Laser-plasma accelerator group

Research group

Research theme

Sub department

About

Observation of isolated high-ET photons in deep inelastic scattering

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 595:1-4 (2004) 86-100

Authors:

S Chekanov, M Derrick, JH Loizides, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, N Pavel, 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, 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, A Stifutkin, J Tandler, KC Voss, M Wang, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Wing, M Capua, A Mastroberardino, M Schioppa, G Susinno, JY Kim, IT Lim, KJ Ma, MY Pac, M Helbich, Y Ning, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, L Zawiejski, L Adamczyk, T Bold, I Grabowska-Bold, D Kisielewska, AM Kowal, M Kowal, J Lukasik, M Przybycien, L Suszycki, D Szuba, J Szuba, A Kotanski, W Slominski, V Adler, U Behrens, I Bloch, K Borras, V Chiochia, D Dannheim, G Drews, J Fourletova, U Fricke, A Geiser

Abstract:

First measurements of cross sections for isolated prompt photon production in deep inelastic ep scattering have been made using the ZEUS detector at the HERA electron-proton collider using an integrated luminosity of 121 pb -1. A signal for isolated photons in the transverse energy and rapidity ranges 535GeV2. Cross sections are presented for inclusive prompt photons and for those accompanied by a single jet in the range ETjet≥6GeV and -1. 5≤ηjet<1.8. Calculations at order α 3αs describe the data reasonably well. © 2004 Elsevier B.V. All rights reserved.
More details from the publisher
More details

Bottom photoproduction measured using decays into muons in dijet events inepcollisions ats=318GeV

Physical Review D American Physical Society (APS) 70:1 (2004) 012008

Authors:

