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Calculation of integrated luminosity for beams stored in the Tevatron collider

Description: A model for calculating the integrated luminosity of beams stored in the Tevatron collider will be presented. The model determines the instantaneous luminosity by calculating the overlap integral of bunched beams passing through the interaction region. The calculation accounts for the variation in beam size due to the beta functions and also for effects due to finite longitudinal emittance and non-zero dispersion in the interaction region. The integrated luminosity is calculated for the beams as they evolve due to processes including collisions and intrabeam scattering. The model has been applied to both the extant and upgraded Tevatron collider, but is not limited to them. The original motivation for developing the computer model was to determine the reduction in luminosity due to beams with non-zero longitudinal emittances. There are two effects: the transverse beam size is increased where the dispersion is non-zero; the finite length of the beam bunch combined with an increasing /beta/ function results in an increased transverse beam size at the ends of the bunch. The derivation of a sufficiently useful analytic expression for the luminosity proved to be intractable. Instead, a numerical integration computer program was developed to calculate the luminosity in the presence of a finite longitudinal emittance. The program was then expanded into a model which allows the luminosity to vary due to changes in emittances and reduction in bunch intensities. At that point, it was not difficult to calculate the integrated luminosity. 5 refs., 2 figs., 4 tabs.
Date: March 20, 1989
Creator: Finley, D.A.
Partner: UNT Libraries Government Documents Department

Fermilab Collider: Performance and plans

Description: The Fermilab collider program has completed its first physics run with two major detectors, CDF and DO. Recent performance of the Fermilab accelerator complex during Run Ia is presented, along with plans to improve the luminosity of the collider. The beam-beam tune shift limitations of previous runs have been avoided by the successful implementation of electrostatic separators in the Tevatron. The simultaneous operation of two high luminosity sections is provided by two matched low beta inserts. The Antiproton Source has increased its performance over the previous run as measured by stack size and stacking rate. The Linac will be upgraded from 200 MeV to 400 MeV in order to lessen the space charge tune shift upon injection into the Booster and provide proton beams with increased intensity with the same emittance. Higher luminosity requires more bunches in the Tevatron to again avoid the limitation due to the beam-beam interaction. Until it is replaced with the Main Injector, the Main Ring will remain as the most significant bottleneck on the performance of the collider.
Date: December 1, 1993
Creator: Finley, D. A.
Partner: UNT Libraries Government Documents Department

Turning inspection regulations into training tools

Description: In response to suggestions from internal and State of California auditors, the Hazardous Waste Management Division (HWM) at Lawrence Livermore National Laboratory prepared an Inspection Schedule and Guidance Document that summarizes the Laboratory`s inspection schedule and procedures for waste treatment, storage, and disposal facilities (TSDFs). Because it explains and comments in detail on the inspection schedule, forms, and procedures, this document is a centralized reference for HWM managers and personnel performing TSDF inspections at the Laboratory. It is also a training tool for experienced and new inspectors, standardizing the inspections of personnel with experience and explaining to novices what to look for and why. This poster presentation traces the team effort that created this document and provides specific examples of how the document was developed and how it is used.
Date: January 1, 1996
Creator: Finley, D. & Wheatcraft, D.
Partner: UNT Libraries Government Documents Department

Tevatron extraction microcomputer

Description: Extraction in the Fermilab Tevatron is controlled by a multi-processor Multibus microcomputer system called QXR (Quad eXtraction Regulator). QXR monitors several analog beam signals and controls three sets of power supplies: the ''bucker'' and ''pulse'' magnets at a rate of 5760 Hz, and the ''QXR'' magnets at 720 Hz. QXR supports multiple slow spills (up to a total of 35 seconds) with multiple fast pulses intermixed. It linearizes the slow spill and bucks out the high frequency components. Fast extraction is done by outputting a variable pulse waveform. Closed loop learning techniques are used to improve performance from cycle to cycle for both slow and fast extraction. The system is connected to the Tevatron clock system so that it can track the machine cycle. QXR is also connected to the rest of the Fermilab control system, ACNET. Through ACNET, human operators and central computers can monitor and control extraction through communications with QXR. The controls hardware and software both employ some standard and some specialized components. This paper gives an overview of QXR as a control system; another paper summarizes performance.
Date: June 1, 1985
Creator: Chapman, L.; Finley, D.A.; Harrison, M. & Merz, W.
Partner: UNT Libraries Government Documents Department

