Yamauchi, T.; Sugimori, M.; Sawamura, M.; Hajima, R.; Nagai, R.; Kikuzawa, N.; Nishimori, N.; Shizuma, T.

2000-01-01

The JAERI superconducting rf linac based FEL has successfully been lased to produce a 2.34kW FEL light and l00kW electron beam output in quasi continuous wave operation in February 2000. Twice larger output than the present program goal of 1kW was achieved to improve the optical out coupling method in the FEL optical resonator, the electron gun, and the electron beam optics in the JAERI FEL driver. As our next 2 years program goal is the 100kW class FEL light and a few MW class electron beam output in average, quasi continuous wave operation of the light and electron beam will be planned in the JAERI superconducting rf linac based FEL facility. Conceptual and engineering design options needed for such a very high power operation will be discussed to improve and to upgrade the existing facility. Finally, several applications, table-top superconducting rf linac based FELs, and an X-ray FEL R and D will be discussed as a next-five years program at JAERI-FEL laboratory. (author)

The SSRL linacs for injection to the storage ring and rf gun testing

International Nuclear Information System (INIS)

Park, Sanghyun; Weaver, James N.

1996-01-01

The Stanford Synchrotron Radiation Laboratory (SSRL) operates two linac systems. One has three SLAC type linac sections powered by two klystrons for injection of electrons at 120 MeV into the booster ring, boosting the energy to 2.3 GeV to fill the SPEAR. After the ramping, the SPEAR stores up to 100 mA of the beam at 3.0 GeV. The preinjector consists of a thermionic RF gun, an alpha magnet, and a chopper along with focusing magnets. The other has one 10 foot section powered by the injector klystron for the testing of RF gun with photocathode, which is driven by a separate klystron. This paper describes present systems with their operational parameters, followed by plans for the upgrades and RF gun development efforts at the SSRL. (author)

Linac-beam characterizations at 600 MeV using optical transition radiation diagnostics.

Energy Technology Data Exchange (ETDEWEB)

Lumpkin, A. H.

1998-05-27

Selected optical diagnostics stations were upgraded in anticipation of low-emittance, bright electron beams from a thermionic rf gun or a photoelectric rf gun on the Advanced Photon Source (APS) injector linac. These upgrades include installation of optical transition radiation (OTR) screens, transport lines, and cameras for use in transverse beam size measurements and longitudinal profile measurements. Using beam from the standard thermionic gun, tests were done at 50 MeV and 400 to 650 MeV. Data were obtained on the limiting spatial ({sigma} {approximately} 200 {micro}m) and temporal resolution (300 ms) of the Chromox (Al{sub 2}O{sub 3} : Cr) screen (250-{micro}n thick) in comparison to the OTR screens. Both charge-coupled device (CCD) and charge-injection device (CID) video cameras were used as well as the Hamamatsu C5680 synchroscan streak camera operating at a vertical deflection rate of 119.0 MHz (the 24th subharmonic of the S-band 2856-MHz frequency). Beam transverse sizes as small as {sigma}{sub x} = 60 {micro}m for a 600-MeV beam and micropulse bunch lengths of {sigma}{sub {tau}}<3 ps have been recorded for macropulse-averaged behavior with charges of about 2 to 3 nC per macropulse. These techniques are applicable to linac-driven, fourth-generation light source R and D experiments including the APS's SASE FEL experiment.

Proton Beam Intensity Upgrades for the Neutrino Program at Fermilab

Energy Technology Data Exchange (ETDEWEB)

Bhat, C. M. [Fermilab

2016-12-15

Fermilab is committed to upgrading its accelerator complex towards the intensity frontier to pursue HEP research in the neutrino sector and beyond. The upgrade has two steps: 1) the Proton Improvement Plan (PIP), which is underway, has its primary goal to start providing 700 kW beam power on NOvA target by the end of 2017 and 2) the foreseen PIP–II will replace the existing LINAC, a 400 MeV injector to the Booster, by an 800 MeV superconducting LINAC by the middle of next decade, with output beam intensity from the Booster increased significantly and the beam power on the NOvA target increased to <1.2 MW. In any case, the Fermilab Booster is going to play a very significant role for the next two decades. In this context, we have recently developed and commissioned an innovative beam injection scheme for the Booster called "early injection scheme". This scheme is already in operation and has a potential to increase the Booster beam intensity from the PIP design goal by a considerable amount with a reduced beam emittance and beam loss. In this paper, we will present results from our experience from the new scheme in operation, current status and future plans.

LINAC5 - A Quasi-Alvarez Linac for BioLEIR

International Nuclear Information System (INIS)

Garland, J M; Lallement, J-B; Lombardi, A

2017-01-01

LINAC5 is a new linac proposed for the acceleration of light ions with Q/A = 1/3 to 1/4 for medical applications within the BioLEIR (Low Energy Ion Ring) design study at CERN. We propose a novel quasi-Alvarez drift-tube linac (DTL) accelerating structure design for LINAC5, which can reduce the length of a more conventional DTL structure, yet allows better beam focussing control and flexibility than the inter-digital H (IH) structures typically used for modern ion acceleration. We present the main sections of the linac with total length ∼12 m, including a 202 MHz radio frequency quadrupole (RFQ) a matching medium energy beam transport (MEBT) and a 405 MHz quasi-Alvarez accelerating section with an output energy of 4.2 MeV/u. Permanent magnet quadrupoles are proposed for use in the quasi-Alvarez structure to improve the compactness of the design and increase the efficiency. Lattice design considerations, multi-particle beam dynamics simulations and RFQ and radio frequency (RF) cavity designs are presented. (paper)

Superconducting linac

International Nuclear Information System (INIS)

Bollinger, L.M.; Shepard, K.W.; Wangler, T.P.

1978-01-01

This project has two goals: to design, build, and test a small superconducting linac to serve as an energy booster for heavy ions from an FN tandem electrostatic accelerator, and to investigate various aspects of superconducting rf technology. The main design features of the booster are described, a status report on various components (resonators, rf control system, linac control system, cryostats, buncher) is given, and plans for the near future are outlined. Investigations of superconducting-linac technology concern studies on materials and fabrication techniques, resonator diagnostic techniques, rf-phase control, beam dynamics computer programs, asymmetry in accelerating field, and surface-treatment techniques. The overall layout of the to-be-proposed ATLAS, the Argonne Tandem-Linac Accelerator System, is shown; the ATLAS would use superconducting technology to produce beams of 5 to 25 MeV/A. 6 figures

New halo formation mechanism at the KEK compact energy recovery linac

Science.gov (United States)

Tanaka, Olga; Nakamura, Norio; Shimada, Miho; Miyajima, Tsukasa; Ueda, Akira; Obina, Takashi; Takai, Ryota

2018-02-01

The beam halo mitigation is a very important challenge for reliable and safe operation of a high-energy machine. A systematic beam halo study was conducted at the KEK compact energy recovery linac (cERL) since non-negligible beam loss was observed in the recirculation loop during a common operation. We found that the beam loss can be avoided by making use of the collimation system. Beam halo measurements have demonstrated the presence of vertical beam halos at multiple locations in the beam line (except the region near the electron gun). Based on these observations, we made a conjecture that the transverse beam halo is attributed to the longitudinal bunch tail arising at the photocathode. The transfer of particles from the longitudinal space to a transverse halo may have been observed and studied in other machines, considering nonlinear effects as their causes. However, our study demonstrates a new unique halo formation mechanism, in which a transverse beam halo can be generated by a longitudinal bunch tail due to transverse rf kicks from the accelerating (monopole) fields of the radio-frequency cavities. This halo formation occurs when nonrelativistic particles enter the cavities with a transverse offset, even if neither nonlinear optics nor nonlinear beam effects are present. A careful realignment of the injector system will mitigate the present halo. Another possible cure is to reduce the bunch tails by changing the photocathode material from the present GaAs to a multi-alkali that is known to have a shorter longitudinal tail.

Overview of the CERN Linac4 beam instrumentation

CERN Document Server

Roncarolo, F; Bravin, E; Dehning, B; Duraffourg, M; Gerard, D; Holzer, E B; Lenardon, F; Focker, G; Raich, U; Soby, L; Sordet, M; Tan, J; Tranquille, G; Vuitton, C; Zamantzas, C; Cheymol, B

2010-01-01

The CERN LINAC4 will represent the first upgrade of the LHC injection chain, by accelerating H- ions from 45 KeV to 160 MeV for charge-exchange injection into the PS Booster. In order to provide its safe and efficient commissioning and operation, a wide variety of beam diagnostics devices has been designed for installation at convenient locations all over the accelerator length and in the transfer line to the PS Booster. This paper gives an overview of all instrumentation devices, including those to measure beam position, transverse and longitudinal profile, beam current and beam loss. The well advanced status of the system design and the main instrument features are discussed

Prompt radiation, shielding and induced radioactivity in a high-power 160 MeV proton linac

Energy Technology Data Exchange (ETDEWEB)

Magistris, Matteo [CERN, CH-1211 Geneva 23 (Switzerland)]. E-mail: matteo.magistris@cern.ch; Silari, Marco [CERN, CH-1211 Geneva 23 (Switzerland)

2006-06-23

CERN is designing a 160 MeV proton linear accelerator, both for a future intensity upgrade of the LHC and as a possible first stage of a 2.2 GeV superconducting proton linac. A first estimate of the required shielding was obtained by means of a simple analytical model. The source terms and the attenuation lengths used in the present study were calculated with the Monte Carlo cascade code FLUKA. Detailed FLUKA simulations were performed to investigate the contribution of neutron skyshine and backscattering to the expected dose rate in the areas around the linac tunnel. An estimate of the induced radioactivity in the magnets, vacuum chamber, the cooling system and the concrete shield was performed. A preliminary thermal study of the beam dump is also discussed.

Present and next steps of the JAERI superconducting rf linac based FEL program

International Nuclear Information System (INIS)

Minehara, E.J.; Yamauchi, T.; Sugimoto, M.

2000-01-01

The JAERI superconducting rf linac based FEL has successfully been lased to produce a 0.3 kW FEL light and 100 kW or larger electron beam output in quasi continuous wave operation in 1999. The 1 kW class output as our present program goal will be achieved to improve the optical out coupling method in the FEL optical resonator, the electron gun, and the electron beam optics in the JAERI FEL driver. As our next 5 year program goal is the 100 kW class FEL light and a few tens MW class electron beam output in average, quasi continuous wave operation of the light and electron beam will be planned in the JAERI superconducting rf linac based FEL facility. Conceptual design options needed for such a very high power operation and shorter wavelength light sources will be discussed to improve and to upgrade the exciting facility. (author)

Conceptual design of the SPL II A high-power superconducting $H^-$ linac at CERN

CERN Document Server

Baylac, M; Benedico-Mora, E; Caspers, Friedhelm; Chel, S; Deconto, J M; Duperrier, R; Froidefond, E; Garoby, R; Hanke, K; Hill, C; Hori, M; Inigo-Golfin, J; Kahle, K; Kroyer, T; Küchler, D; Lallement, J B; Lindroos, M; Lombardi, A M; López Hernández, A; Magistris, M; Meinschad, T; Millich, Antonio; Noah-Messomo, E; Pagani, C; Palladino, V; Paoluzzi, M; Pasini, M; Pierini, P; Rossi, C; Royer, J P; Sanmartí, M; Sargsyan, E; Scrivens, R; Silari, M; Steiner, T; Tückmantel, Joachim; Uriot, D; Vretenar, M

2006-01-01

An analysis of the revised physics needs and recent progress in the technology of superconducting RF cavities have led to major changes in the speci cation and in the design for a Superconducting Proton Linac (SPL) at CERN. Compared with the rst conceptual design report (CERN 2000–012) the beam energy is almost doubled (3.5 GeV instead of 2.2 GeV), while the length of the linac is reduced by 40% and the repetition rate is reduced to 50 Hz. The basic beam power is at a level of 4–5MW and the approach chosen offers enough margins for upgrades. With this high beam power, the SPL can be the proton driver for an ISOL-type radioactive ion beam facility of the next generation (`EURISOL'), and for a neutrino facility based on superbeam C beta-beam or on muon decay in a storage ring (`neutrino factory'). The SPL can also replace the Linac2 and PS Booster in the low-energy part of the CERN proton accelerator complex, improving signi cantly the beam performance in terms of brightness and intensity for the bene t of al...

High-beta linac structures

International Nuclear Information System (INIS)

Schriber, S.O.

1979-01-01

Accelerating structures for high-beta linacs that have been and are in use are reviewed in terms of their performance. Particular emphasis is given to room-temperature structures and the disk-and-washer structure. The disk-and-washer structure has many attractive features that are discussed for pulsed high-gradient linacs, for 100% duty-cycle medium-gradient linacs and for high-current linacs requiring maximal amounts of stored energy in the electric fields available to the beam

Investigation of thermal integration between biogas production and upgrading

International Nuclear Information System (INIS)

Zhang, Xiaojing; Yan, Jinying; Li, Hailong; Chekani, Shabnam; Liu, Loncheng

2015-01-01

Highlights: • Identify thermal characteristics of amine-based biogas upgrading for waste heat recovery. • Identify thermal characteristics of AD biogas production as sink for heat recovery. • Evaluation of thermal integration between biogas production and upgrading to improve overall energy efficiency. • Cost analysis applied for the economic feasibility of the thermal integration. • Using the principles of target design and system integration for connected thermal processes. - Abstract: Thermal integration of anaerobic digestion (AD) biogas production with amine-based chemical absorption biogas upgrading has been studied to improve the overall efficiency of the intergraded system. The thermal characteristics have been investigated for industrial AD raw biogas production and amine-based chemical absorption biogas upgrading. The investigation provides a basic understanding for the possibilities of energy saving through thermal integration. The thermal integration is carried out through well-defined cases based on the thermal characteristics of the biogas production and the biogas upgrading. The following factors are taken into account in the case study: thermal conditions of sub-systems, material and energy balances, cost issues and main benefits. The potential of heat recovery has been evaluated to utilise the waste heat from amine-based upgrading process for the use in the AD biogas production. The results show that the thermal integration has positive effects on improving the overall energy efficiency of the integrated biogas plant. Cost analysis shows that the thermal integration is economically feasible

Linac 1, inner structure

CERN Multimedia

1968-01-01

This photo shows the inner structure of Linac 1. As injector to the PS, and later to the Booster, Linac 1 accelerated protons to 50 MeV, but it has also accelerated heavier ions. Fitted with a 520 keV RFQ pre-injector (instead of the original Cockcroft-Walton generator), it delivered protons and heavy ions to LEAR, from 1982 to 1992. After 33 years of faithful service, Linac 1 was dismantled in 1992 to make room for Linac 3 (Pb ions).

Linac4 H− ion sources

International Nuclear Information System (INIS)

Lettry, J.; Aguglia, D.; Andersson, P.; Bertolo, S.; Butterworth, A.; Coutron, Y.; Dallocchio, A.; David, N.; Chaudet, E.; Fink, D. A.; Garlasche, M.; Grudiev, A.; Guida, R.; Hansen, J.; Haase, M.; Jones, A.; Koszar, I.; Lallement, J.-B.; Lombardi, A. M.; Machado, C.

2016-01-01

CERN’s 160 MeV H − linear accelerator (Linac4) is a key constituent of the injector chain upgrade of the Large Hadron Collider that is being installed and commissioned. A cesiated surface ion source prototype is being tested and has delivered a beam intensity of 45 mA within an emittance of 0.3 π ⋅ mm ⋅ mrad. The optimum ratio of the co-extracted electron- to ion-current is below 1 and the best production efficiency, defined as the ratio of the beam current to the 2 MHz RF-power transmitted to the plasma, reached 1.1 mA/kW. The H − source prototype and the first tests of the new ion source optics, electron-dump, and front end developed to minimize the beam emittance are presented. A temperature regulated magnetron H − source developed by the Brookhaven National Laboratory was built at CERN. The first tests of the magnetron operated at 0.8 Hz repetition rate are described

Design for a 1.3 MW, 13 MeV Beam Dump for an Energy Recovery Linac

CERN Document Server

Sinclair, Charles K; Smith, Colin H

2005-01-01

The electron beam exiting an Energy Recovery Linac (ERL) is dumped close to the injection energy. This energy is chosen as low as possible while allowing the beam quality specifications to be met. As ERLs are designed for high average beam current, beam dumps are required to handle high beam power at low energy. Low energy electrons have a short range in practical dump materials, requiring the beam size at the dump face be enlarged to give acceptable power densities and heat fluxes. Cornell University is developing a 100 mA average current ERL as a synchrotron radiation source. The 13 MeV optimum injection energy requires a 1.3 MW beam dump. We present a mature design for this dump, using an array of water-cooled extruded copper tubes. This array is mounted in the accelerator vacuum normal to the beam. Fatigue failure resulting from abrupt thermal cycles associated with beam trips is a potential failure mechanism. We report on designs for a 75 kW, 750 keV tube-cooled beryllium plate dump for electron gun test...

Drift tubes of Linac 2

CERN Multimedia

CERN PhotoLab

1977-01-01

With the advent of the 800 MeV PS Booster in 1972, the original injector of the PS, a 50 MeV Alvarez-type proton linac, had reached its limits, in terms of intensity and stability. In 1973 one therefore decided to build a new linac (Linac 2), also with a drift-tube Alvarez structure and an energy of 50 MeV. It had a new Cockcroft-Walton preinjector with 750 keV, instead of the previous one with 500 keV. Linac 2 was put into service in 1980. The old Linac 1 was then used for the study of, and later operation with, various types of ions. This picture shows Linac 2 drift-tubes, suspended on stems coming from the top, in contrast to Linac 1, where the drift-tubes stood on stems coming from the bottom.

New high power 200 MHz RF system for the LANSCE drift tube linac

International Nuclear Information System (INIS)

Lyles, J.; Friedrichs, C.; Lynch, M.

1998-01-01

The Los Alamos Neutron Science Center (LANSCE) linac provides an 800 MeV direct H + proton beam, and injects H - to the upgraded proton storage ring for charge accumulation for the Short Pulse Spallation Source. Accelerating these interlaced beams requires high average power from the 201.25 MHz drift tube linac (DTL) RF system. Three power amplifiers have operated at up to three Megawatts with 12% duty factor. The total number of electron power tubes in the RF amplifiers and their modulators has been reduced from fifty-two to twenty-four. The plant continues to utilize the original design of a tetrode driving a super power triode. Further increases in the linac duty factor are limited, in part, by the maximum dissipation ratings of the triodes. A description of the system modifications proposed to overcome these limitations includes new power amplifiers using low-level RF modulation for tank field control. The first high power Diacrode reg-sign is being delivered and a new amplifier cavity is being designed. With only eight power tubes, the new system will deliver both peak power and high duty factor, with lower mains power and cooling requirements. The remaining components needed for the new RF system will be discussed

Compendium of Scientific Linacs

Energy Technology Data Exchange (ETDEWEB)

Clendenin, James E

2003-05-16

The International Committee supported the proposal of the Chairman of the XVIII International Linac Conference to issue a new Compendium of linear accelerators. The last one was published in 1976. The Local Organizing Committee of Linac96 decided to set up a sub-committee for this purpose. Contrary to the catalogues of the High Energy Accelerators which compile accelerators with energies above 1 GeV, we have not defined a specific limit in energy. Microtrons and cyclotrons are not in this compendium. Also data from thousands of medical and industrial linacs has not been collected. Therefore, only scientific linacs are listed in the present compendium. Each linac found in this research and involved in a physics context was considered. It could be used, for example, either as an injector for high energy accelerators, or in nuclear physics, materials physics, free electron lasers or synchrotron light machines. Linear accelerators are developed in three continents only: America, Asia, and Europe. This geographical distribution is kept as a basis. The compendium contains the parameters and status of scientific linacs. Most of these linacs are operational. However, many facilities under construction or design studies are also included. A special mention has been made at the end for the studies of future linear colliders.

Superconducting heavy-ion linacs

International Nuclear Information System (INIS)

Bollinger, L.M.

1977-01-01

A summary is given of plans developed by four different groups for the construction of small superconducting linacs to boost the energy of heavy ions from existing tandem electrostatic accelerators. The projects considered are the linac under construction at Argonne and the design efforts at Karlsruhe, at Stanford, and by a Cal Tech-Stony Brook collaboration. The intended uses of the accelerator systems are stated. Beam dynamics of linacs formed of short independently-phased resonators are reviewed, and the implications for performance are discussed. The main parameters of the four linacs are compared, and a brief analysis of accelerating structures is given

Superconducting linac booster

International Nuclear Information System (INIS)

Srinivasan, B.; Betigeri, M.G.; Pandey, M.K.; Pillay, R.G.; Kurup, M.B.

1997-01-01

The report on superconducting LINAC booster, which is a joint project of Bhabha Atomic Research Centre (BARC) and Tata Institute of Fundamental Research (TIFR), brings out the work accomplished so far towards the development of the technology of superconducting LINAC to boost the energy of ions from the 14UD Pelletron. The LINAC is modular in construction with each module comprising of a helium cryostat housing four lead-plated quarter wave resonators. The resonators are superconducting for temperatures below 7.19K. An energy boost of 2 MeV/q per module is expected to be achieved. The first module and the post-tandem superbuncher have been fabricated and tested on the LINAC beam line. This report gives a summary of the technological achievements and also brings out the difficulties encountered during the R and D phase. (author)

DOE Hanford Network Upgrades and Disaster Recovery Exercise Support the Cleanup Mission Now and into the Future

Energy Technology Data Exchange (ETDEWEB)

Eckman, Todd J.; Hertzel, Ali K.; Lane, James J.

2013-11-07

In 2013, the U.S. Department of Energy's (DOE) Hanford Site, located in Washington State, funded an update to the critical network infrastructure supporting the Hanford Federal Cloud (HFC). The project, called ET-50, was the final step in a plan that was initiated five years ago called "Hanford's IT Vision, 2015 and Beyond." The ET-50 project upgraded Hanford's core data center switches and routers along with a majority of the distribution layer switches. The upgrades allowed HFC the network intelligence to provide Hanford with a more reliable and resilient network architecture. The culmination of the five year plan improved network intelligence and high performance computing as well as helped to provide 10 Gbps capable links between core backbone devices (10 times the previous bandwidth). These improvements allow Hanford the ability to further support bandwidth intense applications, such as video teleconferencing. The ET-50 switch upgrade, along with other upgrades implemented from the five year plan, have prepared Hanford's network for the next evolution of technology in voice, video, and data. Hand-in-hand with ET-50's major data center outage, Mission Support Alliance's (MSA) Information Management (IM) organization executed a disaster recovery (DR) exercise to perform a true integration test and capability study. The DR scope was planned within the constraints of ET-50's 14 hour datacenter outage window. This DR exercise tested Hanford's Continuity of Operations (COOP) capability and failover plans for safety and business critical Hanford Federal Cloud applications. The planned suite of services to be tested was identified prior to the outage and plans were prepared to test the services ability to failover from the primary Hanford data center to the backup data center. The services tested were: Core Network (backbone, firewall, load balancers); Voicemail; Voice over IP (VoIP); Emergency Notification; Virtual desktops

DOE Hanford Network Upgrades and Disaster Recovery Exercise Support the Cleanup Mission Now and into the Future

International Nuclear Information System (INIS)

Eckman, Todd J.; Hertzel, Ali K.; Lane, James J.

2013-01-01

In 2013, the U.S. Department of Energy's (DOE) Hanford Site, located in Washington State, funded an update to the critical network infrastructure supporting the Hanford Federal Cloud (HFC). The project, called ET-50, was the final step in a plan that was initiated five years ago called 'Hanford's IT Vision, 2015 and Beyond.' The ET-50 project upgraded Hanford's core data center switches and routers along with a majority of the distribution layer switches. The upgrades allowed HFC the network intelligence to provide Hanford with a more reliable and resilient network architecture. The culmination of the five year plan improved network intelligence and high performance computing as well as helped to provide 10 Gbps capable links between core backbone devices (10 times the previous bandwidth). These improvements allow Hanford the ability to further support bandwidth intense applications, such as video teleconferencing. The ET-50 switch upgrade, along with other upgrades implemented from the five year plan, have prepared Hanford's network for the next evolution of technology in voice, video, and data. Hand-in-hand with ET-50's major data center outage, Mission Support Alliance's (MSA) Information Management (IM) organization executed a disaster recovery (DR) exercise to perform a true integration test and capability study. The DR scope was planned within the constraints of ET-50's 14 hour datacenter outage window. This DR exercise tested Hanford's Continuity of Operations (COOP) capability and failover plans for safety and business critical Hanford Federal Cloud applications. The planned suite of services to be tested was identified prior to the outage and plans were prepared to test the services ability to failover from the primary Hanford data center to the backup data center. The services tested were: Core Network (backbone, firewall, load balancers); Voicemail; Voice over IP (VoIP); Emergency Notification; Virtual desktops; and, Select set of production applications

Experimental studies of 7-cell dual axis asymmetric cavity for energy recovery linac

Directory of Open Access Journals (Sweden)

I. V. Konoplev

2017-10-01

Full Text Available High average current, transportable energy recovery linacs (ERLs can be very attractive tools for a number of applications including next generation high-luminosity, compact light sources. Conventional ERLs are based on an electron beam circulating through the same set of rf cavity cells. This leads to an accumulation of high-order modes inside the cavity cells, resulting in the development of a beam breakup (BBU instability, unless the beam current is kept below the BBU start current. This limits the maximum current which can be transported through the ERL and hence the intensity of the photon beam generated. It has recently been proposed that splitting the accelerating and decelerating stages, tuning them separately and coupling them via a resonance coupler can increase the BBU start current. The paper presents the first experimental rf studies of a dual axis 7-cell asymmetric cavity and confirms the properties predicted by the theoretical model. The field structures of the symmetric and asymmetric modes are measured and good agreement with the numerical predictions is demonstrated. The operating mode field flatness was also measured and discussed. A novel approach based on the coupled mode (Fano-like model has been developed for the description of the cavity eigenmode spectrum and good agreement between analytical theory, numerical predictions and experimental data is shown. Numerical and experimental results observed are analyzed, discussed and a good agreement between theory and experiment is demonstrated.

The JLab 12 GeV Energy Upgrade of CEBAF for QCD and Hadronic Physics

International Nuclear Information System (INIS)

Lawrence Cardman; Leigh Harwood

2007-01-01

CEBAF at Jefferson Lab is a 5-pass, recirculating cw electron linac operating at ∼6 GeV and devoted to basic research in nuclear physics. The 12 GeV Upgrade is a major project, sponsored by the DOE Office of Nuclear Physics, that will expand its research capabilities substantially by doubling the maximum energy and adding major new experimental apparatus. We anticipate that the project will receive Critical Decision 2 approval this year and begin construction in 2008. The research program motivating the Upgrade includes: the study of hybrid mesons, which involve excited states of the glue, to explore the nature of quark confinement; dramatic improvements in our understanding of the QCD structure of the hadrons through the extension of our knowledge of their parton distribution functions to high xBjorken, where they are dominated by underlying valence quark structure, and a program of nucleon ''tomography'' via measurements of the Generalized Parton Distributions (GPDs), a broad program of experiments in the physics of nuclei that aims to understand the QCD basis for the nucleon-nucleon force and how nucleons and mesons arise as an approximation to the underlying quark-gluon structure; and precision tests of the Standard Model through parity violating deep inelastic and Moeller scattering. The Upgrade includes: doubling the accelerating voltages of the linacs by adding 10 new high-performance cryomodules; the requisite expansion of the 2K cryogenics plant and rf power systems to support these cryomodules; upgrading the beam transport system from 6 to 12 GeV through extensive re-use and/or modification of existing hardware; and the addition of one recirculation arc, a new experimental area, and the beamline to it; and the construction of major new experimental equipment for the GPD, high-xBjorken, and hybrid meson programs. The presentation will describe the science briefly and provide some details about the accelerator plans

Construction of SPring-8 LINAC

International Nuclear Information System (INIS)

Yokomizo, Hideaki; Yoshikawa, Hiroshi; Suzuki, Shinsuke; Yanagida, Ken-ichi; Mizuno, Akihiko; Hori, Toshihiko; Tamezane, Kenji; Kodera, Masahiko; Sakaki, Hironao; Mashiko, Katsuo

1993-01-01

Construction of the linac building has been started in February 1993. The components of the linac are under manufacturing. The preinjector of linac was already constructed and temporarily installed in Tokai Establishment in order to test the beam quality. (author)

Upgrade of High-Energy X-Ray real-time radioscopy for KROTOS experiment

Energy Technology Data Exchange (ETDEWEB)

Estre, N.; Payan, E.; Cassiaut-Louis, N.; Compagnon, F.; Valerian, M.; Mallet, R. [CEA-Cadarache (France)

2015-07-01

As part of its R and D programs on severe accidents, in particular on understanding of corium-water interaction, CEA is commissioning an update of the KROTOS experiment at Cadarache. The Xray imaging setup (high energy real-time radioscopy) is upgraded to provide the best performances for the new experimental program. In order to fit the performance needs (faster acquisition, smaller detection limit and higher field of view), two radioscopy setups, with two linear accelerators (linacs 9 MV and 6 MV), are placed in the irradiation cell. Having discussed the expected performances in terms of frequency, detection limit and field-of-view, this article details each stage of both radioscopy chains: principles and technical characteristics. Then, linacs and cameras synchronization (at few hundred Hertz), data flows and storage setups are detailed. Finally, experimental characterizations and performance validations on phantom are presented. (authors)

Upgrade of High-Energy X-Ray real-time radioscopy for KROTOS experiment

International Nuclear Information System (INIS)

Estre, N.; Payan, E.; Cassiaut-Louis, N.; Compagnon, F.; Valerian, M.; Mallet, R.

2015-01-01

As part of its R and D programs on severe accidents, in particular on understanding of corium-water interaction, CEA is commissioning an update of the KROTOS experiment at Cadarache. The Xray imaging setup (high energy real-time radioscopy) is upgraded to provide the best performances for the new experimental program. In order to fit the performance needs (faster acquisition, smaller detection limit and higher field of view), two radioscopy setups, with two linear accelerators (linacs 9 MV and 6 MV), are placed in the irradiation cell. Having discussed the expected performances in terms of frequency, detection limit and field-of-view, this article details each stage of both radioscopy chains: principles and technical characteristics. Then, linacs and cameras synchronization (at few hundred Hertz), data flows and storage setups are detailed. Finally, experimental characterizations and performance validations on phantom are presented. (authors)

Linac pre-injector

CERN Multimedia

CERN PhotoLab

1965-01-01

New accelerating column of the linac pre-injector, supporting frame and pumping system. This new system uses two mercury diffusion pumps (in the centre) and forms part of the modifications intended to increase the intensity of the linac. View taken during assembly in the workshop.

Progress Report on SIMULINK Modelling of RF Cavity Control for SPL Extension to LINAC4 Theory and Analysis behind Simulation Results of SPL Model Using I/Q Components in SIMULINK to Date, Including Lorentz Force Effects and Multiple Cavities Driven by Single Feedback Loop

CERN Document Server

Hernandez, M

2011-01-01

In the context of a luminosity upgrade for the LHC within the coming years, works have started on LINAC4 to provide an infrastructure for updating the LHC supplier chain. In order to achieve energy levels and particles per bunch necessary for the expected rate of events at LHC detectors and related experiments, a project proposal is underway for an appended Superconducting Proton LINAC (SPL) that will run from the normal conducting LINAC4 and LP-SPL onto the LHC supplier chain. Thus, the SPL will have two main functions: Firstly, to provide H- beam for injection into the PS2 which is compatible with LHC luminosity. For this purpose the SPL will accelerate the output beam of LINAC4 from 1GeV to 4GeV,removing, at the same time, the necessity for PSB operation in the LHC supply chain. Secondly, it will provide an infrastructure upgradeable to meet the needs of all potential high-power proton users at CERN (EURISOL) and possibly neutrino production facilities. For high-power applications of this nature the SPL wi...

A deuteron linac for a high-intensity neutron source

International Nuclear Information System (INIS)

Staples, J.; Clark, D.; Grunder, H.; Lancaster, H.; Main, R.; Selph, F.; Smith, L.; Voelker, F.; Yourd, R.

1976-01-01

The preliminary design of an accelerator suitable to meet the flux and neutron energy requirements of a CTR materials test facility is presented. The specifications of such a facility call for a neutron flux of 10 14 n/cm 2 -sec distributed over an area of about 10 2 cm 2 with a neutron spectrum similar to that anticipated from a fusion reactor. A 30 MeV deuteron linac producing a CW beam of 125 mA, upgradable to 40 MeV at 250 mA at a later date, would produce the relatively broad spectrum of neutrons at the required intensity. Attention to the low-energy beam intercept on the drift tubes and diffusive losses producing neutrons and attendant activation problems are discussed

Linacs for medical isotope production

International Nuclear Information System (INIS)

Pramudita, A.

2012-01-01

This paper reviews efforts on using high energy (25-30 MeV) and high power (10-20 kW) electron linacs and lower energy (7 MeV) proton linacs for medical radioisotope production. Using high energy x-rays from the electron linacs, PET (Positron Emission Tomography) radioisotopes are produced through photonuclear reactions such as 19 F(γ,n) 18 F, which also allow production of other PET radionuclides 11 C, 13 N, and 15 O. Other mostly used medical radionuclides 99m Tc can also be obtained by using the electron linacs, through photofission or photonuclear reactions. Proton linacs for PET have also been recently developed and the product has been available in the market since 2005. The linacs have been tested for 18 F production. As a proton accelerator, the target systems and nuclear reactions are similar to the ones used in PET cyclotrons. (author)

TOP LINAC design; Progetto del TOP LINAC

Energy Technology Data Exchange (ETDEWEB)

Picardi, L; Ronsivalle, C; Vignati, A [ENEA, Centro Ricerche Frascati, Rome (Italy). Dip. Innovazione

1997-11-01

The report describes a linear accelerator for protons named TOP LINAC designed for the TOP (Terapia Oncologica con Protoni, Oncological Protontherapy) project launched by the Italian National Institute of Health (Istituto Superiore di Sanita`, ISS) to explore in collaboration with the biggest Oncological Hospital in Rome (Istituto Regina Elena, IRE) the potentialities of the therapy with accelerated protons and establish guide lines for the application of this new type of radiotherapy in comparison with the more traditional electron and x-rays radiotherapy. The concept of a compact accelerator for protontherapy applications bore within the Italian Hadrontherapy Collaboration (TERA Collaboration) with the aim to diffuse the protontherapy on the National territory. The ISS program plans to use the TOP linac proton beam also for production of PET (Positron Emission Tomography) radioisotopes and radiobiology studies. Official agreements are in course between ISS and ENEA which provides its experience in the industrial and medical accelerators for the design and the construction of the TOP linac. The accelerator that will be the first 3 GHz proton linac in the world, will be composed of a 428.3 MHz 7 Me V RFQ + DTL injector followed by a 7-65 Me V section of a 3 GHz SCDTL structure and a 65 - 200 Me V variable energy SCL 3 GHz structure. In particular the SCDTL section uses a highly innovative accelerating structure patented by ENEA. In this report the clinical and physical requests are discussed and a preliminary design of the whole machine is given.

Inner structure of Linac 2

CERN Multimedia

CERN PhotoLab

1977-01-01

With the advent of the 800 MeV Booster in 1972, the original injector of the PS, a 50 MeV Alvarez-type proton linac, had reached its limits, in terms of intensity and stability. In 1973 one therefore decided to build a new linac (Linac 2), also with a drift-tube Alvarez structure and an energy of 50 MeV. It had a new Cockcroft-Walton preinjector with 750 keV, instead of the previous one with 500 keV. Linac 2 was put into service in 1980. The old Linac 1 was then used for the study of, and later operation with, various types of ions. This picture shows the inner structure of Linac 2, with drift-tubes hanging on stems under a rigid support structure, soon to be mounted inside tank 1 (750 keV to 10 MeV, the lowest-energy one of 3). Frank Malthouse is standing in the background.

ER@CEBAF: A test of 5-pass energy recovery at CEBAF

Energy Technology Data Exchange (ETDEWEB)

Bogacz, S. A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Dubbe, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hutton, A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Michalski, T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Pilat, F. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Y. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Satogata, T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Spata, M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tiefenback, M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hao, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Korysko, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-06-06

Jefferson Lab personnel have broad expertise in the design, commissioning, and operation of multiple energy recovery linacs (ERLs): the CEBAF Front-End Test (early 1990s), CEBAF-ER (2003), the IR Free Electron Laser (FEL) Demo, the IR FEL Upgrade, and the UV FEL Driver (1997-2014). Continued development of this core competency has led to this collaborative proposal to explore the forefronts of ERL technology at high energy in a unique expansion of CEBAF capability to a 5-pass ERL with negligible switchover time and programmatic impact to the CEBAF physics program. Such a capability would enable world-class studies of open issues in high-energy ERL beam dynamics that are relevant to future facilities such as electron-ion colliders (EICs). This proposal requests support from the CEBAF Program Advisory Committee to seek funding for hardware installation, and a prospective 12 days of beam time circa Fall 2018 for commissioning this high-energy multi-pass ERL experiment in CEBAF.

Design of an upgradeable 45-100 mA RFQ accelerator for FAIR

Science.gov (United States)

Zhang, Chuan; Schempp, Alwin

2009-10-01

A 325 MHz, 35 mA, 3 MeV Radio-Frequency Quadrupole (RFQ) accelerator will be operated as the first accelerating structure of the proton linac injector for the newly planned international science center Facility for Antiproton and Ion Research (FAIR) at GSI, Germany. In previous design studies, two high beam intensities, 70 and 100 mA, were used. Most recently, the design intensity has been changed to 45 mA, which is closer to the operational value. Taking advantage of the so-called New Four-Section Procedure, a new design, which is upgradable from 45 to 100 mA, has been developed for the FAIR proton RFQ. Besides the upgradability analyses, robustness studies of the new design to spatial displacements of the input beam and field errors are presented as well.

Design of an upgradeable 45-100 mA RFQ accelerator for FAIR

International Nuclear Information System (INIS)

Zhang Chuan; Schempp, Alwin

2009-01-01

A 325 MHz, 35 mA, 3 MeV Radio-Frequency Quadrupole (RFQ) accelerator will be operated as the first accelerating structure of the proton linac injector for the newly planned international science center Facility for Antiproton and Ion Research (FAIR) at GSI, Germany. In previous design studies, two high beam intensities, 70 and 100 mA, were used. Most recently, the design intensity has been changed to 45 mA, which is closer to the operational value. Taking advantage of the so-called New Four-Section Procedure, a new design, which is upgradable from 45 to 100 mA, has been developed for the FAIR proton RFQ. Besides the upgradability analyses, robustness studies of the new design to spatial displacements of the input beam and field errors are presented as well.

Commissioning of the CMS Hadron Forward Calorimeters Phase I Upgrade

CERN Document Server

Bilki, Burak

2017-01-01

The final phase of the CMS Hadron Forward Calorimeters Phase I upgrade was performed during the Extended Year End Technical Stop of 2016 and 2017. In the framework of the upgrade, the PMT boxes were reworked to implement two channel readout in order to exploit the benefits of the multi-anode PMTs in background tagging and signal recovery. The front-end electronics were also upgraded to QIE10-based electronics which implement larger dynamic range and a 6-bit TDC. Following this major upgrade, the Hadron Forward Calorimeters were commissioned for operation readiness in 2017. Here we describe the details and the components of the upgrade, and discuss the operational experience and results obtained during the upgrade and commissioning.

Commissioning of the CMS Hadron Forward Calorimeters Phase I Upgrade

Science.gov (United States)

Bilki, B.; Onel, Y.

2018-03-01

The final phase of the CMS Hadron Forward Calorimeters Phase I Upgrade was performed during the Extended Year End Technical Stop of 2016-2017. In the framework of the upgrade, the PMT boxes were reworked to implement two channel readout in order to exploit the benefits of the multi-anode PMTs in background tagging and signal recovery. The front-end electronics were also upgraded to QIE10-based electronics which implement larger dynamic range and a 6-bit TDC. Following this major upgrade, the Hadron Forward Calorimeters were commissioned for operation readiness in 2017. Here we describe the details and the components of the upgrade, and discuss the operational experience and results obtained during the upgrade and commissioning.

Linacs for medical and industrial applications

International Nuclear Information System (INIS)

Hamm, R.W.