S Chekanov, M Derrick, D Krakauer, JH Loizides, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, 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, G Sartorelli, A Zichichi, G Aghuzumtsyan, D Bartsch, I Brock, S Goers, H Hartmann, E Hilger, P Irrgang, H-P Jakob, O Kind, U Meyer, E Paul, J Rautenberg, R Renner, A Stifutkin, J Tandler, KC Voss, M Wang, A Weber, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Wing, M Capua, A Mastroberardino, M Schioppa, G Susinno, JY Kim, YK Kim, JH Lee, IT Lim, MY Pac, A Caldwell, M Helbich, X Liu, B Mellado, Y Ning, S Paganis, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, L Zawiejski, L Adamczyk, T Bołd, I Grabowska-Bołd, D Kisielewska, AM Kowal, M Kowal, T Kowalski, M Przybycień, L Suszycki, D Szuba, J Szuba, A Kotański, W Słomiński, V Adler, U Behrens, I Bloch, K Borras, V Chiochia, D Dannheim, G Drews, J Fourletova, U Fricke, A Geiser, P Göttlicher, O Gutsche, T Haas, W Hain, S Hillert, B Kahle, U Kötz, H Kowalski, G Kramberger, H Labes, D Lelas, H Lim, B Löhr, R Mankel, I-A Melzer-Pellmann, CN Nguyen, D Notz, AE Nuncio-Quiroz, A Polini, A Raval, L Rurua, U Schneekloth, U Stösslein, G Wolf, C Youngman, W Zeuner, S Schlenstedt, G Barbagli, E Gallo, C Genta, PG Pelfer, A Bamberger, A Benen, F Karstens, D Dobur, NN Vlasov, M Bell, PJ Bussey, AT Doyle, J Ferrando, J Hamilton, S Hanlon, DH Saxon, IO Skillicorn, I Gialas, T Carli, T Gosau, U Holm, N Krumnack, E Lohrmann, M Milite, H Salehi, P Schleper, S Stonjek, K Wichmann, K Wick, A Ziegler, Ar Ziegler, C Collins-Tooth, C Foudas, R Gonçalo, KR Long, AD Tapper, P Cloth, D Filges, M Kataoka, K Nagano, K Tokushuku, S Yamada, Y Yamazaki, AN Barakbaev, EG Boos, NS Pokrovskiy, BO Zhautykov, D Son, K Piotrzkowski, F Barreiro, C Glasman, O González, L Labarga, J del Peso, E Tassi, J Terrón, M Vázquez, M Zambrana, M Barbi, F Corriveau, S Gliga, J Lainesse, S Padhi, DG Stairs, R Walsh, T Tsurugai, A Antonov, P Danilov, BA Dolgoshein, D Gladkov, V Sosnovtsev, S Suchkov, RK Dementiev, PF Ermolov, Yu A Golubkov, II Katkov, LA Khein, IA Korzhavina, VA Kuzmin, BB Levchenko, O Yu Lukina, AS Proskuryakov, LM Shcheglova, SA Zotkin, N Coppola, S Grijpink, E Koffeman, P Kooijman, E Maddox, A Pellegrino, S Schagen, H Tiecke, JJ Velthuis, L Wiggers, E de Wolf, N Brümmer, B Bylsma, LS Durkin, TY Ling, AM Cooper-Sarkar, A Cottrell, RCE Devenish, B Foster, G Grzelak, C Gwenlan, S Patel, PB Straub, R Walczak, A Bertolin, R Brugnera, R Carlin, F Dal Corso, S Dusini, A Garfagnini, S Limentani, A Longhin, A Parenti, M Posocco, L Stanco, M Turcato, EA Heaphy, F Metlica, BY Oh, JJ Whitmore, Y Iga, G D’Agostini, G Marini, A Nigro, C Cormack, JC Hart, NA McCubbin, C Heusch, IH Park, N Pavel, H Abramowicz, A Gabareen, S Kananov, A Kreisel, A Levy, M Kuze, T Fusayasu, S Kagawa, T Kohno, T Tawara, T Yamashita, R Hamatsu, T Hirose, M Inuzuka, H Kaji, S Kitamura, K Matsuzawa, MI Ferrero, V Monaco, R Sacchi, A Solano, M Arneodo, M Ruspa, T Koop, JF Martin, A Mirea, JM Butterworth, R Hall-Wilton, TW Jones, MS Lightwood, MR Sutton, C Targett-Adams, J Ciborowski, R Ciesielski, P Łużniak, RJ Nowak, JM Pawlak, J Sztuk, T Tymieniecka, A Ukleja, J Ukleja, AF Zarnecki, M Adamus, P Plucinski, Y Eisenberg, LK Gladilin, D Hochman, U Karshon, M Riveline, D Kçira, S Lammers, L Li, DD Reeder, M Rosin, AA Savin, WH Smith, A Deshpande, S Dhawan, S Bhadra, CD Catterall, S Fourletov, G Hartner, S Menary, M Soares, J Standage
More details from the publisher

Evidence for a narrow baryonic state decaying to KS0p and KS0p̄ in deep inelastic scattering at HERA

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 591:1-2 (2004) 7-22

Authors:

S Chekanov, M Derrick, JH Loizides, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, N Pavel, 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, 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, A Stifutkin, J Tandler, KC Voss, M Wang, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Wing, M Capua, A Mastroberardino, M Schioppa, G Susinno, JY Kim, IT Lim, KJ Ma, MY Pac, M Helbich, Y Ning, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, L Zawiejski, L Adamczyk, T Bold, I Grabowska-Bold, D Kisielewska, AM Kowal, M Kowal, J Łukasik, M Przybycień, L Suszycki, D Szuba, J Szuba, A Kotański, W Slomiński, V Adler, U Behrens, I Bloch, K Borras, V Chiochia, D Dannheim, G Drews, J Fourletova, U Fricke, A Geiser

Abstract:

A resonance search has been made in the K0Sp and K0Sp̄ invariant-mass spectrum measured with the ZEUS detector at HERA using an integrated luminosity of 121 pb-1. The search was performed in the central rapidity region of inclusive deep inelastic scattering at an ep centre-of-mass energy of 300-318 GeV for exchanged photon virtuality, Q2, above 1 GeV2. Recent results from fixed-target experiments give evidence for a narrow baryon resonance decaying to K+n and K0Sp, interpreted as a pentaquark. The results presented here support the existence of such state, with a mass of 1521.5±1.5(stat.)+2.8-1.7(syst.) MeV and a Gaussian width consistent with the experimental resolution of 2 MeV. The signal is visible at high Q2 and, for Q2>20 GeV2, contains 221±48 events. The probability of a similar signal anywhere in the range 1500-1560 MeV arising from fluctuations of the background is below 6×10-5. © 2004 Elsevier B.V. All rights reserved.
More details from the publisher
More details

Search for contact interactions, large extra dimensions and finite quark radius in ep collisions at HERA

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 591:1-2 (2004) 23-41

Authors:

S Chekanov, M Derrick, D Krakauer, JH Loizides, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, 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, 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, A Stifutkin, J Tandler, KC Voss, M Wang, A Weber, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Wing, M Capua, A Mastroberardino, M Schioppa, G Susinno, JY Kim, YK Kim, JH Lee, IT Lim, MY Pac, A Caldwell, M Helbich, X Liu, B Mellado, Y Ning, S Paganis, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, L Zawiejski, L Adamczyk, T Bold, I Grabowska-Bold, D Kisielewska, AM Kowal, M Kowal, T Kowalski, M Przybycien, L Suszycki, D Szuba, J Szuba, A Kotański, W Slomiński, V Adler, U Behrens, I Bloch, K Borras, V Chiochia

Abstract:

A search for physics beyond the Standard Model has been performed with high-Q2 neutral current deep inelastic scattering events recorded with the ZEUS detector at HERA. Two data sets, e+p→e +X and e-p→e-X, with respective integrated luminosities of 112 pb-1 and 16 pb-1, were analyzed. The data reach Q2 values as high as 40000 GeV2. No significant deviations from Standard Model predictions were observed. Limits were derived on the effective mass scale in eeqq contact interactions, the ratio of leptoquark mass to the Yukawa coupling for heavy leptoquark models and the mass scale parameter in models with large extra dimensions. The limit on the quark charge radius, in the classical form factor approximation, is 0.85×10 -16 cm. © 2004 Published by Elsevier B.V.
More details from the publisher
More details

Photoproduction of D*± mesons associated with a leading neutron

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 590:3-4 (2004) 143-160

Authors:

S Chekanov, M Derrick, D Krakauer, JH Loizides, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, 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, 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, A Stifutkin, J Tandler, KC Voss, M Wang, A Weber, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Wing, M Capua, A Mastroberardino, M Schioppa, G Susinno, JY Kim, YK Kim, JH Lee, IT Lim, MY Pac, A Caldwell, M Helbich, X Liu, B Mellado, Y Ning, S Paganis, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, L Zawiejski, L Adamczyk, T Bold, I Grabowska-Bold, D Kisielewska, AM Kowal, M Kowal, T Kowalski, M Przybycień, L Suszycki, D Szuba, J Szuba, A Kotański, W Slomiński, V Adler, U Behrens, I Bloch, K Borras, V Chiochia

Abstract:

The photoproduction of D*±(2010) mesons associated with a leading neutron has been observed with the ZEUS detector in ep collisions at HERA using an integrated luminosity of 80 pb-1. The neutron carries a large fraction, xL>0.2, of the incoming proton beam energy and is detected at very small production angles, θn< 0.8 mrad, an indication of peripheral scattering. The D* meson is centrally produced with pseudorapidity η<1.5, and has a transverse momentum pT>1.9 GeV, which is large compared to the average transverse momentum of the neutron of 0.22 GeV. The ratio of neutron-tagged to inclusive D* production is 8.85±0.93(stat.) +0.48-0.61(syst.)% in the photon-proton center-of-mass energy range 130
More details from the publisher
More details