Control and initial operation of the Fermilab BO low. beta. insertion

Description: The operation of the Fermilab BO low ..beta.. insertion involves the coordinated control of the 4 strings of quadrupoles of the insertion itself along with several magnetic correction elements (20 dipoles for the closed orbit, 2 quad circuits for betatron tunes, 1 skew quad circuit for coupling, and 2 sextupole circuits for chromaticity). When the beam is stored at high energy, these elements must correct the errors induced by the strong superconducting quadrupoles of the insertion as the optics are smoothly changed from the fixed target configuration to the low ..beta.. state. The techniques and control programs for these manipulations and initial tests using a single coasting beam are described. 6 refs., 4 figs.
Date: June 1, 1985
Creator: Finley, D.A.; Johnson, R.P. & Willeke, F.
Partner: UNT Libraries Government Documents Department

An energy upgrade from TESLA to a high-energy {mu}{sup +}{mu}{sup {minus}} collider

Description: We discuss the possible extension of a TESLA 250X250 GeV SRF e{sup +}e{sup -} linear collider to a multi-TeV {mu}{sup +}{mu}{sup -} collider, by future addition of a muon source, return arcs for recirculation and a collider ring. The TESLA SRF systems are potentially also suitable for multiturn acceleration of muon bunches, and could be adapted for use in a recirculating {mu}-linac. Many problems and design issues would need to be resolved, and further study is needed.
Date: October 1, 1996
Creator: Neuffer, D.; Edwards, H. & Finley, D.
Partner: UNT Libraries Government Documents Department

Tevatron status and future plans

Description: The performance of the Fermilab accelerator complex, which has led to the recent discovery of the top quark, is described. The status of the Tevatron at the end of the 4 year collider run and at the beginning of the fixed target run and of the Main Injector project is presented. It is expected that the Main Injector and other improvements in the complex will increase the luminosity up to 2 x 10{sup 12} cm{sup -2} s{sup -1} and will provide a high intensity 120 GeV proton beam to allow for a search for neutrino oscillations. Activities under consideration beyond the next collider run are discussed which can lead to a peak luminosity of 10{sup 33} cm{sup -2} s{sup -1}.
Date: November 1, 1996
Creator: Finley, D.A.; Marriner, J. & Mokhov, N.V.
Partner: UNT Libraries Government Documents Department

Compatibility of lead-free solders with lead containing surface finishes as a reliability issue in electronic assemblies

Description: Enhanced performance goals and environmental restrictions have heightened the consideration for use of alternative solders as replacements for the traditional tin-lead (Sn-Pb) eutectic and near-eutectic alloys. However, the implementation of non-Pb bearing surface finishes may lag behind solder alloy development. A study was performed which examined the effect(s) of Pb contamination on the performance of Sn-Ag-Bi and Sn-Ag-Cu-Sb lead-free solders by the controlled addition of 63Sn-37Pb solder at levels of 0.5 {minus} 8.0 wt.%. Thermal analysis and ring-in-plug shear strength studies were conducted on bulk solder properties. Circuit board prototype studies centered on the performance of 20I/O SOIC gull wing joints. Both alloys exhibited declines in their melting temperatures with greater Sn-Pb additions. The ring-in-plug shear strength of the Sn-Ag-Cu-Sb solder increased slightly with Sn-Pb levels while the Sn-Ag-Bi alloy experienced a strength loss. The mechanical behavior of the SOIC (Small Outline Integrated Circuit) Sn-Ag-Bi solder joints reproduced the strength levels were insensitive to 10,106 thermal cycles. The Sn-Ag-Cu-Sb solder showed a slight decrease in the gull wing joint strengths that was sensitive to the Pb content of the surface finish.
Date: March 1996
Creator: Vianco, P.; Rejent, J.; Artaki, I.; Ray, U.; Finley, D. & Jackson, A.
Partner: UNT Libraries Government Documents Department