1986-01-01

Linear accelerators for medical and industrial applications have become an important commercial business. Microwave electron linacs for cancer radiation therapy and high-energy industrial radiography form the bulk of this market, but these, as well as induction linacs, are now being offered for radiation processing applications such as sterilization of disposable medical products, food preservation and material modifications. The radio frequency quadrupole (RFQ) linac has now made the ion linac also practical for commercial applications in medicine and industry, including radiation therapy, isotope production, neutron production, materials modification, and energy transfer processes. Ion linacs for several of these applications will soon be commercially available. The market for both ion and electron linacs is expected to significantly grow in several exciting and important areas

Gas Injection And Fast Pressure-Rise Measurements For The Linac4 H− Source

CERN Document Server

Mahner, E; Lettry, J; Mattei, S; O'Neil, M; Neupert, H; Pasquino, C; Schmitzer, C

2013-01-01

In the era of the Large Hadron Collider, the CERN injector complex comprising the 34 years old Linac2 with its primary proton source, is presently upgraded with a new linear accelerator for H− (Linac4). The design, construction, and test of volume production and cesiated RF-driven H− ion sources is presently ongoing with the final goal of producing an H− beam with 80 mA beam current, 45 keV beam energy, 500 s pulse length, and a repetition rate of 2 Hz. In order to have quantitative information of the hydrogen gas density at the moment of plasma ignition the dynamic vacuum properties of the plasma generator were studied experimentally. We describe the experimental setup and present fast pressure-rise measurements for different parameters of the gas injection system, such as gas species (H2, He, N2, Ar), piezo valve voltage pulse length (200 - 500 s), and injection pressure (400 - 2800 mbar). The obtained data are compared with a conductance model of the plasma generator.

Testing begins on Linac4

CERN Multimedia

Katarina Anthony

2012-01-01

On 3 August 2012, the Linac4 radiofrequency quadrupole (RFQ) module was installed at the accelerator test-stand in Building 152. The site will be the module’s home for almost a year, as the linear accelerator enters the assembly and testing stage.   Final module assembly is carried out before installation in Building 152.  Over the next Long Shutdown (LS2), Linac4 will replace the current Linac2 linear accelerator as the first link in CERN’s accelerator chain. It will deliver particles at 160 MeV to the PS Booster, more than triple the energy currently delivered by Linac2. But before the accelerator team can pop the champagne, the various elements of Linac4 will be tested and re-tested in facilities across CERN. “The first Linac4 tests are currently underway, starting with the CERN-built RFQ,” says Carlo Rossi, a physicist in the RF Group of the Beams (BE) Department and the RFQ project coordinator. “It’s an extremely impre...

Light ion linacs for medical applications

International Nuclear Information System (INIS)

Bradbury, J.N.; Knapp, E.A.; Nagle, D.E.

1975-01-01

Recent advances in linear accelerator technology point to the feasibility of designing and developing practical medical linacs for producing protons, neutrons, or π mesons for the radiation therapy of cancer. Additional uses of such linacs could include radioisotope production and charged particle radiography. For widespread utilization medical linacs must exhibit reasonable cost, compactness, reliability, and simplicity of operation. Possible extensions of current accelerator technology which might provide these characteristics are discussed in connection with linac design, fabrication techniques, materials, power sources, injectors, and particle collection and delivery systems. Parameters for a medical proton linac for producing pions are listed. (U.S.)

Measurements of Linac4 H$^{-}$ ion source beam with a magnetized Einzel lens electron dump

CERN Document Server

Midttun, O; Scrivens, R

2014-01-01

Linac4 is a part of the upgrade of CERN’s accelerator complex for increased luminosity in the LHC. A new system to extract the ion beam from the plasma generator has been designed and tested, in order to improve the reliability and beam optics of the pulsed H- ion source. This paper presents the successfully implemented extraction system and three different beam measurements. The simulations compare well to the measurements and show that the plasma density was too low for the extraction system design during the measurements.

History, developments and recent performance of the CERN linac 1

International Nuclear Information System (INIS)

Haseroth, H.; Hill, C.E.; Langbein, K.; Tanke, E.; Tylor, C.; Tetu, P.; Warner, D.; Weiss, M.

1992-01-01

In early June 1992 the original CERN 50 MeV proton Linac accelerated its last beam after nearly 33 years of loyal service. Although conceived as a proton machine and commissioned in 1959 as an injector for the 26 GeV Proton Synchrotron, it finished its life as a light-ion source for the Super Proton Synchrotron (SPS) and as a cheap source of particles for tests in the Low Energy Anti-Proton Ring (LEAR). Highlights in its recent history were the installation of RFQs and the upgrading with an ECR source for O 6+ and S 12+ ions. The early parameters and the subsequent modifications as well as the performance are reviewed in this paper. (Author) 8 refs., 3 figs., tab

25th anniversary for Linac-2

CERN Multimedia

2003-01-01

On Friday, 3 October 2003, the Linac team celebrated a quarter century of successful operation of one of its linear accelerators: Linac-2, the proton workhorse of the CERN accelerator complex. Linac-2, CERN's linear proton accelerator, has now been running for 25 years - ample reason for a small celebration. About 30 members of the original team (10 of the initially more than 50 are still working at CERN), and other CERN personnel met on 3 October 2003. Linac-2 is the first link in the accelerator chain Linac-2 - PS Booster - PS - SPS and eventually LHC. Beams from Linac-2 are used after further acceleration in the CERN complex for SPS fixed target physics; for antiproton production for the Antiproton Decelerator (AD); for test beams in the East Experimental Hall and in the PS; for nuclear physics at ISOLDE; for LHC test beams and in the past for both ISR physics and Antiproton production (AA/AC) and test beams in LEAR. Linac-2 was built to obtain higher intensities and better stability than with ...

Workshop: Linac90

Energy Technology Data Exchange (ETDEWEB)

Van Dyck, Olin

1990-12-15

In 1960 the first linear accelerator (linac) conference was organized at Brookhaven by John Blewett. In the few years following, linear accelerator energies jumped from 50 MeV (at Brookhaven and CERN) to 2 GeV at Stanford. With the realization that, at least for electrons, circular accelerators have reached their practical limits, linacs are once more in the spotlight.

Workshop: Linac90

International Nuclear Information System (INIS)

Van Dyck, Olin

1990-01-01

In 1960 the first linear accelerator (linac) conference was organized at Brookhaven by John Blewett. In the few years following, linear accelerator energies jumped from 50 MeV (at Brookhaven and CERN) to 2 GeV at Stanford. With the realization that, at least for electrons, circular accelerators have reached their practical limits, linacs are once more in the spotlight

Injector linac of SPring-8

International Nuclear Information System (INIS)

Yoshikawa, H.; Hori, T.; Suzuki, S.; Yanagida, K.; Itoh, Y.; Mizuno, A.; Taniuchi, T.; Sakaki, H.; Kuba, A.; Fukushima, S.; Kobayashi, T.; Asaka, T.; Yokomizo, H.

1996-01-01

The linac that is SPring-8 injector was completed and started operation from August 1. A beam was able to be transported to the final beam dumping at a tail end on August 8. From now on this linac carries out beam adjustment and be scheduled to do a beam injection to a synchrotron in October. The construction and fundamental performance of the linac are described. (author)

Electron Linacs for High Energy Physics

International Nuclear Information System (INIS)

Wilson, Perry B.

2011-01-01

The purpose of this article is to introduce some of the basic physical principles underlying the operation of electron linear accelerators (electron linacs). Electron linacs have applications ranging from linacs with an energy of a few MeV, such that the electrons are approximately relativistic, to future electron-positron linear colliders having a collision energy in the several-TeV energy range. For the most part, only the main accelerating linac is treated in this article.

Design upgrade of the ISOLDE target unit for HIE-ISOLDE

CERN Document Server

Montano, J; Gottberg, A

2013-01-01

The High Intensity and Energy HIE-ISOLDE project is a major upgrade of the existing ISOLDE and REX-ISOLDE facilities with the objective of increasing the energy and the intensity of the delivered radioactive ion beams (RIB) {[}1]. In order to accommodate the future increase of primary beam intensity delivered by the new LINAC4 H- driver to the Proton Synchrotron Booster (PSB) {[}2] and from this to ISOLDE, a major study is being carried out to upgrade the existing designs of the ISOLDE target and its supporting infrastructure. In particular, the extraction optics plays an important role in the initial beam transport and the quality of the beam supplied to the mass separators. Important factors include the emittance of the beam and the beam profile to avoid beam losses. A new double electrode extraction system has been developed for simplifying and improving the interface between the target unit and the frontend (target coupling table). Numerical and experimental studies have been performed in order to define ...

Review of superconducting linacs

International Nuclear Information System (INIS)

Bollinger, L.M.

1992-01-01

This paper summarizes the status of the technology of superconducting (SC) linacs designed for the acceleration of ions. The emphasis is on the technical issues involved, with only brief descriptions of the numerous linacs now in operation or under construction. Recent developments of special interest are treated in more detail, and remaining technical challenges are outlined. The technology required for acceleration of ions with velocity β ∼ 1 is not discussed because it is almost the same as for relativistic electrons. That is, this paper is mainly about SC linacs for low-velocity heavy ions. (Author) 5 tabs., 6 figs., 29 refs

Review of induction LINACS

International Nuclear Information System (INIS)

Faltens, A.; Keefe, D.

1981-10-01

There has been a recent upsurge of activity in the field of induction linacs, with several new machines becoming operational and others in the design stages. The performance levels of electron machines have reached 10's of kiloamps of current and will soon reach 10's of MeV's of energy. Acceleration of ion current has been demonstrated, and the study of a 10 GeV heavy ion induction linac for ICF continues. The operating principles of induction linacs are reviewed with the emphasis on design choices which are important for increasing the maximum beam currents

Review of induction linacs

International Nuclear Information System (INIS)

Faltens, A.; Keefe, D.

1982-01-01

There has been a recent upsurge of activity in the field of induction linacs, with several new machines becoming operational and others in the design stages. The performance levels of electron machines have reached 10's of kiloamps of current and will soon reach 10's of MeV's of energy. Acceleration of several kiloamps of ion current has been demonstrated, and the study of a 10 GeV heavy ion induction linac for ICF continues. The operating principles of induction linacs are reviewed with the emphasis on design choices which are important for increasing the maximum beam currents

Low-charge-state linac

Energy Technology Data Exchange (ETDEWEB)

Shepard, K.W.; Kim, J.W.

1995-08-01

A design is being developed for a low-charge-state linac suitable for injecting ATLAS with a low-charge-state, radioactive beam. Initial work indicates that the existing ATLAS interdigital superconducting accelerating structures, together with the superconducting quadrupole transverse focussing element discussed above, provides a basis for a high-performance low-charge-state linac. The initial 2 or 3 MV of such a linac could be based on a normally-conducting, low-frequency RFQ, possibly combined with 24-MHz superconducting interdigital structures. Beam dynamics studies of the whole low-charge-state post-accelerator section were carried out in early FY 1995.

Commissioning of the CMS Hadron Forward Calorimeters Phase I Upgrade

CERN Document Server

Bilki, Burak

2017-01-01

The final phase of the CMS Hadron Forward Calorimeters Phase I upgrade is being performed during the Extended Year End Technical Stop of 2016 â?? 2017. In the framework of the upgrade, the PMT boxes are being reworked to implement two channel readout in order to exploit the benefits of the multi-anode PMTs in background tagging and signal recovery. The front-end electronics is also being upgraded to QIE10-based electronics which will implement larger dynamic range and a 6-bit TDC to eliminate the background to have an effect on the trigger. Following this major upgrade, the Hadron Forward Calorimeters will be commissioned for operation readiness in 2017. Here we describe the details and the components of the upgrade, and discuss the operational experience and results obtained during the upgrade and commissioning.

RESONANCE CONTROL FOR THE COUPLED CAVITY LINAC AND DRIFT TUBE LINAC STRUCTURES OF THE SPALLATION NEUTRON SOURCE LINAC USING A CLOSED-LOOP WATER COOLING SYSTEM

International Nuclear Information System (INIS)

Bernardin, J.D.; Brown, R.L.

2001-01-01

The Spallation Neutron Source (SNS) is a facility being designed for scientific and industrial research and development. SNS will generate and use neutrons as a diagnostic tool for medical purposes, material science, etc. The neutrons will be produced by bombarding a heavy metal target with a high-energy beam of protons, generated and accelerated with a linear particle accelerator, or linac. The low energy end of the linac consists of two room temperature copper structures, the drift tube linac (DTL), and the coupled cavity linac (CCL). Both of these accelerating structures use large amounts of electrical energy to accelerate the protons to an energy of 185 MeV. Approximately 60-80% of the electrical energy is dissipated in the copper structure and must be removed. This is done using specifically designed water cooling passages within the linac's copper structure. Cooling water is supplied to these cooling passages by specially designed resonance control and water cooling systems

Electron linac injector developments

International Nuclear Information System (INIS)

Fraser, J.S.

1986-01-01

There is a continuing demand for improved injectors for electron linacs. Free-electron laser (FEL) oscillators require pulse trains of high brightness and, in some applications, high average power at the same time. Wakefield-accelerator and laser-acceleration experiments require isolated bunches of high peak brightness. Experiments with alkali-halide photoemissive and thermionic electron sources in rf cavities for injector applications are described. For isolated pulses, metal photocathodes (illuminated by intense laser pulses) are being employed. Reduced emittance growth in high-peak-current electron injectors may be achieved by linearizing the cavity electric field's radial component and by using high field strengths at the expense of lower shunt impedance. Harmonically excited cavities have been proposed for enlarging the phase acceptance of linac cavities and thereby reducing the energy spread produced in the acceleration process. Operation of injector linacs at a subharmonic of the main linac frequency is also proposed for enlarging the phase acceptance

Heavy-ion-linac post-accelerators

International Nuclear Information System (INIS)

Bollinger, L.M.

1979-01-01

The main features of the tandem-linac system for heavy-ion acceleration are reviewed and illustrated in terms of the technology and performance of the superconducting heavy-ion energy booster at Argonne. This technology is compared briefly with the corresponding technologies of the superconducting linac at Stony Brook and the room-temperature linac at Heidelberg. The performance possibilities for the near-term future are illustrated in terms of the proposed extension of the Argonne booster to form ATLAS

Drift Tube Linac Conditioning of Tank1

CERN Document Server

Shafqat, N; Toor, W A

2014-01-01

Tank1 of the Drift Tube Linac (DTL) of the Linac4 has been conditioned at the Linac4 tunnel. The tank was tuned for resonance at 352.2 MHz, and stable operation has been achieved with 725 µs long RF pulses at a repetition rate of 1 Hz. The maximum RF level that has been reached is 810 kW with a pulse width of 600 µs. Since this was the first RF structure exclusively conditioned in the Linac4 tunnel with the operation and control software of Linac4, some related issues and limitations had to be taken into account.

Commissioning of the Linac4 RFQ at the 3 MeV test stand

CERN Document Server

Rossi, C; Bellodi, G; Broere, J; Brunner, O; Lombardi, A M; Balula, J M; Yanez, P M; Noirjean, J; Pasquino, C; Raich, U; Roncarolo, F; Vretenar, M; Desmons, M; France, A; Piquet, O

2013-01-01

Linac4, the future 160 MeV Hˉ injector to the CERN Proton Synchrotron Booster, is presently under construction at CERN as a first step of the planned upgrade of the LHC injectors. The low energy section of LINAC4, consisting of an ion source, a 352.2 MHz Radio Frequency Quadrupole (RFQ) and a chopper line is being commissioned in a dedicated test stand before installation in its final position in the tunnel. The RFQ is designed to accelerate a 45 keV, 70 mA, Hˉ beam to 3 MeV, with an efficiency of 95% while preserving the transverse emittance. The RFQ, a four-vane structure 3 m in length, has been designed in collaboration with CEA/IRFU and is has been fabricated at the CERN workshop. The precise fabrication has allowed achieving a field flatness of 1%. The completion of the accelerating structure in September 2012 was followed by a complete series of bead-pull measurements and by high-power conditioning to the nominal power of 0.39 MW corresponding to a voltage of 78 kV across the 3 meters. Measurements wi...

3D Emittances Tailoring Techniques and Optimization with Space Charge for the Future CERN PS Booster Operations with Linac4

CERN Document Server

Forte, Vincenzo; Benedetto, Elena; Bracco, Chiara; Cieslak-Kowalska, Magdalena; Di Giovanni, Gian Piero

2016-01-01

In the frame of the LIU (LHC Injectors Upgrade) project, the CERN PS Booster is going to be renovated to host a new H⁻ charge-exchange injection from the Linac4. One important feature of the new injection scheme is the possibility to tailor a wide range of 3D emittances for CERN's different users in an intensity span in the order of 5·10⁹ to 1.6·10¹³ protons per PSB ring. This paper gives an overview of 3D multi-turn injection techniques, focusing on the future LHC beams, which aim at reaching high brightness, and on highest intensity beams (ISOLDE), where losses are the main concern. Complete RF capture simulations and transverse injection maps, including space charge effects, are presented and also intended to be used during the commissioning with Linac4.

Recovery from disasters of the Tohoku earthquake (March 11, 2011)

International Nuclear Information System (INIS)

Hama, Hiroyuki

2012-01-01

Everyone living in Tohoku area was beaten both physically and psychologically due to the Tohoku Earthquake March 11, 2011, and recovery of the towns suffered the tsunami damage is not yet under way. An old accelerator facility in Electron Light Science Centre, Tohoku University suffered serious damage as well. A 46-year-old 300 MeV electron linac has gotten into malfunction. Though we gave up to recover the 300 MeV linac, the low energy part of the linac is going to be rebuilt. A small linac will be constructed as an injector for the booster ring. Because of limited budget, the upper bound of the beam energy will be 90 MeV. In addition, power supplies for a 1.2 GeV booster synchrotron that have mostly failed will be replaced. (author)

Statistical simulations of machine errors for LINAC4

CERN Document Server

Baylac, M.; Froidefond, E.; Sargsyan, E.

2006-01-01

LINAC 4 is a normal conducting H- linac proposed at CERN to provide a higher proton flux to the CERN accelerator chain. It should replace the existing LINAC 2 as injector to the Proton Synchrotron Booster and can also operate in the future as the front end of the SPL, a 3.5 GeV Superconductingg Proton Linac. LINAC 4 consists of a Radio-Frequency Quadrupole, a chopper line, a Drift Tube Linac (DTL) and a Cell Coupled DTL all operating at 352 MHz and finally a Side Coupled Linac at 704 MHz. Beam dynamics was studied and optimized performing end-to-end simulations. This paper presents statistical simulations of machine errors which were performed in order to validate the proposed design.

Commissioning plans for SSC linac

International Nuclear Information System (INIS)

Hurd, J.W.; Aprile, R.L.; Chang, C.R.; Crist, C.E.; Cutler, R.I.; Funk, L.W.; Guy, F.W.; Leifeste, G.T.; Raparia, D.; Saadatmand, K.; Sethi, R.C.; Swenson, D.A.; Tooker, J.; Yao, C.G.

1992-01-01

Presented are the general description of the SSC linac and the plans for commissioning. Sections of the linac are installed, tested, and beam commissioned in a serial approach. A specialized set of diagnostics is used to characterize the beam through each section. In addition to the standard diagnostic set, plans call for the use of a bunch shape monitor and x-ray spectrometer. Streak camera and digital imaging diagnostics will be developed. The commissioning plan is folded into the general linac project schedule to show the relation between delivery, staging, installation, conditioning, and actual commissioning with beam. These plans form the basis for coordination between the various organizations responsible for different elements of the linac including the technical components, infrastructure, and temporary staging and operation facilities. (Author) 2 figs., 17 refs

High gradient linac for proton therapy

Directory of Open Access Journals (Sweden)

S. Benedetti

2017-04-01

Full Text Available Proposed for the first time almost 30 years ago, the research on radio frequency linacs for hadron therapy experienced a sparkling interest in the past decade. The different projects found a common ground on a relatively high rf operating frequency of 3 GHz, taking advantage of the availability of affordable and reliable commercial klystrons at this frequency. This article presents for the first time the design of a proton therapy linac, called TULIP all-linac, from the source up to 230 MeV. In the first part, we will review the rationale of linacs for hadron therapy. We then divided this paper in two main sections: first, we will discuss the rf design of the different accelerating structures that compose TULIP; second, we will present the beam dynamics design of the different linac sections.

The LINAC4 Project at CERN

CERN Document Server

Arnaudon, L; Bertone, C; Body, Y; Broere, J; Brunner, O; Buzio, M; Carli, C; Caspers, F; Corso, JP; Coupard, J; Dallocchio, A; Dos Santos, N; Garoby, R; Gerigk, F; Hammouti, L; Hanke, K; Jones, M; Kozsar, I; Lettry, J; Lallement, JB; Lombardi, A; Lopez-Hernandez, LA; Maglioni, C; Mathot, S; Maury, S; Mikulec, B; Nisbet, D; Noels, C; Paoluzzi, M; Puccio, B; Raich, U; Ramberger, S; Rossi, C; Schwerg, N; Scrivens, R; Vandoni, G; Weisz, S; Vollaire, J; Vretenar, M; Zickler, T

2011-01-01

As the first step of a long-term programme aiming at an increase in the LHC luminosity, CERN is building a new 160 MeV H¯ linear accelerator, Linac4, to replace the ageing 50 MeV Linac2 as injector to the PS Booster (PSB). Linac4 is an 86-m long normal-conducting linac made of an H¯ source, a Radio Frequency Quadrupole (RFQ), a chopping line and a sequence of three accelerating structures: a Drift-Tube Linac (DTL), a Cell-Coupled DTL (CCDTL) and a Pi-Mode Structure (PIMS). The civil engineering has been recently completed, and construction of the main accelerator components has started with the support of a network of international collaborations. The low-energy section up to 3 MeV including a 3-m long 352 MHz RFQ entirely built at CERN is in the final construction phase and is being installed on a dedicated test stand. The present schedule foresees beam commissioning of the accelerator in the new tunnel in 2013/14; the moment of connection of the new linac to the CERN accelerator chain will depend on the L...

The Superconducting Super Collider (SSC) linac

International Nuclear Information System (INIS)

Watson, J.M.

1990-09-01

The preliminary design of the 600 MeV H - linac for the Superconducting Super Collider injector is described. The linac must provide a 25 mA beam during 7--35 μs macropulses at Hz within injection bursts. Normalized transverse emittances of less than 0.5 π mm-mrad (rms) are required for injection into the Low Energy Booster synchrotron. Cost, ease of commissioning, and operational reliability are important considerations. The linac will consists of an H - source with electrostatic LEBT, 2.5 MeV radiofrequency quadrupole accelerator, a 70 MeV drift-tube linac, and 530 MeV and the side-coupled linac operates at 1284 MHz. A modest total length of 150 m results from the tradeoff between cost optimization and reliability. The expected performance from beam dynamics simulations and the status of the project are described. 11 refs., 1 fig., 6 tabs

A 2--4 nm Linac Coherent Light Source (LCLS) using the SLAC linac

International Nuclear Information System (INIS)

Winick, H.; Bane, K.; Boyce, R.

1993-05-01

We describe the use of the SLAC linac to drive a unique, powerful. short wavelength Linac Coherent Light Source (LCLS). Operating as an FEL, lasing would be achieved in a single pass of a high peak current electron beam through a long undulator by self-amplified spontaneous emission (SASE). The main components are a high-brightness rf photocathode electron gun; pulse compressors; about 1/5 of the SLAC linac; and a long undulator with a FODO quadrupole focussing system. Using electrons below 8 GeV, the system would operate at wavelengths down to about 3 nm, producing ≥10 GW peak power in sub-ps pulses. At a 120 Hz rate the average power is ∼ 1 W

Review of superconducting ion linacs

International Nuclear Information System (INIS)

Bollinger, L.M.

1992-01-01

This paper summarizes the status of the technology of superconducting (SC) linacs designed for the acceleration of ions. The emphasis is on the technical issues involved, with only brief descriptions of the numerous linacs now in operation or under construction. Recent developments of special interest are treated in more detail, and remaining technical challenges are outlined. The technology required for the acceleration of ions with velocity β=1 is not discussed because it is almost the same as for relativistic electrons. That is, this paper is mainly about SC linacs for low-velocity heavy ions

Cryogenic system for the Energy Recovery Linac and vertical test facility at BNL

International Nuclear Information System (INIS)

Than, R.; Soria, V.; Lederle, D.; Orfin, P.; Porqueddu, R.; Talty, P.; Zhang, Y.; Tallerico, T.; Masi, L.

2011-01-01

A small cryogenic system and warm helium vacuum pumping system provides cooling to either the Energy Recovery Linac's (ERL) cryomodules that consist of a 5-cell cavity and an SRF gun or a large Vertical Test Dewar (VTD) at any given time. The cryogenic system consists of a model 1660S PSI piston plant, a 3800 liter storage dewar, subcooler, a wet expander, a 50 g/s main helium compressor, and a 170 m 3 storage tank. A system description and operating plan of the cryogenic plant and cryomodules is given. The cryogenic system for ERL and the Vertical Test Dewar has a plant that can produce the equivalent of 300W at 4.5K with the addition of a wet expander 350 W at 4.5K. Along with this system, a sub-atmospheric, warm compression system provides pumping to produce 2K at the ERL cryomodules or the Vertical Test Dewar. The cryogenic system for ERL and the Vertical Test Dewar makes use of existing equipment for putting a system together. It can supply either the ERL side or the Vertical Test Dewar side, but not both at the same time. Double valve isolation on the liquid helium supply line allows one side to be warmed to room temperature and worked on while the other side is being held at operating temperature. The cryogenic system maintain the end loads from 4.4K to 2K or colder depending on capacity. Liquid helium storage dewar capacity allows ERL or the VTD to operate above the plant's capacity when required and ERL cryomodules ballast reservoirs and VTD reservoir allows the end loads to operate on full vacuum pump capacity when required.

Design study of the large hadron electron collider and a rapid cycling synchrotron as alternative to the PS booster upgrade at CERN

International Nuclear Information System (INIS)

Fitterer, Miriam

2013-01-01

With the Large Hadron Collider (LHC) the exploration of particle physics at center of mass energies at the TeV scale has begun. To extend the discovery potential of the LHC, a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors - the chain of accelerators preparing the beam for the LHC. One of the injectors - the second one in the chain - is the Proton Synchrotron (PS) Booster. Its performance is currently limited by the space-charge effect, which is the effect of the electromagnetic field of the particle beam on itself. This effect becomes weaker with higher energy, and therefore an energy upgrade of the PS Booster to 2 GeV maximum beam energy is foreseen. As the PS Booster is with its 40 years already an old machine, the construction of a new accelerator, a Rapid Cycling Synchrotron (RCS), to replace the PS Booster has been proposed. In this thesis different options for the beam guidance in the RCS - referred to as lattice and optics - are studied, followed by a more general comparison of different lattices and optics and their performance under consideration of the space-charge effect. To further complement the LHC physics program, also the possibility of deep inelastic lepton-nucleon scattering at the LHC has been suggested, referred to as Large Hadron Electron Collider (LHeC). In this case the proton beam of the LHC collides with the electron beam, which is accelerated in a separate newly built machine. Two options are considered as electron accelerator: a new energy recovery linac - the Linac-Ring option - and the installation of an electron ring in the existing LHC tunnel - the Ring-Ring option. One of the main challenges of the Ring-Ring option is the integration of the electron ring in the current LHC tunnel. A layout, lattice and optics of the electron accelerator is developed in this thesis, which meets the requirements with regard to integration and reaches the beam parameters demanded by the particle physics experiments.

Design study of the large hadron electron collider and a rapid cycling synchrotron as alternative to the PS booster upgrade at CERN

Energy Technology Data Exchange (ETDEWEB)

Fitterer, Miriam

2013-02-22

With the Large Hadron Collider (LHC) the exploration of particle physics at center of mass energies at the TeV scale has begun. To extend the discovery potential of the LHC, a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors - the chain of accelerators preparing the beam for the LHC. One of the injectors - the second one in the chain - is the Proton Synchrotron (PS) Booster. Its performance is currently limited by the space-charge effect, which is the effect of the electromagnetic field of the particle beam on itself. This effect becomes weaker with higher energy, and therefore an energy upgrade of the PS Booster to 2 GeV maximum beam energy is foreseen. As the PS Booster is with its 40 years already an old machine, the construction of a new accelerator, a Rapid Cycling Synchrotron (RCS), to replace the PS Booster has been proposed. In this thesis different options for the beam guidance in the RCS - referred to as lattice and optics - are studied, followed by a more general comparison of different lattices and optics and their performance under consideration of the space-charge effect. To further complement the LHC physics program, also the possibility of deep inelastic lepton-nucleon scattering at the LHC has been suggested, referred to as Large Hadron Electron Collider (LHeC). In this case the proton beam of the LHC collides with the electron beam, which is accelerated in a separate newly built machine. Two options are considered as electron accelerator: a new energy recovery linac - the Linac-Ring option - and the installation of an electron ring in the existing LHC tunnel - the Ring-Ring option. One of the main challenges of the Ring-Ring option is the integration of the electron ring in the current LHC tunnel. A layout, lattice and optics of the electron accelerator is developed in this thesis, which meets the requirements with regard to integration and reaches the beam parameters demanded by the particle physics experiments.

Magnet innovations for linacs

International Nuclear Information System (INIS)

Halbach, K.

1986-01-01

It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results of past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs are presented

Magnet innovations for linacs

International Nuclear Information System (INIS)

Halbach, K.

1986-06-01

It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results will be presented about past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs

The JAERI superconducting RF linac-based FELS and THEIR cryogenics

International Nuclear Information System (INIS)

Minehara, Eisuke J.

2003-01-01

In the 21st century, we need a powerful and efficient free-electron laser (FEL) for academic and industrial uses in almost all fields. In order to realize such a tunable, highly-efficient, high average power, high peak power and ultra-short pulse FEL, the JAERI FEL group and I have developed an industrial FEL driven by a compact, stand-alone and zero-boil off super-conducting rf linac with an energy-recovery geometry. Our discussions on the JAERI FEL and cryogenics will cover market-requirements for the industrial FELs, some answers from the JAERI compact, stand-alone and zero-boil off cryostat concept and operational experiences over these 9 years, our discovery of the new, highly-efficient, high-power, and ultra-short pulse lasing mode, and the energy-recovery geometry. (author)

Superconducting heavy-ion linac at Argonne

International Nuclear Information System (INIS)

Aron, J.; Benaroya, R.; Bollinger, L.M.; Clifft, B.G.; Johnson, K.W.; Nixon, J.M.; Markovich, P.; Pardo, R.C.; Shepard, K.W.

1981-01-01

The design, status, and performance of the first operating superconducting heavy-ion accelerator, a linac used to boost the energies of beams from a 9-MV tandem, is summarized. When completed in 1981, the linac will consist of 24 independently-phased split-ring niobium resonators operating at 97 MHz. This linac is designed to provide 29 MV of acceleration. Because of the modular character of the system, the linac has been operable and useful since mid-1978, when a beam was accelerated through 2 units and the first nuclear-physics experiments were preformed. Now, 16 resonators are in use, and a beam has been accelerated for approx. 6000 h. Resonator performance has been remarkably stable, in spite of vacuum accidents, and the linac as a whole operates reliably without operators in attendance during nights and weekends. The ease and speed with which the beam energy can be changed is proving to be unexpectedly valuable to users

The trajectory control in the SLC linac

International Nuclear Information System (INIS)

Hsu, I.C.; Adolphsen, C.E.; Himel, T.M.; Seeman, J.T.

1991-05-01

Due to wake field effects, the trajectories of accelerated beams in the Linac should be well maintained to avoid severe beam breakup. In order to maintain a small emittance at the end of the Linac, the tolerance on the trajectory deviations become tighter when the beam intensities increase. The existing two beam trajectory correction method works well when the theoretical model agrees with the real machine lattice. Unknown energy deviations along the linac as well as wake field effects can cause the real lattice to deviate from the model. This makes the trajectory correction difficult. Several automated procedures have been developed to solve these problems. They are: an automated procedure to frequently steer the whole Linac by dividing the Linac into several small regions; an automated procedure to empirically correct the model to fit the real lattice and eight trajectory correcting feedback loops along the linac and steering through the collimator region with restricted corrector strengths and a restricted number of correctors. 6 refs., 2 figs

Development of an IH-type linac for the acceleration of high current heavy ion beams

Energy Technology Data Exchange (ETDEWEB)

Haehnel, Jan Hendrik

2017-07-20

The Facility for Antiproton and Ion Research (FAIR) at GSI Darmstadt will provide unprecedented intensities of protons and heavy ions up to uranium at energies of up to 29 GeV for protons and 2.7 GeV/u for U{sup 28+}. To achieve high intensities in the synchrotron accelerators, high beam currents have to be provided by the injector linear accelerators. High current heavy ion beams are provided by the Universal Linear Accelerator (UNILAC), which in its current state will not be able to provide the required FAIR beam currents. This thesis deals with the development of upgrades for the UNILAC to ensure its high current capability. The first improvement is a matching section (MEBT) for the interface between the RFQ and the IH-DTL of the existing high current injector HSI at the UNILAC. With this new MEBT section, particle losses are eliminated and the overall beam quality is improved. As a second improvement, a complete replacement of the existing Alvarez-DTL is presented. A combination of efficient IH-type cavities and KONUS beam dynamics results in a reduction of the linac length from about 60 m (Alvarez) to just 23 m (new IH-DTL) while providing the same energy and fulfilling FAIR requirements of a high beam current and beam quality. This thesis contains a detailed beam dynamics design of the new linac including some fundamental investigations of the KONUS beam dynamics concept. A cross-check of the beam dynamics design was performed with two independent multi-particle simulation codes. Detailed error studies were conducted to investigate the influence of manufacturing, alignment and operating errors on the beam dynamics performance. Additionally, all five linac cavities were designed, optimized, and their RF parameters including power requirements calculated to provide a comprehensive linac design.

Development of an IH-type linac for the acceleration of high current heavy ion beams

International Nuclear Information System (INIS)

Haehnel, Jan Hendrik

2017-01-01

The Facility for Antiproton and Ion Research (FAIR) at GSI Darmstadt will provide unprecedented intensities of protons and heavy ions up to uranium at energies of up to 29 GeV for protons and 2.7 GeV/u for U 28+ . To achieve high intensities in the synchrotron accelerators, high beam currents have to be provided by the injector linear accelerators. High current heavy ion beams are provided by the Universal Linear Accelerator (UNILAC), which in its current state will not be able to provide the required FAIR beam currents. This thesis deals with the development of upgrades for the UNILAC to ensure its high current capability. The first improvement is a matching section (MEBT) for the interface between the RFQ and the IH-DTL of the existing high current injector HSI at the UNILAC. With this new MEBT section, particle losses are eliminated and the overall beam quality is improved. As a second improvement, a complete replacement of the existing Alvarez-DTL is presented. A combination of efficient IH-type cavities and KONUS beam dynamics results in a reduction of the linac length from about 60 m (Alvarez) to just 23 m (new IH-DTL) while providing the same energy and fulfilling FAIR requirements of a high beam current and beam quality. This thesis contains a detailed beam dynamics design of the new linac including some fundamental investigations of the KONUS beam dynamics concept. A cross-check of the beam dynamics design was performed with two independent multi-particle simulation codes. Detailed error studies were conducted to investigate the influence of manufacturing, alignment and operating errors on the beam dynamics performance. Additionally, all five linac cavities were designed, optimized, and their RF parameters including power requirements calculated to provide a comprehensive linac design.

System engineering in the SSC Linac

International Nuclear Information System (INIS)

Tooker, J.F.; Chang, C.R.; Cutler, R.I.; Funk, L.W.; Guy, F.W.; Hale, R.; Leifeste, G.T.; Nonte, J.; Prichard, B.; Raparia, D.; Saadatmand, K.; Sethi, R.C.; Yao, C.G.

1992-01-01

The design and construction of the SSC Linac involves various departments within the SSCL and many outside vendors. The adaptive incorporation of system engineering principles into the SSC Linac is described. This involves the development of specification trees with the breakdown and flow of functional and physical requirements from the top level system specifications to the lower level component specifications. Interfaces are defined, which specify and control the interconnections between the various components. Review cycles are presented during which the requirements, evolution of the design, and test plans are reviewed, monitored, and finalized. The Linac specification tree, interface definition, and reviews of the Linac are presented, including typical examples. (Author) 2 refs., 3 tabs

Linac4 H{sup −} ion sources

Energy Technology Data Exchange (ETDEWEB)

Lettry, J., E-mail: Jacques.lettry@cern.ch; Aguglia, D.; Andersson, P.; Bertolo, S.; Butterworth, A.; Coutron, Y.; Dallocchio, A.; David, N.; Chaudet, E.; Fink, D. A.; Garlasche, M.; Grudiev, A.; Guida, R.; Hansen, J.; Haase, M.; Jones, A.; Koszar, I.; Lallement, J.-B.; Lombardi, A. M.; Machado, C. [CERN-ABP, 1211 Geneva 23 (Switzerland); and others

2016-02-15

CERN’s 160 MeV H{sup −} linear accelerator (Linac4) is a key constituent of the injector chain upgrade of the Large Hadron Collider that is being installed and commissioned. A cesiated surface ion source prototype is being tested and has delivered a beam intensity of 45 mA within an emittance of 0.3 π ⋅ mm ⋅ mrad. The optimum ratio of the co-extracted electron- to ion-current is below 1 and the best production efficiency, defined as the ratio of the beam current to the 2 MHz RF-power transmitted to the plasma, reached 1.1 mA/kW. The H{sup −} source prototype and the first tests of the new ion source optics, electron-dump, and front end developed to minimize the beam emittance are presented. A temperature regulated magnetron H{sup −} source developed by the Brookhaven National Laboratory was built at CERN. The first tests of the magnetron operated at 0.8 Hz repetition rate are described.

A Very Intense Neutrino Super Beam Experiment for Leptonic CP Violation Discovery based on the European Spallation Source Linac: A Snowmass 2013 White Paper

CERN Document Server

Baussan, E; Bogomilov, M.; Bouquerel, E.; Cederkäll, J.; Christiansen, P.; Coloma, P.; Cupial, P.; Danared, H.; Densham, C.; Dracos, M.; Ekelöf, T.; Eshraqi, M.; Fernandez Martinez, E.; Gaudiot, G.; Hall-Wilton, R.; Koutchouk, J.P.; Lindroos, M.; Matev, R.; McGinnis, D.; Mezzetto, M.; Miyamoto, R.; Mosca, L.; Ohlsson, T.; Öhman, H.; Osswald, F.; Peggs, S.; Poussot, P.; Ruber, R.; Tang, J.Y.; Tsenov, R.; Vankova-Kirilova, G.; Vassilopoulos, N.; Wildner, E.; Wurtz, J.

2014-01-01

Very intense neutrino beams and large neutrino detectors will be needed in order to enable the discovery of CP violation in the leptonic sector. We propose to use the proton linac of the European Spallation Source currently under construction in Lund, Sweden to deliver, in parallel with the spallation neutron production, a very intense, cost effective and high performance neutrino beam. The baseline program for the European Spallation Source linac is that it will be fully operational at 5 MW average power by 2022, producing 2 GeV 2.86 ms long proton pulses at a rate of 14 Hz. Our proposal is to upgrade the linac to 10 MW average power and 28 Hz, producing 14 pulses/s for neutron production and 14 pulses/s for neutrino production. Furthermore, because of the high current required in the pulsed neutrino horn, the length of the pulses used for neutrino production needs to be compressed to a few $\\mu$s with the aid of an accumulator ring. A long baseline experiment using this Super Beam and a megaton underground ...

Installation and Commissioning of the CMS Hadron Forward Calorimeters Phase I Upgrade

CERN Document Server

Onel, Yasar

2017-01-01

The final phase of the CMS Hadron Forward Calorimeters Phase I upgrade was performed during the Extended Year End Technical Stop of 2016-2017. In the framework of the upgrade, the PMT boxes were reworked to implement two channel readout in order to exploit the benefits of the multi-anode PMTs in background tagging and signal recovery. The front-end electronics was also being upgraded to QIE10-based electronics which will implement larger dynamic range and a 6-bit TDC to provide additional handles to eliminate the background. Following this major upgrade, the Hadron Forward Calorimeters are being commissioned for operation readiness in 2017. Here we describe the details and the components of the upgrade, and discuss the operational experience and results obtained during the upgrade and commissioning.

Preliminary design of a dedicated proton therapy linac

International Nuclear Information System (INIS)

Hamm, R.W.; Crandall, K.R.; Potter, J.M.

1991-01-01

The preliminary design has been completed for a low current, compact proton linac dedicated to cancer therapy. A 3 GHz side-coupled structure accelerates the beam from a 70 MeV drift tube linac using commercially available S-band rf power systems and accelerating cavities. This significantly reduces the linac cost and allows incremental energies up to 250 MeV. The short beam pulse width and high repetition rate make the linac similar to the high energy electron linacs now used for cancer therapy, yet produce a proton flux sufficient for treatment of large tumors. The high pulse repetition rate permits raster scanning, and the small output beam size and emittance result in a compact isocentric gantry design. Such a linac will reduce the facility and operating costs for a dedicated cancer therapy system

SUPERCONDUCTING LINAC FOR THE SPALLATION NEUTRON SOURCE

International Nuclear Information System (INIS)

STOVALL, J.; NATH, S.

