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A Measurement of the Proton Structure Function F2(X; DESY ISSN January A Measurement of the Proton Structure Function F x Q H Collab oration Abstract 2 A measurement of the proton structure function F x Q is rep orted for mo 2 2 2 2 mentum transfers squared Q b etween GeV and GeV and for Bjorken 4 x b etween and using data collected by the HERA exp eriment H in It is observed that F increases signicantly with decreasing x conrming 2 our previous measurement made with one tenth of the data available in this analy 2 sis The Q dep endence is approximately logarithmic over the full kinematic range covered The subsample of deep inelastic events with a large pseudorapidity gap in the hadronic energy ow close to the proton remnant is used to measure the diractive contribution to F 2 submitted to Nucl Phys B H Collab oration 3 13 3540 24 28 11 T Ahmed S Aid A Akhundov V Andreev B Andrieu RD Appuhn 36 26 35 17 24 29 11 M Arpagaus A Babaev J Baehr J Ban P Baranov E Barrelet W Bartel 4 29 37 11 24 1 M Barth U Bassler HP Beck HJ Behrend A Belousov Ch Berger 1 29 36 4 9 H Bergstein G Bernardi R Bernet G BertrandCoremans M Besancon 11 22 27 13 8 4 R Beyer P Biddulph JC Bizot V Blob el K Borras F Botterweck 28 14 11 1 27 17 V Boudry A Braemer F Brasse W Braunschweig V Brisson D Bruncko 15 11 13 11 13 1139 C Brune RBuchholz L Bungener J Burger FW Busser A Buniatian 18 26 11 26 11 5 S Burke G Buschhorn AJ Campb ell T Carli F Charles D Clarke 18 4 8 8 19 5 AB Clegg B Clerbaux M Colomb o JG Contreras C Cormack JA Coughlan 27 9 9 11 5 30 A Courau Ch Coutures G Cozzika L Criegee DG Cussans J Cvach 29 19 23 16 34 9 S Dagoret JB Dainton M Danilov WD Dau K Daum M David 11 27 29 11 4 32 E Deur B Delcourt L Del Buono A De Ro eck EA De Wolf P Di Nezza 37 3 2 23 29 13 C Dollfus JD Dowell HB Dreis V Droutskoi J Dub o c D Dullmann 13 12 34 19 11 23 37 O Dunger H Duhm J Eb ert TR Eb ert G Eckerlin V Efremenko S Egli 35 37 36 14 20 H Ehrlichmann S Eichenb erger R Eichler F Eisele E Eisenhandler 22 11 14 36 4 4 RJ Ellison E Elsen M Erdmann W Erdmann E Evrard L Favart 23 13 11 9 15 32 A Fedotov D Feeken R Felst J Feltesse J Ferencei F Ferrarotto 11 11 26 2 24 23 K Flamm M Fleischer M Flieser G Flugge A Fomenko B Fominykh 7 31 22 11 12 19 M Forbush J Formanek JM Foster G Franke E Fretwurst E Gabathuler 33 26 3 11 8 11 K Gabathuler K Gamerdinger J Garvey J Gayler M Gebauer A Gellrich 1 11 11 6 24 29 H Genzel R Gerhards U Go erlach L Go erlich N Gogitidze M Goldb erg 8 29 23 23 36 2 D Goldner B GonzalezPineiro I Gorelov P Goritchev C Grab H Grassler 2 19 26 26 16 35 R Grassler T Greenshaw G Grindhammer A Grub er C Grub er J Haack 11 6 29 1 18 11 D Haidt L Ha jduk O Hamon M Hamp el EM Hanlon M Hapke 5 20 13 18 35 WJ Haynes J Heatherington G Heinzelmann RCW Henderson H Henschel 1 30 26 11 5 35 R Herma I Herynek MF Hess W Hildesheim P Hill KH Hiller 22 30 22 8 33 3 CD Hilton J Hladk y KC Ho eger M Hoppner R Horisb erger VL Hudgson 4 8 14 22 1 9 Ph Huet M Hutte H Hufnagel M Ibb otson H Itterb eck MA Jabiol 27 21 27 15 11 21 A Jacholkowska