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Electron identification in the CDF (Collider Detector at Fermilab) central calorimeter

Description: Efficient identification of electrons both from W decay and QCD heavy flavour production has been achieved with the CDF Central Calorimeter, which is a lead -- scintillator plate calorimeter incorporating tower geometry. The fine calorimetry granularity (0.1 /times/ 0.26 in /eta/, /phi/ space) allows identification of electrons well within the typical jet cone and is wholly sufficient for the measurement of the isolation of electrons from W decay. With minor improvements, such a detector is a realistic option for electron identification in the central rapidity region at the SSC. 1 ref., 7 figs.
Date: January 1, 1989
Creator: Proudfoot, J.
Partner: UNT Libraries Government Documents Department

W boson production in /bar p/p collisions at. sqrt. s = 1. 8 TeV

Description: The cross section for the production and subsequent decay of the W Intermediate Vector boson to electron and neutrino has been measured in ..sqrt..s = 1.8 TeV /bar p/p collisions using the CDF Collider Detector at Fermilab. For this measurement, W events were identified from the large missing transverse energy associated with the unseen neutrino and an electromagnetic cluster passing rather loose electron criteria. 22 events passing the selection missing transverse energy greater than 25 GeV and electron transverse energy greater than 15 GeV were observed in a sample of 25nb/sup /minus/1/ yielding a sigma /center dot/ B = 2.6 /+-/ 0.6 /+-/ 0.5nb. This report agrees well with a parallel analysis based primarily on the identification of isolated electron and is in excellent agreement with theoretical predictions. 12 refs., 7 figs.
Date: January 1, 1988
Creator: Proudfoot, J.
Partner: UNT Libraries Government Documents Department

Radiation tolerance implications for the mechanical design of a scintillator calorimeter for the SSC

Description: This paper discusses the issue of radiation damage in a sampling scintillator calorimeter with regard to the mechanical and optical design of such a device. Radiation damage is inevitable in some regions of the detector and the different damage and recovery time constants are compared to anticipated calibration data from W Z Boson decays. Some plausible values for safety factors in the initial design are given. 5 refs., 1 fig.
Date: January 1, 1990
Creator: Proudfoot, J.
Partner: UNT Libraries Government Documents Department

Calorimetry using organic scintillators, 'a sideways perspective'.

Description: Over the last two decades, calorimetry baaed on organic scintillators has developed into an excellent technology for many experimental situations in high energy physics. The primary difficulty, that of extracting the light signals, has benefited from two milestone innovations. The first was the use of wavelength-shifting bars to allow light to be efficiently collected from large areas of scintillator and then readily piped to a readout device. The second of these was the extension of this approach to plastic wavelength-shifting optical fibers whose great flexibility and small diameter allowed a minimum of detector volume to be compromised by the read-out. These two innovations coupled with inventiveness have produced many varied and successful calorimeters. Equal response to both hadronic and electromagnetic showers can be realized in scintillator-based calorimeters. However, in general this is not the case and it is likely that in the search for greater performance, in the future, combined tracking and calorimeter systems will be required.
Date: September 10, 1999
Creator: Proudfoot, J.
Partner: UNT Libraries Government Documents Department

QCD physics in Atlas at the large hadron collider.

Description: The Large Hadron Collider (LHC) is a proton-proton collider with a 14 TeV center of mass energy. The design luminosity is 10{sup 34} cm{sup -1}s{sup -1} with beam collisions separated by 25 ns. The initial operation for physics will take place at a luminosity of 10{sup 33}cm{sup -1}s{sup -1} and it is expected that the integrated luminosity delivered in the first year will be 10 fb{sup -1}. This integrated luminosity will result in very large event samples for most processes, for example: {approx}10{sup 8} leptonic W decays, 10{sup 4} {gamma}'s with E{sub t} > 500GeV and 10{sup 4} jets with E{sub t} > 1TeV. As a result of the high statistics event samples, the understanding of most QCD processes at 14TeV will be systematics limited after the first year of running. The Atlas detector [1] is a general purpose detector designed to be sensitive to the many physics processes which are expected at the LHC. It contains high performance tracking using silicon detectors and a transition radiation tracker in a 2 Tesla solenoidal magnetic field, a high resolution electromagnetic calorimeter based on lead-liquid argon, a hadron calorimeter based on steel-scintillator and Cu/W-liquid argon, and a large instrumented air-core toroid magnet system for muon measurement. The basic performance characteristics of these systems are given in Table 1.
Date: October 7, 2002
Creator: Proudfoot, J.
Partner: UNT Libraries Government Documents Department

