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7.8 ZEUS Experiment by P.Plucifiski PLO201875

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7.8 ZEUS Experiment by P.Plucifiski PLO201875 DEPARTMENT OF COSMIC RAY PHYSICS 121 7.8 ZEUS Experiment by P.Plucifiski PLO201875 The Hadron-Electron-Ring-Accelerator (HERA) component of the Zeus detector) was implemented to allows for collisions between electrons of energy 27.5 determine tracks of muons passing through the GeV and protons of energy (after upgrade) 920 GeV. detector and to measure the energies of particles the The Zeus detector is built in the south hall of which are not absorbed in uranium calorimeter. HERA. Its dimensions are 12xl)Oxl9m. The The main subject of our work in DESY is the experiment is focused on studying the structure of trigger system of the BAC calorimeter. Mainly, we are protons. The BAcking Calorimeter (BAC as preparing codes (in Occam) for trigger electronics. 7.9 The Underground Muon Telescope by JGawin, J.Karczmarczyk, .J.Swarzyhski, B.Szabelska, J.Szabelski, P.Tokarski and T.Wibig = D _ - The underground muon telescope of 0.5 m2 area can be correlated with the Forbush decreases of low = - 0 has registered the flux of muons with energies above 5 energy cosmic rays registered in the neutron monitors. cj GeV almost permanently in the year 2001. These From the comparison of our results with other muons are produced in the Earth's atmosphere by measurements of primary cosmic ray decreases it primary cosmic rays that are modulated by solar comes out that some geomagnetic disturbances can phenomena. We performed simulations of muon modulate the flux of primary cosmic ray particles with production in the atmosphere and determined the energies above 50 GeV. We have also started distribution of energy of primary cosmic rays registrations of the muon count rate in the on-surface responsible for muons registered in our telescope. detectors of the air shower array. These measurements These energies are in the range from 10 to 50000 GeV will be included to the analysis of the disturbed energy (median energy around 120 GeV). We have also spectrum of primary cosmic rays. determined the so-called barometric coefficient, which We are working on the project of a large is equal to - 0.0006/mb. underground muon telescope of 40 m2 area, in which The Sun is now in the state of maximum activity. the main detecting elements will be the scintillator It was very active last year and the resulting strips used in the MINOS experiment and multipixel geomagnetic disturbances had various amplitudes. We photo-multipliers. have registered a few decreases of the muon flux that Forbush Decrease registration < 1 - 5 GeV muons. 0.96 0.984 ground level muons 0.92 _ 0.9 neutron monitor Apatity 0.88 .. 29 Oct 31 Oct 02Nov 04 Nov 06 Nov 08 Nov 10 Nov Fig. 1 Example of cosmic ray intensity variation. Forbush Decrease of the 6"' November 2001 registered as: - 9% change in neutron flux in the Apatity Neutron Monitor (www.kolasc.net.ru/cosmicRay/) (corresponding CR energy about 2 GCV) - 3.5 % change in tie Coonltin1g rate of Lodd air shower array surface scintillation detectors (primary CR energy 10 - 50 GeV), - about 2% decrease of 5 GcV muon rate registered in the underground muon telescope (primary CR energy 20-100GeV). 