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Experimental demonstration of two beam acceleration using dielectric step-up transformer.

Description: We report on the experimental results of the dielectric based two beam accelerator (step-up transformer). By using a single high charge beam, we have generated and extracted a high power RF pulse from a 7.8 GHz primary dielectric structure and then subsequently transferred to a second accelerating structure with higher dielectric constant and smaller transverse dimensions. We have measured the energy change of a second (witness) beam passing through the acceleration stage. The measured gradient is > 4 times the deceleration gradient. The detailed experiment of set-up and results of the measurements are discussed. Future plans for the development of a 100 MeV demonstration accelerator based on this technique is presented.
Date: July 17, 2001
Creator: Gai, W.; Conde, M.E.; Konecny, R.; Power, J.G.; Schoessow, P.; Simpson, J. et al.
Partner: UNT Libraries Government Documents Department


Description: The M6 working group had more than 40 active participants (listed in Section 4). During the three weeks at Snowmass, there were about 50 presentations, covering a wide range of topics associated with high intensity proton sources. The talks are listed in Section 5. This group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), E5 (Fixed-Target Experiments), M1 (Muon Based Systems), T4 (Particle Sources), T5 (Beam dynamics), T7 (High Performance Computing) and T9 (Diagnostics). The M6 group performed a survey of the beam parameters of existing and proposed high intensity proton sources, in particular, of the proton drivers. The results are listed in Table 1. These parameters are compared with the requirements of high-energy physics users of secondary beams in Working Groups E1 and E5. According to the consensus reached in the E1 and E5 groups, the U.S. HEP program requires an intense proton source, a 1-4 MW Proton Driver, by the end of this decade.
Date: August 14, 2001
Creator: CHOU,W. & WEI,J.
Partner: UNT Libraries Government Documents Department

Performance of the KTeV high-energy neutral kaon beam at Fermilab

Description: The performance of the primary and secondary beams for the KTeV experiments E832 and E799-II is reviewed. The beam was commissioned in the summer of 1996 and initially operated for approximately one year. The report includes results on the primary beam, target station including primary beam dump and muon sweeping system, neutral beam collimation system, and alignment.
Date: June 1, 1998
Creator: Bocean, V.
Partner: UNT Libraries Government Documents Department

P-West High Intensity Secondary Beam Area Design Report

Description: This report gives the initial design parameters of a 1000 GeV High Intensity Superconducting Secondary Beam Laboratory to be situated in the Proton Area downstream of the existing Proton West experimental station. The area will provide Fermilab with a major capability for experimentation with pion and antiproton beams of intensities and of energies available at no other laboratory and with an electron beam with excellent spot size, intensity, and purity at energies far above that available at electron machines. Detailed beam design, area layouts, and cost estimates are presented, along with the design considerations.
Date: March 1, 1977
Creator: Cox, A.; Currier, R.; Eartly, D.; Guthke, A.; Johnson, G.; Lee, D. et al.
Partner: UNT Libraries Government Documents Department


Description: Rapid cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: (a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics (b) long straight sections for low-loss injection, extraction, and high-efficiency collimation (c) dispersion-free straights to avoid longitudinal-transverse coupling, and (d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.
Date: June 23, 2006
Creator: WANG, S.; WEI, J.; BROWN, K.; GARDNER, C.; LEE, Y.Y.; LOWENSTEIN, D. et al.
Partner: UNT Libraries Government Documents Department

Transverse beam shape measurements of intense proton beams using optical transition radiation

Description: A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.
Date: March 1, 2012
Creator: Scarpine, Victor E.
Partner: UNT Libraries Government Documents Department

Report of the Snowmass T4 working group on particle sources: Positron sources, anti-proton sources and secondary beams

Description: This report documents the activities of the Snowmass 2001 T4 Particle Sources Working Group. T4 was charged with examining the most challenging aspects of positron sources for linear colliders and antiproton sources for proton-antiproton colliders, and the secondary beams of interest to the physics community that will be available from the next generation of high-energy particle accelerators. The leading issues, limiting technologies, and most important R and D efforts of positron production, antiproton production, and secondary beams are discussed in this paper. A listing of T4 Presentations is included.
Date: December 5, 2002
Creator: al., N. Mokhov et
Partner: UNT Libraries Government Documents Department