Flying wires at Fermilab

Description: Transverse beam profile measurement systems called ''Flying Wires'' have been installed and made operational in the Fermilab Main Ring and Tevatron accelerators. These devices are used routinely to measure the emittance of both protons and antiprotons throughout the fill process, and for emittance growth measurements during stores. In the Tevatron, the individual transverse profiles of six proton and six antiproton bunches are obtained simultaneously, with a single pass of the wire through the beam. Essential features of the hardware, software, and system operation are explained in the rest of the paper. 3 refs., 4 figs.
Date: March 1, 1989
Creator: Gannon, J.; Crawford, C.; Finley, D.; Flora, R.; Groves, T. & MacPherson, M.
Partner: UNT Libraries Government Documents Department

Multibunch operation in the Tevatron Collider

Description: The Tevatron Collider at Fermilab is the world`s highest energy hadron collider, colliding protons with antiprotons at a center of mass energy of 1800 GeV. At present six proton bunches collide with six antiproton bunches to generate luminosities of up to 9 {times} 10{sup 30} cm{sup {minus}2}s{sup {minus}1}. It is estimated that to reach luminosities significantly greater than 10{sup 31} cm{sup {minus}2}s{sup {minus}1} while minimizing the number of interactions per crossing, the number of bunches will have to be increased. Thirty-six bunch operation looks like the most promising plan. This paper looks at the strategies for increasing the number of particle bunches, the new hardware that needs to be designed and changes to the operating mode in filling the Tevatron. An interactive program which simulates the filling of the Tevatron collider is also presented. The time scale for multibunch operation and progress towards running greater than six bunches is given in this paper.
Date: May 1, 1993
Creator: Holt, J. A.; Finley, D. A. & Bharadwaj, V.
Partner: UNT Libraries Government Documents Department

Work at FNAL to achieve long electron drift lifetime in liquid argon

Description: This note records some of the work done between July 2005 and July 2006 to achieve long (many milliseconds) electron drift lifetimes in liquid argon at Fermilab. The work is part of a process to develop some experience at Fermilab with the technology required to construct a large liquid argon TPC. This technology has been largely developed by the ICARUS collaboration in Europe and this process can be seen as technology transfer. The capability to produce liquid argon in which electrons have drift lifetimes of several milliseconds is crucial to a successful device. Liquid argon calorimeters have been successfully operated at Fermilab; their electro-negative contaminants are at the level of 10{sup -7} while the TPC we are considering requires a contamination level at the level of 10{sup -11}, tens of parts per trillion (ppt). As well as demonstrating the ability to produce liquid argon at this level of purity, the work is part of a program to test the effect on the electron drift time of candidate materials for the construction of a TPC in liquid argon.
Date: October 1, 2006
Creator: Finley, D.; Jaskierny, W.; Kendziora, C.; Krider, J.; Pordes, S.; Rapidis, P.A. et al.
Partner: UNT Libraries Government Documents Department

Wave soldering with Pb-free solders

Description: The manufacturing feasibility and attachment reliability of a series of newly developed lead-free solders were investigated for wave soldering applications. Some of the key assembly aspects addressed included: wettability as a function of board surface finish, flux activation and surface tension of the molten solder, solder joint fillet quality and optimization of soldering thermal profiles. Generally, all new solder formulations exhibited adequate wave soldering performance and can be considered as possible alternatives to eutectic SnPb for wave soldering applications. Further process optimization and flux development is necessary to achieve the defect levels associated with the conventional SnPb process.
Date: July 1, 1995
Creator: Artaki, I.; Finley, D.W.; Jackson, A.M.; Ray, U. & Vianco, P.T.
Partner: UNT Libraries Government Documents Department