C Jacobsson M Jare J Janoth T Jansen L Jonsson 13 4 18 29 20 20 K Johannsen DP Johnson L Johnson H Jung PIP Kalmus D Kant 2 12 16 14 35 R Kaschowitz P Kasselmann U Kathage J Katzy HH Kaufmann 11 3 25 1 26 35 S Kazarian IR Kenyon S Kermiche C Keuker C Kiesling M Klein 13 11 7 1 26 8 7 C Kleinwort G Knies W Ko T Kohler J Kohne H Kolanoski F Kole 22 11 8 35 24 8 SD Kolya V Korb el M Korn P Kostka SK Kotelnikov T Kramerkamp er 629 11 2 11 11 MW Krasny H Krehbiel D Kruc ker U Kruger U KrunerMarquis 26 2 26 17 8 34 JP Kub enka H Kuster M Kuhlen T Kurca J Kurzhofer B Kuznik 29 28 7 20 35 26 D Lacour F Lamarche R Lander MPJ Landon W Lange P Lanius 9 24 11 1124 2 8 JF Lap orte A Leb edev C Leverenz S Levonian Ch Ley A Lindner 12 11 13 11 27 21 G Lindstrom F Linsel J Lipinski B List P Lo ch H Lohmander 20 23 811 34 24 7 GC Lop ez V Lubimov D Luk e N Magnussen E Malinovski S Mani 17 4 25 22 34 11 R Maracek P Marage J Marks R Marshall J Martens R Martin 1 6 2 20 19 HU Martyn J Martyniak S Masson T Mavroidis SJ Maxeld 19 22 15 22 11 37 SJ McMahon A Mehta K Meier D Mercer T Merz CA Meyer 34 11 6 19 28 5 6 H Meyer J Meyer S Miko cki D Milstead F Moreau JV Morris E Mro czko 11 37 17 23 35 13 G Muller K Muller P Murn V Nagovizin R Nahnhauer B Naroska 35 3 18 29 29 3 Th Naumann PR Newman D Newton D Neyret HK Nguyen TC Nicholls 13 11 1 6 5 21 F Nieb ergall C Niebuhr R Nisius G Nowak GW Noyes M Nyb ergWerther 19 26 8 11 12 4 M Oakden H Ob erlack U Obro ck JE Olsson E Panaro A Panitch 27 19 35 9 22 12 36 C Pascaud GD Patel E Pepp el E Perez JP Phillips Ch Pichler D Pitzl 7 11 11 11 1 30 11 G Pop e S Prell R Prosi G Radel F Raupach P Reimer S Reinshagen 26 8 12 36 13 2 20 P Ribarics HRick V Riech J Riedlb erger S Riess M Rietz E Rizvi 3 37 35 4 1 SM Rob ertson P Robmann HE Rolo R Ro osen K Rosenbauer 23 7 9 26 24 6 20 A Rostovtsev F Rouse C Royon K Ruter S Rusakov K Rybicki R Rylko 2 26 5 23 26 11 N Sahlmann E Sanchez DPC Sankey M Savitsky P Schacht S Schiek 14 20 11 34 13 11 P Schlep er W von Schlipp e C Schmidt D Schmidt G Schmidt A Schoning 11 26 14 35 13 11 V Schroder E Schuhmann B Schwab A Schwind U Seehausen F Sefkow 12 11 23 23 24 26 M Seidel R Sell A Semenov V Shekelyan I Sheviakov H Sho oshtari 24 16 16 28 10 24 LN Shtarkov G Siegmon U Siewert Y Sirois IO Skillicorn P Smirnov 7 24 8 13 1 13 JR Smith Y Soloviev J Spiekermann H Spitzer R Starosta M Steenb o ck 11 2 32 22 11 15 35 P Steen R Steinb erg B Stella K Stephens J Stier J Stiewe U Stosslein 30 37 2 3 15 J Strachota U Straumann W Struczinski JP Sutton S Tapprogge 3827 23 28 20 37 6 RE Taylor V Tchernyshov C Thiebaux G Thompson P Truol J Turnau 14 2 24 31 31 25 4 J Tutas P Uelkes A Usik S Valkar A Valkarova C Vallee P Van Esch 4 1139 24 30 9 9 P Van Mechelen A Vartap etian Y Vazdik M Vecko P Verrecchia G Villet 8 2 33 18 8 13 K Wacker A Wagener M Wagener IW Walker A Walther G Web er 11 8 11 26 3 7 M Web er D Wegener A Wegner HP Wellisch LR West S Willard 35 11 22 11 11 29 M Winde GG Winter AE Wright E Wunsc h N Wul TP Yiou 31 12 27 23 11 11 J Zacek D Zarb o ck Z Zhang A Zhokin M Zimmer W Zimmermann 27 15 F Zomer