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Impact of future HERA data on the determination of proton parton distribution functions using the ZEUS QCD fit

Aip Conference Proceedings 792 (2005) 396-402

Abstract:

The high precision and large kinematic coverage of the data from the HERA-I running period (1994-2000) have already allowed precise extractions of proton parton distribution functions (PDFs). The HERA-II running program is now underway and is expected to provide a substantial increase in the luminosity collected at HERA. In this contribution, a study is presented which investigates the potential impact of future data from HERA on the proton PDF uncertainties, within the currently planned running scenario. In addition, the effect of a possible future measurement of the longitudinal structure function, F L, on the gluon distribution is investigated. © 2005 American Institute of Physics.

Observation, modeling, and temperature dependence of doubly peaked electric fields in irradiated silicon pixel sensors

ArXiv physics/0510040 (2005)

Authors:

M Swartz, V Chiochia, Y Allkofer, D Bortoletto, L Cremaldi, S Cucciarelli, A Dorokhov, C Hoermann, D Kim, M Konecki, D Kotlinski, K Prokofiev, C Regenfus, T Rohe, DA Sanders, S Son, T Speer

Multijet production in neutral current deep inelastic scattering at HERA and determination of αs

European Physical Journal C 44:2 (2005) 183-193

Authors:

S Chekanov, M Derrick, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, N Pavel, AG Yagües Molina, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, G Cara Romeo, L Cifarelli, F Cindolo, A Contin, M Corradi, S de Pasquale, P Giusti, G Iacobucci, A Margotti, A Montanari, R Nania, F Palmonari, A Pesci, A Polini, L Rinaldi, G Sartorelli, A Zichichi, G Aghuzumtsyan, D Bartsch, I Brock, S Goers, H Hartmann, E Hilger, P Irrgang, HP Jakob, O Kind, U Meyer, E Paul, J Rautenberg, R Renner, KC Voss, M Wang, M Wlasenko, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Capua, A Mastroberardino, M Schioppa, G Susinno, E Tassi, JY Kim, KJ Ma, M Helbich, Y Ning, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, D Szuba, L Zawiejski, L Adamczyk, T Bołd, I Grabowska-Bołd, D Kisielewska, AM Kowal, J Łukasik, M Przybycień, L Suszycki, J Szuba, A Kotański, W Slomiński, V Adler, U Behrens, I Bloch, K Borras, G Drews, J Fourletova, A Geiser, D Gladkov, P Göttlicher, O Gutsche, T Haas, W Hain, C Horn

Abstract:

Multijet production rates in neutral current deep inelastic scattering have been measured in the range of exchanged boson virtualities 10 < Q 2 < 5000 GeV2. The data were taken at the ep collider HERA with centre-of-mass energy √s = 318 GeV using the ZEUS detector and correspond to an integrated luminosity of 82.2pb-1. Jets were identified in the Breit frame using the kT cluster algorithm in the longitudinally invariant inclusive mode. Measurements of differential dijet and trijet cross sections are presented as functions of jet transverse energy (ET,Bjet), pseudorapidity (ηLAB jet) and Q2 with ET,Bjet > 5 GeV and -1 < ηLABjet < 2.5. Next-to-leading-order QCD calculations describe the data well. The value of the strong coupling constant αs(MZ), determined from the ratio of the trijet to dijet cross sections, is αs(MZ) = 0.1179 ± 0.0013 (stat.)-0.0046-0.0028 (exp.) -0.0046+0.0064 (th.). © Springer-Verlag / Società Italiana di Fisica 2005.

Search for supersymmetric Higgs bosons in the di-tau decay mode in pp̄ collisions at s=1.8TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 72:7 (2005)

Authors:

D Acosta, T Affolder, MG Albrow, D Ambrose, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, A Artikov, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Behari, S Belforte, WH Bell, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, A Bocci, A Bodek, G Bolla, A Bolshov, D Bortoletto, J Boudreau, C Bromberg, E Brubaker, J Budagov, HS Budd, K Burkett, G Busetto, KL Byrum, S Cabrera, M Campbell, W Carithers, D Carlsmith, A Castro, D Cauz, A Cerri, L Cerrito, J Chapman, C Chen, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, ML Chu, JY Chung, WH Chung, YS Chung, CI Ciobanu, AG Clark, M Coca, A Connolly, M Convery, J Conway, M Cordelli, J Cranshaw, R Culbertson, D Dagenhart, S D'Auria, P De Barbaro, S De Cecco, S Dell'Agnello, M Dell'Orso, S Demers, L Demortier, M Deninno, D De Pedis, PF Derwent, C Dionisi, JR Dittmann, A Dominguez, S Donati, M D'Onofrio, T Dorigo, N Eddy, R Erbacher, D Errede, S Errede

Abstract:

A search for the direct production of Higgs bosons in the di-tau decay mode is performed with 86.3±3.5pb-1 of data collected with the Collider Detector at Fermilab during the 1994-1995 data taking period of the Tevatron. We search for events where one tau decays to an electron plus neutrinos and the other tau decays hadronically. We perform a counting experiment and set limits on the cross section for supersymmetric Higgs boson production where tan β is large and mA is small. For a benchmark parameter space point where mA0=100GeV/c2 and tan β=50, we limit the production cross section multiplied by the branching ratio to be less than 77.9 pb at the 95% confidence level compared to the theoretically predicted value of 11.0 pb. This is the first search for Higgs bosons decaying to tau pairs at a hadron collider. © 2005 The American Physical Society.

Fluence dependence of charge collection of irradiated pixel sensors

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment Elsevier 552:1-2 (2005) 232-238

Authors:

T Rohe, D Bortoletto, V Chiochia, LM Cremaldi, S Cucciarelli, A Dorokhov, C Hörmann, D Kim, M Konecki, D Kotliński, K Prokofiev, C Regenfus, DA Sanders, S Son, T Speer, M Swartz