Description: Strongly pulsed proton beams for secondary beam production are required for projects such as pulsed spallation neutron sources or neutrino factories where accurate time-of-flight information is required. To meet these demands techniques to produce multi-GeV proton bunches with very high longitudinal brightness are being developed. A review of the present status is presented.
Date: June 18, 2001
Creator: ROSER,T.
Partner: UNT Libraries Government Documents Department

Report to users of ATLAS - September 1998.

Description: The ATLAS facility has provided a total of 5749 hours of beam for research in FY1998. The accelerator operation had a very high 93% reliability factor during that period. With the startup of Gammasphere in January, our schedule has attempted to minimize scheduled downtime and maximize beam-time for research. Our best performance so far occurred during the month of May when a total of 639 hours was provided for research. From the accelerator point-of-view, recent major highlights have included first operation of a new production configuration for our {sup 17}F beams which increased the beam current on-target to 2 x 10{sup 6} {sup 17}F ions/see. The {sup 17}F production target was moved approximately 4 meters upstream and a new superconducting solenoid was added to the system to refocus the highly divergent secondary beam. This new location also places the target upstream of a new superconducting resonator which was used to reduce the energy spread of the beam delivered to the spectrograph to less than 300 keV (FWHM). An improved, liquid nitrogen cooled, multiple gas cell has also significantly contributed to better performance.
Date: November 18, 1998
Creator: Ahmad, I. & Hofman, D.
Partner: UNT Libraries Government Documents Department

Accelerator development for a radioactive beam facility based on ATLAS.

Description: The existing superconducting linac ATLAS is in many respects an ideal secondary beam accelerator for an ISOL (Isotope separator on-line) type radioactive beam facility. Such a facility would require the addition of two major accelerator elements: a low charge state injector for the existing heavy ion linac, and a primary beam accelerator providing 220 MV of acceleration for protons and light ions. Development work for both of these elements, including the option of superconducting cavities for the primary beam accelerator is discussed.
Date: January 8, 1998
Creator: Shepard, K. W.
Partner: UNT Libraries Government Documents Department

The MERIT High-Power Target Experiment at the CERN PS.

Description: The MERIT experiment was designed as a proof-of-principle test of a target system based on a free mercury jet inside a 15-T solenoid that is capable of sustaining proton beam powers of up to 4 MW. The experiment was run at CERN in the fall of 2007. We describe the results of the tests and their implications. Plans are being discussed for possible future machines which can deliver proton beams with multi-MW beam powers. A prominent application for these powerful beams will be to produce intense secondary beams suitable for investigating important physics issues. Examples include investigations of rare decay processes and neutrino oscillations. The Neutrino Factory and Muon Collider Collaboration [1] has proposed a target system [2, 3] which will be capable of supporting proton beam powers of 4 MW with the purpose of producing and collecting intense muon beams for eventual use in storage rings. The core of this proposed target system consists of a high-Z, free-flowing liquid mercury jet which intercepts the proton beam within the confines of a high-field (15-20 T) solenoid. An important attribute of this system is that the liquid jet target can be replaced for subsequent proton pulses. The experiment described in this paper was designed to provide a proof-of-principle demonstration of this concept. Preparations for this experiment have been previously reported [4].
Date: June 23, 2008
Creator: Kirk,H.G.; Tsang, T.; Efthymiopoulos, I.; Fabich, A.; Haug, F.; Lettry, J. et al.
Partner: UNT Libraries Government Documents Department

