Combined measurement and QCD analysis of the inclusive e ±p scattering cross sections at HERA

Journal of High Energy Physics 2010:1 (2010)

Authors:

FD Aaron, H Abramowicz, I Abt, L Adamczyk, M Adamus, M Al-Daya Martin, C Alexa, V Andreev, S Antonelli, P Antonioli, A Antonov, B Antunovic, M Arneodo, V Aushev, O Bachynska, S Backovic, A Baghdasaryan, A Bamberger, AN Barakbaev, G Barbagli, G Bari, F Barreiro, E Barrelet, W Bartel, D Bartsch, M Basile, K Begzsuren, O Behnke, J Behr, U Behrens, L Bellagamba, A Belousov, A Bertolin, S Bhadra, M Bindi, JC Bizot, C Blohm, T Bold, EG Boos, M Borodin, K Borras, D Boscherini, D Bot, V Boudry, SK Boutle, I Bozovic-Jelisavcic, J Bracinik, G Brandt, M Brinkmann, V Brisson, I Brock, E Brownson, R Brugnera, N Brümmer, D Bruncko, A Bruni, G Bruni, B Brzozowska, A Bunyatyan, G Buschhorn, PJ Bussey, JM Butterworth, B Bylsma, L Bystritskaya, A Caldwell, AJ Campbell, KBC Avila, M Capua, R Carlin, CD Catterall, K Cerny, V Cerny, S Chekanov, V Chekelian, A Cholewa, J Chwastowski, J Ciborowski, R Ciesielski, L Cifarelli, F Cindolo, A Contin, JG Contreras, AM Cooper-Sarkar, N Coppola, M Corradi, F Corriveau, M Costa, JA Coughlan, G Cozzika, J Cvach, G D'Agostini, JB Dainton, F Dal Corso, K Daum, M Deak, J De Favereau, B Delcourt, J Del Peso, J Delvax, RK Dementiev

Abstract:

A combination is presented of the inclusive deep inelastic cross sections measured by the H1 and ZEUS Collaborations in neutral and charged current unpolarised e±p scattering at HERA during the period 1994-2000. The data span six orders of magnitude in negative four-momentum-transfer squared, Q2, and in Bjorken x. The combination method used takes the correlations of systematic uncertainties into account, resulting in an improved accuracy. The combined data are the sole input in a NLO QCD analysis which determines a new set of parton distributions, HERAPDF1.0, with small experimental uncertainties. This set includes an estimate of the model and parametrisation uncertainties of the fit result.

Inclusive-jet cross sections in NC DIS at HERA and a comparison of the kT, anti-kT and SIScone jet algorithms

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 691:3 (2010) 127-137

Authors:

H Abramowicz, I Abt, L Adamczyk, M Adamus, R Aggarwal, S Antonelli, P Antonioli, A Antonov, M Arneodo, V Aushev, Y Aushev, O Bachynska, A Bamberger, AN Barakbaev, G Barbagli, G Bari, F Barreiro, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, T Bołd, EG Boos, M Borodin, K Borras, D Boscherini, D Bot, SK Boutle, I Brock, E Brownson, R Brugnera, N Brümmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, JM Butterworth, B Bylsma, A Caldwell, M Capua, R Carlin, CD Catterall, S Chekanov, J Chwastowski, J Ciborowski, R Ciesielski, L Cifarelli, F Cindolo, A Contin, AM Cooper-Sarkar, N Coppola, M Corradi, F Corriveau, M Costa, G D'Agostini, FD Corso, J de Favereau, J de Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, AT Doyle, V Drugakov, LS Durkin, S Dusini, Y Eisenberg, PF Ermolov, A Eskreys, S Fang, S Fazio, J Ferrando, MI Ferrero, J Figiel, M Forrest, B Foster, S Fourletov, G Gach, A Galas, E Gallo, A Garfagnini, A Geiser, I Gialas, LK Gladilin, D Gladkov, C Glasman, O Gogota, Y Golubkov, P Göttlicher, I Grabowska-Bołd, J Grebenyuk, I Gregor

Abstract:

For the first time, differential inclusive-jet cross sections have been measured in neutral current deep inelastic ep scattering using the anti-kT and SIScone algorithms. The measurements were made for boson virtualities Q2>125 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 82 pb-1 and the jets were identified in the Breit frame. The performance and suitability of the jet algorithms for their use in hadron-like reactions were investigated by comparing the measurements to those performed with the kT algorithm. Next-to-leading-order QCD calculations give a good description of the measurements. Measurements of the ratios of cross sections using different jet algorithms are also presented; the measured ratios are well described by calculations including up to O(αs3) terms. Values of αs(MZ) were extracted from the data; the results are compatible with and have similar precision to the value extracted from the kT analysis. © 2010 Elsevier B.V.

