Comparison of Fiber Polishing Techniques

Office of Scientific and Technical Information (OSTI) (1999)

Authors:

Pierrick Hanlet, Matthew Marcus, Elizabeth Gallas

Space charge in ionization detectors and the NA48 electromagnetic calorimeter

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 421:1-2 (1999) 75-89

Authors:

S Palestini, GD Barr, C Biino, P Calafiura, A Ceccucci, C Cerri, JC Chollet, M Cirilli, J Cogan, F Costantini, S Crépé, D Cundy, R Fantechi, L Fayard, G Fischer, A Formica, PL Frabetti, W Funk, A Gianoli, S Giudici, A Gonidec, B Gorini, G Govi, L Iconomidou-Fayard, V Kekelidze, W Kubischta, S Luitz, I Mannelli, M Martini, I Mikulec, A Norton, J Ocariz, D Schinzel, M Sozzi, G Tatishvili, A Tkatchev, G Unal, M Velasco, O Vossnack, H Wahl

Abstract:

The subject of space charge due to positive ions slowly moving in parallel plate ionization chambers is considered. A model for the degradation of the detector response is developed, with particular emphasis on electromagnetic calorimeters .The topics discussed include: (a) the stationary; (b) the time dependent cases; (c) the limit of very large space charge; (d) the electric field dependence of the electron drift velocity; (e) the effect of longitudinal development of showers; (f ) the behaviour of the average reductions of response; and (g) the non-uniformity of response for different positions of the shower axis inside the cell defined by the electrodes. The NA48 calorimeter is used as application and for comparison of results. © 1999 Elsevier Science B.V. All rights reserved.

Evaluation of the LEP Centre-of-Mass Energy Above the W-Pair Production Threshold

ArXiv hep-ex/9901002 (1999)

Searches for scalar top and scalar bottom quarks in e+e- interactions at 161 GeV ≤ √s ≤ 183 GeV

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 445:3-4 (1999) 428-438

Authors:

M Acciarri, O Adriani, M Aguilar-Benitez, S Ahlen, J Alcaraz, G Alemanni, J Allaby, A Aloisio, MG Alviggi, G Ambrosi, H Anderhub, VP Andreev, T Angelescu, F Anselmo, A Arefiev, T Azemoon, T Aziz, P Bagnaia, L Baksay, S Banerjee, SW Banerjee, K Banicz, A Barczyk, R Barillère, L Barone, P Bartalini, A Baschirotto, M Basile, R Battiston, A Bay, F Becattini, U Becker, F Behner, J Berdugo, P Berges, B Bertucci, BL Betev, S Bhattacharya, M Biasini, A Biland, GM Bilei, JJ Blaising, SC Blyth, GJ Bobbink, R Bock, A Böhm, L Boldizsar, B Borgia, D Bourilkov, M Bourquin, S Braccini, JG Branson, V Brigljevic, IC Brock, A Buffini, A Buijs, JD Burger, WJ Burger, J Busenitz, A Button, XD Cai, M Campanelli, M Capell, G Cara Romeo, G Carlino, AM Cartacci, J Casaus, G Castellini, F Cavallari, N Cavallo, C Cecchi, M Cerrada, F Cesaroni, M Chamizo, YH Chang, UK Chaturvedi, M Chemarin, A Chen, G Chen, GM Chen, HF Chen, HS Chen, X Chereau, G Chiefari, CY Chien, L Cifarelli, F Cindolo, C Civinini, I Clare, R Clare, G Coignet, AP Colijn, N Colino, S Costantini, F Cotorobai, B de la Cruz, A Csilling, TS Dai, R D'Alessandro, R de Asmundis

Abstract:

Searches for scalar top and scalar bottom quarks have been performed at center-of-mass energies between 161 GeV and 183 GeV using the L3 detector at LEP. No signal is observed. Model-independent limits on production cross sections are determined for the two decay channels t̃1 → cχ̃0 1 and b̃1 → b χ̃0 1. Within the framework of the Minimal Supersymmetric extension of the Standard Model mass limits are derived. For mass differences between t̃1 and χ̃0 1 greater than 10 GeV a 95% C.L. limit of 81.5 GeV is set on the mass of the Supersymmetric partner of the left-handed top. A supersymmetric partner of the left-handed bottom with a mass below 80 GeV is excluded at 95% C.L. if the mass difference between b̃1 and χ̃1 is greater than 20 GeV. © 1999 Published by Elsevier Science B.V. All rights reserved.

Dijet mass spectrum and a search for quark compositeness in (p)p collisions at sqrt(s) = 1.8 TeV

Physical Review Letters 82:12 (1999) 2457-2462

Authors:

B Abbott, M Abolins, V Abramov, BS Acharya, I Adam, DL Adams, M Adams, S Ahn, H Aihara, GA Alves, N Amos, EW Anderson, R Astur, MM Baarmand, VV Babintsev, L Babukhadia, A Baden, V Balamurali, B Baldin, S Banerjee, J Bantly, E Barberis, P Baringer, JF Bartlett, A Belyaev, SB Beri, I Bertram, VA Bezzubov, PC Bhat, V Bhatnagar, M Bhattacharjee, N Biswas, G Blazey, S Blessing, P Bloom, A Boehnlein, NI Bojko, F Borcherding, C Boswell, A Brandt, R Breedon, R Brock, A Bross, D Buchholz, VS Burtovoi, JM Butler, W Carvalho, D Casey, Z Casilum, H Castilla-Valdez, D Chakraborty, SM Chang, SV Chekulaev, LP Chen, W Chen, S Choi, S Chopra, BC Choudhary, JH Christenson, M Chung, D Claes, AR Clark, WG Cobau, J Cochran, L Coney, WE Cooper, C Cretsinger, D Cullen-Vidal, MAC Cummings, D Cutts, OI Dahl, K Davis, K De, K Del Signore, M Demarteau, D Denisov, SP Denisov, HT Diehl, M Diesburg, G Di Loreto, P Draper, Y Ducros, LV Dudko, SR Dugad, A Dyshkant, D Edmunds, J Ellison, VD Elvira, R Engelmann, S Eno, G Eppley, P Ermolov, OV Eroshin, VN Evdokimov, T Fahland, MK Fatyga, S Feher, D Fein, T Ferbel, G Finocchiaro

Abstract:

Using the DZero detector at the 1.8 TeV pbarp Fermilab Tevatron collider, we have measured the inclusive dijet mass spectrum in the central pseudorapidity region |eta_jet| < 1.0 for dijet masses greater than 200 Gev/c^2. We have also measured the ratio of spectra sigma(|eta_jet| < 0.5)/sigma(0.5 < |eta_jet| < 1.0). The order alpha_s^3 QCD predictions are in good agreement with the data and we rule out models of quark compositeness with a contact interaction scale < 2.4 TeV at the 95% confidence level. © 1999 The American Physical Society.