2000-01-01

The Spallation Neutron Source (SNS) linac is comprised of both normal and superconducting rf (SRF) accelerating structures. The SRF linac accelerates the beam from 186 to 1250 MeV through 117 elliptical, multi-cell niobium cavities. This paper describes the SRF linac architecture, physics design considerations, cavity commissioning, and the expected beam dynamics performance

Project scenarios for bitumen upgrading

International Nuclear Information System (INIS)

Koppel, P.E.; Mazurek, W.L.; Harji, A.

2002-01-01

The established reserves of Alberta's heavy oil resources are 178 billion barrels, and potential recoverable reserves are 315 billion barrels. The challenge of production includes the logistics of recovery, upgrading and transportation to market. Utilization of the bitumen is not simple because bitumen is too viscous to transport by pipeline. In addition, it is not processable by most existing refineries unless it can be upgraded through dilution. This paper examined different factors regarding the economic viability of various upgrading methods of a wide range of bitumen feedstocks. The study also examined the sensitivity of refinery demand to the prices of these feedstocks, along with the competitiveness among bitumen-based feedstock and conventional crudes. Western Canada, Ontario and the PADD II district in the United States are the 3 major markets for western Canadian bitumen based feedstock, the demand for which depends on refinery configurations and asphalt demand. This paper described the following 4 generic scenarios that describe Alberta bitumen upgrading projects: (1) adjacent to open pit mines, (2) adjacent to steam assisted gravity drainage (SAGD) facilities, (3) remotely located from resource production at an existing refinery, and (4) pipeline bitumen. It was noted that producers should determine the best way to upgrade the bitumen to ensure there is an economic market for the product, but they should also be aware not to over process the bitumen so as not to leave existing refinery facilities under-utilized. 2 refs., 1 tab., 3 figs

Magnetron based high energy S-band linac system

International Nuclear Information System (INIS)

Tiwari, T.; Krishnan, R.; Phatangare, Manoj

2012-01-01

This paper deals with the study of magnetron based high energy S-band linear accelerator (linac) system operating at spot frequency 2.998 GHz. The energy and dose are two important parameters of linac system which depend on input power of microwave source and length of linac tube. Here the author has studied how these parameters can be improved for side coupled standing wave S-band linac system

Linac4 crosses the 100 MeV threshold

CERN Multimedia

Corinne Pralavorio

2016-01-01

The new linear accelerator, which from 2020 will be the first link in the accelerator chain, has entered a new stage of its commissioning.   Members of the team in charge of the commissioning of Linac4 in the accelerator’s control room. A few hours earlier, Linac4 accelerated a beam to 107 MeV for the first time. We couldn’t have imagined a more appropriate date: on 1 July (1.07), Linac4 reached an energy of 107 MeV. Having crossed the 100 MeV barrier, the linear accelerator is now on the home straight of its commissioning. “This stage was very quick – it took less than two weeks,” says Alessandra Lombardi, deputy project leader of Linac4, in charge of the commissioning. In 2020, Linac4 will replace the existing Linac2 as the first link in the accelerator chain. It will accelerate beams of H- ions (protons surrounded by two electrons) to 160 MeV, compared to 50 MeV with Linac2. The new machine is particularly sophisticated as it comprises...

TOP LINAC design

International Nuclear Information System (INIS)

Picardi, L.; Ronsivalle, C.; Vignati, A.

1997-11-01

The report describes a linear accelerator for protons named TOP LINAC designed for the TOP (Terapia Oncologica con Protoni, Oncological Protontherapy) project launched by the Italian National Institute of Health (Istituto Superiore di Sanita', ISS) to explore in collaboration with the biggest Oncological Hospital in Rome (Istituto Regina Elena, IRE) the potentialities of the therapy with accelerated protons and establish guide lines for the application of this new type of radiotherapy in comparison with the more traditional electron and x-rays radiotherapy. The concept of a compact accelerator for protontherapy applications bore within the Italian Hadrontherapy Collaboration (TERA Collaboration) with the aim to diffuse the protontherapy on the National territory. The ISS program plans to use the TOP linac proton beam also for production of PET (Positron Emission Tomography) radioisotopes and radiobiology studies. Official agreements are in course between ISS and ENEA which provides its experience in the industrial and medical accelerators for the design and the construction of the TOP linac. The accelerator that will be the first 3 GHz proton linac in the world, will be composed of a 428.3 MHz 7 Me V RFQ + DTL injector followed by a 7-65 Me V section of a 3 GHz SCDTL structure and a 65 - 200 Me V variable energy SCL 3 GHz structure. In particular the SCDTL section uses a highly innovative accelerating structure patented by ENEA. In this report the clinical and physical requests are discussed and a preliminary design of the whole machine is given

Radiotechnical Institute activity in the linac field

International Nuclear Information System (INIS)

Murin, B.P.

1976-01-01

For many years, the Radiotechnical Institute has been involved in a number of projects aimed at constructing linear accelerators for protons or electrons. This report summarizes the experience gained and covers 1) some problems of developing linacs to serve as meson or neutron generators, 2) results of study of a linac with asymmetric alternating phase focusing, and 3) electron linac projects. (author)

IMPACT simulation and the SNS linac beam

International Nuclear Information System (INIS)

Zhang, Y.; Qiang, J.

2008-01-01

Multi-particle tracking simulations for the SNS linac beam dynamics studies are performed with the IMPACT code. Beam measurement results are compared with the computer simulations, including beam longitudinal halo and beam losses in the superconducting linac, transverse beam Courant-Snyder parameters and the longitudinal beam emittance in the linac. In most cases, the simulations show good agreement with the measured results

Proton induction linacs as high-intensity neutron sources

International Nuclear Information System (INIS)

Keefe, D.; Hoyer, E.

1981-01-01

Proton induction linacs are explored as high intensity neutron sources. The induction linac - concept, properties, experience with electrons, and possibilities - and its limitations for accelerating ions are reviewed. A number of proton induction linac designs are examined with the LIACEP program and general conclusions are given. Results suggest that a proton induction accelerator of the lowest voltage, consistent with good neutron flux, is preferred and could well be cost competitive with the usual rf linac/storage ring designs. (orig.)

Status of the RF-driven H− ion source for J-PARC linac

International Nuclear Information System (INIS)

Oguri, H.; Ohkoshi, K.; Ikegami, K.; Takagi, A.; Asano, H.; Ueno, A.; Shibata, T.

2016-01-01

For the upgrade of the Japan Proton Accelerator Research Complex linac beam current, a cesiated RF-driven negative hydrogen ion source was installed during the 2014 summer shutdown period, with subsequent operations commencing on September 29, 2014. The ion source has been successfully operating with a beam current and duty factor of 33 mA and 1.25% (500 μs and 25 Hz), respectively. The result of recent beam operation has demonstrated that the ion source is capable of continuous operation for approximately 1100 h. The spark rate at the beam extractor was observed to be at a frequency of less than once a day, which is an acceptable level for user operation. Although an antenna failure occurred during operation on October 26, 2014, no subsequent serious issues have occurred since then

25 years of Pelletron Linac facility

International Nuclear Information System (INIS)

Shrivastava, A.; Palit, R.

2014-01-01

The DAE-BRNS International Symposium on Nuclear Physics was held in BARC during 2nd to 6th December 2013. A summary of the highlights of this symposium has recently appeared in Physics News. As a part of the symposium, a special session was held to commemorate 25 years of operation of the Mumbai Pelletron Linac Facility (PLF). PLF, being operated jointly by Bhabha Atomic Research Centre and Tata Institute of Fundamental Research, has been a major centre for heavy-ion accelerator based research in India. The Pelletron accelerator was formally inaugurated on 30th December 1988, and marked an important milestone in nuclear physics research in India. The facility was augmented with the indigenously developed superconducting LINAC booster to enhance the energy of the accelerated beams. The LINAC booster was commissioned in a phased manner and the entire facility was dedicated to the users on the 28th November 2007. The LINAC booster consists of seven liquid helium cryostat modules, each housing four lead coated (2 μm) copper quarter wave resonators (QWR). The cavities are designed to operate at 150 MHz with an optimum acceptance at a velocity corresponding to β=0.1. The performance of the QWRs is found to be excellent with an average energy gain of 0.4 MV/q per cavity corresponding to 80% of the design value. Beam transmission from the entry to the exit of the LINAC was found to be 80% and the beam timing (FWHM) of 600 ps was measured at the target position. Development of the superconducting LINAC is a major milestone in the accelerator technology in our country. Most of the critical components of the LINAC booster, the first superconducting heavy-ion accelerator in India, have been designed, developed and fabricated indigenously

Techno-economic analysis of resource recovery technologies for wastewater treatment plants

DEFF Research Database (Denmark)

Boiocchi, Riccardo; Matafome, Beatriz; Loureiro da Costa Lira Gargalo, Carina

2017-01-01

resource-recovery treatment units: (a) a chemical precipitation process, for recovery of iron phosphate fertilizer; (b) the Exelys technology, for increased biogas production; and, (c) the Phosnix technology, for recovery of struvite fertilizer. Seven upgrade strategies/flowsheets employing different...... upgrading combinations involving chemical precipitation and Exelys technologies were not found economical for the given plant. Sensitivity analyses on the economic evaluation criteria have demonstrated that the results obtained are robust against uncertainties in influent wastewater characteristics...

In situ upgrading of heavy oil under steam injection with tetralin and catalyst

Energy Technology Data Exchange (ETDEWEB)

Mohammad, A.A. [Texas A and M Univ., College Station, TX (United States); Mamora, D.D. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Texas A and M Univ., College Station, TX (United States)

2008-10-15

Steam injection has become the most successful thermal recovery method for heavy oil production. Heavy oil refineries use upgrading processes to improve oil quality. They generally involve the use of catalysts that are used to remove heavy metals, sulfur and nitrogen, or used in hydro-treating and hydro-cracking. In-situ upgrading is thought to have advantages over conventional surface upgrading technology. Experiments were performed to verify the feasibility of in-situ upgrading of heavy crude oil. A hydrogen donor called tetralin was used along with an organometallic catalyst, at steam injection temperatures and pressures normally encountered in the field. Crude oil from the Jobo Oil Field, located in Venezuela was used. The paper described the experimental methodology with reference to the injection cell; fluid injection system; fluid production system; data measurement and recording system; and experimental procedure. It also discussed the extent of upgrading by comparing the properties of the original and produced oil. Oil properties that were measured and compared included hydrogen-to-carbon ratio; heavy metal content; viscosity; and API gravity. The paper also presented a comparison of oil recovery and fluid production between all cases. It was concluded that in the field, the reaction time was significantly longer than encountered in the experiments and may lead to further upgrading, assuming the catalyst could be dispersed in the formation. 10 refs., 1 tab., 9 figs.

10 MeV RF electron linac for industrial applications

International Nuclear Information System (INIS)

2017-01-01

Electron linacs have found numerous applications in the field of radiation processing on an industrial scale. High power RF electron linacs are commonly used for food irradiation, medical sterilization, cross-linking of polymers, etc. For this purpose, the 10 MeV RF linac has been indigenously designed, developed, commissioned and is being used regularly at 3 kW beam power. This paper gives a brief description of the linac and its utilization for various applications. Safety considerations and regulatory aspects of the linac are also discussed

Alignment and Field Error Tolerance in Linac4

CERN Document Server

Bellodi, G; Garcia Tudela, M; Hein, L; Lallement, J B; Lanzone, S; Lombardi, A M; Posocco, P; Sargsyan, E

2011-01-01

LINAC4 [1] is a linear accelerator for negative Hydrogen ions (H−), which will replace the 50 MeV proton LINAC (LINAC2) as linear injector for the CERN accelerators. The higher output energy (160 MeV) together with charge-exchange injection will allow increasing beam intensity in the following machines. LINAC4 is about 80 m long, normal-conducting, and will be housed in a tunnel 12 m below ground on the CERN Meyrin site. The location has been chosen to allow using LINAC4 as the first stage of acceleration for a Multi-MegaWatt superconducting LINAC (SPL [2]). A 60 m long transfer line brings the beam towards the present LINAC2-to-PS Booster transfer line, which is joined at the position of BHZ20. The new transfer line consists of 17 new quadrupoles, an RF cavity and 4 bending magnets to adjust both the direction and the level for injection into the PS Booster. End-to-end beam dynamics simulations have been carried out in parallel with the codes PATH [3] and TRACEWIN[4]. Following the definition of the layout...

Wire alignment system for ATF LINAC

International Nuclear Information System (INIS)

Hayano, H.; Takeda, S.; Matsumoto, H.; Matsui, T.

1994-01-01

A wire based alignment system is adopted to make less than 40μm precision alignment for injector linac of Accelerator Test Facility (ATF). The system consists of two stretched SUS wires, pickup coils and active mover stages. The position of pickup coils in a mount which will be installed into LINAC stages is set to the calculated wire position prior to installation. All of LINAC stages are then moved to keep the calculated position by the active mover. The test results of wire position detection in a long term are described. (author)

Operating experience with the ALS linac

International Nuclear Information System (INIS)

Selph, F.; Massoletti, D.

1991-05-01

The linac injector for the Advanced Light Source (ALS) at LBL was recently put into operation. Energy is 50 MeV, frequency 3 GHz. The electron gun delivers up to 6nC in a 3.0-ns bunch at 120 kV. A train of bunches is injected into a 1-Hz booster and accelerated to 1.5 GHz for storage ring injection. A magnetic analysis system is used for optimizing the linac. Measured beam properties from the gun and after acceleration in the linac are described. 9 refs., 3 figs

Application of RF Superconductivity to High-Current Linac

International Nuclear Information System (INIS)

Chan, K.C.D.

1998-01-01

In 1997, the authors initiated a development program in Los Alamos for high-current superconducting proton-linac technology to build prototypes components of this linac to demonstrate the feasibility. The authors are building 700-MHz niobium cavities with elliptical shapes, as well as power couplers to transfer high RF power to these cavities. The cavities and power couplers will be integrated in cryostats as linac cryomodules. In this paper, they describe the linac design and the status of the development program

Pipeline transportation of emerging partially upgraded bitumen

International Nuclear Information System (INIS)

Luhning, R.W.; Anand, A.; Blackmore, T.; Lawson, D.S.

2002-01-01

upgrading heavy oil, and the tank bottom recovery and remediation (TaBoRR) process, the value creation upgrading process, Genoil hydro-processor upgrading, Albian Muskeg River oil sands mining, Vapex Process for in situ upgrading, super critical partial oxidation (SUPOX), ionic liquid catalysts, biocatalyst upgrading, CAPRI in situ upgrading, the aquaconversion process, the ROSE process for partial upgrading, the Chattanooga process, the CANMET emulsion upgrading process, the UniPure sulphur removal and upgrading, and the Geotreater process. 40 refs., 14 tabs., 3 figs

Argonne superconducting heavy-ion linac

International Nuclear Information System (INIS)

Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

1976-01-01

A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2 0 K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (ΔE/E approximately equal to 2 x 10 -4 ) or very good time resolution

S-band linac-based X-ray source with {pi}/2-mode electron linac

Energy Technology Data Exchange (ETDEWEB)

Deshpande, Abhay, E-mail: abhay@post.kek.jp [Department of Accelerator Science, School of High Energy Accelerator Science, Graduate University for Advanced Studies, Shonan International Village, Hayama, Miura, Kanagawa 240-0193 (Japan); Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Araki, Sakae [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Dixit, Tanuja [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Fukuda, Masafumi [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Krishnan, R; Pethe, Sanjay [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Sakaue, Kazuyuki [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan); Terunuma, Nobuhiro; Urakawa, Junji [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Washio, Masakazu [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan)

2011-05-01

The activities with the compact X-ray source are attracting more attention, particularly for the applications of the source in medical fields. We propose the fabrication of a compact X-ray source using the SAMEER electron linear accelerator and the KEK laser undulator X-ray source (LUCX) technologies. The linac developed at SAMEER is a standing wave side-coupled S-band linac operating in the {pi}/2 mode. In the proposed system, a photocathode RF gun will inject bunches of electrons in the linac to accelerate and achieve a high-energy, low-emittance beam. This beam will then interact with the laser in the laser cavity to produce X-rays of a type well suited for various applications. The side-coupled structure will make the system more compact, and the {pi}/2 mode of operation will enable a high repetition rate operation, which will help to increase the X-ray yield.

Ferrite HOM Absorber for the RHIC ERL

Energy Technology Data Exchange (ETDEWEB)

Hahn,H.; Choi, E.M.; Hammons, L.

2008-10-01

A superconducting Energy Recovery Linac is under construction at Brookhaven National Laboratory to serve as test bed for RHIC upgrades. The damping of higher-order modes in the superconducting five-cell cavity for the Energy-Recovery linac at RHIC is performed exclusively by two ferrite absorbers. The ferrite properties have been measured in ferrite-loaded pill box cavities resulting in the permeability values given by a first-order Debye model for the tiled absorber structure and an equivalent permeability value for computer simulations with solid ring dampers. Measured and simulated results for the higher-order modes in the prototype copper cavity are discussed. First room-temperature measurements of the finished niobium cavity are presented which confirm the effective damping of higher-order modes in the ERL. by the ferrite absorbers.

First Linac4 DTL & CCDTL cavities installed in tunnel

CERN Multimedia

Katarina Anthony

2014-01-01

On 5 June, the first Drift Tube Linac (DTL) was successfully transported to its forever home in the Linac4 tunnel. Similarly, the first Cell-Coupled Drift Tube Linac (CCDTL) was installed on 6 June. These moves marked the end of years of design and manufacturing by Linac4 teams.   Although it may seem like a relatively routine transport operation, the DTL's move was a landmark event for the entire Linac4 collaboration. "Along with the first four Cell-Coupled DTL modules, which were installed on the following two working days, these are the first accelerating structures after front-end commissioning to be installed in the tunnel," says Frank Gerigk, who is responsible for all Linac4 accelerating structures. "It is a major milestone, because work on all these structures started well over a decade ago." The transport operation was also quite a victory for the Linac4 DTL team, whose journey to a complete DTL structure has been a bit of a wild ride. &qu...

Variable-energy drift-tube linacs

International Nuclear Information System (INIS)

Swenson, D.A.; Boyd, T.J. Jr.; Potter, J.M.; Stovall, J.E.

1982-01-01

Practical applications of ion linacs are more viable now than ever before because of the recent development of the radio-frequency quadrupole accelerating structure, as well as other technological advances developed under the Pion Generator for Medical Irradiations program. This report describes a practical technique for varying the energy of drift-tube linacs and thus further broadening the possibilities for linac applications. This technique involves using the post couplers (normally used to flatten and stabilize the electric fields) to create a step in the fields, thus terminating the acceleration process. In the examples given for a 70-MeV accelerator design, when using this technique the energy is continually variable down to 20 MeV, while maintaining a small energy spread

Report of the eRHIC Ring-Ring Working Group

Energy Technology Data Exchange (ETDEWEB)

Aschenauer, E. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brennan, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fedotov, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Palmer, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Parker, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Willeke, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-10-13

This report evaluates the ring-ring option for eRHIC as a lower risk alternative to the linac-ring option. The reduced risk goes along with a reduced initial luminosity performance. However, a luminosity upgrade path is kept open. This upgrade path consists of two branches, with the ultimate upgrade being either a ring-ring or a linac-ring scheme. The linac-ring upgrade could be almost identical to the proposed linac-ring scheme, which is based on an ERL in the RHIC tunnel. This linac-ring version has been studied in great detail over the past ten years, and its significant risks are known. On the other hand, no detailed work on an ultimate performance ring-ring scenario has been performed yet, other than the development of a consistent parameter set. Pursuing the ring-ring upgrade path introduces high risks and requires significant design work that is beyond the scope of this report.

All Digital IQ Servo-System for CERN Linacs

CERN Document Server

Broere, J; Garoby, R; Rohlev, A; Serrano, J

2004-01-01

A VME based control system has been developed and built at CERN for the servo loops regulating the field in linac accelerating structures. It is an all-digital system built on a single VME card, providing digital detection, processing, and modulation. It is foreseen to be used, in different versions, for the needs of both present and future CERN hadron linacs. The first application will be in the energy ramping RF chain of the CERN Heavy Ion Linac (linac 3). Design principle and the experimental results are described.

Linac design for the LCLS project at SLAC

International Nuclear Information System (INIS)

Bharadwaj, V.K.; Bane, K.; Clendenin, J.

1997-05-01

The Linac Coherent Light Source (LCLS) at SLAC is being designed to produce intense, coherent 0.15-nm x-rays. These x-rays will be produced by a single pass of a 15 GeV bunched electron beam through a long undulator. Nominally, the bunches have a charge of 1 nC, normalized transverse emittances of less than 1.5π mm-mr and an rms bunch length of 20 μm. The electron beam will be produced using the last third of the SLAC 3-km linac in a manner compatible with simultaneous operation of the remainder of the linac for PEP-II. The linac design necessary to produce an electron beam with the required brightness for LCLS is discussed, and the specific linac modifications are described

RF linacs for FELs

International Nuclear Information System (INIS)

Schwettman, H.A.

1992-01-01

There are twenty rf linac-driven Free Electron Lasers (FELs) existing or under construction throughout the world and proposals for several more. A number of these FELs have recently been established as facilities to produce coherent optical beams for materials and biomedical research. Both short pulse low duty factor and long pulse high duty factor linac-driven FELs will be discussed. Accelerator issues that influence the performance of an FEL as a scientific instrument will be indicated. (Author) 6 refs., 6 figs., 2 tabs

BNCT with linac, feasibility study

International Nuclear Information System (INIS)

Alfuraih, A.; Ma, A.; Spyrou, N.M.; Awotwi-Pratt, Joseph

2006-01-01

High energy photon beams from Medical Linear Accelerators (linacs) which are used in radiotherapy produce undesirable neutrons, beside the clinically useful electron and photon beams. Neutrons are produced from the photonuclear reaction (γ,n) of high energy photons with high Z-materials which compose the accelerator head. In this paper the possible use of these undesirable neutrons for BNCT is investigated, making use of high energy linacs already installed in hospitals, primarily for high energy electron and photon therapy and applying them in the context of BNCT. The photoneutron components emitted by the accelerator is the source for Monte Carlo simulations of the interactions that take place within the head of a voxel-based phantom. The neutron flux across the phantom head is calculated using different moderator arrangements and different techniques in the aim of increasing the thermal neutron flux at the targeted site. Also, we shall test different configurations of the linac head to maximize the exposure of high-Z materials to the photon beam, including the removal of the flattening filter, so as to boost the photoneutron production in the linac head. Experimental work will be conducted in hospitals to validate the Monte Carlo simulations. To make use of linacs for BNCT will be advantageous in the sense that the setting in a hospital department is much more acceptable by the public than a reactor installation. This will mean less complications regarding patient positioning and movement with respect to the beams, additional patient transportation and management will be more cost effective. (author)

Argonne superconducting heavy-ion linac

Energy Technology Data Exchange (ETDEWEB)

Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

1976-01-01

A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2/sup 0/K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (..delta..E/E approximately equal to 2 x 10/sup -4/) or very good time resolution (..delta.. t approximately equal to 30 psec).

New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac

International Nuclear Information System (INIS)

Ward, T.E.; Alessi, J.; Brennan, J.; Grand, P.; Lankshear, R.; Snead, C.L.; Tsoupas, N.; Zucker, M.

1988-01-01

The installation of a new beam chopper and radio-frequency quadrupole (RFQ) preinjector (750 keV) at the Brookhaven National Laboratory (BNL) 200-MeV Linac will enable single micropulse selection (pulse width 9 pμ pulse with dc-average beam currents of 50 nA-1 μA routinely available. The NTOF facilities consists of 30-100 meter flight paths at angles of 0, 12, 30, 45, 90, and 135/degree/. Lower energies of 93, 117, 139, 161, and 181 MeV are also available as well as polarized beams at much reduced intensities. The present paper describes the new facilities, and the capabilities of future improvements and upgrades, for use in the BNL intermediate energy (p,n) experimental program. 7 refs., 2 figs., 1 tab

NPL superconducting Linac control system

International Nuclear Information System (INIS)

Swanson, H.E.; Howe, M.A.; Jackson, L.W.; LaCroix, J.M.; Readdy, H.P.; Storm, D.W.; Van Houten, L.P.

1985-01-01

The control system for the NPL Linac is based on a Microvax II host computer connected in a star network with 9 satellite computers. These satellites use single board varsions of DEC's PDP 11 processor. The operator's console uses high performance graphics and touch screen technology to display the current linac status and as the means for interactively controlling the operation of the accelerator

First beam in Linac4 DTL

CERN Multimedia

Katarina Anthony

2014-01-01

Following the installation of the Linac4 Drift Tube Linac (DTL) earlier this summer (see here), the first DTL tank saw beams at 12 MeV on 5 August.   Transverse emittance measured at 12 MeV after the DTL tank1 using a temporary slit-and-grid emittance device. You never forget your first beam. That was especially true for the Linac4 DTL team, as it followed years of design, construction and vigorous testing. "We performed countless measurements of the geometry, vacuum and magnet polarisation of the DTL tanks while we were in the workshop," says Suitbert Ramberger, project engineer for the Linac4 DTL. "Add that preparation to the excellent RF conditioning that we carried out in the weeks before the beam tests and I was confident that the acceleration with beam would fully meet expectations!" Indeed it did. Beam commissioning tests ran until 21 August and found the DTL operating with nominal transmission. This successful run has confirmed the innovative design ...

Linac technology for free-electron lasers

International Nuclear Information System (INIS)

Cooper, R.K.; Morton, P.L.; Wilson, P.B.; Keefe, D.; Faltens, A.

1983-01-01

The purpose of this paper is to concentrate on the properties of high-energy electron linear accelerators for use in free-electron lasers operating principally in the Compton regime. To fix our focus somewhat, we shall consider electron energies in the 20- to 200-MeV range and consider requirements for high-power free-electron lasers operating in the 0.5- to 10-μm range. Preliminary remarks are made on high-power free-electron laser amplifiers and oscillators and some desirable characteristics of the linacs that deliver electron beams for these devices. Both the high peak-current requirements of the amplifier and the high pulse-repetition frequency requirements of the oscillator can be met by present-day linac technology, although not necessarily by the same machine. In this papers second and third section, the technology of two rather different types of linear accelerators, the rf linac and the induction linac, is reviewed. In conclusion, applications to the Free Electron Lasers are stated

Diagnostic expert system in the PF LINAC

International Nuclear Information System (INIS)

Abe, Isamu; Nakahara, Kazuo; Kitamura, Masaharu.

1992-01-01

A prototype diagnostic expert system (ES) was developed for the Photon Factory 2.5-GeV electron/positron LINAC injector system. The ES has been on-lined with the conventional linac computer network for receiving real data. This project was undertaken in an attempt to reduce the linac operator's mental workload, diagnosis duties, and to explore Artificial Intelligence (AI) technologies. The outlook for ES and its problems, and what has been achieved are outlined in this presentation. (author)

Measurements of longitudinal phase space in the SLC linac

International Nuclear Information System (INIS)

Bane, K.; Adolphsen, C.; Lavine, T.L.; Ross, M.; Seeman, J.; Thompson, K.

1990-05-01

In the Stanford Linear Collider the beam leaves a damping ring and then enters the Ring-to-Linac (RTL) transfer line. In the RTL it is compressed in length by a factor of 10 by means of an rf section, with which a longitudinally correlated energy variation is induced in the beam, and a following beam line which has non-zero momentum compaction. The compressed beam then enters the linac proper. In this paper we describe three measurements of longitudinal properties of the beam in the SLC linac. We present measurements of single bunch beam loading, of the energy spectrum at the end of the linac, and of the linac bunch length. Since the results of all three measurements depend on the beam's longitudinal charge distribution in the linac they, in turn, also depend on the bunch lengthening that occurs in the damping rings, as well as on the behavior of the compressor. The results of the first two measurements, in addition, depend critically on the strength of the longitudinal wakefields in the linac. The results of these three measurements are compared with simulations. For these calculations, at any given current, the potential well distortion in the damping ring is first computed. The compression process is then simulated to obtain the longitudinal charge distribution in the linac. For the first two measurements this distribution is then convolved with the calculated longitudinal wake function of the SLAC linac in order to obtain the induced voltage. Finally, the induced voltage is combined with the effect of the linac rf wave to give the final energy spectrum. 8 refs., 5 figs

Dispersion and betatron matching into the linac

International Nuclear Information System (INIS)

Decker, F.J.; Adolphsen, C.; Corbett, W.J.; Emma, P.; Hsu, I.; Moshammer, H.; Seeman, J.T.; Spence, W.L.

1991-05-01

In high energy linear colliders, the low emittance beam from a damping ring has to be preserved all the way to the linac, in the linac and to the interaction point. In particular, the Ring-To-Linac (RTL) section of the SLAC Linear Collider (SLC) should provide an exact betatron and dispersion match from the damping ring to the linac. A beam with a non-zero dispersion shows up immediately as an increased emittance, while with a betatron mismatch the beam filaments in the linac. Experimental tests and tuning procedures have shown that the linearized beta matching algorithms are insufficient if the actual transport line has some unknown errors not included in the model. Also, adjusting quadrupole strengths steers the beam if it is offset in the quadrupole magnets. These and other effects have lead to a lengthy tuning process, which in the end improves the matching, but is not optimal. Different ideas will be discussed which should improve this matching procedure and make it a more reliable, faster and simpler process. 5 refs., 2 figs

Oxygen ion source and RFQ for Linac 1

CERN Multimedia

Photographic Service

1986-01-01

As injector to the PS Booster, Linac 1 was replaced by Linac 2 in 1980. It continued to be used for the acceleration of oxygen and sulfur ions. In 1984, its Cockcroft-Walton preinjector was replaced by an RFQ. In the foreground at the right is the oxygen ion source. A 90 deg bending magnet selects O6+ ions which are preaccelerated in an RFQ and enter Linac 1, at the far left. In the background is the proton and negative hydrogen ion source, followed by the 520 keV RFQ-1 and a bending magnet towards the entrance of Linac 1.

Range of Possible Beam Current in Linac4

CERN Document Server

Lallement, J-B; CERN. Geneva. BE Department

2009-01-01

Linac4 is a new accelerator under construction at CERN. It is designed to accelerate H- ions to 160MeV, for injection into the existing Proton Synchrotron Booster (PSB). It is also the front-end of the SPL Linac, a high energy proton driver that will reach the energy of 5GeV. The Linac baseline design has been done for a nominal beam peak current of 70mA but it will certainly have to deal with different currents. 132 out of 155 quadrupoles in the Linac are permanent magnets, this choice of using PMQ having fixed gradient, mainly in the DTL and in the CCDTL may then entail issues concerning the beam transverse matching and quality from current different from the nominal one. In this paper, we present the beam dynamics performances in Linac4 obtained for different currents.

Control system for Fermilab's low temperature upgrade

International Nuclear Information System (INIS)

Norris, B.L.

1996-09-01

Fermilab recently upgraded the Tevatron Cryogenic Systems to allow for lower temperature operation. This Lower Temperature Upgrade grew out of a desire to increase the Colliding Beam Physics energy from 900 GeV to 1000 GeV. A key element in achieving this goal is the new cryogenic control system designed at Fermilab and installed in 24 satellite refrigerators and 8 compressor buildings. The cryogenic improvements and addition hardware like cold compressors exceeded the capability of the original distributed controls package. The new distributed controls package uses a Multibus II platform and Intel's 80386 microprocessor. Token Ring is used as the link to the systems 6 primary crate locations with Arcnet used as the connection to the systems numerous I/O crates. I/0 capabilities are double the capabilities of the original system. Software has also been upgraded with the introduction of more flexible control loop strategies and Finite State Machines used for automatic sequential control, like quench recovery or cold compressor pump down

Study on design of proton linacs

International Nuclear Information System (INIS)

Yu Qingchang

2000-01-01

Two important directions in the development of proton linacs are high-current proton linacs (mainly applied in nuclear power field) and compact proton linacs (for proton therapy). There are some common characteristics in them: (1) Employment of the novel accelerating structures, which are combination and evolution of the conventional ones; (2) Accelerating beam with small emittance; (3) Requirement for high reliability. The construction of the former is, however, much more difficult because it still needs low beam lose rate and as high power transformation efficiency as possible. Some important problems in the design of these accelerators are discussed and some schemes designed are presented

Recirculating Beam Breakup Study for the 12 GeV Upgrade at Jefferson Lab

International Nuclear Information System (INIS)

Shin, Ilkyoung; Satogata, Todd; Ahmed, Shahid; Bogacz, Slawomir; Stirbet, Mircea; Wang, Haipeng; Wang, Yan; Yunn, Byung; Bodenstein, Ryan

2012-01-01

Two new high gradient C100 cryomodules with a total of 16 new cavities were installed at the end of the CEBAF south linac during the 2011 summer shutdown as part of the 12-GeV upgrade project at Jefferson Lab. We surveyed the higher order modes (HOMs) of these cavities in the Jefferson Lab cryomodule test facility and CEBAF tunnel. We then studied recirculating beam breakup (BBU) in November 2011 to evaluate CEBAF low energy performance, measure transport optics, and evaluate BBU thresholds due to these HOMs. This paper discusses the experiment setup, cavity measurements, machine setup, optics measurements, and lower bounds on BBU thresholds by new cryomodules.

Recirculating Beam Breakup Study for the 12 GeV Upgrade at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Ilkyoung Shin, Todd Satogata, Shahid Ahmed, Slawomir Bogacz, Mircea Stirbet, Haipeng Wang, Yan Wang, Byung Yunn, Ryan Bodenstein

2012-07-01

Two new high gradient C100 cryomodules with a total of 16 new cavities were installed at the end of the CEBAF south linac during the 2011 summer shutdown as part of the 12-GeV upgrade project at Jefferson Lab. We surveyed the higher order modes (HOMs) of these cavities in the Jefferson Lab cryomodule test facility and CEBAF tunnel. We then studied recirculating beam breakup (BBU) in November 2011 to evaluate CEBAF low energy performance, measure transport optics, and evaluate BBU thresholds due to these HOMs. This paper discusses the experiment setup, cavity measurements, machine setup, optics measurements, and lower bounds on BBU thresholds by new cryomodules.

Crossbar H-mode drift-tube linac design with alternative phase focusing for muon linac

Science.gov (United States)

Otani, M.; Futatsukawa, K.; Hasegawa, K.; Kitamura, R.; Kondo, Y.; Kurennoy, S.

2017-07-01

We have developed a Crossbar H-mode (CH) drift-tube linac (DTL) design with an alternative phase focusing (APF) scheme for a muon linac, in order to measure the anomalous magnetic moment and electric dipole moment (EDM) of muons at the Japan Proton Accelerator Research Complex (J-PARC). The CH-DTL accelerates muons from β = v/c = 0.08 to 0.28 at an operational frequency of 324 MHz. The design and results are described in this paper.

Upgrade Uranium Recovery Project No. 34110: final safety analysis report

International Nuclear Information System (INIS)

1981-09-01

The accident analysis of the upgrade uranium recovery system indicated three potential hazards: (1) criticality, (2) toxic fumes from nitric acid solutions, and (3) release of toxic uranyl nitrate solutions. Any of these are capable of causing the death of one or more employees; therefore, they form the basis for the residual risks identified below. The analysis found no hazardous energies or substances capable of causing irreversible injury to, or the death of, any members of the public. The following residual risks will be controlled administratively by procedural constraints: An operator or maintenance error will cause 235 U to be transferred into an unsafe container and cause a criticality. An operator or maintenance error will cause containers of 235 U bearing material to be improperly spaced and cause a criticality. Extensive corrosion will cause a hole to form in a calciner tube, the corrosion will go undetected, and a criticality will result, and a loss of system and/or building solution containment will occur concurrent with a drain being open resulting in a criticality and/or release of toxic material. Additional residual risks that have a small probability are that an earthquake or tornado will affect the building, alter the system geometry, and initiate a criticality; that the compressed-gas (nitrogen) cylinder valve will be sheared off, become airborne, and alter the system geometry; and that loss of system and/or building solution containment may occur concurrently with fire sprinkler system actuation causing a criticality and/or release of toxic material. The following residual risks will be addressed in the Safety Study of the existing X-705 Building: that a spill of raffinate highly contaminated with 99 Tc will occur due to operator error or incorrect lab analysis and that a gaseous or liquid effluent release of small amounts of transuranic elements will occur

A SUPER-CONDUCTING LINAC DRIVER FOR THE HFBR.

Energy Technology Data Exchange (ETDEWEB)

Alessi, J.; Raparia, D.; Ruggiero, A.G.

2000-08-21

This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a driver for the High-Flux Breeder Reactor (HFBR) at Brookhaven National Laboratory (BNL). The Linac operates in Continuous Wave (CW) mode to produce an average 10 MW of beam power. The Linac beam energy is 1.0 GeV. The average proton beam intensity in exit is 10 mA.

SLAC Linac Preparations for FACET

International Nuclear Information System (INIS)

Erickson, Roger

2011-01-01

The SLAC 3km linear electron accelerator has been cut at the two-thirds point to provide beams to two independent programs. The last third provides the electron beam for the Linac Coherent Light Source (LCLS), leaving the first two-thirds available for FACET, the new experimental facility for accelerator science and test beams. In this paper, we describe this separation and projects to prepare the linac for the FACET experimental program.

Radioisotope production linac

International Nuclear Information System (INIS)

Stovall, J.E.; Hansborough, L.D.; O'Brien, H.A.

1981-01-01

A 70-MeV proton beam would open a new family of medical radioisotopes (including the important 123 I) to wide application. A 70-MeV, 500-μA linac is described, based on recent innovations in accelerator technology. It would be 27.3 m long, cost approx. $6 million, and the cost of power deposited in the radioisotope-production target is comparable to existing cyclotrons. By operating the rf-power system to its full capability, the same accelerator is capable of producing a 1140-μA beam, and the cost per beam watt on the target is less than half that of comparable cyclotrons. The technology to build such a linac is in a mature stage of developmnt, ready for use by industry

Beam dynamics studies of the ISOLDE post-accelerator for the high intensity and energy upgrade

CERN Document Server

Fraser, M A

2012-01-01

The High Intensity and Energy (HIE) project represents a major upgrade of the ISOLDE (On-Line Isotope Mass Separator) nuclear facility at CERN with a mandate to significantly increase the energy, intensity and quality of the radioactive nuclear beams provided to the European nuclear physics community for research at the forefront of topics such as nuclear structure physics and nuclear astrophysics. The HIE-ISOLDE project focuses on the upgrade of the existing Radioactive ion beam EXperiment (REX) post-accelerator with the addition of a 40MVsuperconducting linac comprising 32 niobium sputter-coated copper quarter-wave cavities operating at 101.28 MHz and at an accelerating gradient close to 6 MV/m. The energy of post-accelerated radioactive nuclear beams will be increased from the present ceiling of 3 MeV/u to over 10 MeV/u, with full variability in energy, and will permit, amongst others, Coulomb interaction and few-nucleon transfer reactions to be carried out on the full inventory of radionuclides available ...

Beam Dynamics Studies of the ISOLDE Post-accelerator for the High Intensity and Energy Upgrade

CERN Document Server

Fraser, Matthew Alexander; Pasini, M

2012-01-01

The High Intensity and Energy (HIE) project represents a major upgrade of the ISOLDE (On-Line Isotope Mass Separator) nuclear facility at CERN with a mandate to significantly increase the energy, intensity and quality of the radioactive nuclear beams provided to the European nuclear physics community for research at the forefront of topics such as nuclear structure physics and nuclear astrophysics. The HIE-ISOLDE project focuses on the upgrade of the existing Radioactive ion beam EXperiment (REX) post-accelerator with the addition of a 40MVsuperconducting linac comprising 32 niobium sputter-coated copper quarter-wave cavities operating at 101.28 MHz and at an accelerating gradient close to 6 MV/m. The energy of post-accelerated radioactive nuclear beams will be increased from the present ceiling of 3 MeV/u to over 10 MeV/u, with full variability in energy, and will permit, amongst others, Coulomb interaction and few-nucleon transfer reactions to be carried out on the full inventory of radionuclides available ...

Operational experience with the CERN hadron linacs

International Nuclear Information System (INIS)

Charmot, H.; Dutriat, C.; Hill, C.E.; Langbein, K.; Lombardi, A.M.; O'Neil, M.; Tanke, E.; Vretenar, M.

1996-01-01

The present CERN proton linac (Linac2) was commissioned in 1978 and since that date has been the primary source of protons to the CERN accelerator complex. During the past 18 years, the machine has had a very good reliability record in spite of the demands made upon it. Modifications have been made with the view of maintaining this reliability with reduced resources and new requirements from the users. Further demands will be made in the future for LHC operation. In 1994, a new linac for heavy ion production was put into service replacing the original CERN proton linac. As this machine was built within an international collaboration, operation had to take into account the novelty of the techniques used and the variety of equipment supplied by outside collaborators. Even so, the new machine has also had very good reliability. (author)

Superconducting LINAC booster for the Mumbai pelletron

Indian Academy of Sciences (India)

LINAC), to boost the energy of heavy ion beams from the 14UD Pelletron accelerator, at Tata Institute of Fundamental Research, Mumbai. The accelerating structures in the LINAC are quarter wave resonators (QWR) coated with lead which is ...