and K Zub er 1 a I Physikalisches Institut der RWTH Aachen Germany 2 a III Physikalisches Institut der RWTH Aachen Germany 3 b School of Physics and Space Research University of Birmingham Birmingham UK 4 InterUniversity Institute for High Energies ULBVUB Brussels Universitaire Instel ling c Antwerpen Wilrijk Belgium 5 b Rutherford Appleton Laboratory Chilton Didcot UK 6 d Institute for Nuclear Physics Cracow Poland 7 e Physics Department and IIRPA University of California Davis California USA 8 a Institut fur Physik Universitat Dortmund Dortmund Germany 9 CEA DSMDAPNIA CESaclay GifsurYvette France 10 b Department of Physics and Astronomy University of Glasgow Glasgow UK 11 a DESY Hamburg Germany 12 a I Institut fur Experimentalphysik Universitat Hamburg Hamburg Germany 13 a II Institut fur Experimentalphysik Universitat Hamburg Hamburg Germany 14 a Physikalisches Institut Universitat Heidelberg Heidelberg Germany 15 a Institut fur Hochenergiephysik Universitat Heidelberg Heidelberg Germany 16 a Institut fur Reine und Angewandte Kernphysik Universitat Kiel Kiel Germany 17 f Institute of Experimental Physics Slovak Academy of Sciences Kosice Slovak Republic 18 b School of Physics and Materials University of Lancaster Lancaster UK 19 b Department of Physics University of Liverpool Liverpool UK 20 b Queen Mary and Westeld Col lege London UK 21 g Physics Department University of Lund Lund Sweden 22 b Physics Department University of Manchester Manchester UK 23 Institute for Theoretical and Experimental Physics Moscow Russia 24 f Lebedev Physical Institute Moscow Russia 25 CPPM Universite dAixMarseil le II INPCNRS Marseil le France 26 a MaxPlanckInstitut fur Physik Munchen Germany 27 LAL Universite de ParisSud INPCNRS Orsay France 28 LPNHE Ecole Polytechnique INPCNRS Palaiseau France 29 LPNHE Universites Paris VI and VII INPCNRS Paris France 30 f h Institute of Physics Czech Academy of Sciences Praha Czech Republic 31 f h Nuclear Center Charles University Praha Czech Republic 32 INFN Roma and Dipartimento di Fisica Universita La Sapienza Roma Italy 33 Paul Scherrer Institut Vil ligen Switzerland 34 Fachbereich Physik Bergische Universitat Gesamthochschule Wuppertal Wuppertal a Germany 35 a DESY Institut fur Hochenergiephysik Zeuthen Germany 36 i Institut fur Teilchenphysik ETH Zurich Switzerland 37 i PhysikInstitut der Universitat Zurich Zurich Switzerland 38 Stanford Linear Accelerator Center Stanford California USA 39 Visitor from Yerevan PhysInst Armenia 40 a Visitor from Institute of Physics Azerbaijan Academy of Sciences Baku Azerbaijan Supported by the Bundesministerium fur Forschung und Technologie FRG under contract numbers ACP ACP DOI HHP HHI HDI HDI KIP MPI and WTP b Supported by the UK Particle Physics and Astronomy Research Council and formerly by the UK Science and Engineering Research Council c Supported by FNRSNFWO IISNIIKW d Supported by the Polish State Committee for Scientic Research grant No e Supported in part by USDOE grant DE F ER f Supported by the Deutsche Forschungsgemeinschaft
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