Prof Roman Walczak: Publications

Inclusive-jet photoproduction at HERA and determination of alphas

(2012)

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, N Bartosik, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, V Bokhonov, T Bold, K Bondarenko, EG Boos, K Borras, D Boscherini, D Bot, I Brock, E Brownson, R Brugnera, N Brummer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, 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 del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, G Dolinska, 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, G Gach, A Galas, E Gallo, A Garfagnini, A Geiser, I Gialas, A Gizhko, LK Gladilin, D Gladkov, C Glasman, O Gogota, Yu A Golubkov, P Gottlicher, I Grabowska-Bold, J Grebenyuk, I Gregor, G Grigorescu, G Grzelak, O Gueta, M Guzik, C Gwenlan, T Haas, W Hain, R Hamatsu, JC Hart, H Hartmann, G Hartner, E Hilger, D Hochman, R Hori, K Horton, A Huttmann, ZA Ibrahim, Y Iga, R Ingbir, M Ishitsuka, H-P Jakob, F Januschek, TW Jones, M Jungst, I Kadenko, B Kahle, 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, N Kondrashova, O Kononeko, P Kooijman, Ie Korol, IA Korzhavina, A Kotanski, U Kotz, H Kowalski, O Kuprash, M Kuze, A Lee, BB Levchenko, A Levy, V Libov, S Limentani, TY Ling, M Lisovyi, E Lobodzinska, W Lohmann, B Lohr, E Lohrmann, KR Long, A Longhin, D Lontkovskyi, O Yu Lukina, J Maeda, S Magill, I Makarenko, J Malka, R Mankel, A Margotti, G Marini, JF Martin, A Mastroberardino, MCK Mattingly, I-A Melzer-Pellmann, S Mergelmeyer, S Miglioranzi, F Mohamad Idris, V Monaco, A Montanari, JD Morris, K Mujkic, B Musgrave, K Nagano, T Namsoo, R Nania, A Nigro, Y Ning, T Nobe, U Noor, D Notz, RJ Nowak, AE Nuncio-Quiroz, BY Oh, N Okazaki, K Oliver, K Olkiewicz, Yu Onishchuk, 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, I Rubinsky, M Ruspa, R Sacchi, U Samson, G Sartorelli, AA Savin, DH Saxon, M Schioppa, S Schlenstedt, P Schleper, WB Schmidke, U Schneekloth, V Schonberg, T Schorner-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, N Stefaniuk, A Stern, TP Stewart, A Stifutkin, P Stopa, S Suchkov, G Susinno, L Suszycki, J Sztuk-Dambietz, D Szuba, J Szuba, AD Tapper, E Tassi, J Terron, T Theedt, H Tiecke, K Tokushuku, J Tomaszewska, V Trusov, T Tsurugai, M Turcato, O Turkot, T Tymieniecka, M Vazquez, A Verbytskyi, O Viazlo, NN Vlasov, R Walczak, WAT Wan Abdullah, JJ Whitmore, L Wiggers, M Wing, M Wlasenko, G Wolf, H Wolfe, K Wrona, AG Yagues-Molina, S Yamada, Y Yamazaki, R Yoshida, C Youngman, O Zabiegalov, AF Zarnecki, L Zawiejski, O Zenaiev, W Zeuner, BO Zhautykov, N Zhmak, C Zhou, A Zichichi, Z Zolkapli, DS Zotkin

Details from ArXiV

More details from the publisher

Scaled momentum distributions for K S⁰ and ∧/∧ in DIS at HERA

Journal of High Energy Physics 2012:3 (2012)

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, N Bartosik, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, V Bokhonov, T Bold, K Bondarenko, EG Boos, K Borras, D Boscherini, D Bot, I Brock, E Brownson, R Brugnera, N Brümmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, 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 Del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, G Dolinska, 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, G Gach, A Galas, E Gallo, A Garfagnini, A Geiser, I Gialas, LK Gladilin, D Gladkov, C Glasman, O Gogota, YA Golubkov, P Göttlicher, I Grabowska-Bo, J Grebenyuk, I Gregor, G Grigorescu

Abstract:

Scaled momentum distributions for the strange hadrons K S0 and ∧/∧were measured in deep inelastic ep scattering with the ZEUS detector at HERA using an integrated luminosity of 330 pb -1. The evolution of these distributions with the photon virtuality, Q 2, was studied in the kinematic region 10 < Q 2 < 40000 GeV 2 and 0.001 < x < 0.75, where x is the Bjorken scaling variable. Clear scaling violations are observed. Predictions based on different approaches to fragmentation were compared to the measurements. Leading-logarithm parton-shower Monte Carlo calculations interfaced to the Lund string fragmentation model describe the data reasonably well in the whole range measured. Nextto-leading-order QCD calculations based on fragmentation functions, FFs, extracted from e +e - data alone, fail to describe the measurements. The calculations based on FFs extracted from a global analysis including e +e -, ep and pp data give an improved description. The measurements presented in this paper have the potential to further constrain the FFs of quarks, anti-quarks and gluons yielding K S0 and ∧/∧ strange hadrons. © SISSA 2012.

