118717401
Simultaneous observations of extensive air showers and underground muons at Soudan 2
We have built a small proportional tube air shower array on the surface above the Soudan 2 proton decay detector in Soudan, Minnesota, USA. This array, in coincidence with the underground detector, allows simultaneous surface and underground observations of high energy cosmic ray showers. These observations, still in their initial stages, may eventually be able to provide information about the composition of cosmic ray primaries in the knee'' region of the energy spectrum. 4 refs.
952390
Search for flavor-changing non-standard neutrino interactions by MINOS
We report new constraints on flavor-changing non-standard neutrino interactions from the MINOS experiment, in which neutrino versus antineutrino interactions can be distinguished on an event-by-event basis. We analyzed a combined set of beam neutrino and antineutrino data from the well-understood NuMI beam, and found no evidence for deviations from standard neutrino mixing. The observed energy spectra constrain the non-standard neutrino interactions parameter to the range −0.20
40454478
The MINOS scintillator calorimeter system
The MINOS detectors will use extruded plastic scintillator strips, which are readout by wavelength-shifting fibres coupled to multi-pixel photodetectors. This technique provides excellent energy and spatial resolution. The MINOS detectors are described in detail along with results from the light output tests.
29520771
Search for magnetic monopoles with the Soudan 2 detector.
A search for grand unified theory magnetic monopoles making highly ionizing tracks in argon gas has been conducted using the Soudan 2 nucleon decay detector. This underground detector is a large fine-grained tracking calorimeter comprised of long drift tubes read out by proportional wires. No monopole candidates were observed in data taken over almost three years, yielding an upper flux limit of 8.7{times}10{sup {minus}15} cm{sup {minus}2}s{sup {minus}1}sr{sup {minus}1} for monopole velocities of {beta}{gt}2{times}10{sup {minus}3}.
5924748
Testing Lorentz invariance and CPT conservation with NuMI neutrinos in the MINOS near detector.
A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by the effective field theory called the standard-model extension. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame. Upper limits on the magnitudes of the Lorentz and CPT violating terms in the standard-model extension lie between 10(-4) and 10(-2) of the maximum expected, assuming a suppression of these signatures by a factor of 10(-17).
41110005
Ultrahigh energy cosmic ray composition from surface air shower and underground muon measurements at Soudan 2.
The Soudan 2 experiment has performed time-coincident cosmic ray air shower and underground muon measurements. Comparisons to Monte Carlo predictions show that such measurements can make statistically significant tests of the primary composition in the knee region of the cosmic ray spectrum. The results do not support any significant increase in the average primary mass with energy in the range of {similar_to}10{sup 4} TeV per nucleus. Some systematic uncertainties remain, however, particularly in the Monte Carlo modeling of the cosmic ray shower.
11803447
Development of Large Area Integrated Silicon Tracking Elements for the LHC Luminosity Upgrade
A natural upgrade of the CERN LHC would be to increase the luminosity to 1035 cm-2s-1. For charged particle tracking at this Super-LHC, all-silicon systems are considered appropriate. For tracking in an upgraded ATLAS detector, outside a radius of 20 cm, large area integrated elements ("staves") containing silicon strip detectors are under design and development. Each stave would hold of order 30 individual modules and contain integrated electrical services, mechanical support, and cooling. Prototype tests of such staves are reported here including studies of noise, interference, and a comparison of power distribution by parallel and serial current flow. Mechanical design and simulation on full length staves are presented as well.
116316991
Lie theory and separation of variables. 8. Semisubgroup coordinates for Psi tt - Delta 2Psi = 0
110095326
The Cleo III silicon vertex detector
The CLEO collaboration has embarked on an ambitious upgrade of the CLEO detector to match the upgrade of the CESR accelerator to luminosities of 2 × 10 33 cm −2 sec −1 . This will bring a factor ten improvement in the measurement of rare B decays and hence, increased sensitivity to physics at high mass scales and also the possibility of measuring CP violation. The upgrade includes a new four layer double-sided silicon detector. Each double-sided silicon wafer is 2.6 cmx 5.1 cm × 300 μ m . To maximize solid angle coverage with minimal material in the detector volume the detector chains are very long, up to 5 detectors per electronic readout channel, resulting in large series resistance and large detector capacitance. Moderate backgrounds permit the electronics to operate with a 1–3 μ s shaping time. A new front-end low noise preamplifier is being developed to maximize the signal to noise ratio, along with a modified SVX chip used for analog to digital conversion and sparsification. The detectors are connected to the electronics hybrid by a thin double sided kapton flex circuit. The length of the detector chains also requires novel mechanical support structures — CVD diamond beams axe the baseline solution. We are currently near the end of the prototype stage for all aspects for the project and will move into production by late summer. The detector will be installed in early 1998.
107371126
MPS Data Acquisition System
A description is given of the data acquisition system used with the multiparticle spectrometer facility at Brookhaven. Detailed information is provided on that part of the system which connects the detectors to the data handler; namely, the detector electronics, device controller, and device port optical isolator. (GHT)
55946508
Fluorocarbon evaporative cooling developments for the ATLAS pixel and semiconductor tracking detectors
We report on the development of evaporative fluorocarbon cooling for the ATLAS Pixel and SemiConductor Tracker (SCT) detectors. Data are presented from cooling studies on representative prototype Pixel and SCT detector thermo-structures, using perfluoro-npropane (C3F8), -butane (C4F10), trifluoro-iodo-methane (CF3I) and custom C3F8/C4F10 mixtures. Thermophysical properties were calculated for custom mixtures. For most of the structures tested at full projected power dissipation, operation of silicon detector substrates at temperatures below –7oC (required for 10 year lifetime in the radiation environment of LHC) should be possible, albeit in some cases with increases in inner diameter (I.D.) of the coolant tubes from those of the present series of prototypes. Heat transfer coefficients in the range 2-5.103 Wm-2K-1 have been measured in a 3.6 mm I.D. heated tube dissipating 100 Watts close to the full equivalent power (~110 W) of a barrel SCT detector “stave” over a range of power dissipations and mass flows in the above fluids. Aspects of full-scale evaporative cooling circulator design for the ATLAS experiment are discussed, together with plans for future development.