Assessment of NiPd finished components for surface mount assembly applications

Description: Recent trends towards finer pitch devices and assembly with lead free solders have resulted in increased interest in NiPd plated component leads by the electronics industry. This paper discusses the performance of NiPd fine pitch components as determined by wettability, assembly performance and solder joint reliability. Assembly evaluations were performed with a lead free solder as well as with eutectic SnPb solder. The compatibility of the NiPd component leads with different circuit board finishes (metallic and organic azole) will also be discussed.
Date: August 1, 1995
Creator: Finley, D.W.; Ray, U.; Artaki, I.; Vianco, P.; Shah, S.; Reyes, A. et al.
Partner: UNT Libraries Government Documents Department

Prospects for tunes near the integer at the Fermilab PBAR-P Collider

Description: A series of experiments with the Tevatron collider has been made which has a goal the operation of the machine with betatron tunes near 19.05. Experiments near the integer working point are described, including closed orbit control, and emittance growth due to power supply noise. Results from a pbar-p store with large pbar tunes shifts and tunes near the integer are described. 4 refs., 3 figs.
Date: May 1, 1991
Creator: Siergiej, D.; Ankenbrandt, C.; Finley, D.; Goderre, G.; Johnson, R.P. & Zhang, P.
Partner: UNT Libraries Government Documents Department

Revised Proposal to Search for Heavy Resonances

Description: During October 1974, we submitted a most timely proposal to search for narrow, heavy resonances by measuring the effective mass spectrum of {pi}{pi}, {pi}K, KK, {pi}p, Kp and {bar p}p pairs. The subsequent discovery of a heavy, narrow resonance at SLAC and BNL caused much excitement and raised many new questions. In part, this may have been the reason why our proposal (No. 357) did not receive the consideration we feel it strongly deserved. We therefore resubmit our proposal, with additional clarification and improvement, and hope that the Program Advisory Committee and the Director will act favorably on our request to make these measurements.
Date: December 1, 1974
Creator: Jovanovic, D.; Lundy, R.; /Fermilab; Finley, D.; Loeffler, F.; Shibata, E. et al.
Partner: UNT Libraries Government Documents Department

Automated Microwave Low Power Testing Techniques for NLC

Description: As part of the Next Linear Collider (NLC) collaboration, the NLC structures group at Fermilab has started an R&D program to fabricate NLC accelerator structures in cooperation with commercial companies in order to prepare for mass production of RF structures. To build the Next Linear Collider, thousands accelerator structures containing a million cells are needed. Our primary goal is to explore the feasibility of making these structures in an industrial environment. On the other hand the structure mass production requires ''industrialized''microwave quality control techniques to characterize these structures at different stages of production as efficiently as possible. We developed several automated set-ups based on different RF techniques that are mutually complementary address this problem.
Date: July 8, 2005
Creator: Carter, H.; Finley, D.; Gonin, I.; Khabibullin, T.; Romanov, G.; Sun, D. et al.
Partner: UNT Libraries Government Documents Department