A first simulation study of the barrel-endcap transition region in a calorimeter of the scintillator tile design

Description: We have made a first study of the calorimetric response to 10 GeV/c charged pions in the transition region between barrel and endcap for the scintillator-tile design pursued at Argonne National Laboratory using the simulation program ANLSIM. For (very nearly) projective tower orientations in the barrel, the crack appears deep within a narrow angular range, causing a loss of the response in that region up to 40%. Pointing the towers onto the beam axis 35 cm or more away from the nominal-interaction point leads to a shortened depth of the barrel-endcap crack as seen by particles incident from the interaction region, cutting the maximum loss down by almost one half. The worsening of the resolution follows the same trend. Introduction of a solenoidal coil in front of the calorimeter causes an overall degradation of the response by an amount nearly comparable to the effect of the crack. Electrons of the same incident momentum are more strongly affected by the coil than pions but see only a much narrower region of degradation by the crack. 15 refs., 6 figs., 2 tabs.
Date: August 24, 1990
Creator: Proudfoot, J. & Trost, H.J.
Partner: UNT Libraries Government Documents Department

Estimation of hadronic and EM resolution for scintillator plate calorimeter configurations

Description: CALOR89 Simulation code has been used to estimate the hadronic and electromagnetic resolutions for the various scintillator plate calorimeter configurations. The goal of this study was to determine the optimum combination of Lead and Iron based calorimeter, which retains compensation and linearity. The configurations considered are Lead/Scintillator and Fe/Scintillator and their combinations. Ultimately, we hope to test these configurations in the hanging file beam test at Fermilab in this spring. 12 figs., 4 tabs.
Date: January 1, 1991
Creator: Job, P.K. & Proudfoot, J.
Partner: UNT Libraries Government Documents Department

Measurement of radiation dose using radiochromic film

Description: We have irradiated samples of radiochromic film to doses between 0.005 and lMrad in a Co[sup 60] facility at ANL. The doses computed using the manufacturer's calibration curves for the absorption at 600 and 510 nm have been compared with the dose obtained from ion chamber measurements. Excellent agreement is obtained and high precision can be maintained by baseline measurement of the films prior to irradiation, appropriate choice of film and wavelength used.
Date: November 24, 1992
Creator: Jankowski, D.J. & Proudfoot, J.
Partner: UNT Libraries Government Documents Department

Measurement of radiation dose using radiochromic film

Description: We have irradiated samples of radiochromic film to doses between 0.005 and lMrad in a Co{sup 60} facility at ANL. The doses computed using the manufacturer`s calibration curves for the absorption at 600 and 510 nm have been compared with the dose obtained from ion chamber measurements. Excellent agreement is obtained and high precision can be maintained by baseline measurement of the films prior to irradiation, appropriate choice of film and wavelength used.
Date: November 24, 1992
Creator: Jankowski, D. J. & Proudfoot, J.
Partner: UNT Libraries Government Documents Department

The SDC central calorimeter

Description: An overview of the calorimeter being designed and constructed by Solenoidal Detector Collaboration (SDC) for use at the Superconducting SuperCollider is presented. The collaboration have chosen to build a sampling calorimeter using scintillating tile with wavelength-shifter fiber readout as the detector medium, and absorber media of lead and iron for the electromagnetic and hadronic compartments. This choice was based on a substantial amount of R&D and Monte Carlo simulation calculations, which showed that it both met the necessary experimental specifications in addition to being a cost effect design.
Date: November 1, 1992
Creator: Proudfoot, J. & Collaboration, The SDC
Partner: UNT Libraries Government Documents Department