A QCD analysis of ZEUS diffractive data

Nuclear Physics B 831:1-2 (2010) 1-25

Authors:

S Chekanov, M Derrick, S Magill, B Musgrave, D Nicholass, J Repond, R Yoshida, MCK Mattingly, P Antonioli, G Bari, L Bellagamba, D Boscherini, A Bruni, G Bruni, F Cindolo, M Corradi, G Iacobucci, A Margotti, R Nania, A Polini, S Antonelli, M Basile, M Bindi, L Cifarelli, A Contin, S De Pasquale, G Sartorelli, A Zichichi, D Bartsch, I Brock, H Hartmann, E Hilger, HP Jakob, M Jüngst, AE Nuncio-Quiroz, E Paul, U Samson, V Schönberg, R Shehzadi, M Wlasenko, JD Morris, M Kaur, P Kaur, I Singh, M Capua, S Fazio, A Mastroberardino, M Schioppa, G Susinno, E Tassi, JY Kim, ZA Ibrahim, FM Idris, B Kamaluddin, WAT Wan Abdullah, Y Ning, Z Ren, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, B Pawlik, P Stopa, L Zawiejski, L Adamczyk, T Bołd, I Grabowska-Bołd, D Kisielewska, J Łukasik, M Przybycień, L Suszycki, A Kotański, W Słomiński, O Bachynska, O Behnke, J Behr, U Behrens, C Blohm, K Borras, D Bot, R Ciesielski, N Coppola, S Fang, A Geiser, P Göttlicher, J Grebenyuk, I Gregor, T Haas, W Hain, A Hüttmann, F Januschek, B Kahle, II Katkov, U Klein, U Kötz, H Kowalski, V Libov, M Lisovyi

Abstract:

ZEUS inclusive diffractive-cross-section measurements have been used in a DGLAP next-to-leading-order QCD analysis to extract the diffractive parton distribution functions. Data on diffractive dijet production in deep inelastic scattering have also been included to constrain the gluon density. Predictions based on the extracted parton densities are compared to diffractive charm and dijet photoproduction data. © 2010 Elsevier B.V.

Measurement of beauty production in DIS and F_2^bbbar extraction at ZEUS

(2010)

Authors:

ZEUS collaboration, H Abramowicz, I Abt, L Adamczyk, M Adamus, R Aggarwal, S Antonelli, P Antonioli, A Antonov, M Arneodo, V Aushev, Y Aushev, O Bachynska, A Bamberger, AN Barakbaev, G Barbagli, G Bari, F Barreiro, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, T Bold, EG Boos, M Borodin, K Borras, D Boscherini, D Bot, SK Boutle, I Brock, E Brownson, R Brugnera, N Bruemmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, JM Butterworth, B Bylsma, A Caldwell, M Capua, R Carlin, CD Catterall, S Chekanov, J Chwastowski, J Ciborowski, R Ciesielski, L Cifarelli, F Cindolo, A Contin, AM Cooper-Sarkar, N Coppola, M Corradi, F Corriveau, M Costa, G D'Agostini, F Dal Corso, J de Favereau, J del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, AT Doyle, V Drugakov, LS Durkin, S Dusini, Y Eisenberg, PF Ermolov, A Eskreys, S Fang, S Fazio, J Ferrando, MI Ferrero, J Figiel, M Forrest, B Foster, S Fourletov, G Gach, A Galas, E Gallo, A Garfagnini, A Geiser, I Gialas, LK Gladilin, D Gladkov, C Glasman, O Gogota, Yu A Golubkov, P Goettlicher, I Grabowska-Bold, J Grebenyuk, I Gregor, G Grigorescu, G Grzelak, C Gwenlan, T Haas, W Hain, R Hamatsu, JC Hart, H Hartmann, G Hartner, E Hilger, D Hochman, U Holm, R Hori, K Horton, A Huettmann, G Iacobucci, ZA Ibrahim, Y Iga, R Ingbir, M Ishitsuka, H-P Jakob, F Januschek, M Jimenez, TW Jones, M Juengst, I Kadenko, B Kahle, B Kamaluddin, S Kananov, T Kanno, U Karshon, F Karstens, II Katkov, M Kaur, P Kaur, A Keramidas, LA Khein, JY Kim, D Kisielewska, S Kitamura, R Klanner, U Klein, E Koffeman, D Kollar, P Kooijman, Ie Korol, IA Korzhavina, A Kotanski, U Koetz, H Kowalski, P Kulinski, O Kuprash, M Kuze, VA Kuzmin, A Lee, BB Levchenko, A Levy, V Libov, S Limentani, TY Ling, M Lisovyi, E Lobodzinska, W Lohmann, B Loehr, E Lohrmann, JH Loizides, KR Long, A Longhin, D Lontkovskyi, O Yu Lukina, P Luzniak, J Maeda, S Magill, I Makarenko, J Malka, R Mankel, A Margotti, G Marini, JF Martin, A Mastroberardino, T Matsumoto, MCK Mattingly, I-A Melzer-Pellmann, S Miglioranzi, F Mohamad Idris, V Monaco, A Montanari, JD Morris, B Musgrave, K Nagano, T Namsoo, R Nania, D Nicholass, A Nigro, Y Ning, U Noor, D Notz, RJ Nowak, AE Nuncio-Quiroz, BY Oh, N Okazaki, K Oliver, K Olkiewicz, Yu Onishchuk, O Ota, K Papageorgiu, A Parenti, E Paul, JM Pawlak, B Pawlik, PG Pelfer, A Pellegrino, W Perlanski, H Perrey, K Piotrzkowski, P Plucinski, NS Pokrovskiy, A Polini, AS Proskuryakov, M Przybycien, A Raval, DD Reeder, B Reisert, Z Ren, J Repond, YD Ri, A Robertson, P Roloff, E Ron, I Rubinsky, M Ruspa, R Sacchi, A Salii, U Samson, G Sartorelli, AA Savin, DH Saxon, M Schioppa, S Schlenstedt, P Schleper, WB Schmidke, U Schneekloth, V Schoenberg, T Schoerner-Sadenius, J Schwartz, F Sciulli, LM Shcheglova, R Shehzadi, S Shimizu, I Singh, IO Skillicorn, W Slominski, WH Smith, V Sola, A Solano, D Son, V Sosnovtsev, A Spiridonov, H Stadie, L Stanco, A Stern, TP Stewart, A Stifutkin, P Stopa, S Suchkov, G Susinno, L Suszycki, J Sztuk, D Szuba, J Szuba, AD Tapper, E Tassi, J Terron, T Theedt, H Tiecke, K Tokushuku, O Tomalak, J Tomaszewska, T Tsurugai, M Turcato, T Tymieniecka, C Uribe-Estrada, M Vazquez, A Verbytskyi, V Viazlo, NN Vlasov, O Volynets, R Walczak, WAT Wan Abdullah, JJ Whitmore, J Whyte, L Wiggers, M Wing, M Wlasenko, G Wolf, H Wolfe, K Wrona, AG Yagues-Molina, S Yamada, Y Yamazaki, R Yoshida, C Youngman, AF Zarnecki, L Zawiejski, O Zenaiev, W Zeuner, BO Zhautykov, N Zhmak, C Zhou, A Zichichi, M Zolko, DS Zotkin, Z Zulkapli

Investigation of the role of plasma channels as waveguides for laser-wakefield accelerators

New Journal of Physics 12 (2010)

Authors:

TPA Ibbotson, N Bourgeois, TP Rowlands-Rees, LS Caballero, SI Bajlekov, PA Walker, S Kneip, M Spd, SR Nagel, P Caj, N Delerue, G Doucas, D Urner, O Chekhlov, RJ Clarke, E Divall, K Ertel, P Foster, SJ Hawkes, CJ Hooker, B Parry, PP Rajeev, MJV Streeter, SM Hooker

Abstract:

The role of plasma channels as waveguides for laser-wakefield accelerators is discussed in terms of the results of experiments performed with the Astra-Gemini laser, numerical simulations using the code WAKE, and the theory of self-focusing and self-guiding of intense laser beams. It is found that at a given electron density, electron beams can be accelerated using lower laser powers in a waveguide structure than in a gas-jet or cell. The transition between relativistically self-guided and channel-assisted guiding is seen in the simulations and in the behaviour of the production of electron beams. We also show that by improving the quality of the driving laser beam the threshold laser energy required to produce electron beams can be reduced by a factor of almost 2. The use of an aperture allows the production of a quasi-monoenergetic electron beam of energy 520 MeV with an input laser power of only 30 TW. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.