The Pre-Injector Linac for the Diamond Light Source

CERN Document Server

Christou, C

2004-01-01

The Diamond Light Source is a new medium-energy high brightness synchrotron light facility which is under construction on the Rutherford Appleton Laboratory site in the U.K. The accelerator facility can be divided into three major components; a 3 GeV 561 m circumference storage ring, a full-energy booster synchrotron and a 100 MeV pre-injector linac. This paper describes the linac design and plans for operation. The linac is supplied by ACCEL Instruments GmbH under a turn-key contract, with Diamond Light Source Ltd. providing linac beam diagnostics, control system hardware and standard vacuum components. Commissioning of the linac will take place in early 2005 and user operation of the facility will commence in 2007.

Photon and photoneutron spectra produced in radiotherapy Linacs

International Nuclear Information System (INIS)

Vega C, H. R.; Martinez O, S. A.; Benites R, J. L.; Lallena, A. M.

2011-10-01

A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10 -6 and 1 MeV. Neutron and Bremsstrahlung spectra show the same features regardless of the linac voltage. The amount of photons and neutrons produced by the 15 MV linac is smaller than that found for the 18 MV linac. As expected, Bremsstrahlung spectra ends according to the voltage used to accelerate the electrons. (Author)

Photon and photoneutron spectra produced in radiotherapy Linacs

Energy Technology Data Exchange (ETDEWEB)

Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Martinez O, S. A. [Universidad Pedagogica y Tecnologica de Colombia, Grupo de Fisica Nuclear Aplicada y Simulacion, Av. Central del Norte Km. 1, Via Paipa Tunja, Boyaca (Colombia); Benites R, J. L. [Universidad Autonoma de Nayarit, Postgrado CBAP, Carretera Tepic Compostela Km. 9, Xalisco, Nayarit (Mexico); Lallena, A. M., E-mail: fermineutron@yahoo.com [Universida de Granada, Departamento de Fisica Atomica, Molecular y Nuclear, E-18071 Granada (Spain)

2011-10-15

A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10{sup -6} and 1 MeV. Neutron and Bremsstrahlung spectra show the same features regardless of the linac voltage. The amount of photons and neutrons produced by the 15 MV linac is smaller than that found for the 18 MV linac. As expected, Bremsstrahlung spectra ends according to the voltage used to accelerate the electrons. (Author)

Accelerator study note: An attempt of 1 GeV linac

International Nuclear Information System (INIS)

Kato, Takao.

1987-01-01

A hypothetical 1 GeV linac is described, including its structure (which includes an ion source, radio frequency quadrupole linac, drift type linac, and coupled cavity linac), criteria for optimized design, cost optimization, frequency dependability of high frequency electric power loss, tuning during operation, the general rf system, computer codes and example calculations, beam dynamics simulation, and reduction of energy spread through the use of a debuncher

Comparison of LINAC-4 Designs

CERN Document Server

Crandall, K; Sargsyan, E; Lallement, J-B; CERN. Geneva. BE Department

2009-01-01

We have studied the expected performance of two drift tube linac (DTL) designs proposed for LINAC-4. The two designs use the same cell geometries but are characterized by different phase (φs) and accelerating field (E0) distributions. In addition we have investigated the expected performance of 3 different quadrupole focusing schemes in each design. The expected performance of these 6 variants is compared with respect to their stability and risk of beam loss with alignment errors.

Study of characteristics of linac with TWRR

International Nuclear Information System (INIS)

Wang, Y.L.; Toyama, S.; Emoto, T.; Nomura, M.; Takahashi, N.; Oshita, H.; Hirano, K.; Sato, I.

1994-01-01

High power electron linac which is developed by PNC is an electron linac with the TWRR (Traveling Wave Resonant Ring). Some phenomena occurred on our high power test are mentioned. Some important characteristics such as stability and phase characteristic are discussed. (author)

Autopilot regulation for the Linac4 H- ion source

Science.gov (United States)

Voulgarakis, G.; Lettry, J.; Mattei, S.; Lefort, B.; Costa, V. J. Correia

2017-08-01

Linac4 is a 160 MeV H- linear accelerator part of the upgrade of the LHC injector chain. Its cesiated surface H- source is designed to provide a beam intensity of 40-50mA. It is operated with periodical Cs-injection at typically 30 days intervals [1] and this implies that the beam parameters will slowly evolve during operation. Autopilot is a control software package extending CERN developed Inspector framework. The aim of Autopilot is to automatize the mandatory optimization and cesiation processes and to derive performance indicators, thus keeping human intervention minimal. Autopilot has been developed by capitalizing on the experience from manually operating the source. It comprises various algorithms running in real-time, which have been devised to: • Optimize the ion source performance by regulation of H2 injection, RF power and frequency. • Describe the performance of the source with performance indicators, which can be easily understood by operators. • Identify failures, try to recover the nominal operation and send warning in case of deviation from nominal operation. • Make the performance indicators remotely available through Web pages.Autopilot is at the same level of hierarchy as an operator, in the CERN infrastructure. This allows the combination of all ion source devices, providing the required flexibility. Autopilot is executed in a dedicated server, ensuring unique and centralized control, yet allowing multiple operators to interact at runtime, always coordinating between them. Autopilot aims at flexibility, adaptability, portability and scalability, and can be extended to other components of CERN's accelerators. In this paper, a detailed description of the Autopilot algorithms is presented, along with first results of operating the Linac4 H- Ion Source with Autopilot.

The superconducting linac booster at the ANU

International Nuclear Information System (INIS)

Weisser, D.C.

1995-02-01

This report outlines the progress of the installation of the superconducting Linac booster at the Australian National University. The Linac is based upon four modules, three of which contain three split-loop resonators. The fourth cryostat was intended to be a superbuncher and so houses only one resonator. The first stage of Linac operation will employ only three modules with 2 MV/m from each resonator. It is expected that the implementation of all nine modules, in subsequent stages, would boost beams by 18 MV/q. The project has fostered productive international collaboration between UK and Australian scientists. 1 tab., 6 figs

Neutron and photon spectra in LINACs

International Nuclear Information System (INIS)

Vega-Carrillo, H.R.; Martínez-Ovalle, S.A.; Lallena, A.M.; Mercado, G.A.; Benites-Rengifo, J.L.

2012-01-01

A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10 –6 and 1 MeV. Neutron and the Bremsstrahlung spectra show the same features regardless of the linac voltage. - Highlights: ► With MCNPX code realistic models of two LINACs were built. ► Photon and neutron spectra below the flattening filter and at the isocenter were calculated. ► Neutron spectrum at the flattening filter was compared against the Tosi et al. source-term model. ► Tosi et al. model underestimates the neutron contribution below 1 MeV. ► Photon spectra look alike to those published in literature.

Control system for Fermilab`s low temperature upgrade

Energy Technology Data Exchange (ETDEWEB)

Norris, B.L.

1996-09-01

Fermilab recently upgraded the Tevatron Cryogenic Systems to allow for lower temperature operation. This Lower Temperature Upgrade grew out of a desire to increase the Colliding Beam Physics energy from 900 GeV to 1000 GeV. A key element in achieving this goal is the new cryogenic control system designed at Fermilab and installed in 24 satellite refrigerators and 8 compressor buildings. The cryogenic improvements and addition hardware like cold compressors exceeded the capability of the original distributed controls package. The new distributed controls package uses a Multibus II platform and Intel`s 80386 microprocessor. Token Ring is used as the link to the systems 6 primary crate locations with Arcnet used as the connection to the systems numerous I/O crates. I/0 capabilities are double the capabilities of the original system. Software has also been upgraded with the introduction of more flexible control loop strategies and Finite State Machines used for automatic sequential control, like quench recovery or cold compressor pump down.

Present status of the ETL LINAC facility

International Nuclear Information System (INIS)

Suzuki, Ryoichi; Mikado, Tomohisa; Ohgaki, Hideaki

1993-01-01

The ETL LINAC has been operated for the beam injection to the storage rings NIJI-II, III, IV, and TERAS, and for the generation of an intense slow positron beam. The status of the ETL LINAC on the operations, the maintenances, and the improvements is described. (author)

Fermilab 200 MeV linac control system hardware

Energy Technology Data Exchange (ETDEWEB)

Shea, M.F.

1984-01-01

This report is a description of the present Linac distributed control system that replaces the original Xerox computer and interface electronics with a network of 68000-based stations. In addition to replacing the obsolete Xerox equipment, goals set for the new system were to retain the fast response and interactive nature of the original system, to improve reliability, to ease maintenance, and to provide 15 Hz monitoring of all Linac parameters. Our previous experience with microcomputer installations showed that small, stand-alone control systems are rather straightforward to implement and have been proven to be reliable in operation, even in the severe environment of the 750-keV preaccelerator. The overall design of the Linac system incorporates the concept of many relatively small, stand-alone control systems networked together using an intercomputer communication network. Each station retains its local control system character but takes advantage of the network to allow an operator to interact with the entire Linac from any local console. At the same time, a link to the central computer system allows Host computers to also access parameters in the Linac.

Fermilab 200 MeV linac control system hardware

International Nuclear Information System (INIS)

Shea, M.F.

1984-01-01

This report is a description of the present Linac distributed control system that replaces the original Xerox computer and interface electronics with a network of 68000-based stations. In addition to replacing the obsolete Xerox equipment, goals set for the new system were to retain the fast response and interactive nature of the original system, to improve reliability, to ease maintenance, and to provide 15 Hz monitoring of all Linac parameters. Our previous experience with microcomputer installations showed that small, stand-alone control systems are rather straightforward to implement and have been proven to be reliable in operation, even in the severe environment of the 750-keV preaccelerator. The overall design of the Linac system incorporates the concept of many relatively small, stand-alone control systems networked together using an intercomputer communication network. Each station retains its local control system character but takes advantage of the network to allow an operator to interact with the entire Linac from any local console. At the same time, a link to the central computer system allows Host computers to also access parameters in the Linac

Error studies for SNS Linac. Part 1: Transverse errors

International Nuclear Information System (INIS)

Crandall, K.R.

1998-01-01

The SNS linac consist of a radio-frequency quadrupole (RFQ), a drift-tube linac (DTL), a coupled-cavity drift-tube linac (CCDTL) and a coupled-cavity linac (CCL). The RFQ and DTL are operated at 402.5 MHz; the CCDTL and CCL are operated at 805 MHz. Between the RFQ and DTL is a medium-energy beam-transport system (MEBT). This error study is concerned with the DTL, CCDTL and CCL, and each will be analyzed separately. In fact, the CCL is divided into two sections, and each of these will be analyzed separately. The types of errors considered here are those that affect the transverse characteristics of the beam. The errors that cause the beam center to be displaced from the linac axis are quad displacements and quad tilts. The errors that cause mismatches are quad gradient errors and quad rotations (roll)

The invention that is shaping Linac4

CERN Multimedia

CERN Bulletin

2010-01-01

Accelerator experts are no strangers to innovative optimizations of existing techniques and to the development of novel solutions. Sometimes, they even come up with ideas that have the potential to revolutionize the field. This is the case with the Tolerance Aligned Cantilever Mounting (TACM) system, a completely new way of supporting the drift tubes, one of the core elements of linear accelerators. The new, patent-pending technique will be implemented at Linac4.   Drift tubes in a prototype for Linac4, assembled using the new TACM technology. “Assemble and adjust” – that was the technique used to build drift-tube linacs before the arrival of the TACM. Now, the inventors’ motto has become ‘adjust and assemble’. The inversion of these two words represents a real revolution for people working in the field. “The drift tubes are a critical element of Linac4 and they have to satisfy several requirements: they have to be mechanically ...

Beam dynamics of alternating-phase-focused linac

CERN Document Server

Iwata, Y; Kapin, V

2004-01-01

A simple method to find an array of synchronous phases for alternating-phase-focused (APF) linacs is presented. The phase array is described with a smooth function having free parameters. With a set of the parameters, a simulation on the beam dynamics was made and distributions of the six-dimensional phase spaces were calculated for each set of the parameters. The parameters were varied, and numbers of the simulations have been performed. An optimum set of the parameters were determined so that the simulations of the beam dynamics yield large acceptances and small emittances of the extracted beams. Since the APF linac can provide both axial and radial stability of beams just with the rf acceleration-field, no additional focusing element inside of drift tubes are necessary. Comparing with conventional linacs having focusing elements, it has advantage in construction and operation costs as well as its acceleration rate. Therefore, the APF linacs would be suited for an injector of medical synchrotrons. A practic...

Some aspects of linacs as applied to the ISL benchmark facility

International Nuclear Information System (INIS)

Shepard, K.W.

1992-01-01

This paper considers several aspects of using linacs in a radioactive beam facility in terms of the Isospin Laboratory (ISL) Benchmark Facility (BMF) plan, described in the 1991 white paper for a possible radioactive-beam laboratory. The intention is not to review comprehensively the application of linacs to an ISL facility, but to compare in outline form several linac options for such a facility. Particular emphasis is given to the use of superconducting rf technology for the secondary beam accelerator. In what follows, first a possible normally-conducting light-ion linac for a primary beam accelerator is briefly outlined. Then the performance and cost of two options for a secondary beam accelerator are compared: a recent design for a normal-conducting cw linac, and an ATLAS-type superconducting linac. Finally, some of the problems which may be encountered at the entrance of a secondary beam linac are discussed

Challenges of the ILC Main Linac

International Nuclear Information System (INIS)

Ross, Marc

2007-01-01

With the completion of the ILC Reference Design Report (RDR), we begin the next phase of the project - development of the Engineering Design. Our strategy and priorities come from the identification, contained in the RDR, of scientific and engineering challenges of the ILC. First among these is the cost of the main linac which, including the associated earthworks and cooling/power systems, amounts to 60% of the ILC total cost. Next is the challenge to reach the highest practical gradient since this R and D has the largest cost leverage of any of the ongoing programs. Finally, we have to understand the beam dynamics and beam tuning processes in the main linac, as we will not have the opportunity to do full (or even large) scale tests of these before the linac is constructed.

A heavy ion linac complex for RI beams

International Nuclear Information System (INIS)

Arai, Shigeaki

1995-01-01

A heavy ion linac complex for RI-beams has been under construction since fiscal year 1992 at INS. The linac complex comprises following accelerating structures: a 25.5-MHz split coaxial RFQ (SCRFQ), a 51-MHz interdigital-H (IH) linac, and a 25.5-MHz rebuncher cavity. The SCRFQ with modulated vanes accelerates ions with a charge-to-mass ratio (q/A) greater than 1/30 from 2 to 170 keV/u. The IH linac comprises four cavities and three magnetic quadrupole triplets placed between cavities, accelerates ions with q/A≥1/10, and varies the output energy continuously in the range 0.17 ∼1.05 MeV/u. The rebuncher cavity with six accelerating gaps is a double coaxial λ/4 resonator, and the total accelerating voltage is 200 kV. (author)

LINAC4, A New $H^{-}$ Linear Injector at CERN

CERN Document Server

Garoby, R; Hanke, K; Lombardi, A M; Rossi, C; Vretenar, M

2004-01-01

Linac2, the present injector of the CERN PS Booster, limits the performance of the proton accelerator complex because of its low output energy (50 MeV). To remove this bottleneck, a higher energy linac is proposed (called â€ﾜLinac4†) which will double the brightness and the intensity of the beam delivered by the PSB and ensure the â€ﾜultimate” beam is available for LHC. Linac4 will deliver H- ions at a kinetic energy of 160 MeV. It is designed to be usable as the front-end of a future multi-GeV multi-MW linear accelerator, the â€ﾜSuperconducting Proton Linac” (SPL). R&D for Linac4 is now actively taking place with the support of the European Union through the Joint Research Activity HIPPI (â€ﾜHigh Intensity Pulsed Proton Injectors”), and of three ISTC projects involving three major Russian laboratories (BINP, IHEP and ITEP) and two nuclear centres (VNIIEF and VNIITF). The design of this new accelerator and the on-going developments are described.

Status and plans for Linac4 installation and commissioning

CERN Document Server

Vretenar, M; Arnaudon, L; Baudrenghien, P; Bellodi, G; Broere, J; Brunner, O; Comblin, J F; Coupard, J; Dimov, V A; Fuchs, J F; Funken, A; Gerigk, F; Granemann Souza, E; Hanke, K; Hansen, J; Yarmohammadi Satri, M; Kozsar, I; Lallement, J B; Lenardon, F; Lettry, J; Lombardi, A M; Maglioni, C; Midtun, O; Mikulec, B; Nisbet, D; Paoluzzi, M; Raich, U; Ramberger, S; Roncarolo, F; Rossi, C; Sanchez Alvarez, J L; Scrivens, R; Tan, J; Valerio-Lizarraga, C A; Vollaire, J; Wegner, R; Weisz, S; Zocca, F

2014-01-01

Linac4 is a normal conducting 160 MeV Hˉ linear accelerator presently being installed and progressively commissioned at CERN. It will replace the ageing 50 MeV Linac2 as injector of the PS Booster (PSB), increasing at the same time its brightness by a factor of two thanks to the higher injection energy. This will be the first step of a program to increase the beam brightness in the LHC injectors for the needs of the High-Luminosity LHC project. After a series of beam measurements on a dedicated test stand the 3 MeV Linac4 front-end, including ion source, RFQ and a beam chopping line, has been recommissioned at its final position in the Linac4 tunnel. Commissioning of the following section, the Drift Tube Linac, is starting. Beam commissioning will take place in steps of increasing energy, to reach the final 160 MeV in 2015. An extended beam measurement phase including testing of stripping equipment for the PSB and a year-long test run to assess and improve Linac4 reliability will take place in 2016, prior to...

Design and Development of RF Structures for Linac4

CERN Document Server

Vretenar, M; Gerigk, F; Pasini, M; Wegner, R

2006-01-01

Linac4 is a new 160 MeV H− linac proposed at CERN to replace the 50 MeV Linac2 as injector to the PS Booster, with the goal of doubling its brightness and intensity. The present design foresees after RFQ and chopping line a sequence of three accelerating structures: a Drift Tube Linac (DTL) from 3 to 40 MeV, a Cell-Coupled DTL (CCDTL) to 90 MeV and a Side Coupled Linac (SCL) up to the final energy. The DTL and CCDTL operate at 352 MHz, while in the SCL the frequency is doubled to 704 MHz. Although the injection in the PS Booster requires only a low duty cycle, the accelerating structures are designed to operate at the high duty cycle required by a possible future extension to a high-power linac driver for a neutrino facility. This paper presents the different accelerating structures, underlining the progress in the design of critical resonator elements, like post-couplers in the DTL, coupling slots in the CCDTL and bridge couplers for the SCL. Prototyping progress for the different structures is reported...

Linac4: the final assembly stage is under way

CERN Multimedia

CERN Bulletin

2013-01-01

The Linac4 radiofrequency quadrupole (RFQ) module was installed at the accelerator test-stand in Building 152 last August. After an assembly phase and tests that concluded last March with the acceleration of a hydrogen beam to 3 MeV, the module has just been permanently installed in the new Linac4 tunnel (Building 400). The installation of the MEBT (Medium Energy Beam Transport) will begin shortly, followed by the start of the first Linac4 commissioning phase.     To find out more about the Linac4 RFQ module, read the previous Bulletin articles published in Nos. 21-22/2010 and 35-36/2012.

UPGRADES

CERN Multimedia

J. Spalding and D. Contardo

2012-01-01

  The CMS Upgrade Programme consists of four classes of projects: (a) Detector and Systems upgrades which are ongoing and largely (though not entirely) target LS1. (b) Full system upgrades for three projects that are preparing TDRs: Pixels, HCAL and L1 Trigger. The projects target completion by LS2. (c) Infrastructure consolidation and upgrades to improve operational robustness and to support the above projects. (d) Phase 2 replacement of the Tracker and major upgrades of the Trigger and Forward Detectors. For (a) and (c), detailed costing exists and is being integrated into a common reporting system. The schedule milestones for each project will be linked into the overall schedule planning for LS1. For the three TDR projects, the designs have progressed significantly since the Technical Proposal in 2010. Updated detailed cost estimates and schedules will be prepared with the TDRs to form the basis for tracking the projects through completion. To plan the upgrades and the supporting simulati...

Brookhaven Linac Isotope Producer

Data.gov (United States)

Federal Laboratory Consortium — The Brookhaven Linac Isoptope Producer (BLIP)—positioned at the forefront of research into radioisotopes used in cancer treatment and diagnosis—produces commercially...

RF linac designs with beams in thermal equilibrium

International Nuclear Information System (INIS)

Reiser, M.; Brown, N.

1996-01-01

Beams in conventional radio-frequency linear accelerators (rf linacs) usually have a transverse temperature which is much larger than the longitudinal temperature. With high currents, space charge forces couple the transverse and longitudinal particle motions, driving the beam toward thermal equilibrium, which leads to emittance growth and halo formation. A design strategy is proposed in which the beam has equal transverse and longitudinal temperatures through the entire linac, avoiding these undesirable effects. For such equipartitioned linac beams, simple analytical relationships can be derived for the bunch size, tune depression, and other parameters as a function of beam intensity, emittance, and external focusing. These relations were used to develop three conceptual designs for a 938 MeV, 100 mA proton linac with different tune depressions, which are presented in this paper. copyright 1996 American Institute of Physics

Heavy ion induction linacs for fusion

International Nuclear Information System (INIS)

Bangerter, R.O.; Ho, D.D.M.

1991-01-01

In 1976 Denis Keefe proposed the heavy ion induction linac as a driver for inertial confinement fusion (ICF) power plants. Subsequent research has established that heavy ion fusion (HIF) is potentially an attractive energy source and has identified the issues that must be resolved to make HIF a reality. The principal accelerator issues are achieving adequately low transverse and longitudinal emittance and acceptable cost. Results from the single and multiple beam experiments at LBL on transverse emittance are encouraging. A predicted high current longitudinal instability that can affect longitudinal emittance is currently being studied. This paper presents an overview of economics and ICF target requirements and their relationship to accelerator design. It also presents a summary of the status of heavy ion induction linac research. It concludes with a discussion of research plans, including plans for the proposed Induction Linac Systems Experiments (ILSE)

Development of the Medium Energy Linac Systems

International Nuclear Information System (INIS)

Jang, Ji Ho; Kwon, Hyeok Jung; Kim, Dae Il; Kim, Han Sung; Park, Bum Sik; Seol, Kyung Tae; Song, Young Gi; Yun, Sang Pil; Cho, Yong Sub; Hong, In Seok

2008-05-01

The main purpose of this project is developing 100-MeV proton linear accelerator (linac) for proton engineering frontier project (PEFP). In the first phase of the PEFP, the development of the 20-MeV linac has successfully finished. Hence the work scope of this project is designing the linac to accelerate proton beams from 20-MeV up to 100-MeV, fabricating the linac up to 45 MeV, fabricating one set of the medium energy beam transport (MEBT) tank, and developing the low level radio frequency (LLRF) system and the control system. The basic role of the new proton accelerator is accelerating 20-mA proton beams from 20 MeV up to 100 MeV. The first step of the design procedure is optimizing and determining the accelerator parameters. The beam loss is also main concern in the design stage. The drift tube (DT) and the quadrupole magnets are designed to be optimized to the new linac design. The other purpose is confirming the new design by fabricating and tuning the drift tube linac (DTL). The 20MeV proton beam divided into two directions. One is supplying the beams to user group by turning on the 45-degree bending magnet. The other is guided into the 100-MeV DTL by tuning off the dipole magnet. That is why the PEFP MEBT located after 20-MeV DTL. The MEBT is realized as two small DTL tanks with three cells and a 45-degree bending magnet. The fabrication of one MEBT tank is another purpose of this project. The other purposes of this project is developing the LLRF system to control the RF signal and control system to monitor and control the vacuum system, magnet power supply, etc

Development of the High Energy Linac Systems

International Nuclear Information System (INIS)

Cho, Yong Sub; Kwon, Hyeok Jung; Kim, Han Sung; Chung, Byung Chul; Jang, Ji Ho; Gao, Changgi; Li, Yingmin; Sun, An; Tang, Yazhe; Zhang, Lipoing; Hwang, Yong Seok

2008-05-01

The main purpose of this project is studying the extension plan of the proton engineering frontier project (PEFP) 100-MeV Linac. It includes three categories. One is studying operation plan of the PEFP linac and its extended accelerators, and developing a distribution system of 100-MeV proton beams with a laser striping. Other is designing superconducting RF (SRF) modules and fabricating and testing a copper cavity model. The other is designing a rapid cycling synchrotron (RCS). The operation scheme of the PEFP linac is related to the optimization in the operation of the 100-MeV linac, 200-MeV SRF, and RCS. We studied several operational method to increase the validity of the accelerators. The beam distribution system has two roles. One is supplying proton beams of 100 MeV to the user group. The laser stripping of the negative hydrogen atoms is used in this case. The other beams are directed to the next high energy accelerators. This study contributes to increase the availability of the proton beams. The SRF is one of candidates to extend the PEFP linac system. Since the accelerating gradient of the SRF is much higher than the normal conducting accelerator, a lot of institutes over the world are developing the SRF structure. Main purposes are designing an SRF module, fabricating and testing an copper model which has similar material properties as Nb of the usual SRF cavity material. The RCS is a synchrotron whose injector is the PEFP 100-MeV linac. Main purposes are determining the lattice structure, studying the fast and slow extraction system, simulating beam behavior in the designed synchrotron. The RCS will be used as the spallation neutron source and tools in the basic and applied science including medical application

Computation of Normal Conducting and Superconducting Linear Accelerator (LINAC) Availabilities

International Nuclear Information System (INIS)

Haire, M.J.

2000-01-01

A brief study was conducted to roughly estimate the availability of a superconducting (SC) linear accelerator (LINAC) as compared to a normal conducting (NC) one. Potentially, SC radio frequency cavities have substantial reserve capability, which allows them to compensate for failed cavities, thus increasing the availability of the overall LINAC. In the initial SC design, there is a klystron and associated equipment (e.g., power supply) for every cavity of an SC LINAC. On the other hand, a single klystron may service eight cavities in the NC LINAC. This study modeled that portion of the Spallation Neutron Source LINAC (between 200 and 1,000 MeV) that is initially proposed for conversion from NC to SC technology. Equipment common to both designs was not evaluated. Tabular fault-tree calculations and computer-event-driven simulation (EDS) computer computations were performed. The estimated gain in availability when using the SC option ranges from 3 to 13% under certain equipment and conditions and spatial separation requirements. The availability of an NC LINAC is estimated to be 83%. Tabular fault-tree calculations and computer EDS modeling gave the same 83% answer to within one-tenth of a percent for the NC case. Tabular fault-tree calculations of the availability of the SC LINAC (where a klystron and associated equipment drive a single cavity) give 97%, whereas EDS computer calculations give 96%, a disagreement of only 1%. This result may be somewhat fortuitous because of limitations of tabular fault-tree calculations. For example, tabular fault-tree calculations can not handle spatial effects (separation distance between failures), equipment network configurations, and some failure combinations. EDS computer modeling of various equipment configurations were examined. When there is a klystron and associated equipment for every cavity and adjacent cavity, failure can be tolerated and the SC availability was estimated to be 96%. SC availability decreased as

Electro neutrons around a 12 MV Linac

International Nuclear Information System (INIS)

Vega C, H. R.; Perez L, L. H.

2012-10-01

Neutron contamination around Linacs for radiotherapy is a source of undesirable doses for the patient. The main source of these neutrons is the photonuclear reactions occurring in the Linac head and the patient body. Electrons also produce neutrons through (e, en) reactions. This reaction is known as electro disintegration and is carried out by the electron scattering that produce a virtual photon that is absorbed by the scattering nucleus producing the reaction e + A → (A-1) + n + e'. In this work the electron-neutron spectrum to 100 cm from the isocenter of a 12 MV Linac has been measured using a passive Bonner spheres spectrometer in a novel procedure named Planetary mode. (Author)

1170-MW(t) HTGR-PS/C plant application study report: tar sands oil recovery application

International Nuclear Information System (INIS)

Rao, R.; McMain, A.T. Jr.

1981-05-01

This report summarizes a study to apply an 1170-MW(t) high-temperature gas-cooled reactor - process steam/cogeneration (HTGR-PS/C) to tar sands oil recovery and upgrading. The raw product recovered from the sands is a heavy, sour bitumen; upgrading, which involves coking and hydrodesulfurization, produces a synthetic crude (refinable by current technology) and petroleum coke. Steam and electric power are required for the recovery and upgrading process. Proposed and commercial plants would purchase electric power from local utilities and obtain from boilers fired with coal and with by-product fuels produced by the upgrading. This study shows that an HTGR-PS/C represents a more economical source of steam and electric power

Improvements on monitor system in the KEK 2.5-GeV linac

International Nuclear Information System (INIS)

Shidara, T.; Oogoe, T.; Ogawa, Y.

1989-01-01

Improvements to the monitor system of the KEK 2.5-GeV linac have been undertaken. Energy analyzing stations were added to both the positron generator linac and the 2.5-GeV electron linac in order to realize easier checking of beam energy. Wall current monitors and profile monitors were added in the beam transport line between the positron generator linac and the 2.5-GeV electron linac in order to realize easier positron-beam transfer. As a result of the installation of an automatic beam-current-surveillance system and with other existing surveillance systems, more reliable and easier operation of the linac is expected. (author)

Upgrading low-boiling-fraction fast pyrolysis bio-oil using supercritical alcohol: Understanding alcohol participation, chemical composition, and energy efficiency

International Nuclear Information System (INIS)

Jo, Heuntae; Prajitno, Hermawan; Zeb, Hassan; Kim, Jaehoon

2017-01-01

Highlights: • Non-catalytic and non-hydrogen based bio-oil upgrading was conducted using scMeOH. • 16–40 wt% alcohols were consumed during the upgrading. • High bio-oil yield of 78.4 wt% and low TAN of 4.0 mg KOH/g were achieved. • Effect of supercritical alcohols, reaction times, temperature and bio-oil concentration was conducted. • scMeOH upgrading has good energy recovery (ER) and energy efficiency (EE) compared with scEtOH and scIPA. - Abstract: Herein, a supercritical methanol (scMeOH) route for efficient upgrading of the low-boiling fraction of fast pyrolysis bio-oil containing a large amount of low-molecular-weight acids and water was investigated. The effects of various reaction parameters, including the temperature, concentration, and time, were explored. The yield of bio-oil and the energy efficiency of the scMeOH upgrading process were determined based on the amount of methanol that participated in the reaction during upgrading and fractionation of the upgraded heavy-fraction bio-oils (UHBOs) and upgraded light-fraction bio-oils (ULBOs). Upgrading at 400 °C with 9.1 wt% bio-oil for 30 min generated a high bio-oil yield of 78.4 wt% with a low total acid number (TAN) of 4.0 mg-KOH/g-oil and a higher heating value of 29.9 MJ kg −1 . The energy recovery (ER) was 94–131% and the energy efficiency (EE) was in the range of 79–109% depending on the calorific values of the ULBOs. Compared with upgrading in supercritical ethanol and supercritical isopropanol, less alcohol participation, a lower TAN, and higher ER and EE were achieved with scMeOH upgrading. Plausible pathways for bio-oil upgrading in supercritical alcohols based on detailed compositional analysis of the UHBO, ULBO, and gaseous products were discussed.

UPGRADES

CERN Multimedia

J. Butler and J. Nash

2011-01-01

Recent progress on the CMS upgrades was summarised, in a workshop held at Fermilab between 7th and 10th November, attended by more than 150 people, many of whom came from Europe and Asia. Important goals of the workshop were to begin to formulate a schedule for the upgrades and to determine project interdependencies. Input was received from all the upgrade working groups and will be combined into a first-pass schedule over the next several weeks. In addition, technical progress on each of the major subtasks was presented and plans for the near-term future were established. Slides from the more than 100 talks are located at: https://indico.cern.ch/conferenceDisplay.py?confId=153564 In the opening plenary session, Frank Zimmermann, of the CERN Beams Department, gave his view of the LHC luminosity evolution. The luminosity will increase faster than we assumed in designing the upgrades. CMS will need to re-evaluate the current upgrade plans and revise them if necessary. CMS Upgrade Physics coordinator...

Application of superconductivity to intense proton linacs

International Nuclear Information System (INIS)

Heinrichs, H.

1996-01-01

Three examples of proposed superconducting linacs for intense particle beams are presented, and in two cases compared to normal conducting counterparts. Advantages and disadvantages of both types are discussed. Suggestions for future developments are presented. Finally a comparison of estimated operational costs of the normal and the superconducting linac for the ESS is given. (R.P.)

Physics design of APT linac with normal conducting rf cavities

International Nuclear Information System (INIS)

Nath, S.; Billen, J.H.; Stovall, J.E.; Takeda, Harunori; Young, L.M.

1996-01-01

The accelerator based production of tritium calls for a high-power, cw proton linac. Previous designs for such a linac use a radiofrequency quadrupole (RFQ), followed by a drift-tube linac (DTL) to an intermediate energy and a coupled-cavity linc (CCL) to the final energy. The Los Alamos design uses a high-energy (6.7 MeV) RFQ followed by the newly developed coupled-cavity drift-tube linac (CCDTL) and a CCL. This design accommodates external electromagnetic quadrupole lenses which provide a strong uniform focusing lattice from the end of the RFQ to the end of the CCL. The cell lengths in linacs of traditional design are typically graded as a function of particle velocity. By making groups of cells symmetric in both the CCDTL and CCL, the cavity design as well as mechanical design and fabrication is simplified without compromising the performance. At higher energies, there are some advantages of using superconducting rf cavities. Currently, such schemes are under vigorous study. This paper describes the linac design based on normal conducting cavities and presents simulation results

A novel electron gun for inline MRI-linac configurations

International Nuclear Information System (INIS)

Constantin, Dragoş E.; Fahrig, Rebecca; Holloway, Lois; Keall, Paul J.

2014-01-01

Purpose: This work introduces a new electron gun geometry capable of robust functioning in the presence of a high strength external magnetic field for axisymmetric magnetic resonance imaging (MRI)-linac configurations. This allows an inline MRI-linac to operate without the need to isolate the linear accelerator (linac) using a magnetic shield. This MRI-linac integration approach not only leaves the magnet homogeneity unchanged but also provides the linac flexibility to move along the magnet axis of symmetry if the source to target distance needs to be adjusted. Methods: Simple electron gun geometry modifications of a Varian 600C electron gun are considered and solved in the presence of an external magnetic field in order to determine a set of design principles for the new geometry. Based on these results, a new gun geometry is proposed and optimized in the fringe field of a 0.5 T open bore MRI magnet (GE Signa SP). A computer model for the 6 MeV Varian 600C linac is used to determine the capture efficiency of the new electron gun-linac system in the presence of the fringe field of the same MRI scanner. The behavior of the new electron gun plus the linac system is also studied in the fringe fields of two other magnets, a 1.0 T prototype open bore magnet and a 1.5 T GE Conquest scanner. Results: Simple geometrical modifications of the original electron gun geometry do not provide feasible solutions. However, these tests show that a smaller transverse cathode diameter with a flat surface and a slightly larger anode diameter could alleviate the current loss due to beam interactions with the anode in the presence of magnetic fields. Based on these findings, an initial geometry resembling a parallel plate capacitor with a hole in the anode is proposed. The optimization procedure finds a cathode-anode distance of 5 mm, a focusing electrode angle of 5°, and an anode drift tube length of 17.1 mm. Also, the linac can be displaced with ±15 cm along the axis of the 0.5 T

University of Washington superconducting booster linac

International Nuclear Information System (INIS)

Storm, D.W.; Amsbaugh, J.F.; Cramer, J.G.; Swanson, H.E.; Trainor, T.A.; Vandenbosch, R.; Weitkamp, W.G.; Will, D.I.

1985-01-01

We have begun construction of a superconducting linac designed to accelerate ions from protons through about mass 60. Injected by our 9 MV-terminal tandem van de Graaff accelerator, the linac is expected to double the proton energy and quadruple the energies of heavier ions. The resonators are lead plated copper quarter wave structures. The overall layout and expected performance of the accelerator will be presented, along with a brief status report. 3 refs., 3 figs

Beam dynamics design of the 211 MeV APT normal conducting linac

International Nuclear Information System (INIS)

Young, L.M.; Billen, J.H.; Takeda, H.; Wood, R.L.

1998-01-01

This paper describes the normal conducting linac design that is part of the Accelerator for Production of Tritium (APT) project. The new version of PARMILA designed this linac. This linac accepts the beam from the 6.7 MeV radio frequency quadrupole without a separate matching section. At about 10 MeV, it has a smooth transition in the length of period from 8βλ to 9βλ in quadrupole focusing lattice. This adjustment of the period was needed to provide sufficient space for the quadrupole focusing magnets and beam diagnostic equipment. The linac consists of the coupled cavity drift tube linac up to 97 MeV and coupled cavity linac above 97 MeV

A Pencil Beam for the Linac4 commissioning

CERN Document Server

Lallement, JB

2010-01-01

In order to characterize the different accelerating structures and transport lines of Linac4 and to proceed to its commissioning, we need to produce a low current, low emittance beam. This note describes the generation of two pencil beams and their dynamic through the Linac.

Linac design for the European spallation source

Energy Technology Data Exchange (ETDEWEB)

Klein, H. [Universitaet Postfach, Frankfurt am Main (Germany)

1995-10-01

A study group has started to develop a conceptual design for a European Spallation Source (ESS). This pulsed 5 MW source presently consists of a 1.334 GeV linac and two compressor rings. In the following mainly the high intensity linac part will be discussed, which has some features of interest for accelerators for transmutation of radioactive waste too.

Integrated design of the SSC linac injector

International Nuclear Information System (INIS)

Evans, D.; Valiecnti, R.; Wood, F.

1992-01-01

The Ion Source, Low Energy Beam Transport (LEBT), and Radio Frequency Quadrupole (RFQ) of the Superconducting Super Collider (SSC) Linac act as a unit (referred to as the Linac Injector), the Ion Source and LEBT being cantilevered off of the RFQ. Immediately adjacent to both ends of the RFQ cavity proper are endwall chambers containing beam instrumentation and independently-operated vacuum isolation valves. The Linac Injector delivers 30 mA of H - beam at 2.5 MeV. This paper describes the design constraints imposed on the endwalls, aspects of the integration of the Ion Source and LEBT including attachment to the RFQ, maintainability and interchangeability of LEBTs, vacuum systems for each component, and the design of necessary support structure. (Author) 2 tab

Commissioning and Operational Experience With an Intermediate Upgrade Cryomodule for the CEBAF 12 GeV Upgrade

International Nuclear Information System (INIS)

Thomas Powers; Davis, G.; Michael Drury; Christiana Grenoble; Hovater, J.; Lawrence King; Tomasz Plawski; Joseph Preble

2005-01-01

Three cryomodules have been designed and built as intermediate prototypes for the CEBAF 12 GeV upgrade. This paper will discuss the commissioning and operational experience with the second of these cryomodules, which was installed and commissioned in the Jefferson Lab 10 kW Free Electron Laser Facility. Within the cryomodule are eight 7-cell, 1497 MHz cavities. It was designed to accelerate 1 mA of beam in excess of 70 MV and to have the same footprint as a standard CEBAF cryomodule. The cryomodule was installed in parallel with the FEL beam line in the spring of 2004 and characterized simultaneous with beam delivery. It was installed in the beam line in the early summer of 2004 and has since been operated as part of an energy recovered linac with 5 mA of beam current and 75 MV accelerating gradient for extended periods of time. Additionally, it was operated at 1 mA of beam current and 80 MV of accelerating gradient for several hours without a trip. In the latter operating mode the beam current was limited by the injector setup

rf quadrupole linac: a new low-energy accelerator

International Nuclear Information System (INIS)

Hamm, R.W.; Crandall, K.R.; Fuller, C.W.

