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Dijet mass resolution and compensating calorimetry

Description: The calorimetry for SSC detectors has as its role the detection of the basic particles of the Standard Model. Those germane to calorimetry are quarks, photons, electrons, and gluons. Note that all the hadronic entities appear in the calorimetry as jets. The detection of single hadrons belongs to a past era when quark molecules'' were the focus of intense study. Thus, the goal of calorimetry at the SSC must be the study of jets. In particular, one must understand what defines the limits of accur… more
Date: May 1, 1991
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Physics requirements for LHC/SSC calorimetry

Description: The goal of the next generation of collider detectors is to study the origin of electroweak symmetry breaking. The mass scale for this study is roughly 1 TeV. No matter what the details of the mechanism, one can be confident that new phenomena will occur, since weak interactions become strong, i.e., violate partial wave unitarity, at that mass scale. The partial wave amplitude for ee{yields} WW scattering is; ao{approximately}4{phi}/{alpha}{sub w}(M{sub w}/M){sup 2}, ao{approximately}1 if M {ap… more
Date: October 1, 1991
Creator: Green, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of inert material on ZZ mass resolution for H yields ZZ yields eeee

Description: A detector with a modest sized magnetic field volume will, of necessity, have inert material (solenoid coil) in front of the calorimetry. It is therefore crucial to assess the impact of that material on the physics of interest. Since the thickness of material is of order a radiation length, Xo, and only a fraction of a nuclear interaction length, the physics topics concern the EM calorimetry. In this note, a Higgs boson with a wide variety of masses is used as a paradigm of SSC physics. Low mas… more
Date: April 1, 1991
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of radiation damage on Z mass resolution in the process H yields ZZ yields eeee

Description: It is true that a comprehensive understanding of how to translate radiation damage measurements of transmission loss for short time exposures into degradation of detector performance does not exist. A conversion of short term tests into long term exposure needs to be made. Similarly, a conversion of transmission loss into loss of resolution also needs to be made. Finally, the incorporation of a program of periodic calibration into the radiation damage model must also occur before one can assess… more
Date: November 1, 1990
Creator: Green, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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/bar p/p collider physics

Description: This note encompasses a set of six lectures given at the summer school held at Campos Do Jordao in January of 1989 near Sao Paulo, Brazil. The intent of the lectures was to describe the physics of /bar p/p at CERN and Fermilab. Particular attention has been paid to making a self contained presentation to a prospective audience of graduate students. Since large Monte Carlo codes might not be available to all members of this audience, great reliance was placed on ''back of the envelope estimates.… more
Date: March 1, 1989
Creator: Green, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Silicon detector readout system using commercially available items

Description: The basic properties of silicon detectors are briefly noted, including bulk and electrical properties. Thermal and shot noise in front end amplifiers is discussed. The configuration of detectors and preamps is then briefly described. A detector test is described and results are given. (LEW)
Date: May 1, 1986
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Source calibrations and SDC calorimeter requirements

Description: Several studies of the problem of calibration of the SDC calorimeter exist. In this note the attempt is made to give a connected account of the requirements on the source calibration from the point of view of the desired, and acceptable, constant term induced in the EM resolution. It is assumed that a local'' calibration resulting from exposing each tower to a beam of electrons is not feasible. It is further assumed that an in situ'' calibration is either not yet performed, or is unavailable du… more
Date: October 1, 1992
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sampling nonuniformity in the SDC calorimeter EM/HAD boundary

Description: The SDC steel hadronic (HAD) calorimeter absorber structure has been designed to be of low magnetic reluctance, high rigidity, and excellent hermiticity. Transverse scintillator tiles staggered longitudinally allow one to assemble the hadronic calorimeter compartment with no transverse dead areas between tiles. Clearly, the structure affords many advantages, among them hermeticity. The only problem is that, at the boundary of the structure, as at the E boundary, the steel sampling fraction for … more
Date: April 1, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dead material and energy measurements in hadronic calorimeters

Description: Often the question arises as to where is the optimal place to locate [open quotes]dead[close quotes] material in a calorimeter. This material may be needed for structural reasons, for example. There needs to be a quantified answer to the question of what damage this [open quotes]dead[close quotes] material does to the performance of a calorimeter. For the purposes of this note, a hadronic calorimeter (HAD) is characterized by the mean and standard deviation of the energy measurement made by tha… more
Date: January 1, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effects of cracks on calorimeter response in the SDC dogleg'' design

Description: In an initial attempt to set the scale for cracks, the reaction H(800) [yields] ZZ [yields] (q + q) [yields] ([tau]l +[tau]2) [yields] ([rho]l + [nu]i) + ([rho]2 + [nu]2) was studied. The figure of merit was taken to be the Z transverse mass, i.e. the mass of ([rho]1 + 2 + E[sub T]). With no cracks in the coverage save the beam holes at [eta] = 5, this quantity has a fractional spread of [approximately] 12%. The additional contribution of cracks was unfolded in quadrature. Clearly, the scale wh… more
Date: November 1, 1992
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Magnetic fields and SDC endcap scintillator performance

Description: Many detectors designed to operate in colliders contain both magnetic fields, usually solenoids, and scintillators. The former is known to influence the operation of the latter. A first look is taken in this note at the implications of that influence for the SDC detector.
Date: January 1, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Source calibrations and SDC calorimeter requirements