More details from the publisher

Angular correlations in three-jet events in ep collisions at HERA

Physical Review D - Particles, Fields, Gravitation and Cosmology 85:5 (2012)

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, N Bartosik, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, V Bokhonov, T Bołd, K Bondarenko, EG Boos, K Borras, D Boscherini, D Bot, I Brock, E Brownson, R Brugnera, N Brümmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, 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 Del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, G Dolinska, 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, G Gach, A Galas, E Gallo, A Garfagnini, A Geiser, I Gialas, LK Gladilin, D Gladkov, C Glasman, O Gogota, YA Golubkov, P Göttlicher, I Grabowska-Bołd, J Grebenyuk, I Gregor, G Grigorescu

Abstract:

Three-jet production in deep inelastic ep scattering and photoproduction was investigated with the ZEUS detector at HERA using an integrated luminosity of up to 127pb-1. Measurements of differential cross sections are presented as functions of angular correlations between the three jets in the final state and the proton-beam direction. These correlations provide a stringent test of perturbative QCD and show sensitivity to the contributions from different color configurations. Fixed-order perturbative calculations assuming the values of the color factors CF, CA, and TF as derived from a variety of gauge groups were compared to the measurements to study the underlying gauge group symmetry. The measured angular correlations in the deep inelastic ep scattering and photoproduction regimes are consistent with the admixture of color configurations as predicted by SU(3) and disfavour other symmetry groups, such as SU(N) in the limit of large N. © 2012 American Physical Society.

More details from the publisher

More details

Measurement of the t dependence in exclusive photoproduction of Υ{hooked} (1S) mesons at HERA

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 708:1-2 (2012) 14-20

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, N Bartosik, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, V Bokhonov, T Bołd, K Bondarenko, EG Boos, K Borras, D Boscherini, D Bot, I Brock, E Brownson, R Brugnera, N Brümmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, 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 del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, G Dolinska, 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, 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, G Grigorescu

Abstract:

The exclusive photoproduction reaction γp→Υ{hooked} (1S)p has been studied with the ZEUS detector in ep collisions at HERA using an integrated luminosity of 468 pb -1. The measurement covers the kinematic range 60

More details from the publisher

More details

Search for single-top production in ep collisions at HERA

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 708:1-2 (2012) 27-36

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, N Bartosik, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, V Bokhonov, T Bołd, K Bondarenko, EG Boos, K Borras, D Boscherini, D Bot, I Brock, E Brownson, R Brugnera, N Brümmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, 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 del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, G Dolinska, 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, 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, G Grigorescu

Abstract:

A search for single-top production, ep→etX, has been performed with the ZEUS detector at HERA using data corresponding to an integrated luminosity of 0.37 fb -1. No evidence for top production was found, consistent with the expectation from the Standard Model. Limits were computed for single-top production via flavour changing neutral current transitions involving a neutral electroweak vector boson, γ or Z. The result was combined with a previous ZEUS result yielding a total luminosity of 0.50 fb -1. A 95% credibility level upper limit of 0.13 pb was obtained for the cross section at the centre-of-mass energy of √s=315 GeV. © 2012 Elsevier B.V.

More details from the publisher

Prof Roman Walczak

Research theme

Sub department

Inclusive-jet photoproduction at HERA and determination of alphas

Authors:

Scaled momentum distributions for K S⁰ and ∧/∧ in DIS at HERA

Authors:

Abstract:

Angular correlations in three-jet events in ep collisions at HERA

Authors:

Abstract:

Measurement of the t dependence in exclusive photoproduction of Υ{hooked} (1S) mesons at HERA

Authors:

Abstract:

Search for single-top production in ep collisions at HERA

Authors:

Abstract:

FIND US

CONTACT US

Prof Roman Walczak

Research theme

Sub department

Research groups

Inclusive-jet photoproduction at HERA and determination of alphas

Authors:

Scaled momentum distributions for K S0 and ∧/∧ in DIS at HERA

Authors:

Abstract:

Angular correlations in three-jet events in ep collisions at HERA

Authors:

Abstract:

Measurement of the t dependence in exclusive photoproduction of Υ{hooked} (1S) mesons at HERA

Authors:

Abstract:

Search for single-top production in ep collisions at HERA

Authors:

Abstract:

Scaled momentum distributions for K S⁰ and ∧/∧ in DIS at HERA