Evolutionary algorithm for the neutrino factory front end design

Description: The Neutrino Factory is an important tool in the long-term neutrino physics program. Substantial effort is put internationally into designing this facility in order to achieve desired performance within the allotted budget. This accelerator is a secondary beam machine: neutrinos are produced by means of the decay of muons. Muons, in turn, are produced by the decay of pions, produced by hitting the target by a beam of accelerated protons suitable for acceleration. Due to the physics of this process, extra conditioning of the pion beam coming from the target is needed in order to effectively perform subsequent acceleration. The subsystem of the Neutrino Factory that performs this conditioning is called Front End, its main performance characteristic is the number of the produced muons.
Date: January 1, 2009
Creator: Poklonskiy, Alexey A.; U., /Michigan State; Neuffer, David & /Fermilab
Partner: UNT Libraries Government Documents Department

A Proposal to Study Beauty Production and Other Heavy Quark Physics Associated with Dimuon Production in 800 (925) GeV/C pp Interactions

Description: The presence of dimuons in final states produced in hadronic interactions has proved to be a valuable indicator that interesting hard physics processes have taken place. These muon pairs provide a mechanism for selecting these relatively rare processes from interactions due to the total cross section. In particular, processes involving heavy quarks are flagged by the presence of muon pairs. We are proposing to use the high rate E705 spectrometer and its dimuon trigger processor which have already functioned well in Experiments E-537 and E-705 to detect and measure several heavy quark phenomena which result in a final state containing a pair of muons. This experiment will use the primary proton beam from the Tevatron at the maximum energy available at the time of execution of the experiment. The spectrometer will be augmented by the addition of a silicon tracker similar to those used in other experiments at the Fermilab. The present P-West High Intensity Laboratory secondary beams will need to be upgraded by addition of sufficient bending power to allow the transport of the 800 to 925 GeV/c primary proton beam to the experiment target (see Appendix A).
Date: May 1, 1986
Creator: Arenton, M.; Chen, T.Y.; Lai, K.W.; Yao, N.; U., /Arizona; Anassontzis, S.E. et al.
Partner: UNT Libraries Government Documents Department

A proposal to study particle production spectra and multiplicities in high energy hadron-hadron collisions, and for a beam survey and quark search

Description: We propose an experimental study at the new 500 GeV accelerator of the differential cross-section for particle production in hadron-hadron collisions. The projectile, and the observed single particle, will range over all combinations of positive and negative {pi}, K and p, with momenta extending up to the highest available. Enough of the secondary particle momentum range will be covered to permit us to determine by integration the multiplicity of the produced particle. Single particles will be detected in a simple spectrometer consisting of wire chambers and a small bending magnet. The configuration of the spectrometer components will be variable so that the overall spectrometer length can be kept proportional to the secondary momentum. The momentum resolution {male}P/P = {+-}0.8% and the invariant phase space acceptance P{sup 2}d{Omega}dP/E = 1.3x10{sup -3} (GeV/c){sup 2} will then be the same at all momenta. Particle identification will be by means of threshold Cherenkov counters, with 10{sup 4}: 1 rejection up to at least 250 GeV/c. Our experimental arrangement is thought to be simple and yet powerful, and we propose its use initially with incident protons and a nuclear target for a beam survey and quark search. Subsequent measurements will be carried out with a hydrogen target in a high intensity secondary beam.
Date: June 15, 1970
Creator: Beier, E.W.; Kreinick, D.L.; Weisberg, H. & U., /Pennsylvania
Partner: UNT Libraries Government Documents Department

Secondary beam monitors for the NuMI facility at FNAL

Description: The Neutrinos at the Main Injector (NuMI) facility is a conventional neutrino beam which produces muon neutrinos by focusing a beam of mesons into a long evacuated decay volume. We have built four arrays of ionization chambers to monitor the position and intensity of the hadron and muon beams associated with neutrino production at locations downstream of the decay volume. This article describes the chambers construction, calibration, and commissioning in the beam.
Date: July 1, 2006
Creator: Kopp, S.; Bishai, M.; Dierckxsens, M.; Diwan, M.; Erwin, A. R.; Harris, D. A. et al.
Partner: UNT Libraries Government Documents Department

