Elastic and proton-dissociative ρ0 photoproduction at HERA

被引:156
作者
Breitweg, J
Derrick, M
Krakauer, D
Magill, S
Mikunas, D
Musgrave, B
Repond, J
Stanek, R
Talaga, RL
Yoshida, R
Zhang, H
Mattingly, MCK
Anselmo, F
Antonioli, P
Bari, G
Basile, M
Bellagamba, L
Boscherini, D
Bruni, A
Bruni, G
Romeo, GC
Castellini, G
Chiarini, M
Cifarelli, L
Cindolo, F
Contin, A
Corradi, M
De Pasquale, S
Gialas, I
Giusti, P
Iacobucci, G
Laurenti, G
Levi, G
Margotti, A
Massam, T
Nania, R
Nemoz, C
Palmonari, F
Pesci, A
Polini, A
Ricci, F
Sartorelli, G
Garcia, YZ
Zichichi, A
Amelung, C
Bornheim, A
Brock, I
Coboken, K
Crittenden, J
Deffner, R
机构
[1] Argonne Natl Lab, Argonne, IL 60439 USA
[2] Andrews Univ, Berrien Springs, MI 49104 USA
[3] Univ Bologna, Bologna, Italy
[4] Ist Nazl Fis Nucl, I-40126 Bologna, Italy
[5] Univ Bonn, Inst Phys, D-5300 Bonn, Germany
[6] Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England
[7] Univ Calabria, Dept Phys, I-87036 Cosenza, Italy
[8] INFN, I-87036 Cosenza, Italy
[9] Chonnam Natl Univ, Kwangju, South Korea
[10] Columbia Univ, Nevis Labs, Irvington, NY USA
[11] Inst Nucl Phys, Krakow, Poland
[12] Acad Min & Met, Fac Phys & Nucl Tech, Krakow, Poland
[13] Jagiellonian Univ, Dept Phys, Krakow, Poland
[14] DESY, D-2000 Hamburg, Germany
[15] DESY, IFH, Zeuthen, Germany
[16] Univ Florence, Florence, Italy
[17] Ist Nazl Fis Nucl, I-50125 Florence, Italy
[18] Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy
[19] Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany
[20] Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland
[21] Univ Hamburg, Inst Expt Phys 1, Hamburg, Germany
[22] Univ Hamburg, Inst Expt Phys 2, Hamburg, Germany
[23] Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London, England
[24] Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA
[25] Forschungszentrum Julich, Inst Kernphys, Julich, Germany
[26] KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki, Japan
[27] Korea Univ, Seoul 136701, South Korea
[28] Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain
[29] McGill Univ, Dept Phys, Montreal, PQ, Canada
[30] Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan
[31] Moscow Phys Engn Inst, Moscow, Russia
[32] Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia
[33] NIKHEF H, NL-1009 DB Amsterdam, Netherlands
[34] Univ Amsterdam, Amsterdam, Netherlands
[35] Ohio State Univ, Dept Phys, Columbus, OH 43210 USA
[36] Univ Oxford, Dept Phys, Oxford, England
[37] Univ Padua, Dipartimento Fis, Padua, Italy
[38] Ist Nazl Fis Nucl, Padua, Italy
[39] Penn State Univ, Dept Phys, University Pk, PA 16802 USA
[40] Polytech Univ, Sagamihara, Kanagawa, Japan
[41] Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy
[42] Ist Nazl Fis Nucl, Rome, Italy
[43] Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England
[44] Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA
[45] Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys, IL-69978 Tel Aviv, Israel
[46] Univ Tokyo, Dept Phys, Tokyo 113, Japan
[47] Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan
[48] Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy
[49] Univ Turin, Fac Sci 2, Turin, Italy
[50] Ist Nazl Fis Nucl, I-10125 Turin, Italy
来源
EUROPEAN PHYSICAL JOURNAL C | 1998年 / 2卷 / 02期
关键词
D O I
10.1007/s100520050136
中图分类号
O412 [相对论、场论]; O572.2 [粒子物理学];
学科分类号
摘要
Elastic and proton-dissociative p(o) photoproduction (gamma p --> rho(o)p, gamma p --> rho(o)N, respectively, with rho(o) --> pi(+)pi(-)) has been studied in ep interactions at HERA for photon-proton centre-of-mass energies in the range 50 < W < 100 GeV and for \t\ < 0.5 GeV2, where t is the square of the four-momentum transfer at the proton vertex; the results on the proton-dissociative reaction are presented for masses of the dissociated proton system in the range M-N(2) < 0.1W(2). For the elastic process, the pi(+)pi(-) invariant mass spectrum has been investigated as a function of t. As in fixed target experiments, the rho(o) resonance shape is asymmetric; this asymmetry decreases with increasing \t\, as expected in models in which the asymmetry is ascribed to the interference of resonant and non-resonant pi(+)pi(-) production. The cross section has been studied as a function of W; a fit to the resonant part with the form W-a gives a = 0.16 +/- 0.06 (stat.)(-0.15)(+0.11) (syst.). The resonant part of the gamma p --> pi(+)pi(-) p cross section is 11.2 +/- 0.1 (stat.)(-1.2)(+1.1)(syst.) mu b at [W] = 71.7 GeV. The t dependence of the cross section can be described by a function of the type A(rho) exp (-b(rho)\t\ + c(p)t(2)) with b(rho) = 10.9 +/- 0.3 (stat.)(-0.5)(+1.0) (syst.) GeV-2 and c(rho) = 2.7 +/- 0.9 (stat.)(-1.7)(+1.9) (syst.) GeV-4. The t dependence has also been studied as a function of W and a value of the slope of the pomeron trajectory alpha(IP)' = 0.23 +/- 0.15 (stat.)(-0.07)(+0.10), (syst.) GeV-2 has been deduced. The rho(o) spin density matrix elements r(00)(04), r(1-1)(04) and Re[r(10)(04)] have been measured and found to be consistent with expectations based on s-channel helicity conservation. For proton-dissociative pi(+)pi(-) photoproduction in the rho(o) mass range, the distributions of the two-pion invariant mass, Wi and the polar and azimuthal angles of the pions in the helicity frame are the same within errors as those for the elastic process. The t distribution has been fitted to an exponential function with a slope parameter 5.8 +/- 0.3 (stat.) +/- 0.5 (syst.) GeV-2. The ratio of the elastic to proton-dissociative rho(o) photoproduction cross section is 2.0 +/- 0.2 (stat.) +/- 0.7 (syst.).