Description: Several studies of the problem of calibration of the SDC calorimeter exist. In this note the attempt is made to give a connected account of the requirements on the source calibration from the point of view of the desired, and acceptable, constant term induced in the EM resolution. It is assumed that a ``local`` calibration resulting from exposing each tower to a beam of electrons is not feasible. It is further assumed that an ``in situ`` calibration is either not yet performed, or is unavailabl… more
Date: October 1, 1992
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Longitudinal information and radiation damage in EM calorimetry

Description: The SCC radiation field is higher than that encountered by previous hadron collider detectors. In particular, the electromagnetic (EM) calorimeter compartment sees the highest radiation dose. Since an EM calorimeter also makes the most precise energy measurement, special care must be lavished on this part of a calorimeter. Previous studies have concentrated on Monte Carlo examinations of 2 longitudinal compartments within the EM which can alleviate radiation damage. Recently, it was realized th… more
Date: February 5, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Missing energy induced by thin hadron calorimetry

Description: It is relatively straightforward to estimate the total, unsegmented, depth required in SSC experiments. Typically depths in the range of 9--11 absorption lengths were specified by the SDC and GEM experiments. With these depths, the induced missing energy signal due to calorimeter leakage was found to be well below the signals caused by light gluinos, and the exterior muon systems were well protected from punch through backgrounds. In certain applications, where calorimetry is inscribed inside t… more
Date: April 1, 1994
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Magnetic field effects on endcap EM calorimetry in SDC

Description: The SDC calorimeter will be immersed in a strong magnetic field in the endcap region because of the solenoid which supplies the SDC tracking field. This flux must be returned through the endcap region of the electromagnetic (EM) and hadronic (HAD) calorimeters. Since magnetic fields are known to induce changes in the light output of plastic scintillator, the endcap will need to be recalibrated once the solenoid is energized. In addition, gradients in the field will create nonuniformities in the… more
Date: January 25, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Dead material and energy measurements in hadronic calorimeters

Description: Often the question arises as to where is the optimal place to locate {open_quotes}dead{close_quotes} material in a calorimeter. This material may be needed for structural reasons, for example. There needs to be a quantified answer to the question of what damage this {open_quotes}dead{close_quotes} material does to the performance of a calorimeter. For the purposes of this note, a hadronic calorimeter (HAD) is characterized by the mean and standard deviation of the energy measurement made by tha… more
Date: January 1, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Optimization of CMS HCAL parameters using hanging file test data

Description: There are 2 basic choices for the magnetic solenoid coil location in large collider experiments. One can place the coil inside the calorimeter radius as in CDF, DO, ATLAS, and SDC. Alternatively, one can place the coil outside the calorimetry as in SLD, ZEUS, and CMS. There are clearly definite advantages to both schemes since different collaborations have chosen different topologies. In this note we examine the consequences of the second choice, which places no significant material in front of… more
Date: June 1, 1994
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effect of azimuthal inert material on the CMS hadron calorimeter

Description: The baseline design for the CMS hadronic calorimeter (HCAL) calls for barrel wedges subtending an azimuthal range of 1/18 of 2 {pi}. These wedges will each have about 1 cm of inert material which is required to make a self supporting structure. Therefore, it is expected that there will be about 2 cm of inert material between active elements in the CMS calorimeter. Since the inner radius of the HCAL modules is at 1.95 m, there is about 3% of the azimuth which is inert and possibly projective. Pr… more
Date: August 4, 1994
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Particle physics

Description: This report discusses the following topics: The standard model -- synthesis and overview; accelerators and other facilities; mapping the SM constituents onto the detectors; a model pp/{bar p}p collider detector; and other experimental techniques.
Date: May 1, 1994
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Magnetic fields and SDC endcap scintillator performance

Description: Many detectors designed to operate in colliders contain both magnetic fields, usually solenoids, and scintillators. The former is known to influence the operation of the latter. A first look is taken in this note at the implications of that influence for the SDC detector.
Date: January 1, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SDC preshower depth and weighting factor using hanging file data

Description: Often inert material exists in front of a calorimeter. If an electromagnetic (EM) shower initiates in this material, and energy is not sampled by the calorimeter, then energy resolution will be degraded. It is crucial to minimize the amount of inert material. Algorithms using a separate readout of the energy early in the shower (a ``preshower`` detector) can also be used to alleviate the reduced performance. This problem has previously been studied using CDF test beam data. In addition, an EGS … more
Date: February 11, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sampling nonuniformity in the SDC calorimeter EM/HAD boundary

Description: The SDC steel hadronic (HAD) calorimeter absorber structure has been designed to be of low magnetic reluctance, high rigidity, and excellent hermiticity. Transverse scintillator tiles staggered longitudinally allow one to assemble the hadronic calorimeter compartment with no transverse dead areas between tiles. Clearly, the structure affords many advantages, among them hermeticity. The only problem is that, at the boundary of the structure, as at the E boundary, the steel sampling fraction for … more
Date: April 1, 1993
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radiation damage in the SDC hadronic endcap calorimeter

Description: Detectors for the SSC face a radiation field which is very dependent on angle. For example, the SDC barrel'' calorimeter can function well for 100 year operation of the SSC running at desip luminosity, while the small angle forward calorimeter'' faces Grad of radiation in the same period. The SDC endcap'' calorimeter is in an intermediate location. One wishes to examine whether it might be possible to use conventional scintillator technology with periodic refurbishment in the endcap- The angula… more
Date: December 1, 1992
Creator: Green, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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