Experiences with stacking the first four ATLAS submodules at Argonne

Description: This note is to review our experience at Argonne with assembling the first four sumodules constructed at this location. We will try to cover all of the experiences, and at the end add some comments about changes that were incorporated into the current modules, and suggested changes that may be incorporated into future modules.
Date: February 22, 1996
Creator: Hill, N.; Proudfoot, J.; Wood, K.; Balka, L.; Keyser, C. & Caird, A.
Partner: UNT Libraries Government Documents Department

Plate stamping of masterplates for the Tile-Cal hadronic calorimetric for ATLAS detector at CERN

Description: Various methods have been explored for the fabrication of the large trapezoidal plates used in the construction of the Tile-Cal hadronic calorimeter for ATLAS. The options include die stamping, laser cutting, waterjet cutting, plasma arc cutting, and a combination of machining and laser cutting. Very early in the program, the Argonne group began investigating the possibility of die stamping the master plates. At that time it was felt that two dies would be necessary to achieve the accuracy required. Quotations were received for dies for both the master and spacer plates. Concern was expressed by many members of the collaboration that due to the very precise tolerances required, die stamping, using standard dies, would not be adequate. Fine blanking techniques were felt to be adequate, but were cost prohibitive. Two methods were finally used for the initial cutting of prototype plates, laser cutting and die stamping. Only the die stamping, will be reviewed here.
Date: May 16, 1996
Creator: Hill, N. F.; Petereit, E.; Wood, K. & Proudfoot, J.
Partner: UNT Libraries Government Documents Department

Fiber-tile optical studies at Argonne

Description: In support of a fiber-tile calorimeter for SDC, we have done studies on a number of topics. The most basic problems were light output and uniformity of response. Using a small electron beam, we have studied fiber placement, tile preparation, wrapping and masking, fiber splicing, fiber routing, phototube response, and some degradation factors. We found two configurations which produced more light output than the others and reasonably uniform response. We have chosen one of these to go into production for the EM test module on the basis of fiber routing for ease of assembly of the calorimeter. We have also applied some of the tools we developed to CDF end plug tile uniformity, shower max testing and development for a couple of detectors, and development of better techniques for radiation damage studies. 18 figs.
Date: July 23, 1991
Creator: Underwood, D.G.; Morgan, D.J. & Proudfoot, J.
Partner: UNT Libraries Government Documents Department

Master plate production for the tile calorimeter extended barrel modules.

Description: Approximately 41,000 master plates (Fig. 1) are required for the Extended Barrel Hadronic Calorimeter for the ATLAS experiment at the LHC. Early in the R&D program associated with the detector, it was recognized that the fabrication of these steel laminations was a significant issue, both in terms of the cost to produce these high precision formed plates, as well as the length of time required to produce all plates for the calorimeter. Two approaches were given serious consideration: laser cutting and die stamping. The Argonne group was a strong supporter of the latter approach and in late 1995 initiated an R&D program to demonstrate the feasibility and cost effectiveness of die stamping these plates by constructing a die and stamping approximately 2000 plates for use in construction of three full size prototype modules. This was extremely successful and die stamping was selected by the group for production of these plates. When the prototype die was constructed it was matched to the calorimeter envelope at that time. This subsequently changed. However with some minor adjustments in the design envelope and a small compromise in terms of instrumented volume, it became possible to use this same die for the production of all master plates for the Tile Calorimeter. Following an extensive series of discussions and an evaluation of the performance of the stamping presses available to our collaborators in Europe, it was decided to ship the US die to CERN for use in stamping master plates for the barrel section of the calorimeter. This was done under the supervision of CERN and JINR, Dubna, and carried out at the TATRA truck plant at Koprivinice, Czech Republic. It was a great success. Approximately 41,000 plates were stamped and fully met specification. Moreover, the production time was significantly reduced by avoiding the need of ...
Date: March 10, 1999
Creator: Guarino, V.J.; Hill, N.; Petereit, E.; Price, L.E.; Proudfoot, J. & Wood, K.
Partner: UNT Libraries Government Documents Department