122 Annual Report 2001 LIST OF PUBLICATIONS ELECTRON, MUON. AND HADRON LATERAL DISTRIBUTIONS MEASURED IN AIR SHOWERS BY THE KASCADE EXPERIMENT. T.Antoni,..., J.Zabierowski, et al. (KASCADE Coil.) Astropart. Physics 14 (2001) 245-260 TIME STRUCTURE OF THE EXTENSIVE AIR SHOWER MUON COMPONENT MEASURED BY THE KASCADE EXPERIMENT T.Antoni--..., J.Zabierowski, et al. (KASCADE Col].) Astropart. Physics 15 (2001) 149-165 HIGH ENERGY COSMIC RAYS IN THE LOW STRATOSPHERE AND EXTRAPOLATION ABOVE LHC ENERGIES J.N.Capdevielle, F.Cohen, I.Kurp, C.Lc Gall. B.Szabelska, ..Szabelski 11 Nuovo Cimento C 024C, issue 0405 (2001) 531-538 COSMIC RAY PHYSICS AROUND THE KNEE WITH KASCADE EXPERIMENT A.Haungs-.--- J.Zabierowski, et al. (KASCADE Coil.) IL Nuovo Cintento C 024C, issue 0405 (2001) 599-606 LATERAL DISTRIBUTIONS, LOCALISATION METHODS, (600), SIZE AND ENERGY DETERMINATION IN GIA'IT EAS J.N.Capdevielle, C.Le Gall, J.Gawin, I.Kurp, M.Matraszck, B.Szabelska, J.Szabelski and T.Wibig Nuclear Physics B (Proc. Suppl.) 97(2001) 223-226 RECENT RESULTS OF KASCADE - PHENOMENOLOGY OF EXTENSIVE AIR SHOWERS G.Schatz._ J.Zabicrowski, et al. (KASCADE Coil.) Nucl.Phys.B (Proc.Sup1pl) 97(2001) 93-96 TOWARDS ENERGY SPECTRUM AND COMPOSITION OF PRIMARY COSMIC RAYS IN THE KNEE REGION: METHODS AND RESULTS AT KASCADE A.Haungs, ..., J.Zabicrowski, et al. (KASCADE Coil.) Nucl.Pi..YB (Proc.Suppl/) 97 (2001) 97-100 TEST AND ANALYSIS OF HADRONIC INTERACTION MODELS WITH KASCADE EVENT RATES M.Risse, ..., J.Zabicrowski, et al. (KASCADE Coll.) Nucl.Ph~vs.B (Pioc.Soppl) 97 (2001) 101-104 CROSS SECTION OF THE pp--> pp pizero REACTION BETWEEN 310 AND 425 MeV R.Bilger, ..., J.Stepaniak, J.Zabierowski, et al. Nucl.Pkvs.A 693 (2001) 633- 662 SPECTATOR TAGGING IN QUASI-FREE PROTON-NEUTRON INTERACTIONS IN DEUTERIUM USING AN INTE ZNAL CLUSTER-JET TARGET IN A STORAGE RING R.Bilger,.-..,-A.Kupge, I'.Marciniewski, J.Stepaniak, J.Zabierowski, et al. Nucl. Iustr. and Met/i. A 457 (2001) 64-74 STUDY OF THE EFFECTIVE TRANSVERSE MOMENTUM OF PARTONS IN THE PROTON USING PROMPT PHO'ONS IN PHOTOPRODUCTION AT HERA S.Chekanov, ..., P.Plucifiski, et al. (ZEUS Collaboration) Physics Letters B 51/ (2001) /9-32 MULTIPLICITY MOMENTS IN DEEP INELASTIC SCATTERING AT HERA S.Chekanov, ..., P.Pluciiski, et al. (ZEUS Collaboration) Physics Letters B 510 (2001) 36-54 THREE-JET PRODUCTION IN DIFFRACTIVE DEEP INELASTIC SCATTERING AT HERA S.Chekanov, ..., P.Plucifiski, et al. (ZEUS Collaboration) Phlv sic s Letters B 516 (2001) 273-292 MEASUREMENT OF THE NEUTRAL CURRENT CROSS SECTION AND F 2 STRUCTURE FUNCTION FOR DEEP INELASTIC EP SCATTERING AT HERA S.Chekanov-..., P.Plucinski, et al. (ZEUS Collaboration) The European Physical Journal C 21 (2001) 443-471 NABLYUDENIE SIGNALOV, ZAPAZDYWAYUSZCZIH NA 500-2000 ,us OTNOSITELNO FRONTA SzAL. J.Gawin, S.Pachala, W.W.Poddubny, J.Swarzvinski, B.Szabelska, J.Szabelski, T.Wibig, A.F.Yanin kziviestia RosxjskiejAkadenfii Nauk. Serija Fizicheskaja 65 (2001) 1194-1195 PROSPECTS FOR EXTRAGALACTIC PARTICLES FROM EXOTIC PROCESSES T.Wihig and A. W.Wolfendale J. Phys. C 27 (2001) 1625 DEPARTMENT OF COSMIC RAY PHYSICS 123 HIGH ENERGY INTERACTIONS AROUND THE KNEE T.Wibig J. Phys. G 27(2001) 1633 TEST OF HADRONIC INTERACTION MODELS IN THE FORWARD REGION WITH KASCADE EVENT RATES T.Antoni,..., J.Zabicrowski, et al. (KASCADE Coll.) J. Phys. G. Nucl.Part.Plhv.s. 27 (2001) /785 -1798 A UNIVERSAL ORIGIN FOR COSMIC RAYS ABOVE 107 GEV? A.D.Erlykin, T.Wibig and A.W.Woltendale New Journal of Phys.vics 3 (2001)18.1 PIATA SILA ,,ARS LONGA, VITA BREVIS" T.Wihig, Acta Uni. Lodc., Folia Physica 24 (2001) 3 COSMIC RAYS OF THE HIGHEST ENERGIES: THE CASE FOR EXTRAGALACTIC HEAVY NUCLEI J.Szabelski, T.Wibig and A.W. Wollendale Astroparticle Pli'sics.