120981188
LARGE-ANGLE PION--PROTON ELASTIC SCATTERING AT HIGH ENERGIES.
124689502
A POSSIBLE SPECTROMETER FOR ACCOMPLISHING A SECONDARY BEAM SURVEY AT NAL.
53129380
Ground-water activation from the upcoming operation of MI40 beam absorber
During the course of normal operation, a particle accelerator can produce radionuclides in the adjacent soil and in the beam line elements through the interactions of accelerated particles and/or secondary particles produced in the beam absorbers, targets, and sometimes elsewhere through routine beam losses. The production and concentration of these radionuclides depends on the beam parameters such as energy, intensity, particle type, and target configuration. The radionuclides produced in the soil can potentially migrate to the ground water. Soil activation and migration to the ground water depends on the details of the local hydrogeology. Generally, very few places such as the beam stops, target stations, injection and extraction sectors can have high enough radiation fields to produce radionuclides in the soil outside the enclosures. During the design, construction, or an upgrade in the intensity of existing beams, measures are taken to minimize the production of activated soil. The only leachable radionuclides known to be produced in the Fermilab soil are {sup 3}H, {sup 7}Be , {sup 22}Na, {sup 45}Ca and {sup 54}Mn and it has been determined that only {sup 3}H, and {sup 22}Na, because of their longer half lives and greater leachabilities, may significantly impact ground water resources.In themore » past, Fermilab has developed and used the Single Resident Well Model (SRWM) to estimate the ground water activation. Recently, the Concentration Model (CM), a more realistic method which depends on the site hydrogeology has been developed to decide the shielding requirements of the high radiation sites, and to calculate the ground water activation and its subsequent migration to the aquifer. In this report, the concentration of radionuclide released to the surface waters and the aquifer around the MI40 beam absorber are calculated. Subsequently, the ultimate limit on the primary proton beam intensity to be aborted on the Main Injector beam absorber is determined.« less
124083721
SOME ASPECTS OF TARGETING SYSTEMS FOR A SLOW EXTRACTED BEAM AT THE AGS.
124267104
DISCUSSION OF POSSIBLE USES OF RF BEAM STRUCTURE IN COUNTER EXPERIMENTS AT NAL.
122023821
Measurement of the double-spin asymmetry ALL for inclusive multi-γ pair production with 200 GeV/c polarized proton beam and polarized proton target
The invariant double-differential cross section, E1E2d6 delta/dp(1)3dp(2)3, and the double-spin asymmetry, A(LL), for inclusive multi-gamma pair production in which gamma-rays came from neutral mesons were measured with a 200 GeV/c longitudinally-polarized proton beam and a longitudinally-polarized proton target. Most of the multi-gamma pairs comes from two-jet type events which are sensitive to partonic interaction. The A(LL) values were found to be consistent with zero. The invariant double-differential cross section for inclusive pi0pi0 production was also measured. These measured cross sections are consistent with LUND Monte Carlo simulations. Using the LUND Monte Carlo simulation package with the Carlitz-Kaur model of spin dependent distribution functions of valence quarks, the A(LL) values have been compared with theoretical predictions of gluon polarization, DELTAG/G. The results put restrictions on the size of DELTAG/G in the region of 0.05 less-than-or-similar-to x less-than-or-similar-to 0.35.
110508272
Performance of the DELPHI small angle tile calorimeter
The DELPHI STIC detector is a lead-scintillator sampling calorimeter with wavelength shifting optical fibers used for light collection. The main goal of the calorimeter at LEP100 is to measure the luminosity with an accuracy better than 0.1%. The detector has been in operation since the 1994 LEP run. Presented here is the performance measured during the 1994-1995 LEP runs, with the emphasis on the achieved energy and space resolution, the long-term stability and the efficiency of the detector. The new bunch-trains mode of LEP requires a rather sophisticated trigger and timing scheme which is also presented. To control the trigger efficiency and stability of the calorimeter channels, a LED-based monitoring system has been developed.
121337614
Absolute in situ energy calibration of luminosity calorimeters in the DELPHI experiment at LEP
Abstract Methods to perform the absolute energy calibration of DELPHI's Small Angle Tagger luminosity calorimeters at LEP are presented and compared. The input was small angle Bhabha scattering events. A significant nonlinearity in the response of the calorimeters was observed. The conjugate gradient method was applied to solve the least squares problem. This method is particularly useful for least squares problems which are large, ill-behaved or even singular, and for cases with a sparse coefficient matrix.
35536172
In-orbit performance of the EPIC-MOS detectors on XMM-Newton
XMM-Newton was launched into space on a highly eccentric 48 hour orbit on December 10th 1999. XMM-Newton is now in its fifth year of operation and has been an outstanding success, observing the Cosmos with imaging, spectroscopy and timing capabilities in the X-ray and optical wavebands. The EPIC-MOS CCD X-ray detectors comprise two out of three of the focal plane instruments on XMM-Newton. In this paper we discuss key aspects of the current status and performance history of the charge transfer ineffiency (CTI), energy resolution and spectral redistribution function (rmf) of EPIC-MOS in its fifth year of operation.
108962738
Performance of the new high precision luminosity monitor of DELPHI
The STIC calorimeter was installed in the DELPHI detector in 1994. The main goal is to measure the luminosity with an accuracy better than 0.1%. The calorimeter was built using the “Shashlik” technique. The light is collected by wavelength shifting fibers and readout by phototetrodes that can operate inside the magnetic field. The detector performance during the 1994–1995 data taking is presented. The different contributions to the systematic error on the luminosity measurement are discussed.
108830204
A CMOS charge sensitive amplifier for silicon strip detectors: Design criteria and test results
Abstract A low noise charge sensitive amplifier has been developed with a commercial CMOS process. We present measurements of the amplifier's performance when used to read out a silicon strip detector exposed to a particle beam. A few prototypes have been exposed to large doses of radiation in order to study the radiation hardness.