1980-01-01

A new concept in low-energy particle accelerators, the radio-frequency quadrupole (RFQ) linac, is currently being developed at the Los Alamos National Scientific Laboratory. In this new linear accelerating structure both the focusing and accelerating forces are produced by the rf fields. It can accept a high-current, low-velocity dc ion beam and bunch it with a high capture efficiency. The performance of this structure as a low-energy linear accelerator has been verified with the successful construction of a proton RFQ linac. This test structure has accelerated 38 mA of protons from 100 keV to 640 keV in 1.1 meters with a capture efficiency greater than 80%. In this paper a general description of the RFQ linac and an outline of the basic RFQ linac design procedure are presented in addition to the experimental results from the test accelerator. Finally, several applications of this new accelerator are discussed

Overview of High Intensity Linac Programs in Europe

CERN Document Server

Garoby, R

2004-01-01

Recent years have seen a boost in the support by the European Union (EU) of accelerator research in Europe. Provided they coordinate their efforts and define common goals and strategies, laboratories and institutions from the member states can receive a financial support reaching 50% of the total project cost. In the field of High Intensity Linacs, the EU has already supported the EURISOL initiative for nuclear physics, which this year is applying for funding of a Design Study, and the development of linacs for Waste Transmutation. More recently, an initiative for high-energy physics has been approved, which includes a programme for the development of pulsed linac technologies. The coordination and synergy imposed by the EU rules increase the benefit of the allocated resources. Combined with the ongoing internal projects in the partner laboratories, these European initiatives represent a strong effort focussed towards the development of linac technologies. This paper summarises the requests from the various E...

Conceptual Design of the Linac4 Main Dump

CERN Document Server

Leitao, I V; Maglioni, C

2012-01-01

Linac4 is the new CERN linear accelerator intended to replace the ageing Linac2 as the injector to the Proton Synchrotron Booster (PSB) for increasing the luminosity of the Large Hadron Collider (LHC). By delivering a 160MeV H- beam, Linac4 will provide the necessary conditions to double the brightness and intensity of the beam extracted from the PSB. This paper describes the conceptual design of the Linac4 Main Dump, where two different concepts relying respectively on water and air cooling were compared and evaluated. Based on the application of analytical models for the energy deposited by the beam, heat conduction and cooling concepts, a parametric study was performed. This approach allowed the identification of the “optimal” configuration for these two conceptual geometries and their relative comparison. Besides giving the theoretical guidelines for the design of the new dump, this work also contributes to the development of analytical tools to allow a better understanding of the influence of the se...

Preinjector for Linac 1, Faraday cage

CERN Multimedia

1974-01-01

The 50 MeV Linac 1 started up in 1958 as injector to the 26 GeV PS, with a 520 kV Cockcroft-Walton generator as its preinjector, housed in a vast Faraday cage, visible here. When the Cockcroft-Walton broke down in 1973, it was replaced by a much smaller SAMES generator, of the kind used for electrostatic separators. From 1980 on, Linac 2 took over as injector for the 800 MeV Booster, and Linac 1 continued as injector for LEAR. In 1984, the electrostatic preinjector (i.e. the Faraday cage with its contents, SAMES generator and all) was replaced by a 520 keV RFQ. At the lower left corner we see the HV connectors to the SAMES generator, at the right edge part of the opened electronics-platform. Jean-Luc Vallet sees to it that all parts are properly grounded. See also 7403073X, 7403074X, 7403081X, 7403083X.

An induction Linac driven heavy-ion fusion systems model

International Nuclear Information System (INIS)

Zuckerman, D.S.; Driemeyer, D.E.; Waganer, L.M.; Dudziak, D.J.

1988-01-01

A computerized systems model of a heavy-ion fusion (HIF) reactor power plant is presented. The model can be used to analyze the behavior and projected costs of a commercial power plant using an induction linear accelerator (Linac) as a driver. Each major component of the model (targets, reactor cavity, Linac, beam transport, power flow, balance of plant, and costing) is discussed. Various target, reactor cavity, Linac, and beam transport schemes are examined and compared. The preferred operating regime for such a power plant is also examined. The results show that HIF power plants can compete with other advanced energy concepts at the 1000-MW (electric) power level [cost of electricity (COE) -- 50 mill/kW . h] provided that the cost savings predicted for Linacs using higher charge-state ions (+3) can be realized

New linac technology - for SSC, and beyond

International Nuclear Information System (INIS)

Jameson, R.A.

1983-01-01

With recent agreement on the high priority of seeking funding for a Superconducting Super Collider (SSC), it is appropriate to consider the injector linac requirements for such a machine. In so doing, the status of established technique and advantages of near-term R and D with relatively clear payoff are established, giving a base line for some speculation about linac possibilities even further in the future

LFSC - Linac Feedback Simulation Code

Energy Technology Data Exchange (ETDEWEB)

Ivanov, Valentin; /Fermilab

2008-05-01

The computer program LFSC (<Linac Feedback Simulation Code>) is a numerical tool for simulation beam based feedback in high performance linacs. The code LFSC is based on the earlier version developed by a collective of authors at SLAC (L.Hendrickson, R. McEwen, T. Himel, H. Shoaee, S. Shah, P. Emma, P. Schultz) during 1990-2005. That code was successively used in simulation of SLC, TESLA, CLIC and NLC projects. It can simulate as pulse-to-pulse feedback on timescale corresponding to 5-100 Hz, as slower feedbacks, operating in the 0.1-1 Hz range in the Main Linac and Beam Delivery System. The code LFSC is running under Matlab for MS Windows operating system. It contains about 30,000 lines of source code in more than 260 subroutines. The code uses the LIAR ('Linear Accelerator Research code') for particle tracking under ground motion and technical noise perturbations. It uses the Guinea Pig code to simulate the luminosity performance. A set of input files includes the lattice description (XSIF format), and plane text files with numerical parameters, wake fields, ground motion data etc. The Matlab environment provides a flexible system for graphical output.

BARC-TIFR Pelletron Linac facility

International Nuclear Information System (INIS)

Gore, J.A.; Gupta, A.K.; Saxena, A.

2017-01-01

The Pelletron Accelerator, set up as a collaborative project between the Bhabha Atomic Research Centre and the Tata Institute of Fundamental Research, has been serving as the workhorse for the heavy ion accelerator based research in India since its commissioning in December 30, 1988. The facility was augmented with an indigenously developed superconducting Linac booster to enhance the energy of the Pelletron accelerated beams and was fully commissioned on November 28, 2007. The augmented facility is renamed as Pelletron Linac facility (PLF). While the PLF is predominantly utilized by the experimental users from BARC and TIFR, the users include researchers from other research institutions and universities within India and abroad

Transverse Matching Progress Of The SNS Superconducting Linac

International Nuclear Information System (INIS)

Zhang, Yan; Cousineau, Sarah M.; Liu, Yun

2011-01-01

Experience using laser-wire beam profile measurement to perform transverse beam matching in the SNS superconducting linac is discussed. As the SNS beam power is ramped up to 1 MW, transverse beam matching becomes a concern to control beam loss and residual activation in the linac. In our experiments, however, beam loss is not very sensitive to the matching condition. In addition, we have encountered difficulties in performing a satisfactory transverse matching with the envelope model currently available in the XAL software framework. Offline data analysis from multi-particle tracking simulation shows that the accuracy of the current online model may not be sufficient for modeling the SC linac.

Argonne tandem as injector to a superconducting linac

International Nuclear Information System (INIS)

Yntema, J.L.; Den Hartog, P.K.; Henning, W.; Kutschera, W.

1980-01-01

The Argonne Tandem uses Pelletron chains, NEC accelerator tubes, and a dual closed-corona system. Its main function is to be an injector for a superconducting linear accelerator. As long as the transverse and longitudinal emittances are within the acceptance of the linac, the output beam quality of the tandem-linac system is essentially determined by the tandem. The sensitivity of the linac to the longitudinal emittance ΔEΔt of the incident beam makes the output beam quality dependent on the negative-ion velocity distribution in the source, transit-time effects in the tandem, molecular-beam dissociation, and stripper-foil uniformity. This paper discusses these beam-degrading effects

Stabilization of the RF system at the SPring-8 linac

CERN Document Server

Asaka, T; Hori, T; Kobayashi, T; Mizuno, A; Sakaki, H; Suzuki, S; Taniuchi, T; Yanagida, K; Yokomizo, H; Yoshikawa, H

2002-01-01

Beam energy variation of the SPring-8 linac was 1% or more at the start of beam commissioning. Depending on fluctuation, beam transmission efficiency from the linac to the booster synchrotron was significantly affected, and beam intensity in the booster synchrotron changed 20-30%. This caused delay of optimization of the various parameters in the booster synchrotron. More problematic, the beam intensities stored in each RF (radio frequency) bucket of the storage ring at SPring-8 were all different from each other. The users utilizing synchrotron radiation requested that the beam intensity in each RF bucket be as uniform as possible. It was thus a pressing necessity to stabilize the beam energy in the linac. Investigation of the cause has clarified that the various apparatuses installed in the linac periodically changed depending on circumstances and utilities such as the air conditioner, cooling water and electric power. After various improvements, beam energy stability in the linac of <0.06% rms was attai...

A laser-wire beam-energy and beam-profile monitor at the BNL linac

Energy Technology Data Exchange (ETDEWEB)

Connolly, R.; Degen, C.; DeSanto, L.; Meng, W.; Michnoff, R.; Minty, M.; Nayak, S.

2011-03-28

In 2009 a beam-energy monitor was installed in the high energy beam transport (HEBT) line at the Brookhaven National Lab linac. This device measures the energies of electrons stripped from the 40mA H{sup -} beam by background gas. Electrons are stripped by the 2.0x10{sup -7}torr residual gas at a rate of {approx}1.5x10{sup -8}/cm. Since beam electrons have the same velocities as beam protons, the beam proton energy is deduced by multiplying the electron energy by m{sub p}/m{sub e}=1836. A 183.6MeV H{sup -} beam produces 100keV electrons. In 2010 we installed an optics plates containing a laser and scanning optics to add beam-profile measurement capability via photodetachment. Our 100mJ/pulse, Q-switched laser neutralizes 70% of the beam during its 10ns pulse. This paper describes the upgrades to the detector and gives profile and energy measurements.

Operational experiences of the spallation neutron source superconducting linac and power ramp-up

International Nuclear Information System (INIS)

Kim, Sang-Ho

2009-01-01

The spallation neutron source (SNS) is a second generation pulsed neutron source and designed to provide a 1-GeV, 1.44-MW proton beam to a mercury target for neutron production. Since the commissioning of the accelerator complex in 2006, the SNS has started its operation for neutron production and beam power ramp-up has been in progress toward the design goal. All subsystems of the SNS were designed and developed for substantial improvements compared to existing accelerators because the design beam power is almost an order of magnitude higher compared to existing neutron facilities and the achievable neutron scattering performance will exceed present sources by more than a factor of 20 to 100. In this paper, the operational experiences with the SNS Superconducting Linac (SCL), Power Ramp-up Plan to reach the design goal and the Power Upgrade Plan (PUP) will be presented including machine, subsystem and beam related issues.

A magnetized Einzel lens electron dump for the Linac4 H− ion source

CERN Document Server

Midttun, O; Kronberger, M; Lettry, J; Pereira, H; Scrivens, R

2013-01-01

Linac4 is a 160 MeV linear accelerator which will inject negative hydrogen ions (H−) into CERN’s Proton Synchrotron Booster, a required upgrade to improve the beam brightness in the LHC injector chain. A volume production RF ion source, based on the design of the DESY RF source was implemented, but showed considerable electron dump ablation during operation at 45 keV beam energy. To reduce the electron beam power density in the dump, a magnetized Einzel lens is designed that reduces the beam energy to 10 keV before permanentmagnets dump the electrons on a tungsten surface. Presented in this paper are simulations of the design using IBSimu, the tunable range of parameters depending on the extracted H− and electron current, as well as details of the implementation, the choice of pulsed power converters and the electrode alignment system. In addition, simulations of proton extraction from this source will be shown.

Managing hydrogen and molecules in bitumen upgrading : technology and research opportunities

Energy Technology Data Exchange (ETDEWEB)

Gray, M.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

2006-07-01

An innovative concept in oil sands mining, extraction and upgrading was presented with reference to selectively removing metals. The approach presently used to upgrade bitumen is to drive the properties of slurry mixtures closer to conventional crude oils. However, it is necessary to remove unwanted contaminants and to convert nearly all of the vacuum residues. The yield and value of the final product can be improved by maximizing the hydrogen content of the liquid products. The currently used and proposed upgrading methods are based on technologies developed between 1929 and 1954, including coking, hydrotreating, hydroconversion, and gasification. This study compared the main technologies for upgrading in terms of management of raw materials and hydrogen. The feasibility of improving recovery by using new approaches to separate bitumen was considered. It was concluded that the rejection of large fractions of bitumen as coke or asphaltenes is undesirable. New thermal process face design challenges such as distillation versus cracking coking and fouling. There is much potential for breakthrough in asphaltene precipitation technologies, based on paraffinic froth treatment concepts. tabs., figs.

Reduction of losses in linacs for protons or heavy ions

International Nuclear Information System (INIS)

Claus, J.

1977-01-01

It is necessary to minimize the beam losses in linacs for high average currents in order to avoid serious problems due to radiation damage, dissipation and radio activation of the accelerator structure. A large part of the losses in existing linacs is due to incomplete bunching of the injected beam. Proposed improvements generally appear to be deficient in one or more respects if applied to linacs with conventional frequencies, injection energies and current densities. By preceding the linac proper with an accelerating structure and an energy analyzer, it becomes possible to separate the particles that remained outside the buckets from those that are inside so that they can be dumped in a controlled manner

Radio frequency linear accelerators for NDT applications: Basic overview of RF linacs

International Nuclear Information System (INIS)

Hansen, H.J.

1998-01-01

High energy X-ray radiography can be an important part of a quality control program. In this article the author will present an overview of the technology found in a typical high energy X-ray source, the radio frequency (RF) linear accelerator. In NDT, linacs are used primarily for the inspection of thick sections of materials. Linacs are also used in applications such as high energy computed tomography of specimens greater than 1 m thick and cargo container inspection. Recent developments in reliable portable linacs are opening up other applications such as field inspection of pipelines, ships, bridges, and other civil infrastructure. The replacement of isotopes (such as Co-60) by the linac is an area for growth in the future. The shorter exposure times, improved image capabilities, and greatly reduced regulatory requirements of the linac make a persuasive argument for the replacement of isotopes with a portable linac. The linacs discussed here are those with X-ray energies from 1 to 20 MeV intended for use in NDT applications. The discussion will be in very broad terms; it will be impossible to discuss every variation in linac design. In addition, some topics have been necessarily simplified to increase the comprehensibility for a wider audience

Upgrade program of the high current heavy ion UNILAC as an injector for FAIR

International Nuclear Information System (INIS)

Barth, W.; Bayer, W.; Dahl, L.; Groening, L.; Richter, S.; Yaramyshev, S.

2007-01-01

Presently, the GSI facility consists of the heavy ion high current linac UNILAC and the synchrotron SIS 18. For the FAIR project the existing GSI accelerator complex is foreseen to serve as an injector for up to 10 12 U 28+ particles/s on the target. For this purpose an U 28+ beam current of 15 emA inside of the SIS 18 acceptance is required from the UNILAC for the multi-turn injection to the synchrotron up to its space charge limit. Different hardware measures and careful fine tuning in all sections of the UNILAC during the last years resulted in an increase of the beam intensity of up to a factor of seven. To meet the FAIR requirements a further improvement of the beam brilliance at the synchrotron entrance of about a factor of five is necessary. Several upgrade measures are planned and are partially on the realization stage. Simultaneously experimental and numerical studies of the UNILAC are going on and directed to the optimization of the machine and to investigations of the influence of the upgrade measures to the performance of the whole accelerator

Preinjector for Linac 1, accelerating column

CERN Multimedia

1974-01-01

For a description of the Linac 1 preinjector, please see first 7403070X. High up on the wall of the Faraday cage (7403073X) is this drum-shaped container of the ion source (7403083X). It is mounted at the HV end of the accelerating column through which the ions (usually protons; many other types of ions in the course of its long history) proceed through the Faraday cage wall to the low-energy end (at ground potential) of Linac 1. The 520 kV accelerating voltage was supplied by a SAMES generator (7403074X).

Compensated linac beam colliding with a stored beam

International Nuclear Information System (INIS)

Csonka, P.L.; Oregon Univ., Eugene

1981-01-01

The disruptive effect of a linac beam on a beam circulating in a storage ring can be reduced by compensating for the space charge of the linac beam with a beam which is oppositely charged, may have different bunchlength as well as lower energy, and need not be circulating in a storage ring. (orig.)

Properties of heavy ion linacs with alternating phase focusing

International Nuclear Information System (INIS)

Deitinghoff, H.; Junior, P.; Klein, H.

1976-01-01

General aspects for the application of alternating phase focusing are discussed. The results demand necessary linac parameters. The possibility of their accomplishment by already existing or feasible linac structures with acceleration rates of 2 - 3 MV/m will be considered

Beam halo in high-intensity hadron linacs

Energy Technology Data Exchange (ETDEWEB)

Gerigk, F

2006-12-21

This document aims to cover the most relevant mechanisms for the development of beam halo in high-intensity hadron linacs. The introduction outlines the various applications of high-intensity linacs and it will explain why, in the case of the CERN Superconducting Proton Linac (SPL) study a linac was chosen to provide a high-power beam, rather than a different kind of accelerator. The basic equations, needed for the understanding of halo development are derived and employed to study the effects of initial and distributed mismatch on high-current beams. The basic concepts of the particle-core model, envelope modes, parametric resonances, the free-energy approach, and the idea of core-core resonances are introduced and extended to study beams in realistic linac lattices. The approach taken is to study the behavior of beams not only in simplified theoretical focusing structures but to highlight the beam dynamics in realistic accelerators. All effects which are described and derived with simplified analytic models, are tested in realistic lattices and are thus related to observable effects in linear accelerators. This approach involves the use of high-performance particle tracking codes, which are needed to simulate the behavior of the outermost particles in distributions of up to 100 million macro particles. In the end a set of design rules are established and their impact on the design of a typical high-intensity machine, the CERN SPL, is shown. The examples given in this document refer to two different design evolutions of the SPL study: the first conceptual design report (SPL I) and the second conceptual design report (SPL II). (orig.)

submitter Radiation Protection Studies for CERN LINAC4/SPL Accelerator Complex

CERN Document Server

Mauro, Egidio; Silari, Marco

2009-01-01

CERN is presently designing a new chain of accelerators to replace the present Proton Synchrotron (PS) complex: a 160 MeV room-temperature H$^-$ linac (Linac4) to replace the present 50 MeV proton linac injector, a 3.5 GeV Superconducting Proton Linac (SPL) to replace the 1.4 GeV PS booster (PSB) and a 50 GeV synchrotron (named PS2) to replace the 26 GeV PS. Linac4 has been funded and the civil engineering work started in October 2008, whilst the SPL is in an advanced stage of design. Beyond injecting into the future 50 GeV PS, the ultimate goal of the SPL is to generate a 4 MW beam for the production of intense neutrino beams. The radiation protection design is driven by the latter requirement. This thesis summarizes the radiation protection studies conducted for Linac4. FLUKA Monte Carlo simulations, complemented by analytical estimates, were performed 1) to evaluate the propagation of neutrons through the waveguide, ventilation and cable ducts placed along the accelerator, 2) to estimate the radiological i...

CEBAF Cryomodule Commissioning in the South Linac

International Nuclear Information System (INIS)

M. Drury; H. Lankford; T. Lee; J. Marshall; J. Preble; Q. Saulter; W. Schneider; Michael Spata; Mark Wiseman

1993-01-01

When complete, the Continuous Electron Beam Accelerator Facility will house a 4 GeV recirculating linear accelerator containing 42 1/4 cryomodules arrayed in two antiparallel linacs and an injector. Currently, 38 1/4 cryomodules have been installed. Each cryomodule contains eight superconducting niobium 5-cell rf cavities that operate at 1.497 GHz[1]. A cryomodule must provide an energy gain of 20 MeV to the 200 mu-A beam[2]. The resultant dynamic heat load must be less than 45 W. The cavity parameters that are measured during the commissioning process include the external Q's (Q(sub ext)) of the cavity ports, the unloaded Q (Q(sub 0)) of the cavity as a function of accelerating gradient, and the maximum operating gradient of the cavity[3]. Finally, the mechanical tuners are cycled and characterized. A portable test stand allows local control of the rf system and provides automated data acquisition. During the period from April 1993 through September 1993, 16 of the 20 cryomodules installed in the South Linac were commissioned. All cryomodules tested in the South Linac meet or exceed the CEBAF specifications. This paper describes the results of the commissioning of the first 10 cryomodules in the South Linac

Full power to the first Linac4 module

CERN Multimedia

Francesco Poppi

2010-01-01

Since last week the first of a total of 23 accelerating structures for Linac4 has been undergoing high-power tests. Although still a prototype, this structure is destined to be the first of the 12 PIMS cavities to be installed in the Linac4 tunnel and it has been completely designed, developed and constructed at CERN.   The PIMS prototype. The new Linac4 has 4 different types of accelerating structures. The PI-Mode Structures (PIMS) are the last stage and are designed to accelerate protons up to 160 MeV. “PIMS have never before been used to accelerate protons”, explains Frank Gerigk, the project engineer responsible for the Linac4 accelerating structures. “In LEP, they were used to accelerate electrons, and now we have modified them and improved several design features to make them suitable for protons”. The first prototype was entirely manufactured in the CERN workshop. Due to the size of the pieces it was difficult to achieve and preserve the required to...

Heavy-ion acceleration with a superconducting linac

International Nuclear Information System (INIS)

Bollinger, L.M.

1988-01-01

This year, 1988, is the tenth anniversary of the first use of RF superconductivity to accelerate heavy ions. In June 1978, the first two superconducting resonators of the Argonne Tandem-Linac Accelerator System (ATLAS) were used to boost the energy of a 19 F beam from the tandem, and by September 1978 a 5-resonator linac provided an 16 O beam for a nuclear-physics experiment. Since then, the superconducting linac has grown steadily in size and capability until now there are 42 accelerating structures and 4 bunchers. Throughout this period, the system was used routinely for physics research, and by now the total time with beam on target is 35,000 hours. Lessons learned from this long running experience and some key technical developments that made it possible are reviewed in this paper. 19 refs., 3 figs., 2 tabs

Wire scanner data analysis for the SSC Linac emittance measurement

International Nuclear Information System (INIS)

Yao, C.Y.; Hurd, J.W.; Sage, J.

1993-07-01

The wire scanners are designed in the SSC Linac for measurement of beam emittance at various locations. In order to obtain beam parameters from the scan signal, a data analysis program was developed that considers the problems of noise reduction, machine modeling, parameter fitting, and correction. This program is intended as a tool for Linac commissioning and also as part of the Linac control program. Some of the results from commissioning runs are presented

High-Performance Beam Simulator for the LANSCE Linac

International Nuclear Information System (INIS)

Pang, Xiaoying; Rybarcyk, Lawrence J.; Baily, Scott A.

2012-01-01

A high performance multiparticle tracking simulator is currently under development at Los Alamos. The heart of the simulator is based upon the beam dynamics simulation algorithms of the PARMILA code, but implemented in C++ on Graphics Processing Unit (GPU) hardware using NVIDIA's CUDA platform. Linac operating set points are provided to the simulator via the EPICS control system so that changes of the real time linac parameters are tracked and the simulation results updated automatically. This simulator will provide valuable insight into the beam dynamics along a linac in pseudo real-time, especially where direct measurements of the beam properties do not exist. Details regarding the approach, benefits and performance are presented.

6 MeV RF Linac for cargo scanning and industrial radiography

International Nuclear Information System (INIS)

2017-01-01

RF Linac-based X-ray sources are very widely used for cargo-scanning and industrial X-ray radiography applications. A 6 MeV on-axis coupled-cavity S-band RF linac has been designed, developed and tested successfully at Electron Beam Centre, Navi Mumbai. This facility falls under the purview of BARC Safety Council, which has conducted safety reviews and awarded regulatory clearances for the operation of the linac system. This paper outlines the salient features of the 6 MeV linac, its safety aspects and test results. A brief history of regulatory aspects is also presented

Detuning effect in a traveling wave type linac

International Nuclear Information System (INIS)

Arai, Shigeaki.

1981-10-01

Detailed measurement of acceleration characteristics has been performed on a 15 MeV electron linac as the injector of the electron synchrotron at Institute for Nuclear Study, University of Tokyo. Remarkable feature of the results is that the energy gain as well as the energy spread of the output beam, are optimized when the linac is operated with the microwave whose frequency is higher than the resonant frequency of the accelerator waveguide. The difference of this operating frequency from the resonant frequency grows up as the beam intensity is increased, and amounts to 250 KHz when the beam intensity is 350 mA. In order to clarify the mechanism of the phenomena, the interaction of electron beam with the microwave in the accelerator structure of traveling wave type, is examined on the linac and also on a test accelerator structure. For the analysis of the experimental results, the normal mode method which has been used for standing wave cavities, is developed so as to be applied to the accelerator structure of traveling wave type. The results of analysis show that the observed phenomena at INS linac are caused by the resonant frequency shift, detuning, due to the reactive beam loading and this detuning effects are compensated by use of the microwave of higher frequency. Thus the detuning effects are significant even in the traveling wave type linac composed of buncher and regular sections as well as in the standing wave type accelerator structure. (author)

A High Current Proton Linac with 352 MHz SC Cavities

CERN Document Server

Pagani, C; Pierini, P

1996-01-01

A proposal for a 10-120 mA proton linac employing superconducting beta-graded, CERN type, four cell cavities at 352 MHz is presented. The high energy part (100 MeV-1 GeV) of the machine is split in three beta-graded sections, and transverse focusing is provided via a periodic doublet array. All the parameters, like power in the couplers and accelerating fields in the cavities, are within the state of the art, achieved in operating machines. A first stage of operation at 30 mA beam current is proposed, while the upgrade of the machine to 120 mA operation can be obtained increasing the number of klystrons and couplers per cavity. The additional coupler ports, up to four, will be integrated in the cavity design. Preliminary calculations indicate that beam transport is feasible, given the wide aperture of the 352 MHz structures. A capital cost of less than 100 M$ at 10 mA, reaching up to 280 M$ for the 120 mA extension, has been estimated for the superconducting high energy section (100 MeV-1 GeV). The high effic...

Major projects for the use of high power linacs

International Nuclear Information System (INIS)

Prome, M.

1996-01-01

A review of the major projects for high power linacs is given. The field covers the projects aiming at the transmutation of nuclear waste or the production of tritium, as well as the production of neutrons for hybrid reactors or basic research with neutron sources. The technologies which arc common to all the projects are discussed. Comments are made on the technical difficulties encountered by all the projects, and the special problems of the pulsed linacs are mentioned. Elements for a comparison of normal conducting linacs versus superconducting ones are given. Finally the technical developments being made in various laboratories are reviewed. (author)

A new method for improving beam quality of LINAC

International Nuclear Information System (INIS)

Xie Jialin; Li Fengtian; Wang Yanshan; Wang Bosi

1999-01-01

The principle of the self-adaptive feed-forward (SAFF) control to improve the beam quality of linac is introduced. the analytical procedure for calculating the control signals, the structure of a practical control system, and applications of SAFF in klystron, RF gun, and linac are presented, especially the application in the thermionic gun whose response is non-linear, time-variant and of large time-delay. The described control system is operational and some primary experimental results have been obtained, including the control of amplitude and phase fluctuations of the klystron output, the microwave field in the gun cavity and linac

Initial operation of the Argonne superconducting heavy-ion linac

Energy Technology Data Exchange (ETDEWEB)

Shepard, K. W.

1979-01-01

Initial operation and recent development of the Argonne superconducting heavy-ion linac are discussed. The linac has been developed in order to demonstrate a cost-effective means of extending the performance of electrostatic tandem accelerators. The results of beam acceleration tests which began in June 1978 are described. At present 7 of a planned array of 22 resonators are operating on-line, and the linac system provides an effective accelerating potential of 7.5 MV. Although some technical problems remain, the level of performance and reliability is sufficient that appreciable beam time is becoming available to users.

Emittance reconstruction technique for the Linac4 high energy commissioning

CERN Document Server

Lallement, JB; Posocco, PA

2012-01-01

Linac4 is a new 160 MeV linear accelerator for negative Hydrogen ions (H-) presently under construction which will replace the 50 MeV proton Linac2 as injector for the CERN proton accelerator complex. Linac4 is 80 meters long and comprises a Low Energy Beam Transport line, a 3 MeV RFQ, a MEBT, a 50 MeV DTL, a 100 MeV CCDTL and a PIMS up to 160 MeV. The commissioning of the Linac is scheduled to start in 2013. It will be divided into several steps corresponding to the commissioning of the different accelerating structures. A temporary measurement bench will be dedicated to the high energy commissioning from 30 to 100 MeV (DTL tanks 2 and 3, and CCDTL). The commissioning of the PIMS will be done using the permanent equipment installed in between the end of the Linac and the main dump. This note describes the technique we will use for reconstructing the transverse emittances and the expected results.

Linac design algorithm with symmetric segments

International Nuclear Information System (INIS)

Takeda, Harunori; Young, L.M.; Nath, S.; Billen, J.H.; Stovall, J.E.

1996-01-01

The cell lengths in linacs of traditional design are typically graded as a function of particle velocity. By making groups of cells and individual cells symmetric in both the CCDTL AND CCL, the cavity design as well as mechanical design and fabrication is simplified without compromising the performance. We have implemented a design algorithm in the PARMILA code in which cells and multi-cavity segments are made symmetric, significantly reducing the number of unique components. Using the symmetric algorithm, a sample linac design was generated and its performance compared with a similar one of conventional design

EG and G electron linac modifications

International Nuclear Information System (INIS)

Norris, N.J.; Detch, J.L.; Kocimski, S.M.; Sawyer, C.R.; Hudson, C.L.

1986-01-01

A three-year modification of the EG and G electron linac has been performed to replace obsolete equipment and bring all subsystems up to the current state of the art. Components and subsystems were designed, constructed, and tested off-line to minimize interruption of experiments. The configuration of the modified linac is shown schematically, and performance characteristics are give. Each subsystem is described, including: the electron gun; solenoid focusing system; subharmonic bunchers; accelerating system; RF system; klystron modulators and power supplies; control system; beam handling system; vacuum system; and beam current monitors. 7 refs., 4 figs., 2 tabs

Optimization of steering elements in the RIA driver linac

International Nuclear Information System (INIS)

Lessner, E. S.; Aseev, V. S.; Ostroumov, P. N.; Physics

2005-01-01

The driver linac of the projected RIA facility is a versatile accelerator, a 1.4-GV, CW superconducting (SC) linac designed to simultaneously accelerate several heavy-ion charge states, providing beams from proton to uranium at 400 MeV/u at power levels at a minimum of 100 kW and up to 400 kW for most beams. Acceleration of multiple-charge-state uranium beams places stringent requirements on the linac design. A steering algorithm was derived that fulfilled the driver's real estate requirements, such as placement of steering dipole coils on SC solenoids and of beam position monitors outside cryostats, and beam-dynamics requirements, such as coupling effects induced by the focusing solenoids. The algorithm has been fully integrated into the tracking code TRACK and it is used to study and optimize the number and position of steering elements that minimize the multiple-beam centroid oscillations and preserve the beam emittance under misalignments of accelerating and transverse focusing elements in the driver linac

HOM Dampers or not in Superconducting RF Proton Linacs

CERN Document Server

Tückmantel, Joachim

2009-01-01

Circular machines are plagued by Coupled Bunch Instabilities, driven by impedance peaks, irrespectively of their frequency relation to machine lines; hence all cavity Higher Order Modes are possible drivers. This is the fundamental reason that all superconducting RF cavities in circular machines are equipped with HOM dampers. This raises the question if HOM damping would not be imperative also in high current proton linacs where a mechanism akin to CBI might exist. To clarify this question we have simulated the longitudinal bunched beam dynamics in linacs, allowing bunch-to-bunch variations in time-of-arrival. Simulations were executed for a generic proton linac with properties close to SNS or the planned SPL at CERN. It was found that for monopole HOMs with high Qext large beam scatter or even beam loss cannot be excluded. Therefore omitting HOM dampers on superconducting RF cavities in high current proton linacs, even pulsed ones, is a very risky decision.

HOM Dampers or not in SUPERCONDUCTING RF Proton Linacs

CERN Document Server

Tückmantel, Joachim

2009-01-01

Circular machines are plagued by Coupled Bunch Instabilities, driven by impedance peaks, irrespectively of their frequency relation to machine lines; hence all cavity Higher Order Modes are possible drivers. This is the fundamental reason that all superconducting RF cavities in circular machines are equipped with HOM dampers. This raises the question if HOM damping would not be imperative also in high current proton linacs where a mechanism akin to CBI might exist. To clarify this question we have simulated the longitudinal bunched beam dynamics in linacs, allowing bunch-to-bunch variations in time-of-arrival. Simulations were executed for a generic proton linac with properties close to SNS or the planned SPL at CERN. It was found that for monopole HOMs with high Qext large beam scatter or even beam loss cannot be excluded. Therefore omitting HOM dampers on superconducting RF cavities in high current proton linacs, even pulsed ones, is a very risky decision.

Failure Modes Analysis for the MSU-RIA Driver Linac

CERN Document Server

Wu, Xiaoyu; Gorelov, Dmitry; Grimm, Terry L; Marti, Felix; York, Richard

2005-01-01

Previous end-to-end beam dynamics simulation studies* using experimentally-based input beams including alignment and rf errors and variation in charge-stripping foil thickness have indicated that the Rare Isotope Accelerator (RIA) driver linac proposed by MSU has adequate transverse and longitudinal acceptances to accelerate light and heavy ions to final energies of at least 400 MeV/u with beam powers of 100 to 400 kW. During linac operation, equipment loss due to, for example, cavity contamination, availability of cryogens, or failure of rf or power supply systems, will lead to at least a temporary loss of some of the cavities and focusing elements. To achieve high facility availability, each segment of the linac should be capable of adequate performance even with failed elements. Beam dynamics studies were performed to evaluate the linac performance under various scenarios of failed cavities and focusing elements with proper correction schemes, in order to prove the flexibility and robustness of the driver ...

Beam Loss in Linacs

CERN Document Server

Plum, M.A.

2016-01-01

Beam loss is a critical issue in high-intensity accelerators, and much effort is expended during both the design and operation phases to minimize the loss and to keep it to manageable levels. As new accelerators become ever more powerful, beam loss becomes even more critical. Linacs for H- ion beams, such as the one at the Oak Ridge Spallation Neutron Source, have many more loss mechanisms compared to H+ (proton) linacs, such as the one being designed for the European Spallation Neutron Source. Interesting H- beam loss mechanisms include residual gas stripping, H+ capture and acceleration, field stripping, black-body radiation and the recently discovered intra-beam stripping mechanism. Beam halo formation, and ion source or RF turn on/off transients, are examples of beam loss mechanisms that are common for both H+ and H- accelerators. Machine protection systems play an important role in limiting the beam loss.

An operator-console system of the photon factory injector LINAC

International Nuclear Information System (INIS)

Nakahara, Kazuo; Abe, Isamu; Furukawa, Kazuro; Kamikubota, Norihiko

1990-01-01

It is sometimes difficult to unify accelerator control systems constructed in different ways. This problem arose in unifying the control systems of the injector linac and the storage ring making up the Photon Factory of the National Laboratory for High Energy Physics. One easy approach is to unify only the operator consoles; the unified console is connected to both separate control systems using gateways. The operator-console system of the Photon Factory injector linac has been designed and constructed using this approach. It consists of several workstations interconnected via a local-area network, a gateway to the old linac control network and a CATV system for the real-time display of the accelerator status. In this way the linac will be controlled from the control center of the Photon Factory storage ring. (orig.)

CAS CERN Accelerator School: Cyclotrons, linacs and their applications. Proceedings

International Nuclear Information System (INIS)

Turner, S.

1996-01-01

These proceedings present the lectures given at the eighth specialized course organized by the CERN Accelerator School (CAS), the topic this time being 'Cyclotrons, Linacs and Their Applications'. Following an introductory lecture on linacs, the fundamental features of electron, ion and induction linacs are described together with their RF systems and particle sources. Cyclotrons are then introduced followed by details of their different types, their magnet and RF design, and their injection and extraction systems, with a glance towards exotic and possible future machines. Chapters are then presented on the use of linacs and cyclotrons for medical, fission, fusion and material applications, as well as for isotope production. Finally, descriptions of the design of a radioisotope facility, the matching of accelerators to their task and the computational tools used in their design are included. (orig.)

CAS CERN Accelerator School: Cyclotrons, linacs and their applications. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Turner, S [ed.

1996-03-04

These proceedings present the lectures given at the eighth specialized course organized by the CERN Accelerator School (CAS), the topic this time being `Cyclotrons, Linacs and Their Applications`. Following an introductory lecture on linacs, the fundamental features of electron, ion and induction linacs are described together with their RF systems and particle sources. Cyclotrons are then introduced followed by details of their different types, their magnet and RF design, and their injection and extraction systems, with a glance towards exotic and possible future machines. Chapters are then presented on the use of linacs and cyclotrons for medical, fission, fusion and material applications, as well as for isotope production. Finally, descriptions of the design of a radioisotope facility, the matching of accelerators to their task and the computational tools used in their design are included. (orig.).

Efficient recovery and upgrading of waste heat from humid air in the forest industry. Pre-feasibility study; Energieffektivisering inom skogsindustrin genom spillvaermeaatervinning fraan vaatluft. Foerprojektering och loensamhetsbedoemning av anlaeggningsalternativ

Energy Technology Data Exchange (ETDEWEB)

Ingman, Daniel; Gustafsson, Maria; Westermark, Mats

2007-12-15

Within the pulp and paper and saw mill industries there are large quantities of waste heat in the form of moist air or humid flue gases. The temperature and dew point are generally too low for the streams to be useful as process heat. Waste heat can be recovered from humid gas streams e.g. outgoing gas from paper machines, lumber dryers, green liquor flash tanks, flue gases from power and recovery boilers, lime kilns etc. In general, this waste heat is available around 50-65 deg C. One way to utilise the heat on a higher temperature level is by means of heat pumping. The present project studies the possibility to use a recently developed absorption heat pump technology for upgrading waste heat to district heating or process steam. Via direct contact between the absorbent and humid gas stream, the moisture is condensed in the absorbent and the latent heat simultaneously increases the liquid's temperature. A number of process solutions have been calculated in terms of technical and economic performance. The process can be designed for production of hot water or process steam from upgraded waste heat. The end product is indirectly governed be the selection of absorbent or working medium. Investigated absorbents are solutions of potassium formate, sodium hydroxide and phosphoric acid, of which the former two have been included in the techno-economic calculations. The upgraded heat can either save costs by replacing primary fuel or result in increased revenues by exporting produced heat. Internally, the produced heat often replaces oil or electricity on the margin. The choice of regeneration method for the used and diluted absorbent is governed by the mill's energy situation. Industries with large waste heat resources, high value on process steam and use of heat on district heat level, waste heat driven regeneration is advisable. Industries with similar value on MP and LP steam should use back-pressure regeneration with MP steam for optimum cost and energy

first tank of Linac 1

CERN Multimedia

This was the first tank of the linear accelerator Linac1, the injection system for the Proton Synchrotron, It ran for 34 years (1958 - 1992). Protons entered at the far end and were accelerated between the copper drift tubes by an oscillating electromagnetic field. The field flipped 200 million times a second (200 MHz) so the protons spent 5 nanoseconds crossing a drift tube and a gap. Moving down the tank, the tubes and gaps had to get longer as the protons gained speed. The tank accelerated protons from 500 KeV to 10 MeV. Linac1 was also used to accelerate deutrons and alpha particles for the Intersecting Storage Rings and oxygen and sulpher ions for the Super Proton Synchrotron heavy ion programme.

Conceptual designs of beam choppers for RFQ linacs

International Nuclear Information System (INIS)

Nath, S.; Stevens, S.R. Jr.; Wangler, T.P.

1995-01-01

A design study at Los Alamos of a linac/accumulator ring facility for a pulsed neutron spallation source calls for an H - beam with a chopped structure of approximately 200-ns beam-free segments every 600-ns. The required angular impulse can easily be provided with existing pulse power technology and traveling wave structures with a transverse electric field similar to those now available. The deflected beam is then restored by suitable collimation. Chopping is relatively easily done at sufficiently low energies, where the beam is easily deflected, and beam powers are not too large. However, the energy should be high enough so that the space-charge blow-up of the beam can be controlled with adequate focusing. LAMPF presently uses a traveling-wave beam chopper at 750 keV, before injection into the drift tube linac (DTL). In the new linac designs, a radiofrequency quadrupole (RFQ) linac would typically bunch and accelerate the high intensity H - beam from 100 keV to 7 MeV. In this paper, the authors present concepts for beam-chopper systems both before and after the RFQ. The beam-optics designs are presented, together with numerical simulation results

SRF LINAC for future extension of the PEFP

Energy Technology Data Exchange (ETDEWEB)

Kim, Han Sung; Kwon, Hyeok Jung; Seol, Kyoung Tae; Jang, Ji Ho; Cho, Yong Sub [Proton Engineering Frontier Project, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-04-15

A study on the superconducting RF linac is underway in order to increase the beam energy up to 1 GeV by extending the Proton Engineering Frontier Project (PEFP) 100-MeV linac. The operating frequency of the PEFP superconducting linac (SCL) is 700 MHz, which is determined by the fact that the frequency of the existing normal conducting linac is 350 MHz. A preliminary study on the beam dynamics showed that two types of cavities with geometrical betas of 0.50 and 0.74 could cover the entire energy range from 100 MeV to 1 GeV. An inductive output tube (IOT) based RF system is under consideration as a high-power RF source for the SCL due to its low operating voltage and high efficiency. As a prototyping activity for a reduced beta cavity, a five-cell cavity with a geometrical beta of 0.42 was designed and fabricated. A vertical test of the prototype cavity at low temperatures was performed to check the performance of the cavity. The design study and the prototyping activity for the PEFP SCL will be presented in this paper.