ANL/WSU radiation damage studies

Description: We report preliminary results for the radiation hardness of (polystryrene) plastic scintillator stacks using a spectrum of energy hardened neutrons from a MARK-III TRIGA reactor. The total dose ranged from 100 KRad to 3MRad. The corresponding fluence was 3.8 {times} 10{sup 13} to 3.8 {times} 10{sup 14} (n/cm/cm) with the gamma contribution on the order 2--3% (of fluence). The measurements used Li-6, Li-7 Thermo-luminescence dosimeters. Radiochromic/GaF- Chromic film, and activated foils simultaneously allowing an inter-comparison of these various methods of dosimetry.
Date: December 31, 1993
Creator: Jankowski, D.; Lopiano, D.; Proudfoot, J.; Underwood, D.; Miles, L.; Neidiger, J. et al.
Partner: UNT Libraries Government Documents Department

Proposal for the completion of outstanding work on the mechanical absorber structure of SDC barrel electromagnetic calorimeter

Description: The High Energy Physics Division at Argonne National Laboratory and Westinghouse Science and Technology Center, Pittsburgh Pennsylvania have worked jointly on a scintillating tile/fiber calorimeter with the SDC collaboration since it`s inception in 1989. During the design and prototyping phase of the last three years, we have particularly worked on the development of an innovative cast lead approach to the absorber and the associated design of tile/fiber packaging for the barrel electromagnetic calorimeter (EMC). A full scale prototype program was initiated in 1992 to construct four EMC castings to be mated to respective steel hadronic wedges fabricated in China and presently at Fermilab. This proposal we outline in detail both the tasks that we have completed and those that we propose to complete in order to make the extensive investment in this technology useful to others in the field.
Date: November 17, 1993
Creator: Guarino, V.; Hill, N.; Kicmal, T.; Nasiatka, J.; Petereit, E.; Price, L. et al.
Partner: UNT Libraries Government Documents Department

Production summary for extended barrel module fabrication at Argonne for the ATLAS tile calorimeter.

Description: The Tile Calorimeter is one of the main hadronic calorimeters to be used in the ATLAS experiment at CERN [1,2]. It is a steel/scintillator sampling calorimeter which is built by stacking 64 segments in azimuth and 3 separate cylinders to provide a total structure whose length is approximately 12m and whose diameter is a little over 8.4m. It has a total weight of about 2630 metric tons. Important features of this calorimeter are: A minimum gap (1.5mm) between modules in azimuth; Pockets in the structure to hold the scintillator tiles; Recessed channels at the edges of the module into which the readout fibers will sit; and Holes in the structure through which a radioactive source will pass. The mechanical structure for one of the 3 calorimeter sections, the Extended Barrel (EBA) was constructed at Argonne. A schematic of the calorimeter sampling structure and the layout of one of the 64 segments, termed a module, are shown in figure 1. Each module comprises mechanically of a precision machined, structural girder to which 10 submodules are bolted. One of these submodules, the ITC, has a customized shape to accommodate services for other detector elements. Each submodule weighs 850Kg and the assembled mechanical structure of the module weighs approximately 9000Kg (a fully instrumented Extended Barrel modules weighs {approx}9600Kg). A crucial issue for the tile calorimeter assembly is the minimization of the un-instrumented gap between modules when they are stacked on top of each other during final assembly. The design goal was originally 1mm gap which was eventually relaxed to 1.5mm following a careful evaluation of all tolerances in the construction and assembly process as shown in figure 2 [3]. Submodules for this assembly were produced at 4 locations [4] using tooling and procedures which were largely identical [5]. An important issue was the ...
Date: November 14, 2007
Creator: Guarino, V.; Hill, N.; Petereit, E.; Skrzecz, F.; Wood, K.; Proudfoot, J. et al.
Partner: UNT Libraries Government Documents Department

High Energy Physics Division semiannual report of research activities, January 1, 2003 - June 30, 2003.