Muon Collider Task Force Report

Description: Muon Colliders offer a possible long term path to lepton-lepton collisions at center-of-mass energies {radical}s {ge} 1 TeV. In October 2006 the Muon Collider Task Force (MCTF) proposed a program of advanced accelerator R&D aimed at developing the Muon Collider concept. The proposed R&D program was motivated by progress on Muon Collider design in general, and in particular, by new ideas that have emerged on muon cooling channel design. The scope of the proposed MCTF R&D program includes muon collider design studies, helical cooling channel design and simulation, high temperature superconducting solenoid studies, an experimental program using beams to test cooling channel RF cavities and a 6D cooling demonstration channel. The first year of MCTF activities are summarized in this report together with a brief description of the anticipated FY08 R&D activities. In its first year the MCTF has made progress on (1) Muon Collider ring studies, (2) 6D cooling channel design and simulation studies with an emphasis on the HCC scheme, (3) beam preparations for the first HPRF cavity beam test, (4) preparations for an HCC four-coil test, (5) further development of the MANX experiment ideas and studies of the muon beam possibilities at Fermilab, (6) studies of how to integrate RF into an HCC in preparation for a component development program, and (7) HTS conductor and magnet studies to prepare for an evaluation of the prospects for of an HTS high-field solenoid build for a muon cooling channel.
Date: December 1, 2007
Creator: Ankenbrandt, C.; Alexahin, Y.; Balbekov, V.; Barzi, E.; Bhat, C.; Broemmelsiek, D. et al.
Partner: UNT Libraries Government Documents Department

Assessment of circuit board surface finishes for electronic assembly with lead-free solders

Description: The suitability of various metallic printed wiring board surface finishes was assessed for new technology applications that incorporate assembly with Lead-free solders. The manufacture of a lead-free product necessitates elimination of lead (Pb) from the solder, the circuit board as well as the component lead termination. It is critical however for the selected interconnect Pb-free solder and the corresponding printed wiring board (PWB) and component lead finishes to be mutually compatible. Baseline compatibility of select Pb-free solders with Pb containing PWB surface finish and components was assessed. This was followed by examining the compatibility of the commercially available CASTIN{trademark} (SnAgCuSb) Pb-free solder with a series of PWB metallic finishes: Ni/Au, Ni/Pd, and Pd/Cu. The compatibility was assessed with respect to assembly performance, solder joint integrity and long term attachment reliability. Solder joint integrity and mechanical behavior of representative 50 mil pitch 20I/O SOICs was determined before and after thermal stress. Mechanical pull test studies demonstrated that the strength of SnAgCuSb solder interconnections is notably greater than that of SnPb interconnections.
Date: October 1, 1996
Creator: Ray, U.; Artaki, I.; Finley, D. W.; Wenger, G. M.; Pan, T.; Blair, H. D. et al.
Partner: UNT Libraries Government Documents Department

Nonlinear dynamics experiment in the Tevatron

Description: Results of the continuing analysis of the nonlinear dynamics experiment E778 are presented. Sixteen special sextupoles introduced nonlinearities in the Tevatron. 'Smear,' which is one of the parameters used to quantify the degree of nonlinearity, was extracted from the data and compared with calculation. Injection efficiency in the presence of nonlinearities was studied. Measurements of the dynamic aperture were performed. The final results in one degree of freedom of the smear, the injection efficiency and the dynamic aperture are presented. Particles captured on nonlinear resonance islands were directly observed and measurements were performed. The capture efficiency was extracted from the data and compared with prediction. The influence of tune modulation on the stability of these islands was investigated. Plans for future measurements are discussed. 4 refs., 6 figs.
Date: January 1, 1989
Creator: Merminga, N.; Edwards, D.; Finley, D.; Gerig, R.; Gelfand, N.; Harrison, M. et al.
Partner: UNT Libraries Government Documents Department

1987 DOE review: First collider run operation

Description: This review covers the operations of the first run of the 1.8 TeV superconducting super collider. The papers enclosed cover: PBAR source status, fixed target operation, Tevatron cryogenic reliability and capacity upgrade, Tevatron Energy upgrade progress and plans, status of the D0 low beta insertion, 1.8 K and 4.7 K refrigeration for low-..beta.. quadrupoles, progress and plans for the LINAC and booster, near term and long term and long term performance improvements.
Date: May 1, 1987
Creator: Childress, S.; Crawford, J.; Dugan, G.; Edwards, H.; Finley, D.A.; Fowler, W.B. et al.
Partner: UNT Libraries Government Documents Department

An experimental study of the SSC (Superconducting Super Collider) magnet aperture criterion