SRF LINAC for future extension of the PEFP

International Nuclear Information System (INIS)

Kim, Han Sung; Kwon, Hyeok Jung; Seol, Kyoung Tae; Jang, Ji Ho; Cho, Yong Sub

2014-01-01

A study on the superconducting RF linac is underway in order to increase the beam energy up to 1 GeV by extending the Proton Engineering Frontier Project (PEFP) 100-MeV linac. The operating frequency of the PEFP superconducting linac (SCL) is 700 MHz, which is determined by the fact that the frequency of the existing normal conducting linac is 350 MHz. A preliminary study on the beam dynamics showed that two types of cavities with geometrical betas of 0.50 and 0.74 could cover the entire energy range from 100 MeV to 1 GeV. An inductive output tube (IOT) based RF system is under consideration as a high-power RF source for the SCL due to its low operating voltage and high efficiency. As a prototyping activity for a reduced beta cavity, a five-cell cavity with a geometrical beta of 0.42 was designed and fabricated. A vertical test of the prototype cavity at low temperatures was performed to check the performance of the cavity. The design study and the prototyping activity for the PEFP SCL will be presented in this paper.

Upgraded phase control system for superconducting low-velocity accelerating structures

International Nuclear Information System (INIS)

Added, N.

1992-01-01

Microphonic-induced fluctuations in the RF eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the RF phase. The tuning system must handle a reactive power proportional to the product of the frequency range and the RF energy content of the Rf cavity. The fast tuner for the SC resonators in the ATLAS heavy-ion linac is a voltage-controlled reactance based on an array of PIN diodes operating immersed in liquid nitrogen. This paper discusses recent upgrades to the ATLAS fast tuner which can now provide as much as 30 KVA of reactive tuning capability with a real RF power loss of less than 300 watts. The design was guided by numerical modeling of all elements of the device. Also discussed is the RF coupler which can couple 30 KW from 77 K tuner to a 42 K resonant cavity with less than 2 W of RF loss into 4.2 K

Upgraded phase control system for superconducting low-velocity accelerating structures

Energy Technology Data Exchange (ETDEWEB)

Added, N. (Sao Paulo Univ., SP (Brazil). Dept. de Fisica Nuclear); Clifft, B.E.; Shepard, K.W. (Argonne National Lab., IL (United States))

1992-01-01

Microphonic-induced fluctuations in the RF eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the RF phase. The tuning system must handle a reactive power proportional to the product of the frequency range and the RF energy content of the Rf cavity. The fast tuner for the SC resonators in the ATLAS heavy-ion linac is a voltage-controlled reactance based on an array of PIN diodes operating immersed in liquid nitrogen. This paper discusses recent upgrades to the ATLAS fast tuner which can now provide as much as 30 KVA of reactive tuning capability with a real RF power loss of less than 300 watts. The design was guided by numerical modeling of all elements of the device. Also discussed is the RF coupler which can couple 30 KW from 77 K tuner to a 42 K resonant cavity with less than 2 W of RF loss into 4.2 K.

Upgraded phase control system for superconducting low-velocity accelerating structures

Energy Technology Data Exchange (ETDEWEB)

Added, N. [Sao Paulo Univ., SP (Brazil). Dept. de Fisica Nuclear; Clifft, B.E.; Shepard, K.W. [Argonne National Lab., IL (United States)

1992-09-01

Microphonic-induced fluctuations in the RF eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the RF phase. The tuning system must handle a reactive power proportional to the product of the frequency range and the RF energy content of the Rf cavity. The fast tuner for the SC resonators in the ATLAS heavy-ion linac is a voltage-controlled reactance based on an array of PIN diodes operating immersed in liquid nitrogen. This paper discusses recent upgrades to the ATLAS fast tuner which can now provide as much as 30 KVA of reactive tuning capability with a real RF power loss of less than 300 watts. The design was guided by numerical modeling of all elements of the device. Also discussed is the RF coupler which can couple 30 KW from 77 K tuner to a 42 K resonant cavity with less than 2 W of RF loss into 4.2 K.

Approach of a failure analysis for the MYRRHA linac

International Nuclear Information System (INIS)

Carneiro, J.P.; Medeiros-Romao, L.; Salemne, R.; Vandeplassche, D.; Biarotte, J.L.; Bouly, F.; Uriot, D.

2015-01-01

The MYRRHA project currently under development at SCK-CEN (Mol, Belgium) is a subcritical research reactor that requires a 600 MeV proton accelerator as a driver. This linac is expected to produce a beam power of 1.5 MW onto a spallation target for the reactor to deliver a thermal power around 70 MW. Thermomechanical considerations of the spallation target set stringent requirements on the beam trip rate which should not exceed 40 trips/year for interruptions longer than three seconds. The 3 underlying principles in the design of the MYRRHA linac are elements redundancy (like the dual-injector), elements operation at de-rated values (like cavities operating at about 30% from their nominal operating points) and the fault tolerance concept, which allows the failure of a beamline component to be compensated by its neighbouring elements. Studies presented in this document show that in the event of a failure of the first cryo-module or the first quadrupole doublet the linac can resume nominal operation with a re-matched lattice. Since the fault tolerance procedure is expected to work more efficiently at higher energies (due to lower space charge effects) we can extrapolate from our studies that the MYRRHA linac is expected to operate with the failure of any cryo-module or quadrupole doublet in the main linac. A virtual accelerator-based control system is mandatory for the operation of the MYRRHA linac to ensure the very fast implementation (<3 seconds) of the fault tolerance procedure. The virtual accelerator uses a beam dynamics code (like TRACEWIN or TRACK) to compute the model of the real accelerator in operation and interacts with this later through the accelerator control command

Injection schemes for the TOP Linac; Schemi di iniezione per il TOP Linac

Energy Technology Data Exchange (ETDEWEB)

Picardi, L.; Ronsivalle, C. [ENEA, Centro Ricerche Frascati, Frascati, RM (Italy). Dipt. Innovazione; Bartolini, R. [Istituto Superiore di Sanita' , Rome (Italy)

1999-07-01

In this report two schemes are studied for the injection in the SCDTL section of the TOP Linac of the proton beam produced by a 7 MeV linear accelerator. The project derives by an agreement between ENEA (National Agency for New Technology, Energy and Environment) and ISS. In these new versions of the design the constraint of a synchronization of the radio frequencies of the two accelerators is suppressed. [Italian] In questo rapporto sono studiati due schemi di iniezione nella sezione accelerante SCDTL a 3 GHz del TOP (terapia oncologica con protoni) linac del fascio di protoni generato da un acceleratore lineare di 7 MeV. L'acceleratore e' frutto di una convenzione tra L'ENEA e l'Istituto Superiore di Sanita'. Rispetto a versioni precedenti del progetto, viene eliminato il vincolo della sincronizzazione delle radiofrequenze dei due acceleratori.

Syngas upgrading in a membrane reactor with thin Pd-alloy supported membrane

NARCIS (Netherlands)

Brunetti, A.; Caravella, A.; Fernandez Gesalaga, E.; Pacheco Tanaka, D. A.; Gallucci, F.; Drioli, E.; Curcio, E.; Viviente, J. L.; Barbieri, G.

2015-01-01

In hydrogen production, the syngas streams produced by reformers and/or coal gasification plants contain a large amount of H2 and CO in need of upgrading. To this purpose, reactors using Pd-based membranes have been widely studied as they allow separation and recovery of a pure hydrogen stream.

Mechanical features of a 700 MHz bridge-coupled drift tube linac

International Nuclear Information System (INIS)

Liska, D.; Smith, P.; Carlisle, L.; Larkin, T.; Lawrence, G.; Garnett, R.

1992-01-01

Modem linac designs for treating radioactive waste achieve high proton currents through funneling at low energy, typically around 20 MeV. The resulting switch to a high-frequency accelerating structure poses severe performance and fabrication difficulties below 100 MeV. Above 100 MeV, proven coupled-cavity linacs (CCLS) are available. However, at 20 MeV one must choose between a high-frequency drift-tube linac (DTL) or a coupled-cavity linac with very short cells. Potential radiation damage from the CW beam, excessive RF power losses, multipactoring, and fabricability all enter into this decision. At Los Alamos, we have developed designs for a bridge-coupled DTL (BCDTL) that, like a CCL, uses lattice focusing elements and bridge couplers, but that unlike a CCL, accelerates the beam in simple, short, large-aperture DTL modules with no internal quadrupole focusing. Thus, the BCDTL consumes less power than the CCL linac without beam performance and is simpler and cheaper to fabricate in the 20 to 100 MeV range

Numerical simulations of stripping effects in high-intensity hydrogen ion linacs

Directory of Open Access Journals (Sweden)

J.-P. Carneiro

2009-04-01

Full Text Available Numerical simulations of H^{-} stripping losses from blackbody radiation, electromagnetic fields, and residual gas have been implemented into the beam dynamics code TRACK. Estimates of the stripping losses along two high-intensity H^{-} linacs are presented: the Spallation Neutron Source linac currently being operated at Oak Ridge National Laboratory and an 8 GeV superconducting linac currently being designed at Fermi National Accelerator Laboratory.

Focussing magnets for proton Linac of ADS

International Nuclear Information System (INIS)

Malhotra, Sanjay; Mahapatra, U.; Singh, Pitamber; Choudhury, R.K.; Goel, Priyanshu; Verma, Vishnu; Bhattacharya, S.; Srivastava, G.P.; Kailas, S.; Sahni, V.C.

2009-01-01

A linear accelerator comprising of Radio frequency quadruple (RFQ) and drift tube linac (DTL) is being developed by BARC. The Alvarez type post-coupled cw DTL accelerates protons from an energy of 3 MeV to 20 MeV. The drift tube linac is excited in TM010 mode, wherein the particles are accelerated by longitudinal electric fields at the gap crossings between drift tubes. The particles are subjected to transverse RF defocusing forces at the gap crossings due to the increasing electric fields in the gap. The transverse defocusing is corrected by housing magnetic quadrupole focussing lenses inside the drift tubes. The permanent magnet quadrupoles (PMQs) are placed inside the hermetically sealed drift tubes and provide a constant magnetic field gradient in the beam aperture. This paper discusses various aspects of magnetic design, selection of magnetic materials and the engineering development involved in the prototype development of these drift tubes for proton Linac. (author)

Superconducting linacs used with tandems

International Nuclear Information System (INIS)

Ben-Zvi, I.

1984-01-01

The main features of superconducting linacs used as post-accelerators of tandems are reviewed. Various aspects of resonators, cryogenics and electronics are discussed, and recent advances in the field are presented. (orig.)

Design considerations for high-current superconducting ion linacs

International Nuclear Information System (INIS)

Delayen, J.R.; Bohn, C.L.; Micklich, B.J.; Roche, C.T.; Sagalovsky, L.

1993-01-01

Superconducting linacs may be a viable option for high-current applications such as fusion materials irradiation testing, spallation neutron source, transmutation of radioactive waste, tritium production, and energy production. These linacs must run reliably for many years and allow easy routine maintenance. Superconducting cavities operate efficiently with high cw gradients, properties which help to reduce operating and capital costs, respectively. However, cost-effectiveness is not the sole consideration in these applications. For example, beam impingement must be essentially eliminated to prevent unsafe radioactivation of the accelerating structures, and thus large apertures are needed through which to pass the beam. Because of their high efficiency, superconducting cavities can be designed with very large bore apertures, thereby reducing the effect of beam impingement. Key aspects of high-current cw superconducting linac designs are explored in this context

Wakefields in SLAC linac collimators

Directory of Open Access Journals (Sweden)

A. Novokhatski

2014-12-01

Full Text Available When a beam travels near collimator jaws, it gets an energy loss and a transverse kick due to the backreaction of the beam field diffracted from the jaws. The effect becomes very important for an intense short bunch when a tight collimation of the background beam halo is required. In the Linac Coherent Light Source at SLAC a collimation system is used to protect the undulators from radiation due to particles in the beam halo. The halo is most likely formed from gun dark current or dark current in some of the accelerating sections. However, collimators are also responsible for the generation of wake fields. The wake field effect from the collimators not only brings an additional energy jitter and change in the trajectory of the beam, but it also rotates the beam on the phase plane, which consequently leads to a degradation of the performance of the Free Electron Laser at the Linac Coherent Light Source. In this paper, we describe a model of the wake field radiation in the SLAC linac collimators. We use the results of a numerical simulation to illustrate the model. Based on the model, we derive simple formulas for the bunch energy loss and the average kick. We also present results from experimental measurements that confirm our model.

Upgrade of the CMS hardron calorimeter for an upgraded LHC

OpenAIRE

Anderson, Jake

2012-01-01

The CMS barrel and endcap hadron calorimeters (Hcal) upgrading the current photo-sensors are hybrid photodiodes (HPDs) to meet the demands of the upgraded luminosity of the LHC. A key aspect of the Hcal upgrade is to add longitudinal segmentation to improve background rejection, energy resolution, and electron isolation at L1 trigger. The increased segmentation can be achieved by replacing the HPD's with multi-pixel Geiger-mode avalanche photodiodes. The upgraded electron...

Radiation protection studies for a high-power 160 MeV proton linac

CERN Document Server

Mauro, Egidio

2009-01-01

CERN is presently designing a new chain of accelerators to replace the present Proton Synchrotron (PS) complex: a 160 MeV room-temperature H− linac (Linac4) to replace the present 50 MeV proton linac injector, a 3.5 GeV Superconducting Proton Linac (SPL) to replace the 1.4 GeV PS Booster (PSB) and a 50 GeV synchrotron (named PS2) to replace the 26 GeV PS. Linac4 has been funded and the civil engineering work started in October 2008, whilst the SPL is in an advanced stage of design. Beyond injecting into the future 50 GeV PS, the ultimate goal of the SPL is to generate a 4 MW beam for the production of intense neutrino beams. The radiation protection design is driven by the latter requirement. This work summarizes the radiation protection studies conducted for Linac4. FLUKA Monte Carlo simulations, complemented by analytical estimates, were performed to evaluate the propagation of neutrons through the waveguide, ventilation and cable ducts placed along the accelerator, to estimate the radiological impact of ...

The RF system for FELI linac

International Nuclear Information System (INIS)

Morii, Y.; Abe, S.; Keishi, T.; Tomimasu, T.

1995-01-01

FELI (Free Electron Laser Research Institute, Inc.) is constructing a Free Electron Laser facility covering from 20μm (infra red region) to 0.35μm (ultra violet region), using as S-band linac. The linac consists of a thermoionic 0.5ns-pulse triggered gun, a 714-MHz SHB (subharmonic buncher), a 2856-MHz standing wave type buncher, and seven ETL (Electro-technical Laboratory) type accelerating sections. An RF system of the linac for FELs is required of long pulse duration and high stability. Two S-band klystrons (TOSHIBA E3729) are operated in three pulse operation modes (pulse width and peak RF power): 24μs-24MW, 12.5μs-34MW, 0.5μs-70MW. Each klystron modulator has a PFN consisting of 4 parallel networks of 24 capacitors and 24 variable inductors, and it has a line switch of an optical thyristor stack. An S-band klystron and its modulator were combined to test their performance at the works of NISSIN ELECTRIC Co. in December 1993. These equipments were installed at FELI in January 1994. The design and experimental results of the RF system are summarized in this paper. (author)

The Linac4 DTL Prototype: Low and High Power Measurements

CERN Document Server

De Michele, G; Marques-Balula, J; Ramberger, S

2012-01-01

The prototype of the Linac4 Drift Tube Linac (DTL) has undergone low power measurements in order to verify the RF coupling and to adjust the post-coupler lengths based on bead-pull and spectrum measurements. Following the installation at the test stand, the cavity has been subjected to high power operation at Linac4 and SPL duty cycles. Saturation effects and multipacting have been observed and linked to X-ray emission. Voltage holding is reported in the presence of magnetic fields from permanent magnet quadrupoles (PMQ) installed in the first drift tubes.

Induction linac drivers for commercial heavy-ion beam fusion

International Nuclear Information System (INIS)

Keefe, D.

1987-11-01

This paper discusses induction linac drivers necessary to accelerate heavy ions at inertial fusion targets. Topics discussed are: driver configurations, the current-amplifying induction linac, high current beam behavior and emittance growth, new considerations for driver design, the heavy ion fusion systems study, and future studies. 13 refs., 6 figs., 1 tab

Berkeley research program on ion-induction linacs for inertial fusion

International Nuclear Information System (INIS)

Keefe, D.; Rosenblum, S.S.

1982-03-01

The following areas of research are described: (1) driver studies, (2) induction linac technology, (3) core materials, (4) insulators, (5) modulator-switches and pulse forming network, (6) induction linac accelerators and prototype modules, and (7) a high-temperature experiment

On the e-linac-based neutron yield

International Nuclear Information System (INIS)

Bunatyan, G.G.; Nikolenko, V.G.; Popov, A.B.

2010-01-01

We treat neutron generating in high atomic number materials due to the photonuclear reactions induced by the Bremsstrahlung of an electron beam produced by linear electron accelerator (e-linac). The dependence of neutron yield on the electron energy and the irradiated sample size is considered for various sample materials. The calculations are performed without resort to the so-called 'numerical Monte Carlo simulation'. The acquired neutron yields are well correlated with the data asserted in investigations performed at a number of the e-linac-driven neutron sources

Operation of the tandem-linac accelerator

International Nuclear Information System (INIS)

Anon.

1985-01-01

The tandem-linac accelerator system is operated as a source of energetic heavy-ion projectiles for research in several areas of nuclear physics and occasionally in other areas of science. The accelerator system consists of a 9-MV tandem electrostatic accelerator and a superconducting-linac energy booster that can provide an additional 20 MV of acceleration. A figure shows the layout of this system, which will be operated in its present form until September 1985, when it will be incorporated into the larger ATLAS system. In both the present and future forms the accelerator is designed to provide the exceptional beam quality and overall versatility required for precision nuclear-structure research

Investigation of the mechanical performance of Siemens linacs components during arc

DEFF Research Database (Denmark)

Rowshanfarzad, Pejman; Häring, Peter; Lynggaard Riis, Hans

2015-01-01

to linac rotation were separately investigated by acquisition of 37 EPID images of a simple phantom with five ball bearings at various gantry angles. A fast and robust software package was developed for automated analysis of image data. Three Siemens linacs were investigated. RESULTS: The average EPID sag...... for effective investigation of the behavior of Siemens linac components with gantry rotation. Such a comprehensive study has been performed for the first time on Siemens machines....

Safety aspects of pulsed YAYOI and Japan Linac Booster

International Nuclear Information System (INIS)

An, S.; Oka, Y.; Wakabayashi, J.

1976-01-01

The paper consists of two parts. The first part is concerned with safety aspects of pulsed YAYOI. Reactivity pulsed operation of YAYOI is performed with reactivity oscillating devices. Inherent safety characteristics due to dilation of metal fuel, a small amount of f.p. build up, reactor operation preserving fuel integrity and experience on transient experiments are the principal basis for safety assurance. Conditions for pulsed operation, namely, maximum allowable temperature, maximum number of repetition of pulsed operation and so on are derived from the consideration on the integrity of fuel. Instrumentation and control systems are reinforced by displacement meter in the core, interlock system, special timer for pulsed operation, additional scram conditions and reactivity meter. Accident analysis and safety evaluation indicate the conservative safety features of the facility. Concerning pulsed operation of YAYOI combined with Linac, special attention must be given to the design of Linac target placed in the core. In the second part are described the principal guide-lines and basic ideas for safety design of Japan Linac Booster (JLB). JLB is a U-Mo fueled and sodium cooled fast reactor with rotating reflector and Linac target in the core. The pulsed neutrons are injected into the core coincidentally with repetitive peaks of reactivity. Design of rotating reflector and Linac target system are the new and important safety problems not yet encountered in the usual sodium fast reactor design. The axis of the rotating reflector is horizontal, which avoids the collision of reflector block with core in the case of failure of rotating reflector. The separate cooling channels for target and the Linac electron beam control system are provided. Reactor shut down and power control systems must be carefully designed. Core meltdown and disassembly accident is considered as a hypothetical accident which is a basis for containment system design. (auth.)

Review of induction linac studies

International Nuclear Information System (INIS)

Keefe, Denis

1984-01-01

The major emphasis of the U.S. program in Heavy Ion Fusion Accelerator Research is on developing and understanding induction-linac systems that employ multiple beams of high-current heavy ions. The culmination of the plan lies in building the High Temperature Experiment (HTE) which will involve an ion induction linac to deliver multiple high current beams, that can be focussed and overlapped on a two-millimeter diameter spot. A sequence of three major experimental activities are as follows. In the Single-Beam Transport Experiment (SBTE), the stability or otherwise transport of a high-current Cs +1 beam over a long distance is tested. In the Multiple-Beam Experiment (MBE), the experiment is designed to simulate on a small scale as many as possible of the features to be encountered in the HTE. (Mori, K.)

Design and analysis of X-band femtosecond linac

Energy Technology Data Exchange (ETDEWEB)

Uesaka, M; Kozawa, T; Takeshita, A; Kobayashi, T; Ueda, T; Miya, K [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

1997-03-01

Femtosecond quantum phenomena research project is proposed at Nuclear Engineering Research Laboratory, University of Tokyo. The research facility consists of an X-band (11.424GHz) femtosecond electron linac, a femtosecond wavelength tunable laser, two S-band (2.856GHz) picosecond electron linacs and measuring equipments. Especially, we aim to generate a 100 fs (FWHM) electron single bunch with more than 1 nC at the X-band femtosecond linac. Ultrafast processes in radiation physics, chemistry, material science and microscopic electromagnetic phenomena are going to be analyzed there. Here the design and analysis of an X-band femtosecond linac is presented. The simulation of electron dynamics is carried out including magnetic pulse compression by using PARMELA and SUPERFISH. It is found by the simulation that the 600 ps (tail-to-tail) electron emission from a 200 kV thermionic gun can be bunched and compressed to 110 fs (FWHM) with the charge of 0.8 nC which gives 7.3 kA. We plan to use one high power X-band klystron which can supply 60 MW with more than 200 ns pulse duration. The flatness of plateau of the pulse should be 0.2% for stable ultrashort bunch generation. (author)

ETL linac facility and free-electron lasers

International Nuclear Information System (INIS)

Yamazaki, T.; Noguchi, T.; Mikado, T.; Sugiyama, S.; Yamada, K.; Chiwaki, M.; Ohgaki, H.; Suzuki, R.; Sei, N.

1993-01-01

An outline is presented of the recent development on the ETL (Electro-technical Laboratory) electron-linac facility and storage-ring FELs (free-electron lasers). Some modifications including the injection system have been made to the linac. Four storage rings are working very well. The TERAS FEL system has been shut down after the successful oscillation around 590 nm. The new NIJI-IV FEL system has been proven to work well, and the current tunable wavelength range is over 100 nm (488-595 nm). Preparatory experiments on the FEL at shorter wavelength are underway. (author)

Progress in the Development of the TOP Linac

CERN Document Server

Picardi, L

2004-01-01

The TOP Linac (Oncological Therapy with Protons), under development by ENEA and ISS is a sequence of three pulsed (5 msec, 300 Hz) linear accelerators: a 7 MeV, 425 MHz RFQ+DTL (AccSys Model PL-7), a 7–65 MeV, 2998 MHz Side Coupled Drift Tube Linac (SCDTL) and a 65–200 MeV, variable energy 2998 MHz Side Coupled Linac (SCL). The first SCDTL module is composed by 11 DTL tanks coupled by 10 side cavities. The tanks has modified to overcome vacuum leakage that occurred during brazing, and now the module has been completed, and is ready to be tested with protons. The 7 MeV injector has been recently installed in the ENEA Frascati laboratories for preliminary test, before being transferred to the main Oncologycal Hospital in Rome, Istituto Regina Elena.

Production of slow-positron beams with an electron linac

International Nuclear Information System (INIS)

Howell, R.H.; Alvarez, R.A.; Stanek, M.

1982-01-01

Intense, pulsed beams of low-energy positrons have been produced by a high-energy beam from an electron linac. The production efficiency for low-energy positrons has been determined for electrons with 60 to 120 MeV energy, low-energy positron beams from a linac can be of much higher intensity than those beams currently derived from radioactive sources

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

Mechanical features of a 700-MHz bridge-coupled drift-tube linac

International Nuclear Information System (INIS)

Liska, D.; Smith, P.; Carlisle, L.; Larkin, T.; Lawrence, G.; Garnett, R.

1992-01-01

Modern linac designs for treating radioactive waste achieve high proton currents through funneling at low energy, typically around 20 MeV. The resulting switch to a high-frequency accelerating structure poses severe performance and fabrication difficulties below 100 MeV. Above 100 MeV, proven coupled-cavity linacs (CCLs) are available. However, at 20 MeV one must choose between a high-frequency drift-tube linac (DTL) or a coupled-cavity linac with very short cells. Potential radiation damage from the CW beam, excessive RF power losses, multipactoring, and fabricability all enter into this decision. At Los Alamos, we have developed designs for a bridge-coupled DTL (BCDTL) that, like a CCL, uses lattice focusing elements and bridge couplers, but that unlike a CCL, accelerates the beam in simple, short, large-aperture DTL modules with no internal quadrupole focusing. Thus, the BCDTL consumes less power than the CCL linac without beam performance and is simpler and cheaper to fabricate in the 20 to 100 MeV range. (Author) ref., tab., 3 figs

Status of the Argonne superconducting-linac heavy-ion energy booster

International Nuclear Information System (INIS)

Aron, J.; Benaroya, R.; Bollinger, L.M.; Clifft, B.E.; Henning, W.; Johnson, K.W.; Nixon, J.M.; Markovich, P.; Shepard, K.W.

1979-01-01

A superconducting linac is being constructed to provide an energy booster for heavy ions from an FN tandem. By late 1980 the linac will consist of 24 independently-phased superconducting resonators, and will provide an effective accelerating potential of more than 25 MV. While the linac is under construction, completed sections are being used to provide useful beam for nuclear physics experiments. In the most recent run with beam (June 1979), an eight resonator array provided an effective accelerating potential of 9.3 MV. Operation of a 12 resonator array is scheduled to begin in October 1979

Status of the Argonne superconducting-linac heavy-ion energy booster

Energy Technology Data Exchange (ETDEWEB)

Aron, J.; Benaroya, R.; Bollinger, L.M.; Clifft, B.E.; Henning, W.; Johnson, K.W.; Nixon, J.M.; Markovich, P.; Shepard, K.W.

1979-01-01

A superconducting linac is being constructed to provide an energy booster for heavy ions from an FN tandem. By late 1980 the linac will consist of 24 independently-phased superconducting resonators, and will provide an effective accelerating potential of more than 25 MV. While the linac is under construction, completed sections are being used to provide useful beam for nuclear physics experiments. In the most recent run with beam (June 1979), an eight resonator array provided an effective accelerating potential of 9.3 MV. Operation of a 12 resonator array is scheduled to begin in October 1979.

Measurement of the longitudinal wakefield and the bunch shape in the SLAC linac

International Nuclear Information System (INIS)

Bane, K.L.F.; Decker, F.J.; Seeman, J.T.; Zimmermann, F.

1997-05-01

The authors report on measurements of the bunch energy spectrum at the end of the SLAC linac. Using the spectra obtained for two different linac rf phases they obtain both the bunch induced voltage and the longitudinal distribution of the bunch. The measurement results are compared with theoretical predictions. In particular, the induced voltage is in good agreement with that obtained using the calculated wake function for the SLAC linac. This measurement technique may be useful for monitoring changes of the linac bunch shape in the SLC

Wakefield dependent emittance growth in the SLAC [Stanford Linear Accelerator Center] linac

International Nuclear Information System (INIS)

Bane, K.L.F.

1990-10-01

In this note we describe the emittance growth we can expect at bunch populations of N = 3,4,5 x 10 10 in the SLC linac. We will discuss briefly the effects of injection jitter, injection drift, and coherent oscillations starting in the middle of the linac. Finally, we will discuss in a more thorough manner the effects of random misalignment errors throughout the linac

UPGRADES

CERN Document Server

D. Contardo and J. Spalding

2013-01-01

There is very good progress in the execution of the LS1 projects and in launching construction of the Phase 1 upgrades. We focus here on two main achievements since the last CMS Week. The approval of the third Phase 1 TDR The preparation of the L1 Trigger Upgrade Technical Design Report has been a major effort of the collaboration at the beginning of this year, especially to develop supporting Trigger menu and physics performance studies. These studies have demonstrated the efficiency of the upgraded system to ensure low lepton and jet trigger thresholds, leading to a significant increase of the acceptance for the Higgs measurements, in the associated production mode and in the ττ decays, as well as for the stop searches involving multiple jets in the final state. The TDR was submitted to the LHCC in May and approved at the June committee meeting. It is now a public document, completing the series of the three TDRs describing the Phase 1 upgrades, with the new Pixel system and the HCAL rea...

Installation of the Gbar LINAC

CERN Multimedia

Maximilien, Brice

2017-01-01

Installation of the GBAR linac in its shielding bunker. The electrons accelerated to 10 MeV toward a target will produce the positrons that are necessary to form anti hydrogen with the antiprotons coming from the ELENA decelerator.

WE-D-BRD-01: Innovation in Radiation Therapy Delivery: Advanced Digital Linac Features

International Nuclear Information System (INIS)

Xing, L; Wong, J; Li, R

2014-01-01

Last few years has witnessed significant advances in linac technology and therapeutic dose delivery method. Digital linacs equipped with high dose rate FFF beams have been clinically implemented in a number of hospitals. Gated VMAT is becoming increasingly popular in treating tumors affected by respiratory motion. This session is devoted to update the audience with these technical advances and to present our experience in clinically implementing the new linacs and dose delivery methods. Topics to be covered include, technical features of new generation of linacs from different vendors, dosimetric characteristics and clinical need for FFF-beam based IMRT and VMAT, respiration-gated VMAT, the concept and implementation of station parameter optimized radiation therapy (SPORT), beam level imaging and onboard image guidance tools. Emphasis will be on providing fundamental understanding of the new treatment delivery and image guidance strategies, control systems, and the associated dosimetric characteristics. Commissioning and acceptance experience on these new treatment delivery technologies will be reported. Clinical experience and challenges encountered during the process of implementation of the new treatment techniques and future applications of the systems will also be highlighted. Learning Objectives: Present background knowledge of emerging digital linacs and summarize their key geometric and dosimetric features. SPORT as an emerging radiation therapy modality specifically designed to take advantage of digital linacs. Discuss issues related to the acceptance and commissioning of the digital linacs and FFF beams. Describe clinical utility of the new generation of digital linacs and their future applications

WE-D-BRD-01: Innovation in Radiation Therapy Delivery: Advanced Digital Linac Features

Energy Technology Data Exchange (ETDEWEB)

Xing, L [Stanford University, Stanford, CA (United States); Wong, J [Johns Hopkins University, Baltimore, MD (United States); Li, R [Stanford University, Palo Alto, CA (United States)

2014-06-15

Last few years has witnessed significant advances in linac technology and therapeutic dose delivery method. Digital linacs equipped with high dose rate FFF beams have been clinically implemented in a number of hospitals. Gated VMAT is becoming increasingly popular in treating tumors affected by respiratory motion. This session is devoted to update the audience with these technical advances and to present our experience in clinically implementing the new linacs and dose delivery methods. Topics to be covered include, technical features of new generation of linacs from different vendors, dosimetric characteristics and clinical need for FFF-beam based IMRT and VMAT, respiration-gated VMAT, the concept and implementation of station parameter optimized radiation therapy (SPORT), beam level imaging and onboard image guidance tools. Emphasis will be on providing fundamental understanding of the new treatment delivery and image guidance strategies, control systems, and the associated dosimetric characteristics. Commissioning and acceptance experience on these new treatment delivery technologies will be reported. Clinical experience and challenges encountered during the process of implementation of the new treatment techniques and future applications of the systems will also be highlighted. Learning Objectives: Present background knowledge of emerging digital linacs and summarize their key geometric and dosimetric features. SPORT as an emerging radiation therapy modality specifically designed to take advantage of digital linacs. Discuss issues related to the acceptance and commissioning of the digital linacs and FFF beams. Describe clinical utility of the new generation of digital linacs and their future applications.

Superconducting linac booster for NSC Pelletron

International Nuclear Information System (INIS)

Roy, A.; Prakash, P.N.; Ajithkumar, B.P.; Ghosh, S.; Changrani, T.; Mehta, R.; Sarkar, A.; Muralidhar, S.; Dutt, R.N.; Kumar, M.; Shepard, K.W.; and others.

1996-01-01

The progress made in the heavy ion superconducting linac booster project for the Nuclear Science Centre Pelletron accelerator is overviewed. Prototypes of the accelerating structure have been fabricated at Argonne National Laboratory and undergone several diagnostic tests. In the first phase heavy ions up to mass 80 will be accelerated to energies above the Coulomb barrier and in the second phase the mass limit would be increased to 120. The subsystems of the project are the basic accelerating structures, the RF instrumentation and control, the cryogenic system and the beam optics. Preliminary designs for the buncher and linac cryostats have been made. Several prototypes of RF electronics and control modules have been fabricated and tested. (R.P.)

LINAC4 takes a tour of Europe

CERN Multimedia

Katarina Anthony

2011-01-01

Along the German Autobahnen, a truck carrying 20 tonnes of copper is on its way to Poland. The metal has already made a short tour of Europe, yet the drive across the high-speed highway is only the beginning of its transformation into CERN’s next linear accelerator, LINAC4.   Grzegorz Wrochna (left), director of the Andrzej Soltan Institute for Nuclear Studies (IPJ), and Rolf Heuer (right), CERN DG, sign the framework agreement between the two institutes. By the summer of 2012, the PI-Mode Structures (PIMS) will be constructed and completely installed in the LINAC4 tunnel. The PIMS cavities are the final accelerating structures needed for LINAC4, and have been designed to accelerate protons from 100 to 160MeV. While the first cavity was built entirely at CERN, construction of the remaining cavities has become a larger, multi-national operation. In a 1 million euro framework agreement signed on 11 February by the Director-General, the Andrzej Soltan Institute for Nuclear Studies in Swie...

Experiments and prospects for induction linac drivers

International Nuclear Information System (INIS)

Keefe, D.

1986-05-01

In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental results on both these matters and also on the use of multiple beams (inside the same accelerating structure) will be described. A new examination of the most attractive properties of the induction linac for a fusion driver has clearly pointed to the advantage of using heavy ions with a charge-state greater than unity - perhaps q = 3 may be an optimum. This development places even greater importance on understanding space-charge limits and mechanisms for emittance growth; also, it will require a new emphasis on the development of a suitable ion source

Experiments and prospects for induction linac drivers

International Nuclear Information System (INIS)

Keefe, D.

1986-12-01

In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental results on both these matters and also on the use of multiple beams (inside the same accelerating structure) will be described. A new examination of the most attractive properties of the induction linac for a fusion driver has clearly pointed to the advantage of using heavy ions with a charge-state greater than unity - perhaps q = 3 may be an optimum. This development places even greater importance on understanding space-charge limits and mechanisms for emittance growth; also, it will require a new emphasis on the development of a suitable ion source

Design of LINAC4, A New Injector for the CERN Booster

CERN Document Server

Garoby, R; Lombardi, A M; Rossi, C; Vretenar, M; Gerigk, F

2004-01-01

A new H- linac (Linac4) is presently under study at CERN. This accelerator, based on normal conducting structures at 352 and 704 MHz, will provide a 30 mA 160 MeV H- beam to the CERN PS Booster (PSB), thus overcoming the present space-charge bottleneck at injection with a 50 MeV proton beam. Linac4 is conceived as the first stage of a future 2.2 GeV superconducting linac (SPL) and it is therefore designed for a higher duty cycle than necessary for the PSB. This paper discusses the design choices, presents the layout of the facility and illustrates the advantages for the LHC and other CERN users. The R&D and construction strategy, which mainly relies upon international collaborations, is also presented.

MEIC Proton Beam Formation with a Low Energy Linac

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yuhong [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2015-09-01

The MEIC proton and ion beams are generated, accumulated, accelerated and cooled in a new green-field ion injector complex designed specifically to support its high luminosity goal. This injector consists of sources, a linac and a small booster ring. In this paper we explore feasibility of a short ion linac that injects low-energy protons and ions into the booster ring.

Analysis of the LSC microbunching instability in MaRIE linac reference design

International Nuclear Information System (INIS)

Yampolsky, Nikolai

2016-01-01

In this report we estimate the effect of the microbunching instability in the MaRIE XFEL linac. The reference design for the linac is described in a separate report. The parameters of the L1, L2, and L3 linacs as well as BC1 and BC2 bunch compressors were the same as in the referenced report. The beam dynamics was assumed to be linear along the accelerator (which is a reasonable assumption for estimating the effect of the microbunching instability). The parameters of the bunch also match the parameters described in the referenced report. Additionally, it was assumed that the beam radius is equal to R = 100 m and does not change along linac. This assumption needs to be revisited at later studies. The beam dynamics during acceleration was accounted in the matrix formalism using a Matlab code. The input parameters for the linacs are: RF peak gradient, RF frequency, RF phase, linac length, and initial beam energy. The energy gain and the imposed chirp are calculated based on the RF parameters self-consistently. The bunch compressors are accounted in the matrix formalism as well. Each chicane is characterized by the beam energy and the R56 matrix element. It was confirmed that the linac and beam parameters described previously provide two-stage bunch compression with compression ratios of 10 and 20 resulting in the bunch of 3kA peak current.

Drift tubes of Linac 2

CERN Multimedia

Photographic Service

1977-01-01

Being redied for installation, those at the right are for tank 1, those on the left for tank 2. Contrary to Linac 1, which had drift-tubes supported on stems, here the tubes are suspended, for better mechanical stability.

An overview of BARC-TIFR pelletron linac facility

International Nuclear Information System (INIS)

Gupta, A.K.

2014-01-01

The 14UD Pelletron Accelerator at Mumbai has recently completed twenty five years of successful operation. The accelerator is primarily used for basic research in the fields of nuclear, atomic, condensed matter and material science. The superconducting Linac booster provides additional acceleration to the ions from Pelletron injector up to A∼60 region with E∼5 MeV/A. Further, an alternate injector system to the Superconducting LINAC booster is planned as an augmentation programme, comprising of a superconducting ECR ion source, room temperature RFQ and superconducting low-beta cavity resonators. This talk will provide an overview of the recent developmental activities carried out at the Pelletron Accelerator Facility, resulting in enhanced overall performance and uptime of the accelerator. The application oriented programs initiated at Pelletron Accelerator and the current status of the alternate injector system at the Pelletron-Linac facility will also be discussed. (author)

An overview of BARC-TIFR Pelletron-Linac Facility

International Nuclear Information System (INIS)

Gupta, A. K.

2015-01-01

The 14UD Pelletron Accelerator at Mumbai has recently completed twenty five years of successful operation. The accelerator is primarily used for basic research in the fields of nuclear, atomic, condensed matter and material science. The superconducting Linac booster provides additional acceleration to the ions from Pelletron injector up to A~60 region with E~5 MeV/A. Further, an alternate injector system to the Superconducting LINAC booster is planned as an augmentation programme, comprising of a superconducting ECR ion source, room temperature RFQ and superconducting low-beta cavity resonators. This talk will provide an overview of the recent developmental activities carried out at the Pelletron Accelerator Facility, resulting in enhanced overall performance and uptime of the accelerator. The application oriented programs initiated at Pelletron Accelerator and the current status of the alternate injector system at the Pelletron-Linac facility will also be discussed. (author)

Control processes and machine protection on ASDEX Upgrade

International Nuclear Information System (INIS)

Raupp, G.; Treutterer, W.; Mertens, V.; Neu, G.; Sips, A.; Zasche, D.; Zehetbauer, Th.

