54604551
Beyond the Standard Model Higgs Searches at the Tevatron
The CDF and D0 Collaborations at the Tevatron have an extensive program of searches for 'Beyond-the-Standard-Model' Higgs bosons. Recent results, using data sets corresponding to integrated luminosities of up to 4.2 fb{sup -1}, from such searches are reported. Good agreement between data and Standard Model backgrounds is found in all of the various final states examined. We thus proceed to set limits at 95% Confidence Level (C.L.).
124663512
Energy Resolution of a Prototype Lead Tungstate Crystal Matrix with Vacuum Phototriode Readout for the CMS Endcap Electromagnetic Calorimeter
Data obtained in June 1998 from a 3x3 array of PbWO4 in the H4 testbeam indicate that an energy resolution better than 0.5% at 100GeV can be obtained from a matrix of PbWO4 endcap crystals with vacuum phototriode readout. These data are the first obtained for ECAL endcap shaped crystals and used crystals 220mm long with 24.7x24.7mm 2 front face. Tests with a full sized super-crystal, a 5x5 array of fullsized crystals (28.6x28.6mm 2 front face), will be performed in summer 1999.
120752441
Observation of the UV scintillation light from high energy electron showers in liquid xenon
The UV scintillation light in liquid xenon has been observed using silicon drift photodiodes. Measurements were carried out in a rectangular light cell of dimentions 7.4 × 7.4 × 60 cm3 using 5 GeV electrons. The photodiodes and the preamplifiers were immersed in the liquid. A high quantum efficiency for 175 nm UV light has been measured. The scintillation light yield is found to be (1.5 ± 0.6) × 104 photons per MeV of energy deposited in liquid xenon. A light attenuation lenght of ≈ 40 cm has been measured.
94093096
UV quantum efficiencies of organic fluors
The need for, and benefits of using, wavelength shifters with certain dark matter scintillator detectors is discussed. The dependence of conversion efficiency on thickness and incident wavelength is extensively investigated for evaporated coatings of p-terphenyl and tetraphenyl butadiene, and for plastic waveshifters based upon p-terphenyl. For the latter the effect of varying the p-terphenyl concentration is studied and some factors which must be considered when developing them for use in the UV are also discussed.
14010060
Initial Tests on First Full-size ECAL Endcap Crystals
At the end of last year the first full size ECAL endcap crystals were delivered to CERN.Thirty in number, they were produced to the final geometrical specifications; 220mm long with a rear square face of 30mm and a front square face of 28.6mm. All were delivered polished. The visual inspection , dimension, transmission, light yield and light yield uniformity tests carried out since are discussed , with particular emphasis on the light yield uniformity. The results are very encouraging. suggesting that the endcap crystals will not need uniformisation.
17593732
Standard Model Higgs Search in the Four Jet Channel at LEP
The Standard Model Higgs boson was searched for at LEP, by the four collaborations in the year 2000, at centre-of-mass energies from 200-209GeV. An excess of events, potentially compatible with the production of a Higgs boson of mass ~115GeV was observed, largely in the four-jet channel. The search in this channel is discussed in this letter.
17032836
Radiation Hardness of CCD Vertex Detectors for the ILC
Results of detailed simulations of the charge transfer inefficiency of a prototype CCD chip are reported. The effect of radiation damage in a particle detector operating at a future accelerator is studied by examining two electron trap levels, 0.17 eV and 0.44 eV below the bottom of the conduction band. Good agreement is found between simulations using the ISE-TCAD DESSIS program and an analytical model for the 0.17 eV level. Optimum operation is predicted to be at about 250 K where the effects of the traps is minimal which is approximately independent of readout frequency. This work has been carried out within the Linear Collider Flavour Identification (LCFI) collaboration in the context of the International Linear Collider (ILC) project.
126252051
Understanding and calibrating the DS-ECal for T2K's ND280