Description: A beam dynamics experiment, performed in the Fermilab Tevatron, that was mainly motivated by planning for the Superconducting Super Collider (SSC) is described. Nonlinearities are introduced in the Tevatron by special sextupoles in order to stimulate the SSC environment. ''Smear'' is one of the parameters used to characterize the deviation from linear behavior. Smear is extracted from experimental data and compared with calculation over a wide range of conditions. The agreement is excellent. The closed orbit at injection trajectory reveal no deterioration even at the highest sextupole excitations. Measurements of the dynamic aperture are in general agreement with prediction. Particles captured on nonlinear resonance islands are directly observed and measurements are performed for the first time. The stability of the islands under tune modulation is investigated. 4 refs., 8 figs.
Date: June 7, 1988
Creator: Merminga, N.; Edwards, D.; Finley, D.; Gerig, R.; Gelfand, N.; Harrison, M. et al.
Partner: UNT Libraries Government Documents Department


Description: This report provides the results of an extensive and important study of the potential for a U.S. scientific program that will extend our knowledge of neutrino oscillations well beyond what can be anticipated from ongoing and planned experiments worldwide. The program examined here has the potential to provide the U.S. particle physics community with world leading experimental capability in this intensely interesting and active field of fundamental research. Furthermore, this capability is not likely to be challenged anywhere else in the world for at least two decades into the future. The present study was initially commissioned in April 2006 by top research officers of Brookhaven National Laboratory and Fermilab and, as the study evolved, it also provides responses to questions formulated and addressed to the study group by the Neutrino Scientific Advisory Committee (NuSAG) of the U.S. DOE and NSF. The participants in the study, its Charge and history, plus the study results and conclusions are provided in this report and its appendices. A summary of the conclusions is provided in the Executive Summary.
Date: January 1, 2007
Partner: UNT Libraries Government Documents Department

A large liquid argon time projection chamber for long-baseline, off-axis neutrino oscillation physics with the NuMI beam

Description: Results from neutrino oscillation experiments in the last ten years have revolutionized the field of neutrino physics. While the overall oscillation picture for three neutrinos is now well established and precision measurements of the oscillation parameters are underway, crucial issues remain. In particular, the hierarchy of the neutrino masses, the structure of the neutrino mixing matrix, and, above all, CP violation in the neutrino sector are the primary experimental challenges in upcoming years. A program that utilizes the newly commissioned NuMI neutrino beamline, and its planned upgrades, together with a high-performance, large-mass detector will be in an excellent position to provide decisive answers to these key neutrino physics questions. A Liquid Argon time projection chamber (LArTPC) [2], which combines fine-grained tracking, total absorption calorimetry, and scalability, is well matched for this physics program. The few-millimeter-scale spatial granularity of a LArTPC combined with dE/dx measurements make it a powerful detector for neutrino oscillation physics. Scans of simulated event samples, both directed and blind, have shown that electron identification in {nu}{sub e} charged current interactions can be maintained at an efficiency of 80%. Backgrounds for {nu}{sub e} appearance searches from neutral current events with a {pi}{sup 0} are reduced well below the {approx} 0.5-1.0% {nu}{sub e} contamination of the {nu}{sub {mu}} beam [3]. While the ICARUS collaboration has pioneered this technology and shown its feasibility with successful operation of the T600 (600-ton) LArTPC [4], a detector for off-axis, long-baseline neutrino physics must be many times more massive to compensate for the low event rates. We have a baseline concept [5] based on the ICARUS wire plane structure and commercial methods of argon purification and housed in an industrial liquefied-natural-gas tank. Fifteen to fifty kton liquid argon capacity tanks have been considered. A very preliminary cost estimate for a 50-kton detector is $100M ...
Date: September 1, 2005
Creator: Finley, D.; Jensen, D.; Jostlein, H.; Marchionni, A.; Pordes, S.; Rapidis, P. A. et al.
Partner: UNT Libraries Government Documents Department