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in subjects: "Secondary Beams"

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Theory and measurement of the electron cloud effect.

Photoelectrons produced through the interaction of synchrotrons radiation and the vacuum chamber walls can be accelerated by a charged particle beam, acquiring sufficient energy to produce secondary electrons (SES) in collisions with the walls. If the secondary-electron yield (SEY) coefficient of the wall material is greater than one, a run-away condition can develop. In addition to the SEY, the degree of amplification depends on the beam intensity and temporal distribution. As the electron clo… more

Date: April 29, 1999

Creator: Harkey, K. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measurements of the electron cloud in the APS storage ring.

Synchrotron radiation interacting with the vacuum chamber walls in a storage ring produce photoelectrons that can be accelerated by the beam, acquiring sufficient energy to produce secondary electrons in collisions with the walls. If the secondary-electron yield (SEY) coefficient of the wall material is greater than one, as is the case with the aluminum chambers in the Advanced Photon Source (APS) storage ring, a runaway condition can develop. As the electron cloud builds up along a train of st… more

Date: April 16, 1999

Creator: Harkey, K. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An advanced ISOL facility based on ATLAS.

The Argonne concept for an accelerator complex for efficiently producing high-quality radioactive beams from ion source energy up to 6-15 MeV/u is described. The Isotope-Separator-On-Line (ISOL) method is used. A high-power driver accelerator produces radionuclides in a target that is closely coupled to an ion source and mass separator. By using a driver accelerator which can deliver a variety of beams and energies the radionuclide production mechanisms can be chosen to optimize yields for the … more

Date: February 24, 1999

Creator: Nolen, J. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Report to users of ATLAS - September 1998.

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 f… more

Date: November 18, 1998

Creator: Ahmad, I. & Hofman, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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

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.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

In-beam production and transport of radioactive {sup 17}F at ATLAS.

Beam currents of radioactive {sup 17}F(T{sub 1/2} = 65s) as high as 2 x 10{sup 6} s{sup {minus}1} have been produced at the ATLAS facility and delivered to target for nuclear physics research. The d({sup 16}O, {sup 17}F)n and p({sup 17}O,{sup 17}F)n reaction were used to produce the {sup 17}F in the energy range of 65-110 MeV with {sup 17}F intensities of up to 250 pnA. The target employed is a liquid nitrogen cooled H{sub 2} gas cell, with HAVAR windows, operating at up to 8 x 10{sup 4} Pa pre… more

Date: November 30, 1998

Creator: Pardo, R. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Accelerator development for a radioactive beam facility based on ATLAS.

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 … more

Date: January 8, 1998

Creator: Shepard, K. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Electronic sputtering and desorption effects in TOF-SIMS studies using slow highly charged ions like Au{sup 69+}

Secondary ion yields from highly oriented pyrolytic graphite (HOPG) and SiO{sub 2} (native oxide on float zone silicon) targets at impact of slow (v {approx} 0.3 v{sub bohr}) highly charged ions have been measured by Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS). A direct comparison of collisional and electronic effects in secondary ion production using a beam of charge state equilibrated 300 keV Xe{sup 1+} shows a secondary ion yield increase with incident ion charge of {>=}100.

Date: September 1, 1996

Creator: Schenkel, T.; Briere, M.A.; Schmidt-Boecking, H.; Bethge, K. & Schneider, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

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

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… more

Date: October 1, 1996

Creator: Harss, B.; Berger, J.C. & Greene, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Monte Carlo simulations of muon production

Muon production requirements for a muon collider are presented. Production of muons from pion decay is studied. Lithium lenses and solenoids are considered for focusing pions from a target, and for matching the pions into a decay channel. Pion decay channels of alternating quadrupoles and long solenoids are compared. Monte Carlo simulations are presented for production of {pi} {yields} {mu} by protons over a wide energy range, and criteria for choosing the best proton energy are discussed.

Date: March 1, 1995

Creator: Palmer, R. B.; Gallardo, J. C.; Fernow, R. C.; Torun, Y.; Neuffer, D. & Winn, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

KTeV beam systems design report

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.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High Intensity Performance and Upgrades at the Brookhaven AGS

Fig. 1 shows the present layout of the AGS-RHIC accelerator complex. The high intensity proton beam of the AGS is used both for the slow-extracted-beam (SEB) area with many target station to produce secondary beams and the fast-extracted-beam (FEB) line used for the production of muons for the g-2 experiment and for high intensity target testing for the spallation neutron sources and muon production targets for the muon collider. The same FEB line will also be used for the transfer of beam to R… more

Date: May 4, 1998

Creator: Roser, T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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

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… more

Date: July 17, 2001

Creator: Gai, W.; Conde, M. E.; Konecny, R.; Power, J. G.; Schoessow, P.; Simpson, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of Titanium Nitride Coating for Sns Ring Vacuum Chambers.

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.… more

Date: June 18, 2001

Creator: He, P.; Hseuh, H. C.; Mapes, M.; Todd, R. & Weiss, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Production of High Brightness Proton Bunches

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.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Report of the Snowmass M6 Working Group on High Intensity Proton Sources

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 (Hi… more

Date: August 14, 2001

Creator: Chou, W. & Wei, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Updated electron-cloud simulation results for the Large Hadron Collider (LHC)

This paper presents new simulation results for the power deposition from the electron cloud in the beam screen of the Large Hadron Collider (LHC). We pay particular attention to the sensitivity of the results to certain low-energy parameters of the secondary electron (SE)emission. Most of these parameters, which constitute an input to the simulation program, are extracted from recent measurements at CERN and SLAC.

Date: June 26, 2001

Creator: Furman, M. A. & Pivi, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Design and measurements of a deflecting mode cavity for an RF separator

The Fermilab Main Injector can produce intense 120 GeV/c proton beams for fixed target experimentation. Two deflecting mode RF systems can be used to separate charged kaons from a momentum selected secondary beam, consisting of pions, kaons and protons, using a time of flight method. We present the RF design of a 3.9 GHz superconducting cavity which operates in the deflecting (TM110) pi-mode and the dependence of the RF parameters on the cavity shape, as determined with finite difference calcul… more

Date: July 9, 2001

Creator: Bellantoni, Leo

Item Type: Article

Partner: UNT Libraries Government Documents Department

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

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, a… more

Date: December 5, 2002

Creator: al., N. Mokhov et

Item Type: Article

Partner: UNT Libraries Government Documents Department

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

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 techno… more

Date: August 20, 2002

Creator: Wei, Weiren Chou and J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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

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 alrea… more

Date: May 1, 1986

Creator: Arenton, M.; Chen, T. Y.; Lai, K. W.; Yao, N.; U., /Arizona; Anassontzis, S. E. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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

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 possibil… more

Date: March 1, 2012

Creator: Scarpine, Victor E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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BNL Multi-Particle Spectrometer (MPS) facility

No Description Available.

Date: May 1975

Creator: Lindenbaum, S. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Muon shielding calculations: heterogeneous passive and active shields, applications to experimental beams and areas

With the advent of a new generation of high-energy and high-intensity proton accelerators such as the one being built at the National Accelerator Laboratory and the one proposed by CERN, the problem of shielding external proton targets, the secondary beams produced from these targets, and even the secondary targets in the experimental areas becomes quite a massive and expensive project. In addition to the massive hadron shielding required, the high-energy muons produced by the decay of pions an… more

Date: January 1, 1971

Creator: Theriot, D.; Awschalom, M. & Lee, K.

Item Type: Article

Partner: UNT Libraries Government Documents Department