2007-01-01

Safe operation of ASDEX Upgrade is guaranteed by a conventional hierarchy of simple and robust hard-wired systems for personnel and machine protection featuring standardized switch-off procedures. Machine protection and handling of off-normal events is further enhanced and peak and lifetime stress minimized through the plasma control system. Based on a real-time process model supporting safety critical applications with data quality tagging, process self-monitoring, watchdog monitoring and alarm propagation, processes detect complex and critical failures and reliably perform case-sensitive counter measures. Intelligent real-time failure handling is done with hardware or software redundancy and performance degradation, or modification of reference values to continue or terminate discharges with reduced machine stress. Examples implemented so far on ASDEX Upgrade are given, such as recovery from measurement failures, switch-over of redundant actuators, handling of actuator limitations, detection of plasma instabilities, plasma state dependent soft landing, or handling of failed switch-off procedures through breakers disconnecting the machine from grid

Design of high-energy high-current linac with focusing by superconducting solenoids

Energy Technology Data Exchange (ETDEWEB)

Batskikh, G.I.; Belugin, V.M.; Bondarev, B.I. [Moscow Radiotechnical Institute (Russian Federation)] [and others

1995-10-01

The advancement of MRTI design for 1.5 GeV and 250 mA ion CW linac was presented in a previous report. In this new linac version all the way from input to output the ions are focused by magnetic fields of superconducting solenoids. The ion limit current is far beyond the needed value. The linac focusing channel offers major advantages over the more conventional ones. The acceptance is 1.7 times as large for such focusing channel as for quadrupole one. Concurrently, a random perturbation sensitivity for such channel is one order of magnitude smaller than in quadrupole channel. These focusing channel features allow to decrease beam matched radius and increase a linac radiation purity without aperture growth. {open_quotes}Regotron{close_quotes} is used as high power generator in linac main part. But D&W cavities need not be divided into sections connected by RF-bridges which denuded them of high coupling factor.

A new degassing membrane coupled upflow anaerobic sludge blanket (UASB) reactor to achieve in-situ biogas upgrading and recovery of dissolved CH4 from the anaerobic effluent

International Nuclear Information System (INIS)

Luo, Gang; Wang, Wen; Angelidaki, Irini

2014-01-01

Highlights: • A new UASB configuration was developed by coupling with degassing membrane. • In-situ biogas upgrading was achieved with high methane content (>90%). • Decrease of dissolved methane in the anaerobic effluent was achieved. - Abstract: A new technology for in-situ biogas upgrading and recovery of CH 4 from the effluent of biogas reactors was proposed and demonstrated in this study. A vacuum degassing membrane module was used to desorb CO 2 from the liquid phase of a biogas reactor. The degassing membrane was submerged into a degassing unit (DU). The results from batch experiments showed that mixing intensity, transmembrane pressure, pH and inorganic carbon concentration affected the CO 2 desorption rate in the DU. Then, the DU was directly connected to an upflow anaerobic sludge blanket (UASB) reactor. The results showed the CH 4 content was only 51.7% without desorption of CO 2 , while it increased when the liquid of UASB was recycled through the DU. The CH 4 content increased to 71.6%, 90%, and 94% with liquid recirculation rate through the DU of 0.21, 0.42 and 0.63 L/h, respectively. The loss of methane due to dissolution in the effluent was reduced by directly pumping the reactor effluent through the DU. In this way, the dissolved CH 4 concentration in the effluent decreased from higher than 0.94 mM to around 0.13 mM, and thus efficient recovery of CH 4 from the anaerobic effluent was achieved. In the whole operational period, the COD removal efficiency and CH 4 yield were not obviously affected by the gas desorption

Reliability model of SNS linac (spallation neutron source-ORNL)

International Nuclear Information System (INIS)

Pitigoi, A.; Fernandez, P.

2015-01-01

A reliability model of SNS LINAC (Spallation Neutron Source at Oak Ridge National Laboratory) has been developed using risk spectrum reliability analysis software and the analysis of the accelerator system's reliability has been performed. The analysis results have been evaluated by comparing them with the SNS operational data. This paper presents the main results and conclusions focusing on the definition of design weaknesses and provides recommendations to improve reliability of the MYRRHA ( linear accelerator. The reliability results show that the most affected SNS LINAC parts/systems are: 1) SCL (superconducting linac), front-end systems: IS, LEBT (low-energy beam transport line), MEBT (medium-energy beam transport line), diagnostics and controls; 2) RF systems (especially the SCL RF system); 3) power supplies and PS controllers. These results are in line with the records in the SNS logbook. The reliability issue that needs to be enforced in the linac design is the redundancy of the systems, subsystems and components most affected by failures. For compensation purposes, there is a need for intelligent fail-over redundancy implementation in controllers. Enough diagnostics has to be implemented to allow reliable functioning of the redundant solutions and to ensure the compensation function

High current induction linacs

International Nuclear Information System (INIS)

Barletta, W.; Faltens, A.; Henestroza, E.; Lee, E.

1994-07-01

Induction linacs are among the most powerful accelerators in existence. They have accelerated electron bunches of several kiloamperes, and are being investigated as drivers for heavy ion driven inertial confinement fusion (HIF), which requires peak beam currents of kiloamperes and average beam powers of some tens of megawatts. The requirement for waste transmutation with an 800 MeV proton or deuteron beam with an average current of 50 mA and an average power of 40 MW lies midway between the electron machines and the heavy ion machines in overall difficulty. Much of the technology and understanding of beam physics carries over from the previous machines to the new requirements. The induction linac allows use of a very large beam aperture, which may turn out to be crucial to reducing beam loss and machine activation from the beam halo. The major issues addressed here are transport of high intensity beams, availability of sources, efficiency of acceleration, and the state of the needed technology for the waste treatment application. Because of the transformer-like action of an induction core and the accompanying magnetizing current, induction linacs make the most economic sense and have the highest efficiencies with large beam currents. Based on present understanding of beam transport limits, induction core magnetizing current requirements, and pulse modulators, the efficiencies could be very high. The study of beam transport at high intensities has been the major activity of the HIF community. Beam transport and sources are limiting at low energies but are not significant constraints at the higher energies. As will be shown, the proton beams will be space-charge-dominated, for which the emittance has only a minor effect on the overall beam diameter but does determine the density falloff at the beam edge

Heavy-ion superconducting linacs

International Nuclear Information System (INIS)

Delayen, J.R.

1989-01-01

This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs

Heavy-ion superconducting linacs

Energy Technology Data Exchange (ETDEWEB)

Delayen, J.R.

1989-01-01

This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs.

Proton linacs for boron neutron capture therapy

International Nuclear Information System (INIS)

Lennox, A.J.

1993-08-01

Recent advances in the ability to deliver boron-containing drugs to brain tumors have generated interest in ∼4 MeV linacs as sources of epithermal neutrons for radiation therapy. In addition, fast neutron therapy facilities have been studying methods to moderate their beams to take advantage of the high cross section for epithermal neutrons on boron-10. This paper describes the technical issues involved in each approach and presents the motivation for undertaking such studies using the Fermilab linac. the problems which must be solved before therapy can begin are outlined. Status of preparatory work and results of preliminary measurements are presented

The FAIR proton linac

International Nuclear Information System (INIS)

Kester, O.

2015-01-01

FAIR - the Facility for Antiproton and Ion Research in Europe - constructed at GSI in Darmstadt comprises an international centre of heavy ion accelerators that will drive heavy ion and antimatter research. FAIR will provide worldwide unique accelerator and experimental facilities, allowing a large variety of fore-front research in physics and applied science. FAIR will deliver antiproton and ion beams of unprecedented intensities and qualities. The main part of the FAIR facility is a sophisticated accelerator system, which delivers beams to different experiments of the FAIR experimental collaborations - APPA, NuSTAR, CBM and PANDA - in parallel. Modern H-type cavities offer highest shunt impedances of resonant structures of heavy ion linacs at low beam energies < 20 MeV/u and enable the acceleration of intense proton and ion beams. One example is the interdigital H-type structure. The crossed-bar H-cavities extend these properties to high energies even beyond 100 MeV/u. Compared to conventional Alvarez cavities, these crossed-bar (CH) cavities feature much higher shunt impedance at low energies. The design of the proton linac is based on those cavities

Preliminary Characterization of the O4+ Beam in Linac 3

CERN Document Server

Dumas, L; Scrivens, R; CERN. Geneva. AB Department

2007-01-01

The new GTS-LHC ECR ion source was installed in 2005. An oxygen 4+ beam was delivered to LEIR both for injection line (June 2005) and for the ring commissioning (September to December 2005). During these runs, studies were made of the beam transport in the Linac and towards LEIR. Some of the most significant results concerning the Linac are presented in this report. From 2006 the ECR source and the Linac3 delivered a lead beam for the LEIR commissioning, leaving some questions open for the oxygen beam transport. This report serves as a summary of the status of the investigations on the oxygen beam.

Upgrading biogas by a low-temperature CO2 removal techni

Directory of Open Access Journals (Sweden)

Ahmed M.I. Yousef

2016-06-01

Full Text Available Biogas, a renewable energy source, is primarily composed of methane and carbon dioxide and other gaseous species. Biogas upgrading for removing CO2 from raw biogas is a necessary step before the biogas to be used as vehicle fuel or injected into the natural gas grid. Therefore, the present work aimed to propose a low-temperature CO2 removal process as an alternative to the conventional biogas upgrading technologies (water scrubbing, chemical and physical scrubbing, membranes and Pressure swing adsorption. A typical model biogas mixture of 60 mol.% CH4 and 40 mol.% CO2 is considered. The present process showed that a product purity of 94.5 mol.% CH4 is obtained from compressed biogas by combining distillation, flash separation, auxiliary refrigeration and internal heat recovery with a potential specific energy consumption of 0.26 kW h/Nm3 raw biogas. The process has been simulated in Aspen HYSYS with avoiding the occurrence of CO2 freeze-out. The process delivers the captured CO2 in liquid form with a purity of 99.7 mol.% as a by-product for transport at 110 bar. It is concluded that the proposed upgrading process can serve as a new environmentally friendly approach to CO2 removal with an interesting energy-efficient alternative to the conventional upgrading techniques.

Linac 1 in the process of being pulled back

CERN Multimedia

Photographic Service; CERN PhotoLab

1985-01-01

As injector to the PS Booster, Linac 1 was replaced by Linac 2 in 1980. It continued to be used for the acceleration of oxygen and sulfur ions and, from 1981 to 1996, of protons and negative hydrogen ions for LEAR. In 1984, its Cockcroft-Walton preinjector was replaced by a much smaller RFQ, which allowed it to be moved to a more convenient location.

Vibrational Stability of NLC Linac and Final Focus Components

Energy Technology Data Exchange (ETDEWEB)

Le Pimpec, Frederic

2002-09-25

Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structure and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. Design to properly decouple the structure vibrations from the linac quadrupoles is being pursued.

Design of a control system of the linac for SPring-8

International Nuclear Information System (INIS)

Yoshikawa, H.; Itoh, Y.; Kumahara, T.

1992-01-01

The design of a control system of the linac which is a large scale system including many unstable components like klystrons and modulators. The linac for SPring-8 requires to be operated automatically for injection to the synchrotron. Under these conditions, we chose a distributed control system architecture of a single layer net-work to simplify the protocol of the net-work between the linac, the booster synchrotron and the storage ring. A VME computer of 68030 is put in every modulator of the linac, and all control signals are gathered to the nearest VME computer. OS-9 and OS-9000 are on trial for investigation of the performances. TCP/IP is tentatively chosen as a protocol of the net-work, but we expect that MAP/MMS makes a high performance, and we are preparing a test of it. (author)

Proton linac for hospital-based fast neutron therapy and radioisotope production

International Nuclear Information System (INIS)

Lennox, A.J.; Hendrickson, F.R.; Swenson, D.A.; Winje, R.A.; Young, D.E.

1989-09-01

Recent developments in linac technology have led to the design of a hospital-based proton linac for fast neutron therapy. The 180 microamp average current allows beam to be diverted for radioisotope production during treatments while maintaining an acceptable dose rate. During dedicated operation, dose rates greater than 280 neutron rads per minute are achievable at depth, DMAX = 1.6 cm with source to axis distance, SAD = 190 cm. Maximum machine energy is 70 MeV and several intermediate energies are available for optimizing production of isotopes for Positron Emission Tomography and other medical applications. The linac can be used to produce a horizontal or a gantry can be added to the downstream end of the linac for conventional patient positioning. The 70 MeV protons can also be used for proton therapy for ocular melanomas. 17 refs., 1 fig., 1 tab

The new Linac moves mountains

CERN Multimedia

2008-01-01

The civil engineering work has started for Linac 4, one of the major renovation projects for the CERN accelerator complex. The work will be completed at the end of 2010 and the new linear accelerator is scheduled to be commissioned in 2013.

A new irradiation unit constructed of self-moving gantry-CT and linac

International Nuclear Information System (INIS)

Kuriyama, Kengo; Onishi, Hiroshi; Sano, Naoki; Komiyama, Takafumi; Aikawa, Yoshihito; Tateda, Yoshihito; Araki, Tsutomu; Uematsu, Minoru

2003-01-01

Purpose: To improve reproducibility in stereotactic irradiation (STI) without using noninvasive immobilization devices or body frames, we have developed an integrated computed tomography (CT)-linac irradiation system connecting CT scanner and linac via a common treatment couch. Methods and Materials: This system consists of a linac, a CT scanner, and a common treatment couch. The linac and the CT gantry are positioned on opposite ends of the couch so that, by rotating the treatment couch, linac radiotherapy or CT scanning can be performed. The rotational axis of the linac gantry is coaxial with that of the CT gantry, and the position of the linac isocenter on the couch matches the origin of the coordinate system for CT scanning when the couch is rotated 180 degree sign toward the CT side. Instead of the couch moving into the gantry, as in conventional CT, in this case the table is fixed and scanning is accomplished by moving the gantry. We evaluated the rotational accuracy of the common couch and the scan-position accuracy of the self-moving gantry CT. Results: The positional accuracy of the common couch was 0.20, 0.18, and 0.39 mm in the lateral, longitudinal, and vertical directions, respectively. The scan-position accuracy of the CT gantry was less than 0.4 mm in the lateral, longitudinal, and vertical directions. Conclusion: This irradiation system has a high accuracy and is useful for noninvasive STI and for verification of the position of a target in three-dimensional conformal radiotherapy

Status and experiece with the alignment of Linac4

CERN Document Server

Fuchs, Jean-Frederic

2016-01-01

LINAC4 (L4) is an H- linear accelerator that will deliver, for the High Luminosity LHC (HL-LHC) project requirements, a beam of protons at 160 MeV energy to the PS complex and then to the LHC. Its connection to the PS booster will take place during the Long Shutdown 2 (LS2) in 2019-2020 or earlier if any major failure of the LINAC2. The Linac4 project requires the precise alignment with a tolerance of about +/- 0.2 mm in both the horizontal and vertical planes, of elements along approximately 150 m beam line. This paper will give a status, an overview of the challenges of the alignment, the issues solved by the survey section, the techniques and methodology used to realise the survey activities over the last five years.

Design of the SLC damping ring to linac transport lines

International Nuclear Information System (INIS)

Fieguth, T.H.; Murray, J.J.

1983-07-01

The first and second order optics for the damping ring to linac transport line are designed to preserve the damped transverse emittance while simultaneously compressing the bunch length of the beam to that length required for reinjection into the linac. This design, including provisions for future control of beam polarization, is described

Thirty-five years of drift-tube linac experience

International Nuclear Information System (INIS)

Knowles, H.B.

1984-10-01

The history of the drift-tube linear accelerator (linac) for the first 35 years of its existence is briefly reviewed. Both US and foreign experience is included. Particular attention is given to technological improvements, operational reliability, capital investment, and number of personnel committed to drift-tube linac (DTL) development. Preliminary data indicate that second- and third-generation (post-1960) DTLs have, in the US alone, operated for a combined total period of more than 75 machine-years and that very high reliability (>90%) has been achieved. Existing US drift-tube linacs represent a capital investment of at least $250 million (1983). Additional statistical evidence, derived from the proceedings of the last 11 linear accelerator conferences, supports the view that the DTL has achieved a mature technological base. The report concludes with a discussion of important recent advances in technology and their applications to the fourth generation of DTLs, many of which are now becoming operational

Effects Of Field Distortions In Ih-apf Linac

CERN Document Server

Kapin, Valery; Yamada, S

2004-01-01

The project on developing compact medical accelera-tors for the tumor therapy using carbon ions has been started at the National Institute of Radiological Sciences (NIRS). Alternating-phase-focused (APF) linac using an interdigital H-mode (IH) cavity has been proposed for the injector linac. The IH-cavity is doubly ridged circular resonator loaded by the drift-tubes mounted on ridges with supporting stems. The effects of intrinsic and random field distortions in a practical design of the 4-MeV/u 200 MHz IH-APF linac are considered. The intrinsic field distortions in IH-cavity are caused by the asymmetry of the gap field due to presence of the drift-tube supporting stems and pair of ridges. The random field distortions are caused by drift-tube misalignments and non-regular deviations of the voltage distribution from programmed law. The RF fields in IH-cavity have been calculated using Microwave Studio (MWS) code. The effects of field distortions on beam dynamics have been simulated numerically.

Configuring the SLC linac for injection into PEP

International Nuclear Information System (INIS)

Bane, K.L.F.

1989-01-01

From time to time the normal SLC physics program is to be interrupted so that beam can be delivered to PEP. In order that the switch to PEP injection (and the switch back again) can be accomplished quickly and easily, the gun, the damping rings, the linac phase ramp, the energy profile of the linac klystrons for the scavenger bunch, and the entire positron production system are to be kept the same as in the SLC configuration. What mainly remains to be changed is the linac klystron profile for the leading two bunches - those going to PEP. The new klystron profile must be such that it leaves these two beams (1) with final energies that match that of the storage ring and (2) with final energy spectra that fit within the energy aperture of the PEP transfer line. The conditions that need to be met in order to achieve these two goals are discussed in this note. 1 ref., 2 figs

Electron linac design for pion radiotherapy

International Nuclear Information System (INIS)

Loew, G.A.; Brown, K.L.; Miller, R.H.; Walz, D.R.

1977-03-01

The electron linac provides a straightforward, state-of-the-art method of producing the primary beam required for a hospital-based multiport pion radiotherapy facility for cancer treatment. The accelerator and associated beam transport system described are capable of generating an electron beam of about 250 kW and delivering it alternately to one of several pion generators and treatment areas. Each pion generator, a prototype of which now exists at the Stanford W. W. Hansen Laboratory, would contain a target for the electron beam and sixty separate superconducting magnet channels which focus the pions in the patient. The considerations which enter the design of a practical linac are presented together with a possible layout of a flexible beam transport system

Low-energy linac structure for PIGMI

International Nuclear Information System (INIS)

Swenson, D.A.; Stovall, J.E.

1977-01-01

The higher radio frequency (450 MHz) and lower injection energy (250 keV) of the PIGMI (Pion Generator for Medical Irradiations) linac design seriously compound the problem of beam containment in the first few meters of the structure. The conventional quadrupole-focused, drift-tube linac represents the best solution for beam energies above 8 MeV, but because of the small space available for quadrupoles in the PIGMI designs, cannot provide the required focusing at lower energies. A satisfactory solution to this focusing problem has been found based on pure alternating phase focusing for the first few MeV, followed by a smooth transition to a pure permanent magnet quadrupole-focused structure at 8 MeV. The structure and its calculated performance are described

Operational experience with the Fermilab Linac

International Nuclear Information System (INIS)

Allen, L.J.; Lennox, A.J.; Schmidt, C.W.

1992-01-01

The Fermilab 200-MeV Linac has been in operation for nearly 22 years as a proton injector to the Booster synchrotron. It presently accelerates H - ions to 200 MeV for charge-exchange injection into the Booster and to 66 MeV for the production of neutrons at the Neutron Therapy Facility (NTF). The beam intensity is typically 35 mA with pulse widths of 30 μsec for the Booster for high energy physics and 57 μsec for NTF at a maximum of 15 pulses per sec. During a typical physics run of nine to twelve months, beam is available for greater than 98% of the scheduled time. The Linac history, operation, tuning, stability and reliability will be discussed. (Author) 15 refs., 2 tabs

Re-circulating linac vacuum system

International Nuclear Information System (INIS)

Wells, Russell P.; Corlett, John N.; Zholents, Alexander A.

2003-01-01

The vacuum system for a proposed 2.5 GeV, 10ΜA recirculating linac synchrotron light source [1] is readily achievable with conventional vacuum hardware and established fabrication processes. Some of the difficult technical challenges associated with synchrotron light source storage rings are sidestepped by the relatively low beam current and short beam lifetime requirements of a re-circulating linac. This minimal lifetime requirement leads directly to relatively high limits on the background gas pressure through much of the facility. The 10ΜA average beam current produces very little synchrotron radiation induced gas desorption and thus the need for an ante-chamber in the vacuum chamber is eliminated. In the arc bend magnets, and the insertion devices, the vacuum chamber dimensions can be selected to balance the coherent synchrotron radiation and resistive wall wakefield effects, while maintaining the modest limits on the gas pressure and minimal outgassing

Experience with the upgraded VERONA-u WWER-440 core monitoring system

International Nuclear Information System (INIS)

Lux, I.; Vegh, J.; Adorjan, F.; Buerger, L.

1994-01-01

The paper describes the components, functioning and services of the VERONA-u core monitoring system recently installed at Unit 2 and 3 of the Hungarian Paks NPP. The VERONA-u is a totally upgraded and modernized version of the previous VERONA system, in the upgrading project the data-concentrator, the host computer and the operators' displays were replaced by state-of-the-art hardware and software components. Dual hardware redundancy and automatic function recovery actions were introduced in order to ensure high system availability. The man-machine interface has been redesigned completely, applying X Windows as Graphical User Interface. Improved core analysis and power reconstruction methods were introduced, together with a detailed hot-spot monitoring algorithm. A capable archivation module ensures periodic logging of all measured data, change sensitive storage of important signal changes and provides sophisticated post-mortem analysis tools. The upgraded system has been working satisfactorily on Unit 2 for a complete fuel cycle by now, the on-line system response in complex, transient situations is illustrated in the paper. (author). 10 refs, 4 figs

Present status of cryogenic system for e-linac at VECC

International Nuclear Information System (INIS)

Ahammed, Manir; Mondal, Manas; Pal, Sandip; Duttagupta, Anjan; Bandyopadhyay, Arup; Naik, Vaishali; Chakrabarti, Alok; Laxdal, Robert E.; Koveshnikov, Alexy

2015-01-01

VECC is constructing a 50 MeV, 100 kW, superconducting electron linear accelerator (e-Linac) for the upcoming ANURIB (Advanced National facility for Unstable and Rare Isotope Beams) project at the new campus. Presently a 10 MeV injector for the e-Linac is being developed in collaboration with TRIUMF laboratory in Canada.The Injector comprises a 300 kV electron gun, low energy beam transport (LEBT) line and an injector cryo-module (ICM) that houses one 9-cell beta=1, 1.3 GHz niobium elliptical cavity operated at 2K. Alternatively, a capture cryo-module (CCM) having two single cell beta=1, 1.3 GHz niobium cavities that will allow the electron gun to be operated at 100 kV is also being developed. The e-Linac has been jointly designed by VECC and TRIUMF. The ICM is being built by TRIUMF whereas front-end of the injector is being built indigenously at VECC. In this report the details and present status of the cryogenic system for the e-Linac will be presented

H- ion sources for CERN's Linac4

Science.gov (United States)

Lettry, J.; Aguglia, D.; Coutron, Y.; Chaudet, E.; Dallocchio, A.; Gil Flores, J.; Hansen, J.; Mahner, E.; Mathot, S.; Mattei, S.; Midttun, O.; Moyret, P.; Nisbet, D.; O'Neil, M.; Paoluzzi, M.; Pasquino, C.; Pereira, H.; Arias, J. Sanchez; Schmitzer, C.; Scrivens, R.; Steyaert, D.

2013-02-01

The specifications set to the Linac4 ion source are: H- ion pulses of 0.5 ms duration, 80 mA intensity and 45 keV energy within a normalized emittance of 0.25 mmmrad RMS at a repetition rate of 2 Hz. In 2010, during the commissioning of a prototype based on H- production from the plasma volume, it was observed that the powerful co-extracted electron beam inherent to this type of ion source could destroy its electron beam dump well before reaching nominal parameters. However, the same source was able to provide 80 mA of protons mixed with a small fraction of H2+ and H3+ molecular ions. The commissioning of the radio frequency quadrupole accelerator (RFQ), beam chopper and H- beam diagnostics of the Linac4 are scheduled for 2012 and its final installation in the underground building is to start in 2013. Therefore, a crash program was launched in 2010 and reviewed in 2011 aiming at keeping the original Linac4 schedule with the following deliverables: Design and production of a volume ion source prototype suitable for 20-30 mA H- and 80 mA proton pulses at 45 keV by mid-2012. This first prototype will be dedicated to the commissioning of the low energy components of the Linac4. Design and production of a second prototype suitable for 40-50 mA H- based on an external RF solenoid plasma heating and cesiated-surface production mechanism in 2013 and a third prototype based on BNL's Magnetron aiming at reliable 2 Hz and 80 mA H- operations in 2014. In order to ease the future maintenance and allow operation with Ion sources based on three different production principles, an ion source "front end" providing alignment features, pulsed gas injection, pumping units, beam tuning capabilities and pulsed bipolar high voltage acceleration was designed and is being produced. This paper describes the progress of the Linac4 ion source program, the design of the Front end and first ion source prototype. Preliminary results of the summer 2012 commissioning are presented. The outlook on

Ultrafast harmonic rf kicker design and beam dynamics analysis for an energy recovery linac based electron circulator cooler ring

Directory of Open Access Journals (Sweden)

Yulu Huang

2016-08-01

Full Text Available An ultrafast kicker system is being developed for the energy recovery linac (ERL based electron circulator cooler ring (CCR in the proposed Jefferson Lab Electron Ion Collider (JLEIC, previously named MEIC. In the CCR, the injected electron bunches can be recirculated while performing ion cooling for 10–30 turns before the extraction, thus reducing the recirculation beam current in the ERL to 1/10−1/30 (150  mA-50  mA of the cooling beam current (up to 1.5 A. Assuming a bunch repetition rate of 476.3 MHz and a recirculating factor of 10 in the CCR, the kicker is required to operate at a pulse repetition rate of 47.63 MHz with pulse width of around 2 ns, so that only every 10th bunch in the CCR will experience a transverse kick while the rest of the bunches will not be disturbed. Such a kicker pulse can be synthesized by ten harmonic modes of the 47.63 MHz kicker pulse repetition frequency, using up to four quarter wavelength resonator (QWR based deflecting cavities. In this paper, several methods to synthesize such a kicker waveform will be discussed and a comparison of their beam dynamics performance is made using ELEGANT. Four QWR cavities are envisaged with high transverse shunt impedance requiring less than 100 W of total rf power for a Flat-Top kick pulse. Multipole fields due to the asymmetry of this type of cavity are analyzed. The transverse emittance growth due to the sextupole component is simulated in ELEGANT. Off-axis injection and extraction issues and beam optics using a multicavity kick-drift scheme will also be discussed.

Linac boosters for electrostatic machines

International Nuclear Information System (INIS)

Ben-Zvi, I.; Brookhaven National Lab., Upton, NY

1990-01-01

A survey of linacs which are used as boosters to electrostatic accelerators is presented. Machines both operating and under construction, copper and superconducting, are reviewed. The review includes data on the accelerating structures, performance, rf and control, beam optics, budget, vacuum and cryogenics. (orig.)

IRLED-based patient localization for linac radiosurgery

International Nuclear Information System (INIS)

Meeks, Sanford L.; Bova, Francis J.; Friedman, William A.; Buatti, John M.; Moore, Russell D.; Mendenhall, William M.

1998-01-01

Purpose: Currently, precise stereotactic radiosurgery delivery is possible with the Gamma Knife or floor-stand linear accelerator (linac) systems. Couch-mounted linac radiosurgery systems, while less expensive and more flexible than other radiosurgery delivery systems, have not demonstrated a comparable level of precision. This article reports on the development and testing of an optically guided positioning system designed to improve the precision of patient localization in couch-mounted linac radiosurgery systems. Methods and Materials: The optically guided positioning system relies on detection of infrared light-emitting diodes (IRLEDs) attached to a standard target positioner. The IRLEDs are monitored by a commercially available camera system that is interfaced to a personal computer. An IRLED reference is established at the center of stereotactic space, and the computer reports the current position of the IRLEDs relative to this reference position. Using this readout from the computer, the correct stereotactic coordinate can be set directly. Results: Bench testing was performed to compare the accuracy of the optically guided system with that of a floor-stand system, that can be considered an absolute reference. This testing showed that coordinate localization using the IRLED system to track translations agreed with the absolute to within 0.1 ± 0.1 mm. As rotations for noncoplanar couch angles were included, the inaccuracy was increased to 0.2 ± 0.1 mm. Conclusions: IRLED technology improves the accuracy of patient localization relative to the linac isocenter in comparison with conventional couch-mounted systems. Further, the patient's position can be monitored in real time as the couch is rotated for all treatment angles. Thus, any errors introduced by couch inaccuracies can be detected and corrected

Parallel Beam Dynamics Simulation Tools for Future Light Source Linac Modeling

International Nuclear Information System (INIS)

Qiang, Ji; Pogorelov, Ilya v.; Ryne, Robert D.

2007-01-01

Large-scale modeling on parallel computers is playing an increasingly important role in the design of future light sources. Such modeling provides a means to accurately and efficiently explore issues such as limits to beam brightness, emittance preservation, the growth of instabilities, etc. Recently the IMPACT codes suite was enhanced to be applicable to future light source design. Simulations with IMPACT-Z were performed using up to one billion simulation particles for the main linac of a future light source to study the microbunching instability. Combined with the time domain code IMPACT-T, it is now possible to perform large-scale start-to-end linac simulations for future light sources, including the injector, main linac, chicanes, and transfer lines. In this paper we provide an overview of the IMPACT code suite, its key capabilities, and recent enhancements pertinent to accelerator modeling for future linac-based light sources

Parameters of the preproduction series SiPMs for the CMS HCAL phase I upgrade

Energy Technology Data Exchange (ETDEWEB)

Heering, A., E-mail: Adriaan.Heering@cern.ch [University of Notre Dame, Notre Dame, IN 46556 (United States); Musienko, Yu., E-mail: Iouri.Musienko@cern.ch [University of Notre Dame, Notre Dame, IN 46556 (United States); Institute for Nuclear Research RAS, pr. 60-letiya Oktyabrya 7a, 117312 Moscow (Russian Federation); Ruchti, R.; Wayne, M. [University of Notre Dame, Notre Dame, IN 46556 (United States); Karneyeu, A.; Postoev, V. [Institute for Nuclear Research RAS, pr. 60-letiya Oktyabrya 7a, 117312 Moscow (Russian Federation)

2016-07-11

In 2012 the HCAL SiPM photo sensor upgrade was approved for the increased luminosity (5*10{sup 34}) of SLHC. The upgrade will replace the current hybrid photodiodes (HPDs) with multi-pixel Geiger-mode avalanche photodiodes, also known as silicon photomultipliers (SiPMs). A key aspect of the upgrade to SiPMs is to add longitudinal segmentation and improve signal to noise to compensate for scintillator radiation damage. After 5 years of R&D with multiple companies we developed custom large dynamic range SiPMs with large PDE and small ENC. To ensure good mechanical alignment and easy handling of the large number of production channels (>20,000) we have developed a custom ceramic package with a very thin 0.3 mm quartz window with Kyocera. Each package holds 8 channels of SiPMs. Here we report on the final SiPM parameters of the 2014 preproduction run from Hamamatsu (HPK) who has produced a series of 175 arrays with a total of 1400 SiPMs. An overview of our QA results and measurements of the photon detection efficiency, spectral response, crosstalk and cell recovery time will be discussed. - Highlights: • Uniformity of large scale SiPM production. • Small cell size SiPMs with high photo detection efficiency. • Fast recovery time SiPMs. • Custom packaging of SiPMs in High Energy Physics experiments.

Characteristics of short pulse grid pulser for an electron LINAC

International Nuclear Information System (INIS)

Wang Guicheng; Fang Zhigao; Hong Jun

1996-01-01

An equivalent circuit is used to obtain the output waveform of a short pulse grid pulser for an electron LINAC, and the amplitude of the output pulse is studied as a function of number of switching transistors for some kinds of transistor. Two pulsers were fabricated to fulfill the requirements of the 200 MeV LINAC at NSRL

LINAC-radiosurgery for nonsecreting pituitary adenomas. Long-term results

Energy Technology Data Exchange (ETDEWEB)

Runge, M.J.R.; Maarouf, M.; Hunsche, S.; Ruge, M.I.; El Majdoub, F.; Treuer, H.; Sturm, V. [Koeln Univ. (Germany). Dept. of Stereotaxy and Functional Neurosurgery; Kocher, M.; Mueller, R.P. [Koeln Univ. (Germany). Dept. of Radiation Oncology; Voges, J. [Magdeburg Univ. (Germany). Dept. of Stereotactic Neurosurgery

2012-04-15

Stereotactic linear accelerator-based radiosurgery (LINAC-RS) is increasingly used for microsurgically inaccessible or recurrent pituitary adenomas. This single-center study evaluates the long-term follow-up after LINAC-RS of nonsecreting pituitary adenomas (NSA). Patients and methods: Between 1992 and August 2008, 65 patients with NSA were treated. Patient treatment and follow-up were conducted according to a prospective protocol. Indications for LINAC-RS were (1) tumor recurrence or (2) residual tumor. Three patients were treated primarily. For analysis of prognostic factors, patients were grouped according to epidemiological or treatment-associated characteristics. Results: A total of 61 patients with a follow-up {>=} 12 months (median 83 months, range 15-186 months, longest follow-up of published radiosurgery series) were evaluated with regard to their clinical, radiological, and endocrinological course. The median tumor volume was 3.5 ml ({+-} 4.3 ml, range 0.3-17.3 ml) treated with a median surface and maximum dose of 13.0 Gy and 29.7 Gy, respectively. Local tumor control was achieved in 98%. One patient died of unrelated cause after 36 months and 1 patient developed a radiation-induced seizure disorder. Visual complications did not occur. In 37 of 41 patients (90.2%), pituitary function remained stable. Maximum dose to the pituitary {<=} 16 Gy and female gender were positive prognostic factors for the preservation of pituitary function. Conclusion: LINAC-RS is a minimally invasive, safe, and effective treatment for recurrent NSA or microsurgically inaccessible residual tumor. LINAC-RS yielded a high rate of local long-term tumor control with a small number of radiation-induced side effects. (orig.)

LINAC-radiosurgery for nonsecreting pituitary adenomas. Long-term results

International Nuclear Information System (INIS)

Runge, M.J.R.; Maarouf, M.; Hunsche, S.; Ruge, M.I.; El Majdoub, F.; Treuer, H.; Sturm, V.; Kocher, M.; Mueller, R.P.; Voges, J.

2012-01-01

Stereotactic linear accelerator-based radiosurgery (LINAC-RS) is increasingly used for microsurgically inaccessible or recurrent pituitary adenomas. This single-center study evaluates the long-term follow-up after LINAC-RS of nonsecreting pituitary adenomas (NSA). Patients and methods: Between 1992 and August 2008, 65 patients with NSA were treated. Patient treatment and follow-up were conducted according to a prospective protocol. Indications for LINAC-RS were (1) tumor recurrence or (2) residual tumor. Three patients were treated primarily. For analysis of prognostic factors, patients were grouped according to epidemiological or treatment-associated characteristics. Results: A total of 61 patients with a follow-up ≥ 12 months (median 83 months, range 15-186 months, longest follow-up of published radiosurgery series) were evaluated with regard to their clinical, radiological, and endocrinological course. The median tumor volume was 3.5 ml (± 4.3 ml, range 0.3-17.3 ml) treated with a median surface and maximum dose of 13.0 Gy and 29.7 Gy, respectively. Local tumor control was achieved in 98%. One patient died of unrelated cause after 36 months and 1 patient developed a radiation-induced seizure disorder. Visual complications did not occur. In 37 of 41 patients (90.2%), pituitary function remained stable. Maximum dose to the pituitary ≤ 16 Gy and female gender were positive prognostic factors for the preservation of pituitary function. Conclusion: LINAC-RS is a minimally invasive, safe, and effective treatment for recurrent NSA or microsurgically inaccessible residual tumor. LINAC-RS yielded a high rate of local long-term tumor control with a small number of radiation-induced side effects. (orig.)

Upgraded phase control system for superconducting low-velocity accelerating structures

Energy Technology Data Exchange (ETDEWEB)

Added, N [Sao Paulo Univ., SP (Brazil); Clifft, B E; Shepard, K W [Argonne National Lab., IL (United States)

1992-11-01

Microphonic-induced fluctuations in the RF eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the RF phase. The tuning system must handle a reactive power proportional to the product of the frequency range and the RF energy content of the RF cavity. The fast tuner for the SC resonators in the ATLAS heavy-ion linac is a voltage-controlled reactance based on an array of PIN diodes operating immersed in liquid nitrogen. This paper discusses recent upgrades to the ATLAS fast tuner which can now provide as much as 30 KVA of reactive tuning capability with a real RF power loss of less than 300 watts. The design was guided by numerical modeling of all elements of the device. Also discussed is the RF coupler which can couple 30 KW from 77 K tuner to a 4.2 K resonant cavity with less than 2 W of RF loss into 4.2 K. (Author) 6 refs., 2 figs.

Upgraded phase control system for superconducting low-velocity accelerating structures

International Nuclear Information System (INIS)

Added, N.; Clifft, B.E.; Shepard, K.W.

1992-01-01

Microphonic-induced fluctuations in the RF eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the RF phase. The tuning system must handle a reactive power proportional to the product of the frequency range and the RF energy content of the RF cavity. The fast tuner for the SC resonators in the ATLAS heavy-ion linac is a voltage-controlled reactance based on an array of PIN diodes operating immersed in liquid nitrogen. This paper discusses recent upgrades to the ATLAS fast tuner which can now provide as much as 30 KVA of reactive tuning capability with a real RF power loss of less than 300 watts. The design was guided by numerical modeling of all elements of the device. Also discussed is the RF coupler which can couple 30 KW from 77 K tuner to a 4.2 K resonant cavity with less than 2 W of RF loss into 4.2 K. (Author) 6 refs., 2 figs

Status of the SNS superconducting linac and future plan

International Nuclear Information System (INIS)

Kim, Sang-Ho

2008-01-01

The use of superconducting radiofrequency (SRF) cavities in particle accelerator is becoming more widespread. Among the projects that make use of that technology is the Spallation Neutron Source, where H- ions are accelerated to about 1 GeV, mostly making use of niobium elliptical cavities. SNS generates neutrons by the spallation reaction with the accelerated short (about 700 ns) sub-bunches of protons, which will in turn allow probing structural and magnetic properties of new and existing materials. The SNS superconducting linac is the largest application of RF superconductivity to come on-line in the last decade and has been operating with beam for almost two years. As the first operational pulsed superconducting linac, many of the aspects of its performance were unknown and unpredictable. A lot of experiences and data have been gathered on the pulsed behavior of cavities and cryomodules at various repetition rates and at various temperatures during the commissioning of its components and beam operations. This experience is of great value in determining future optimizations of SNS as well in guiding in the design and operation of future pulsed superconducting linacs. The testing of the superconducting cavities, the operating experience with beam, the performance of the superconducting linac and the future plans will be presented.

Emittance and trajectory control in the main linacs of the NLC

International Nuclear Information System (INIS)

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

1996-09-01

The main linacs of the next generation of linear colliders need to accelerate the particle beams to energies of up to 750 GeV while maintaining very small emittances. This paper describes the main mechanisms of static emittance growth in the main linacs of the Next Linear Collider (NLC). The authors present detailed simulations of the trajectory and emittance control algorithms that are foreseen for the NLC. They show that the emittance growth in the main linacs can be corrected down to about 110%. That number is significantly better than required for the NLC design luminosity

Basis for low beam loss in the high-current APT linac

International Nuclear Information System (INIS)

Wangler, T.P.; Gray, E.R.; Krawczyk, F.L.; Kurennoy, S.S.; Lawrence, G.P.; Ryne, R.D.; Crandall, K.R.