Estimate of particle fluxes from the IR's at the SSC

Description: There exists a considerable amount of interest in exploring the possibility of doing secondary beam physics at SSC. There are at least three obvious ways of obtaining secondary beams at the SSC, namely: (a) extraction of the primary stored beam and its subsequent targeting to generate secondary beams; (b) generation of secondary beams from internal target, either gas jet or thin wire or foil; and (c) utilization of particles produced in the primary collisions in the interaction regions. This note summarizes some calculations performed on the yields generated via the third mechanism. 2 references, 3 figures.
Date: November 1, 1984
Creator: Hwa, T. & Wojcicki, S.G.
Partner: UNT Libraries Government Documents Department

The first production and transport of radioactive {sup 17}F at ATLAS for research

Description: A secondary beam of radioactive {sup 17}F was produced at the ATLAS accelerator and delivered to an experimental target station with an intensity of at least 2 x 10{sup 5} particles per second for use in the research program. The beam was produced through the p({sup 17}O, {sup 17}F)n inverse reaction by bombarding a hydrogen gas target with 250 particle nA of 83 MeV {sup 17}O from the ATLAS superconducting linac. The gas target was maintained at a pressure of 300 Torr and a temperature of 257 K. Beam quality was dominated by multiple scattering in the gas cell windows and by the reaction kinematics and beamline acceptance for energy spread.
Date: October 1, 1996
Creator: Harss, B.; Berger, J.C. & Greene, J.
Partner: UNT Libraries Government Documents Department

Report of the Snowmass M6 Working Group on high intensity proton sources

Description: The U.S. high-energy physics program needs an intense proton source, a 1-4 MW Proton Driver (PD), by the end of this decade. This machine will serve as a stand-alone facility that will provide neutrino superbeams and other high intensity secondary beams such as kaons, muons, neutrons, and anti-protons (cf. E1 and E5 group reports) and also serve as the first stage of a neutrino factory (cf. M1 group report). It can also be a high brightness source for a VLHC. Based on present accelerator technology and project construction experience, it is both feasible and cost-effective to construct a 1-4 MW Proton Driver. Two recent PD design studies have been made, one at FNAL and the other at the BNL. Both designed PD's for 1 MW proton beams at a cost of about U.S. $200M (excluding contingency and overhead) and both designs were upgradeable to 4 MW. An international collaboration between FNAL, BNL and KEK on high intensity proton facilities is addressing a number of key design issues. The superconducting (sc) RF cavities, cryogenics, and RF controls developed for the SNS can be directly adopted to save R&D efforts, cost, and schedule. PD studies are also actively being pursued at Europe and Japan.
Date: August 20, 2002
Creator: Wei, Weiren Chou and J.
Partner: UNT Libraries Government Documents Department

KTeV beam systems design report

Description: The primary and secondary beams for the KTeV experiments E799-II and E832 are discussed. The specifications are presented and justified. The technical details of the implementation of the primary beam transport and stability are detailed. The target, beam dump, and radiation safety issues are discussed. The details of the collimation system for the pair of secondary beams are presented.
Date: September 1, 1997
Creator: Bocean, V.; Childress, S. & Coleman, R.
Partner: UNT Libraries Government Documents Department


Description: The inner surface of the ring vacuum chambers of the US Spallation Neutron Source (SNS) will be coated with {approximately}100 nm of Titanium Nitride (TiN). This is to minimize the secondary electron yield (SEY) from the chamber wall, and thus avoid the so-called e-p instability caused by electron multipacting as observed in a few high-intensity proton storage rings. Both DC sputtering and DC-magnetron sputtering were conducted in a test chamber of relevant geometry to SNS ring vacuum chambers. Auger Electron Spectroscopy (AES) and Rutherford Back Scattering (RBS) were used to analyze the coatings for thickness, stoichiometry and impurity. Excellent results were obtained with magnetron sputtering. The development of the parameters for the coating process and the surface analysis results are presented.
Date: June 18, 2001
Creator: HE,P.; HSEUH,H.C.; MAPES,M.; TODD,R. & WEISS,D.
Partner: UNT Libraries Government Documents Department