Description: This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1 through June 30, 2003. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of Division publications and colloquia are included.
Date: January 27, 2004
Creator: Spinka, H.; Nodulman, L.; Goodman, M.; Repond, J.; Cadman, R.; Ayres, D. S. et al.
Partner: UNT Libraries Government Documents Department

Simulation of hanging file experiments with CALOR89

Description: This note presents the comparison of CALOR89 simulation with the hanging file'' test measurements conducted at Fermilab during the period of Sep 91--Jan 92. The purpose of this study is to benchmark CALOR89 code against the experimental data to enhance its reliability and predictive power. Seven hanging file configurations were simulated. The measured values of e/{pi} ratio (the ratio of electron to pion signal at the same energy), hadronic and electromagnetic resolutions were compared with the simulations. The depth profiles of the hadronic and electromagnetic showers are also compared.
Date: January 1, 1992
Creator: Job, P.K.; Price, L.E.; Proudfoot, J. (Argonne National Lab., IL (United States). High Energy Physics Div.); Handler, T. (Tennessee Univ., Knoxville, TN (United States)) & Gabriel, T.A. (Oak Ridge National Lab., TN (United States))
Partner: UNT Libraries Government Documents Department

Simulation studies for design optimisation of a scintillator plate calorimeter

Description: Results on simulations studies relating to the optimisation of a sampling scintillator plate calorimeter for an SSC detector system are presented. These studies show that whereas a compensating sampling geometry can be obtained using a variety of configurations using either lead or depleted uranium as the principal absorber, no configuration based on a pure iron absorber is compensating. Unlike in a lead system, delayed energy release from long lived shower products produced in a uranium system pose a serious pile up problem. Therefore we advocate the use of lead as the principal absorber in this calorimeter. Work on optimisation of the mechanical structure is in progress and results are presented on issues such as structural support, tolerances and on the degradation in response due to other detector material within the volume of the calorimeter. 8 refs., 16 figs.
Date: January 1, 1990
Creator: Proudfoot, J.; Job, P.K.; Trost, H.J. (Argonne National Lab., IL (USA)); Handler, T. (Tennessee Univ., Knoxville, TN (USA)) & Gabriel, T. (Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department

Systematic effects in CALOR simulation code to model experimental configurations

Description: CALOR89 code system is being used to simulate test beam results and the design parameters of several calorimeter configurations. It has been bench-marked against the ZEUS, D{theta} and HELIOS data. This study identifies the systematic effects in CALOR simulation to model the experimental configurations. Five major systematic effects are identified. These are the choice of high energy nuclear collision model, material composition, scintillator saturation, shower integration time, and the shower containment. Quantitative estimates of these systematic effects are presented. 23 refs., 6 figs., 7 tabs.
Date: March 27, 1991
Creator: Job, P.K.; Proudfoot, J. (Argonne National Lab., IL (USA)); Handler, T. (Tennessee Univ., Knoxville, TN (USA). Dept. of Physics and Astronomy) & Gabriel, T.A. (Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department

High Energy Physics Division semiannual report of research activities, January 1, 2002 - June 30, 2002.

Description: This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1 through June 30, 2002. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of Division publications and colloquia are included.
Date: January 31, 2003
Creator: Spinka, H. M.; Nodulman, L. J.; Goodman, M. C.; Repond, J.; Cadman, R.; Ayres, D. S. et al.
Partner: UNT Libraries Government Documents Department

High Energy Physics Division semiannual report of research activities, January 1, 1999--June 30, 1999.

Description: In the period January--June 1999 accomplishments for the ANL-HEP division medium energy physics project consisted of the completion of two papers on past Saclay experiments, the beginning of analysis of recent data from the Crystal Ball measurements at the Brookhaven AGS, and preparations for a RHIC polarimeter. Two papers on Saclay pp elastic scattering data were completed by an ANL physicist, submitted and accepted in Physical Review. Results for the spin observable P - A{sub oono} = A{sub ooon} = A{sub y} at over 30 beam kinetic energies between 800 and 2,800 MeV and C.M. angles from about 70{degree}--110{degree} are described. A total of 919 new data points are presented in these articles. The energy dependence at fixed c.m. angles appears smooth, with no evidence for rapid energy-dependent structure. Work has also begun on two additional papers at Argonne and on others at Saclay.
Date: January 26, 2000
Creator: Spinka, H.; Nodulman, L.; Goodman, M.C.; Repond, J.; Proudfoot, J.; Underwood, D. et al.
Partner: UNT Libraries Government Documents Department