(in press) FRONT-END READOUT BOARDS FOR STREAMER TUBE MUON TRACKING DETECTOR IN THE KASCADE EAS EXPER IMENT J.Zabicrowski and P.Doll Nuel. Instr. and Meth A. (in pre vs) DIUET PRODUCTION IN NEUTRAL CURRENT DEEP INELASTIC SCATTERING AT HERA S.Chekanov, .-- P.Plucifiski, et al. (ZEUS Collaboration) The Eu ropeasn Physical Journmal (ill piess) PROPERTIES OF HADRONIC FINAL STATES IN DIFFRACTIVE DEEP INELASTIC SCATTERING AT HERA S.Chekanov,..., P.Pluciiiski, et al. (ZEUS Collaboration) Phys. Rev. D (in press) REPORTS ESTIMATION OF THE TRIGGER DISTRIBUTION DELAYS IN THE KASCADE- GRANDE EXPERIMENT J .Zabicrowski Forscelinotgszeiitrumi Karil.vsuhle. Interner Beric/it KASCADE-2/2001-02 51.02.03 PARTICIPATION IN CONFERENCE AND WORKSHOPS invited talks THE CELSIUS-WASA DETECTOR FACILITY J.Zahicrowski for CELSIUS/WASA collab. Workshop on Eta Physics. Upp.sala. Szwec a. 25-27.10.2001 PION PRODUCTION IN pN COLLISIONS NEAR THRESHOLD J.Zlomanczuk-..., J.Stepaniak,..., J.Zabicrowski et al. AIP Con/S: Proc., Dec.2001, V,,o.603. 21, Mesons anid Light Nuclei: 8"'Conf 2001, Prague, Czech Republik, ed. hy J1Adams et al. oral talks HIGH ENERGY COSMIC GAMMA RAY REGISTRATION (FROM MEV TO 100 TEV) J.Szabelski 11'"International School ,,Pa r-ticle.s and Cosmology Baksan Volle', Kabardino-Balkaria, Russian Federation, April 18-24 2001 HADRONIC COLLISIONS AT VERY HIGH ENERGY I.Kurp 1/"' International Sclhool ,,Par-tic/les and Cos.vnologi", Baksani Valley, Kabardino-Balkaria, Russian Federation, April 18-24 2001 ASTROPHYSICAL REGISTRATION OF SIGNALS COMING 500-1000 MICROSECONDS AFTER THE MAIN EAS FRONT J.Gawin, K.J~di-zcjczak, J.Karczrnarczyk, S.Pachala, J.Swarzyiiski, B.Szabelska, .I.Szahelski, T.Wibig, A.F.Yanin et al. 27"' ICRC, Hamiburg, Geiniany, 8-15 .4ugust 2001 PRIMARY ENERGY DETERMINATION OF UHE EVENTS FROM PUBLISHED VOLCANO RANCH, YAKUTSK AND AGASA DATA J.N.Capdevielle, F.Colien, C.Le Gall, ,.Gawin, I.Kurp, B.Szabelska, .I.Szahelski, and T.Wibig 27" ICRC, Hamibuig, Gerpnany, 8-15 August 2001 THE PRIMARY ENERGY SPECTRUM OF COSMIC RAYS OBTAINED BY MUON DENSITY MEASUREMENTS AT KASCADE A.Haungs, . J.Zabierowski et al. (The KASCADE Collaboration) 27"' CRC, Hamiburg, Germany, R-15AIu.gut 2001 124 Annual Report 2001 NONPARAMETRIC DETERMINATION OF ENERGY SPECTRA AND MASS COMPOSITION OF PRIMARY COSMIC RAYS FOR SLANT DEPTH M.Roth, .. J.Zabierowski et al. (The KASCADE Collaboration) 27" ICRC, Hamnburg, Germany, 8-15 August 2001 A MEASUREMENT OF THE PRIMARY COSMIC RAY ENERGY SPECTRUM USING THE HADRONIC AIR SHOWER COMPONENT J.Hoerandel, ..., J.Zabierowski et al. (The KASCADE Collaboration) 271' ICRC, Hantbur,'g. Germany, 8-15 August 2001 HADRONIC INTERACTION MODELS AND THE AIR SHOWER SIMULATION PROGRAM D.Heck, ..., J.Zabierowski et al. (The KASCADE Collaboration) 27" ICRC, Hamburg, Gernmawn, 8-15 August 2001 KASCADE-GRANDE: A CONCLUSIVE EXPERIMENT ON THE KNEE M.Bertaina,..., J.Zabicrowski et al.
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