1998-01-01

The present evidence that the APT proton linac design will meet its goal of low beam loss operation. The conclusion has three main bases: (1) extrapolation from the understanding of the performance of the 800-MeV LANSCE proton linac at Los Alamos, (2) the theoretical understanding of the dominant halo-forming mechanism in the APT accelerator from physics models and multiparticle simulations, and (3) the conservative approach and key principles underlying the design of the APT linac, which are aimed at minimizing beam halo and providing large apertures to reduce beam loss to a very low value

Technical Note: Development and performance of a software tool for quality assurance of online replanning with a conventional Linac or MR-Linac

Energy Technology Data Exchange (ETDEWEB)

Chen, Guang-Pei, E-mail: gpchen@mcw.edu; Ahunbay, Ergun; Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 (United States)

2016-04-15

Purpose: To develop an integrated quality assurance (QA) software tool for online replanning capable of efficiently and automatically checking radiation treatment (RT) planning parameters and gross plan quality, verifying treatment plan data transfer from treatment planning system (TPS) to record and verify (R&V) system, performing a secondary monitor unit (MU) calculation with or without a presence of a magnetic field from MR-Linac, and validating the delivery record consistency with the plan. Methods: The software tool, named ArtQA, was developed to obtain and compare plan and treatment parameters from both the TPS and the R&V system database. The TPS data are accessed via direct file reading and the R&V data are retrieved via open database connectivity and structured query language. Plan quality is evaluated with both the logical consistency of planning parameters and the achieved dose–volume histograms. Beams in between the TPS and R&V system are matched based on geometry configurations. To consider the effect of a 1.5 T transverse magnetic field from MR-Linac in the secondary MU calculation, a method based on modified Clarkson integration algorithm was developed and tested for a series of clinical situations. Results: ArtQA has been used in their clinic and can quickly detect inconsistencies and deviations in the entire RT planning process. With the use of the ArtQA tool, the efficiency for plan check including plan quality, data transfer, and delivery check can be improved by at least 60%. The newly developed independent MU calculation tool for MR-Linac reduces the difference between the plan and calculated MUs by 10%. Conclusions: The software tool ArtQA can be used to perform a comprehensive QA check from planning to delivery with conventional Linac or MR-Linac and is an essential tool for online replanning where the QA check needs to be performed rapidly.

Technical Note: Development and performance of a software tool for quality assurance of online replanning with a conventional Linac or MR-Linac.

Science.gov (United States)

Chen, Guang-Pei; Ahunbay, Ergun; Li, X Allen

2016-04-01

To develop an integrated quality assurance (QA) software tool for online replanning capable of efficiently and automatically checking radiation treatment (RT) planning parameters and gross plan quality, verifying treatment plan data transfer from treatment planning system (TPS) to record and verify (R&V) system, performing a secondary monitor unit (MU) calculation with or without a presence of a magnetic field from MR-Linac, and validating the delivery record consistency with the plan. The software tool, named ArtQA, was developed to obtain and compare plan and treatment parameters from both the TPS and the R&V system database. The TPS data are accessed via direct file reading and the R&V data are retrieved via open database connectivity and structured query language. Plan quality is evaluated with both the logical consistency of planning parameters and the achieved dose-volume histograms. Beams in between the TPS and R&V system are matched based on geometry configurations. To consider the effect of a 1.5 T transverse magnetic field from MR-Linac in the secondary MU calculation, a method based on modified Clarkson integration algorithm was developed and tested for a series of clinical situations. ArtQA has been used in their clinic and can quickly detect inconsistencies and deviations in the entire RT planning process. With the use of the ArtQA tool, the efficiency for plan check including plan quality, data transfer, and delivery check can be improved by at least 60%. The newly developed independent MU calculation tool for MR-Linac reduces the difference between the plan and calculated MUs by 10%. The software tool ArtQA can be used to perform a comprehensive QA check from planning to delivery with conventional Linac or MR-Linac and is an essential tool for online replanning where the QA check needs to be performed rapidly.

Smooth transverse and longitudinal focusing in high-intensity ion linacs

International Nuclear Information System (INIS)

Billen, J.H.; Takeda, Harunori; Young, L.M.

1996-01-01

We examine ion linac designs that start with a high energy radio- frequency quadrupole (RFQ) followed by either a drift-tube linac (DTL) or a coupled-cavity drift-tube linac (CCDTL). For high energies a conventional CCL follows the CCDTL. High RFQ output energy allows tailoring the transverse and longitudinal focusing strengths to match into the following structure. When the RFQ beam enters a higher frequency structure, the DTL or CCDTL starts with a low accelerating gradient and large negative synchronous phase. The gradient and phase both ramp up gradually to higher values. Other changes later in the machine are also gradual. Beam dynamics simulations show that these linacs require no separate matching sections. Applications include a cw 100 mA H + beam from a 350-MHz, 6.7 MeV RFQ injecting a 700 MHz CCDTL and CCL; a 7% duty 28 mA H - beam from a 402.5 MHz RFQ and DTL injecting 805 MHz structures; a cw 135 mA D + beam produced by a 175 MHz, 8 MeV RFQ and DTL; and a 2.4% duty, 80 mA H + beam using a 433 MHz 10 MeV RFQ and a 1300 MHz CCDTL. The machines take advantage of the considerable flexibility of the CCDTL. Designs can use a variety of different transverse focusing lattices. Use of two coupling cavity orientations permits a constant period even when the number of drift tubes per cavity changes along the linac

Optical modeling of induction-linac driven free-electron lasers

International Nuclear Information System (INIS)

Scharlemann, E.T.; Fawley, W.M.

1986-01-01

The free-electron laser (FEL) simulation code FRED, developed at Lawrence Livermore National Laboratory (LLNL) primarily to model single-pass FEL amplifiers driven by induction linear accelerators, is described. The main emphasis is on the modeling of optical propagation in the laser and on the differences between the requirements for modeling rf-linac-driven vs. induction-linac-driven FELs. Examples of optical guiding and mode cleanup are presented for a 50 μm FEL

Nonlinear space charge effect of bunched beam in linac

International Nuclear Information System (INIS)

Chen Yinbao

1992-02-01

The nonlinear space charge effect due to the nonuniform particle density distribution in bunched beam of a linac is discussed. The formulae of nonlinear space charge effect and nonlinear focusing forces were derived for the bunched beam with Kapchinskij-Vladimirskij (K-V) distribution, waterbag (WB) distribution, parabolic (PA) distribution, and Gauss (GA) distribution in both of the space charge disk model and space charge cylinder model in the waveguide of a linac

Beam position monitor for energy recovered linac beams

Energy Technology Data Exchange (ETDEWEB)

Powers, Thomas; Evtushenko, Pavel

2017-06-06

A method of determining the beam position in an energy recovered linac (ERL). The method makes use of in phase and quadrature (I/Q) demodulation techniques to separate the pickup signal generated by the electromagnetic fields generated by the first and second pass beam in the energy recovered linac. The method includes using analog or digital based I/Q demodulation techniques in order to measure the relative amplitude of the signals from a position sensitive beam pickup such as a button, strip line or microstripline beam position monitor.

Micro-SHINE Uranyl Sulfate Irradiations at the Linac

Energy Technology Data Exchange (ETDEWEB)

Youker, Amanda J. [Argonne National Lab. (ANL), Argonne, IL (United States); Kalensky, Michael [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Schneider, John [Argonne National Lab. (ANL), Argonne, IL (United States); Byrnes, James [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-08-01

Peroxide formation due to water radiolysis in a uranyl sulfate solution is a concern for the SHINE Medical Technologies process in which Mo-99 is generated from the fission of dissolved low enriched uranium. To investigate the effects of power density and fission on peroxide formation and uranyl-peroxide precipitation, uranyl sulfate solutions were irradiated using a 50-MeV electron linac as part of the micro-SHINE experimental setup. Results are given for uranyl sulfate solutions with both high and low enriched uranium irradiated at different linac powers.

Linac-driven spallation-neutron source

International Nuclear Information System (INIS)

Jason, A.J.

1995-01-01

Strong interest has arisen in accelerator-driven spallation-neutron sources that surpass existing facilities (such as ISIS at Rutherford or LANSCE at Los Alamos) by more than an order of magnitude in beam power delivered to the spallation target. The approach chosen by Los Alamos (as well as the European Spallation Source) provides the full beam energy by acceleration in a linac as opposed to primary acceleration in a synchrotron or other circular device. Two modes of neutron production are visualized for the source. A short-pulse mode produces 1 MW of beam power (at 60 pps) in pulses, of length less than 1 ms, by compression of the linac macropulse through multi-turn injection in an accumulator ring. A long-pulse mode produces a similar beam power with 1-ms-long pulses directly applied to a target. This latter mode rivals the performance of existing reactor facilities to very low neutron energies. Combination with the short-pulse mode addresses virtually all applications

Redesign of the low energy section of the Fermilab linac to improve beam brightness

International Nuclear Information System (INIS)

Schmidt, C.; Noble, R.; Palkovic, J.; Mills, F.E.

1988-10-01

The critical parameters which limit the luminosity of the Fermilab Tevatron Collider are the beam emittances, both longitudinal and transverse, at each stage in the acceleration sequence. Improvements to reduce invariant emittance growth at earlier acceleration stages necessarily encourage improvements in all downstream stages. Recent advances in linac technology should permit a significant increase in the beam brightness of the Fermilab linac. A redesign of the low energy section of the linac is envisioned to include a circular aperture H/sup /minus// source, a short 30-keV transport line (solenoids, Gabor lenses or einzel lenses) for matching to a radio frequency quadrupole linac (RFQ), and injection at approximately 2 MeV into a new 200 MHz Alvarez linac tank for acceleration to 10 MeV. 9 refs., 1 fig

Radio-frequency-quadrupole linac in a heavy ion fusion driver system

International Nuclear Information System (INIS)

Hansborough, L.D.; Stokes, R.; Swenson, D.A.; Wangler, T.P.

1980-01-01

A new type of linear accelerator, the radio-frequency quadrupole (RFQ) linac, is being developed for the acceleration of low-velocity ions. The RFQ accelerator can be adapted to any high-current applications. A recent experimental test carried out at the Los Alamos Scienific Laboratory (LASL) has demonstrated the outstandig properties of RFQ systems. The test linac accepts a 30-mA proton beam of 100-keV energy and focuses, bunches, and accelerates the beam to an energy to 640 keV. This ia done in a length of 1.1 m, with a transmission efficiency of 87% and with a radial emittance growth of less than 60%. The proven capability of the RFQ linac, when extended to heavy ion acceleration, should provide an ideal technique for use in the low-velocity portion of a heavy-ion linac for inertial-confinement fusion. A specific concept for such an RFQ-based system is described

The new building for Linac4 is ready ahead of schedule

CERN Multimedia

Francesco Poppi

2010-01-01

When various teams work together efficiently to achieve a common goal, not only are projects successfully completed but they may ever be ready before the deadline. On 22 October, after two years of civil engineering work and about two months ahead of schedule, the building that will host the new Linac4 was unveiled in the presence of the Director-General and of Steve Myers, Director for Accelerators and Technology.   Entrance to new Linac 4 tunnel. For the time being, the new two-storey 3000 m2 building looks like a huge empty hangar. Very soon, though, the ground floor will start to be filled with the technical equipment and the klystrons. The Linac4 itself will be installed in the tunnel excavated below the ground. “Being 12 metres underground, deep inside what remains of the old “Mount Citron”, the tunnel provides excellent shielding for the new accelerator”, says Maurizio Vretenar, Linac4 Project Leader. The tunnel will be connected to the PS Booster...

Operational experience with the control scheme for IUAC linac booster

International Nuclear Information System (INIS)

Sahu, B.K.; Antony, J.; Mathuria, D.S.; Pandey, A.; Ghosh, S.; Mehta, R.; Rai, A.; Patra, P.; Choudhury, G.K.; Singh, K.; Ajith Kumar, B.P.; Kanjilal, D.; Roy, A.

2009-01-01

Accelerated beam from the first superconducting linear accelerator (linac) module of IUAC has been delivered to the user. The linac control scheme has worked successfully with the existing pelletron control scheme. Local RF control system consisting of Resonator controller and supporting RF modules are used for multipactoring conditioning, high power pulse conditioning and for the phase/amplitude locking of the superconducting resonators. Beam acceleration is done by adjusting the RF phase of each resonator with respect to master oscillator. The automation of control scheme is planned for smooth operation of linac with minimum human intervention. Python software support is added for writing automation routines in present control system software. An alternate tuning mechanism based on piezoelectric actuators has been successfully tested. (author)

Gain physics of rf-linac-driven xuv free-electron lasers

International Nuclear Information System (INIS)

Goldstein, J.C.; McVey, B.D.; Newnam, B.E.

1986-01-01

In an rf-linac-driven xuv free-electron laser oscillator, the gain depends on the details of the shape of the electron beam's phase-space distribution, particularly the distribution of electrons in the transverse (to the direction of propagation) position and velocity coordinates. This strong dependence occurs because the gain in this device is inhomogeneously broadened. Our previous theoretical studies have assumed that the transverse phase space distribution is a product of uncorrelated Gaussian functions. In the present work, we shall present the results of a theoretical study of the gain for non-Gaussian phase-space distributions. Such distributions arise either from a better representation of the electron beam from an rf-linac or from an emittance filter applied to the beam after the linac

X-band Linac for a 6 MeV dual-head radiation therapy gantry

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Hyun; Shin, Seung-Wook; Lee, Jongchul; Kim, Hui-Su [WCU Department of Energy Science, Suwon 440-746 (Korea, Republic of); Lee, Byeong-No; Lee, Byung-Chul [Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute, Jeongeup 56212 (Korea, Republic of); Park, Hyung-dal; Song, Ki-back [Radiation Technology eXcellence (RTX), Daejeon 305-500 (Korea, Republic of); Song, Ho-seung; Mun, Sangchul; Ha, Donghyup [School of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Chai, Jong-Seo, E-mail: jschai@skku.edu [School of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

2017-04-21

We developed a design for a 6 MeV X-band linear accelerator for radiation therapy in a dual-head gantry layout. The dual-head gantry has two linacs that can be operated independently. Each X-band linac accelerates electron bunches using high-power RF and generates X-rays for radiation therapy. It requires a versatile RF system and pulse sequence to accomplish various radiation therapy procedures. The RF system consists of 9.3 GHz, 2 MW X-band magnetron and associated RF transmission components. A test linac was assembled and operated to characterize its RF performance without beam. This paper presents these results along with a description of the gantry linacs and their operational requirements.

Status of rf superconductivity at Argonne National Laboratory

International Nuclear Information System (INIS)

Markovich, P.M.; Shepard, K.W.; Zinkann, G.P.

1987-01-01

This paper reports the status of hardware development for the linac portion of the Argonne tandem-linac accelerator system (ATLAS). The ATLAS superconducting linac consists of an independent-phased array of 45 superconducting niobium resonators of the split-ring type. The linac has been operating in its present form since 1985, on a 24-hours per day, 5 days per week schedule. An upgrade of the ATLAS system is currently under construction the positive-ion injector (PII). The PII system will consist of an ECR positive-ion source mounted on a high-voltage platform injecting a very-low-velocity superconducting linac. The completed system will provide for the acceleration of beams of mass up to uranium, and will replace the tandem electrostatic accelerator as the injector for ATLAS. The status of resonator development for the superconducting linac is reported in this paper. Accelerating gradients in the existing ATLAS linac are currently limited by excessive heating and rf loss in the fast-tuning system associated with each superconducting resonator. Development of an upgraded fast-tuning system is also reported here. 7 refs., 5 figs

Passive magnetic shielding in MRI-Linac systems

Science.gov (United States)

Whelan, Brendan; Kolling, Stefan; Oborn, Brad M.; Keall, Paul

2018-04-01

Passive magnetic shielding refers to the use of ferromagnetic materials to redirect magnetic field lines away from vulnerable regions. An application of particular interest to the medical physics community is shielding in MRI systems, especially integrated MRI-linear accelerator (MRI-Linac) systems. In these systems, the goal is not only to minimize the magnetic field in some volume, but also to minimize the impact of the shield on the magnetic fields within the imaging volume of the MRI scanner. In this work, finite element modelling was used to assess the shielding of a side coupled 6 MV linac and resultant heterogeneity induced within the 30 cm diameter of spherical volume (DSV) of a novel 1 Tesla split bore MRI magnet. A number of different shield parameters were investigated; distance between shield and magnet, shield shape, shield thickness, shield length, openings in the shield, number of concentric layers, spacing between each layer, and shield material. Both the in-line and perpendicular MRI-Linac configurations were studied. By modifying the shield shape around the linac from the starting design of an open ended cylinder, the shielding effect was boosted by approximately 70% whilst the impact on the magnet was simultaneously reduced by approximately 10%. Openings in the shield for the RF port and beam exit were substantial sources of field leakage; however it was demonstrated that shielding could be added around these openings to compensate for this leakage. Layering multiple concentric shield shells was highly effective in the perpendicular configuration, but less so for the in-line configuration. Cautious use of high permeability materials such as Mu-metal can greatly increase the shielding performance in some scenarios. In the perpendicular configuration, magnetic shielding was more effective and the impact on the magnet lower compared with the in-line configuration.

Machine Imperfection Studies of the RAON Superconducting Linac

Science.gov (United States)

Jeon, D.; Jang, J.-H.; Jin, H.

2018-05-01

Studies of the machine imperfections in the RAON superconducting linac (SCL) that employs normal conducting (NC) quadrupoles were done to assess the tolerable error budgets of the machine imperfections that ensure operation of the beam. The studies show that the beam loss requirement is met even before the orbit correction and that the beam loss requirement is met even without the MHB (multi-harmonic buncher) and VE (velocity equalizer) thanks to the RAON's radio-frequency quadrupole (RFQ) design feature. For the low energy section of the linac (SCL3), a comparison is made between the two superconducting linac lattice types: one lattice that employs NC quadrupoles and the other that employs SC solenoids. The studies show that both lattices meet the beam loss requirement after the orbit correction. However, before the orbit correction, the lattice employing SC solenoids does not meet the beam loss requirement and can cause a significant beam loss, while the lattice employing NC quadrupoles meets the requirement. For the lattice employing SC solenoids, care must be taken during the beam commissioning.

H- Ion Sources For CERN’s Linac4

CERN Document Server

Lettry, J; Coutron, Y; Chaudeta, E; Dallocchio, A; Gil Flores, J; Hansen, J; Mahner, E; Mathot, S; Mattei, S; Midttun, O; Moyret, P; Nisbet, D; O’Neil, M; Paoluzzi, M; Pasquino, C; Pereira, H; Sanchez Arias, J; Schmitzer, C; Scrivens, R; Steyaert, D

2013-01-01

The specifications set to the Linac4 ion source are: H- ion pulses of 0.5 ms duration, 80 mA intensity and 45 keV energy within a normalized emittance of 0.25 mmmrad RMS at a repetition rate of 2 Hz. In 2010, during the commissioning of a prototype based on H- production from the plasma volume, it was observed that the powerful co-extracted electron beam inherent to this type of ion source could destroy its electron beam dump well before reaching nominal parameters. However, the same source was able to provide 80 mA of protons mixed with a small fraction of H2+ and H3+ molecular ions. The commissioning of the radio frequency quadrupole accelerator (RFQ), beam chopper and H- beam diagnostics of the Linac4 are scheduled for 2012 and its final installation in the underground building is to start in 2013. Therefore, a crash program was launched in 2010 and reviewed in 2011 aiming at keeping the original Linac4 schedule with the following deliverables: Design and production of a volume ion source prototype suitabl...

SU-E-T-270: Optimized Shielding Calculations for Medical Linear Accelerators (LINACs).

Science.gov (United States)

Muhammad, W; Lee, S; Hussain, A

2012-06-01

The purpose of radiation shielding is to reduce the effective equivalent dose from a medical linear accelerator (LINAC) to a point outside the room to a level determined by individual state/international regulations. The study was performed to design LINAC's room for newly planned radiotherapy centers. Optimized shielding calculations were performed for LINACs having maximum photon energy of 20 MV based on NCRP 151. The maximum permissible dose limits were kept 0.04 mSv/week and 0.002 mSv/week for controlled and uncontrolled areas respectively by following ALARA principle. The planned LINAC's room was compared to the already constructed (non-optimized) LINAC's room to evaluate the shielding costs and the other facilities those are directly related to the room design. In the evaluation process it was noted that the non-optimized room size (i.e., 610 × 610 cm 2 or 20 feet × 20 feet) is not suitable for total body irradiation (TBI) although the machine installed inside was having not only the facility of TBI but the license was acquired. By keeping this point in view, the optimized INAC's room size was kept 762 × 762 cm 2. Although, the area of the optimized rooms was greater than the non-planned room (i.e., 762 × 762 cm 2 instead of 610 × 610 cm 2), the shielding cost for the optimized LINAC's rooms was reduced by 15%. When optimized shielding calculations were re-performed for non-optimized shielding room (i.e., keeping room size, occupancy factors, workload etc. same), it was found that the shielding cost may be lower to 41 %. In conclusion, non- optimized LINAC's room can not only put extra financial burden on the hospital but also can cause of some serious issues related to providing health care facilities for patients. © 2012 American Association of Physicists in Medicine.

Performing instrumentation and controls upgrades

International Nuclear Information System (INIS)

Kessler, F. M.; Connell, T. J.; Ryan, M. P.

1992-01-01

I and C upgrades are comprised of a varying range of content, complexity, expansiveness, and criticality. There are common threads in all upgrades which can be simplified by the development of a long term I and C upgrade plan. The development of a such a plan can establish effective ground rules for upgrades, large and small. It can be the basis from which to begin an upgrade evaluation and the standard which is used to compare the degree of compliance of any upgrade regarding the plan or to define the differences from the plan and an individual upgrade. Primary motivation for I and C upgrades are obsolescence and unavailability of spare parts. Numerous other areas of consideration are also involved in an upgrade. Today's technology results in most upgrades largely or totally utilizing digital equipment. The use of digital equipment is fairly new in many I and C applications and requires an elaborate evaluation from functional, qualification, operational, and licensing perspectives as well as others. A well defined upgrade plan developed as a basis for I and C upgrades is a significant start to ensuring an effective upgrade process. Properly developed and implemented, the plan will support I and C upgrade efforts to ensure that the intricacies associated with such tasks eliminate the existing problems which require the upgrade to be performed. The upgrade plan also results in ensuring the maximum benefit from all perspectives of the plant enhancements being carried out and considered for future implementation. Instrumentation and controls aging and replacement are issues of growing importance due to the potential for significant impact on plant operation and efficiency. Obsolescence and unavailability of spare parts are major drivers towards evaluating the cost benefits of upgrading current equipment. In addition to these two primary factors, the advantages of utilizing digital equipment have also become of prime importance when evaluating instrumentation and

A Recirculating Linac-Based Facility for Ultrafast X-Ray Science

International Nuclear Information System (INIS)

Corlett, J. N.; Barletta, W. A.; DeSantis, S.; Doolittle, L.; Fawley, W. M.; Green, M.A.; Heimann, P.; Leone, S.; Lidia, S.; Li, D.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wolski, A.; Zholents, A.; Parmigiani, F.; Placidi, M.; Pirkl, W.; Rimmer, R. A.; Wang, S.

2003-01-01

We present an updated design for a proposed source of ultra-fast synchrotron radiation pulses based on a recirculating superconducting linac [1,2], in particular the incorporation of EUV and soft x-ray production. The project has been named LUX--Linac-based Ultrafast X-ray facility. The source produces intense x-ray pulses with duration of 10-100 fs at a 10 kHz repetition rate, with synchronization of 10's fs, optimized for the study of ultra-fast dynamics. The photon range covers the EUV to hard x-ray spectrum by use of seeded harmonic generation in undulators, and a specialized technique for ultra-short pulse photon production in the 1-10 keV range. High brightness rf photocathodes produce electron bunches which are optimized either for coherent emission in free electron lasers, or to provide a large x/y emittance ration and small vertical emittance which allows for manipulation to produce short-pulse hard x-rays. An injector linac accelerates the beam to 120 MeV, and is followed by f our passes through a 600-720 MeV recirculating linac. We outline the major technical components of the proposed facility

Linac based radiosurgery and stereotactic radiotherapy

International Nuclear Information System (INIS)

Mackie, T.R.

2008-01-01

The following topics were discussed: Definition of stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT); Stereo market; Indications for SRS/SRT; History of linac-based SRS/SRT; Variety of systems; QA for SRS; Localization; and Imaging. (P.A.)

DESIGN AND FABRICATION OF THE BEAM POSITION MONITOR FOR THE PEFP LINAC

Directory of Open Access Journals (Sweden)

HYEOK-JUNG KWON

2013-08-01

Full Text Available The beam position monitor (BPM is an essential component for the PEFP 100-MeV linac's commissioning. A prototype stripline-type linac BPM was designed for this purpose. The electrode aperture is 20 mm in diameter, and the electrode is 25 mm long, so it can be installed between Drift Tube Linac (DTL101 and DTL102, which is the shortest distance. One end of the electrode is connected to the Sub Miniature Type A (SMA feed through for signal measurement, and the other end is terminated as a short. The signal amplitude of the fundamental component was calculated and compared with that of the second harmonic component. The designed BPM was fabricated and a low-power RF test was conducted. In this paper, the design, fabrication and low power test of the BPM for the PEFP linac are presented.

Oil companies push in-situ recovery

International Nuclear Information System (INIS)

McIntyre, H.

1977-01-01

Possibly, a third Athabaska tar-sand plant using surface mining will be built in the 1980's, but future development beyond that point will probably depend on in-situ recovery. The discussion of in-situ recovery focusses on the effect it will have on the Canadian chemical industry, for example, the market for sodium hydroxide. To obtain the highest yields of oil from bitumen, an external source of hydrogen is necessary; for example Syncrude imports natural gas to make hydrogen for desulphurization. Gasification of coal is a possible source of hydrogen. Research on hydrocracking is progressing. Use of a prototype CANDU OCR reactor to raise the hot steam necessary for in-situ recovery has been suggested. Venezuela is interested in Canadian upgrading technology. (N.D.H.)

rf conditioning and breakdown analysis of a traveling wave linac with collinear load cells

Science.gov (United States)

Chen, Qushan; Hu, Tongning; Qin, Bin; Xiong, Yongqian; Fan, Kuanjun; Pei, Yuanji

2018-04-01

Huazhong University of Science and Technology (HUST) has built a compact linac-based terahertz free electron laser (THz-FEL) prototype. In order to achieve compact structure, the linac uses collinear load cells instead of conventional output coupler to absorb remanent power at the end of linac. The new designed structure is confronted with rf breakdown problem after a long time conditioning process, so we tried to figure out the breakdown site in the linac. Without transmitted signal, we propose two methods to analyze the breakdown site mainly based on the forward and the reflected power signals. One method focuses on the time relationship of the two signals while the other focuses on the amplitude. Both the two methods indicate the breakdown events happened at the end of the linac and more likely in the first or the second load cell.

rf conditioning and breakdown analysis of a traveling wave linac with collinear load cells

Directory of Open Access Journals (Sweden)

Qushan Chen

2018-04-01

Full Text Available Huazhong University of Science and Technology (HUST has built a compact linac-based terahertz free electron laser (THz-FEL prototype. In order to achieve compact structure, the linac uses collinear load cells instead of conventional output coupler to absorb remanent power at the end of linac. The new designed structure is confronted with rf breakdown problem after a long time conditioning process, so we tried to figure out the breakdown site in the linac. Without transmitted signal, we propose two methods to analyze the breakdown site mainly based on the forward and the reflected power signals. One method focuses on the time relationship of the two signals while the other focuses on the amplitude. Both the two methods indicate the breakdown events happened at the end of the linac and more likely in the first or the second load cell.

The linac control system for the large-scale synchrotron radiation facility (SPring-8)

Energy Technology Data Exchange (ETDEWEB)

Sakaki, Hironao; Yoshikawa, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Itoh, Yuichi [Atomic Energy General Services Corporation, Tokai, Ibaraki (Japan); Terashima, Yasushi [Information Technology System Co., Ltd. (ITECS), Tokyo (Japan)

2000-09-01

The linac for large-scale synchrotron radiation facilities has been operated since August of 1996. The linac deal with the user requests without any big troubles. In this report, the control system development policy, details, and the operation for the linac are presented. It is also described so that these experiences can be used for control system of a large scale proton accelerators which will be developed in the High Intensity Proton Accelerator Project. (author)

Linac4 RFQ assembly is carried out before installation in Building 152

CERN Multimedia

Anna Pantelia

2012-01-01

This series of pictures documents the assembly phase of the Linac4 RFQ (Radio Frequency Quadrupole), performed at the end of July 2012. The Linac4 RFQ is made of 3 modules, 1 meter each, assembled together to accelerate the H- or proton beam from the ion source extraction at 45 kV to the energy of 3 MeV. The RFQ is the first of the Linac4 accelerating structures, which will increase to 160 MeV the beam injection energy into the PS Booster as from the end of LS2.

Linac Coherent Light Source (LCLS) Conceptual Design Report

Energy Technology Data Exchange (ETDEWEB)

Nuhn, Heinz-Dieter

2002-11-25

The Stanford Linear Accelerator Center, in collaboration with Argonne National Laboratory, Brookhaven National Laboratory, Los Alamos National Laboratory, Lawrence Livermore National Laboratory, and the University of California at Los Angeles, have collaborated to create a conceptual design for a Free-Electron-Laser (FEL) R&D facility operating in the wavelength range 1.5-15 {angstrom}. This FEL, called the ''Linac Coherent Light Source'' (LCLS), utilizes the SLAC linac and produces sub-picosecond pulses of short wavelength x-rays with very high peak brightness and full transverse coherence. The first two-thirds of the SLAC linac are used for injection into the PEP-II storage rings. The last one-third will be converted to a source of electrons for the LCLS. The electrons will be transported to the SLAC Final Focus Test Beam (FFTB) Facility, which will be extended to house a 122-m undulator system. In passing through the undulators, the electrons will be bunched by the force of their own synchrotron radiation to produce an intense, spatially coherent beam of x-rays, tunable in energy from 0.8 keV to 8 keV. The LCLS will include two experiment halls as well as x-ray optics and infrastructure necessary to make use of this x-ray beam for research in a variety of disciplines such as atomic physics, materials science, plasma physics and biosciences. This Conceptual Design Report, the authors believe, confirms the feasibility of constructing an x-ray FEL based on the SLAC linac.

Effect of cooling water on stability of NLC linac components

Energy Technology Data Exchange (ETDEWEB)

F. Le Pimpec et al.

2003-02-11

Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structures and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. A design, incorporating the proper decoupling of structure vibrations from the linac quadrupoles, is being pursued.

Effect of Cooling Water on Stability of NLC Linac Components

Energy Technology Data Exchange (ETDEWEB)

Le Pimpec, Frederic

2002-11-01

Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structures and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. A design, incorporating the proper decoupling of structure vibrations from the linac quadrupoles, is being pursued.

Induction linac driven relativistic klystron and cyclotron autoresonance maser experiments

International Nuclear Information System (INIS)

Goodman, D.L.; Birx, D.L.; Danly, B.G.

1991-01-01

In this paper design and experimental results are presented from two high power microwave generation experiments utilizing a high repetition rate induction linac generated electron beam. A relativistic klystron has generated more than 100 MW microwave pulses in X-band for 50 ns without pulse shortening or breakdown. design studies for the first cyclotron autoresonance maser (CARM) amplifier using an induction linac electron beam are also presented

Upgrade and development of nuclear data production test facility

Energy Technology Data Exchange (ETDEWEB)

Namkung, Won; Ko, I. S.; Cho, M. H.; Lee, Y. S.; Kang, H. S. [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of); Kim, G. N. [Kyungpook National Univ., Daegu (Korea, Republic of); Koh, S. K. [Univ. of Ulsan, Ulsan (Korea, Republic of); Ro, T. I. [Donga Univ., Busan (Korea, Republic of); Choi, G. U. [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

2005-04-15

It is necessary to improve the Pohang Neutron Facility (PNF) in order to be used as a nuclear data production facility for users in both domestic and abroad. We improved following items: upgrade the electron linac, collimators inside the TOF beam pipe, the development and installation of an automatic sample changer, the extension of the TOF beam line, and the data acquisition system. We would like to establish a utilization system for users to measure the nuclear data at the PNF. To do this, we made manuals for the accelerator operation and the data acquisition system. We also made an application form to apply for users to measure the nuclear data in both domestic and abroad. The main object of the Pohang Neutron Facility is to measure the nuclear data in the neutron energy region from thermal neutron to few hundreds of eV. In addition to neutron beams produced at the PNF, photon and electron beams are produced in this facility. We thus utilize this facility for other fields, such as test facility for detectors, activation experiments, polarized neutron beam source, and so on. In addition to these, we could use this facility for training students.

Sensitivity study of a proposed polarimetry diagnostic on ASDEX upgrade

International Nuclear Information System (INIS)

Callaghan, H.P.; McCarthy, P.J.

1994-09-01

ASDEX-Upgrade currently uses FIR interferometry (DCN, 195 μm) as a technique for measuring line integrated electron density along eight chords of the plasma cross-section. A polarimetry diagnostic based on Faraday rotation using the existing setup would yield ∫ n e B.dl along the same chords which, in combination with the ∫ n e dl measurements, would provide additional information about the poloidal magnetic field. This would be helpful for reconstructing the q(ψ) profile, which is difficult to recover from external magnetic measurements alone. A sensitivity study to determine the effectiveness of adding polarimetry to ASDEX Upgrade is carried out using function parameterization on a simulated equilibrium database, together with a database of randomly chosen density profiles with four degrees of freedom. The robustness of the recovery in the presence of measurement noise and the effects of plasma birefringence are taken into account. (orig.)

Low power rf system for the ALS Linac

International Nuclear Information System (INIS)

Lo, C.C.; Taylor, B.; Lancaster, H.

1991-05-01

The Linear Accelerator (Linac) in the Advanced Light Source (ALS) is designed to provide either single or multiple bunchers of 50 MeV electrons for the booster synchrotron. Three cavities are used in the Linac for electron bunching. The two subharmonic bunching cavities operate at 124.914 MHz and 499.654 MHz respectively. The S Band buncher operates at 2.997924 GHz. The low level RF system includes a master signal source, RF burst generators, signal phase control, timing trigger generators and a water temperature control system. The design and performance of the system will be described. 7 refs., 3 figs

Tranverse beam break up in a periodic linac

International Nuclear Information System (INIS)

Decker, G.; Wang, J.M.

1987-01-01

The problem of cumulative beam break up in a periodic linac for a general impedance is discussed, with the effects of acceleration included. The transverse equations of motion for a set of identical point like bunches moving along the length of the linac are cast into a simple form using a smooth approximation. This results in a working formula that is used to analyze beam breakup. Explicit expressions for the transverse motion in the case of a single resonance impedance are found using saddle point integration. This is done first with no external focusing, and again in the strong focusing limit

Overview and status of RF systems for the SSC Linac

International Nuclear Information System (INIS)

Mynk, J.; Grippe, J.; Cutler, R.I.; Rodriguez, R.

1993-05-01

The Superconducting Super Collider (SSC) Linear Accelerator (Linac) produces a 600-MeV, 35-μs, H-beam at a 10-Hz repetition rate. The beam is accelerated by a series of RF cavities. These consist of a Radio Frequency Quadrupole (RFQ), two bunchers, and four Drift Tube Linac (DTL) tanks at 427.617 MHz, and two bunchers, nine side-coupled Linac modules, and an energy compressor at 1282.851 MHz. The RFQ amplifier and the low-frequency buncher cavity amplifiers use gridded tubes, while the other cavities use klystron amplifier systems. The RF control system consists of a reference line and cavity feedback and feedforward loops for each amplifier. The RF amplifier system for each of these accelerator cavities is described, and the current status of each system is presented

Emittance growth in rf linacs

International Nuclear Information System (INIS)

Jameson, R.A.

1979-01-01

As the space-charge limit is approached, the current that can be accelerated in an rf linac and the output emittance that can be expected are discussed. The role of the envelope equations to estimate limits is outlined. The results of numerical experiments to explore general properties of emittance growth are given

Poster - 53: Improving inter-linac DMLC IMRT dose precision by fine tuning of MLC leaf calibration

International Nuclear Information System (INIS)

Nakonechny, Keith; Tran, Muoi; Sasaki, David; Beck, James; Poirier, Yannick; Malkoske, Kyle

2016-01-01

Purpose: To develop a method to improve the inter-linac precision of DMLC IMRT dosimetry. Methods: The distance between opposing MLC leaf banks (“gap size”) can be finely tuned on Varian linacs. The dosimetric effect due to small deviations from the nominal gap size (“gap error”) was studied by introducing known errors for several DMLC sliding gap sizes, and for clinical plans based on the TG119 test cases. The plans were delivered on a single Varian linac and the relationship between gap error and the corresponding change in dose was measured. The plans were also delivered on eight Varian 2100 series linacs (at two institutions) in order to quantify the inter-linac variation in dose before and after fine tuning the MLC calibration. Results: The measured dose differences for each field agreed well with the predictions of LoSasso et al. Using the default MLC calibration, the variation in the physical MLC gap size was determined to be less than 0.4 mm between all linacs studied. The dose difference between the linacs with the largest and smallest physical gap was up to 5.4% (spinal cord region of the head and neck TG119 test case). This difference was reduced to 2.5% after fine tuning the MLC gap calibration. Conclusions: The inter-linac dose precision for DMLC IMRT on Varian linacs can be improved using a simple modification of the MLC calibration procedure that involves fine adjustment of the nominal gap size.

Poster - 53: Improving inter-linac DMLC IMRT dose precision by fine tuning of MLC leaf calibration

Energy Technology Data Exchange (ETDEWEB)

Nakonechny, Keith; Tran, Muoi; Sasaki, David; Beck, James; Poirier, Yannick; Malkoske, Kyle [Simcoe-Muskoka Regional Cancer Centre (Canada)

2016-08-15

Purpose: To develop a method to improve the inter-linac precision of DMLC IMRT dosimetry. Methods: The distance between opposing MLC leaf banks (“gap size”) can be finely tuned on Varian linacs. The dosimetric effect due to small deviations from the nominal gap size (“gap error”) was studied by introducing known errors for several DMLC sliding gap sizes, and for clinical plans based on the TG119 test cases. The plans were delivered on a single Varian linac and the relationship between gap error and the corresponding change in dose was measured. The plans were also delivered on eight Varian 2100 series linacs (at two institutions) in order to quantify the inter-linac variation in dose before and after fine tuning the MLC calibration. Results: The measured dose differences for each field agreed well with the predictions of LoSasso et al. Using the default MLC calibration, the variation in the physical MLC gap size was determined to be less than 0.4 mm between all linacs studied. The dose difference between the linacs with the largest and smallest physical gap was up to 5.4% (spinal cord region of the head and neck TG119 test case). This difference was reduced to 2.5% after fine tuning the MLC gap calibration. Conclusions: The inter-linac dose precision for DMLC IMRT on Varian linacs can be improved using a simple modification of the MLC calibration procedure that involves fine adjustment of the nominal gap size.

Enzyme Enhanced Protein Recovery from Green Biomass Pulp

DEFF Research Database (Denmark)

Dotsenko, Gleb; Lange, Lene

2017-01-01

of local protein resources based on upgrade from e.g. green plant biomass. In present work we consider different strategies for protein recovery from white clover and ryegrass screw press pulps, using aqueous extraction, as well as carbohydrases and proteases enhanced extraction. Protein recovery...... in these studies was determined as a yield of solubilized protein with regard to the total protein in a screw press pulp. Aqueous extraction at pH 8.0 resulted in approx. 40 % protein recovery, while proteases application (Savinase 16.0L, Novozymes) enabled twice higher protein yield. Application of plant cell...... pulp proteolyzates, generated by Savinase 16.0L protease....

Relocatable cargo x-ray inspection systems utilizing compact linacs

International Nuclear Information System (INIS)

Sapp, W. Wade; Adams, William L.; Callerame, Joseph; Grodzins, Lee; Rothschild, Peter J.; Schueller, Richard; Mishin, Andrey V.; Smith, Gerald J.

2001-01-01

Magnetron-powered, X-band linacs with 3-4 MeV capability are compact enough to be readily utilized in relocatable high energy cargo inspection systems. Just such a system is currently under development at AS and E trade mark sign using the commercially available ISOSearch trade mark sign cargo inspection system as the base platform. The architecture permits the retention of backscatter imaging, which has proven to be an extremely valuable complement to the more usual transmission images. The linac and its associated segmented detector will provide an additional view with superior penetration and spatial resolution. The complete system, which is housed in two standard 40 ' ISO containers, is briefly described with emphasis on the installation and operating characteristics of the portable linac. The average rf power delivered by the magnetron to the accelerator section can be varied up to the maximum of about 1 kW. The projected system performance, including radiation dose to the environment, will be discussed and compared with other high energy systems

Heavy ion induction linac drivers for inertial confinement fusion

International Nuclear Information System (INIS)

Lee, E.P.; Hovingh, J.

1988-10-01

Intense beams of high energy heavy ions (e.g., 10 GeV Hg) are an attractive option for an ICF driver because of their favorable energy deposition characteristics. The accelerator systems to produce the beams at the required power level are a development from existing technologies of the induction linac, rf linac/storage ring, and synchrotron. The high repetition rate of the accelerator systems, and the high efficiency which can be realized at high current make this approach especially suitable for commercial ICF. The present report gives a summary of the main features of the induction linac driver system, which is the approach now pursued in the USA. The main subsystems, consisting of injector, multiple beam accelerator at low and high energy, transport and pulse compression lines, and final focus are described. Scale relations are given for the current limits and other features of these subsystems. 17 refs., 1 fig., 1 tab

Design and development of R.F. LINAC accelerator components