引用
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页码:247 / 267
页数:21
相关论文
共 88 条
[1]   MEASUREMENT OF SMALL-ANGLE ANTIPROTON-PROTON ELASTIC-SCATTERING AT ROOT-S=546 AND 1800 GEV [J].
ABE, F ;
ALBROW, M ;
AMIDEI, D ;
ANWAYWIESE, C ;
APOLLINARI, G ;
ATAC, M ;
AUCHINCLOSS, P ;
AZZI, P ;
BACCHETTA, N ;
BADEN, AR ;
BADGETT, W ;
BAILEY, MW ;
BAMBERGER, A ;
DEBARBARO, P ;
BARBAROGALTIERI, A ;
BARNES, VE ;
BARNETT, BA ;
BAUER, G ;
BAUMANN, T ;
BEDESCHI, F ;
BEHRENDS, S ;
BELFORTE, S ;
BELLETTINI, G ;
BELLINGER, J ;
BENJAMIN, D ;
BENLLOCH, J ;
BENSINGER, J ;
BERETVAS, A ;
BERGE, JP ;
BERTOLUCCI, S ;
BIERY, K ;
BHADRA, S ;
BINKLEY, M ;
BISELLO, D ;
BLAIR, R ;
BLOCKER, C ;
BODEK, A ;
BOLOGNESI, V ;
BOOTH, AW ;
BOSWELL, C ;
BRANDENBURG, G ;
BROWN, D ;
BUCKLEYGEER, E ;
BUDD, HS ;
BUSETTO, G ;
BYONWAGNER, A ;
BYRUM, KL ;
CAMPAGNARI, C ;
CAMPBELL, M ;
CANER, A .
PHYSICAL REVIEW D, 1994, 50 (09) :5518-5534
[2]   MEASUREMENT OF (P)OVER-BAR-P SINGLE DIFFRACTION DISSOCIATION AT ROOT-S=546 AND 1800 GEV [J].
ABE, F ;
ALBROW, M ;
AMIDEI, D ;
ANWAYWIESE, C ;
APOLLINARI, G ;
ATAC, M ;
AUCHINCLOSS, P ;
AZZI, P ;
BACCHETTA, N ;
BADEN, AR ;
BADGETT, W ;
BAILEY, MW ;
BAMBERGER, A ;
DEBARBARO, P ;
BARBAROGALTIERI, A ;
BARNES, VE ;
BARNETT, BA ;
BAUER, G ;
BAUMANN, T ;
BEDESCHI, F ;
BEHRENDS, S ;
BELFORTE, S ;
BELLETTINI, G ;
BELLINGER, J ;
BENJAMIN, D ;
BENLLOCH, J ;
BENSINGER, J ;
BERETVAS, A ;
BERGE, JP ;
BERTOLUCCI, S ;
BIERY, K ;
BHADRA, S ;
BINKLEY, M ;
BISELLO, D ;
BLAIR, R ;
BLOCKER, C ;
BODEK, A ;
BOLOGNESI, V ;
BOOTH, AW ;
BOSWELL, C ;
BRANDENBURG, G ;
BROWN, D ;
BUCKLEYGEER, E ;
BUDD, HS ;
BUSETTO, G ;
BYONWAGNER, A ;
BYRUM, KL ;
CAMPAGNARI, C ;
CAMPBELL, M ;
CANER, A .
PHYSICAL REVIEW D, 1994, 50 (09) :5535-5549
[3]   Proton dissociative rho and elastic phi electroproduction at HERA [J].
Adloff, C ;
Aid, S ;
Anderson, M ;
Andreev, V ;
Andrieu, B ;
Arkadov, V ;
Arndt, C ;
Ayyaz, I ;
Babaev, A ;
Bahr, J ;
Ban, J ;
Baranov, P ;
Barrelet, E ;
Barschke, R ;
Bartel, W ;
Bassler, U ;
Beck, HP ;
Beck, M ;
Behrend, HJ ;
Belousov, A ;
Berger, C ;
Bernardi, G ;
BertrandCoremans, G ;
Beyer, R ;
Biddulph, P ;
Bizot, JC ;
Borras, K ;
Botterweck, F ;
Boudry, V ;
Bourov, S ;
Braemer, A ;
Braunschweig, W ;
Brisson, V ;
Brown, DP ;
Bruckner, W ;
Bruel, P ;
Bruncko, D ;
Brune, C ;
Burger, J ;
Busser, FW ;
Buniatian, A ;
Burke, S ;
Buschhorn, G ;
Calvet, D ;
Campbell, AJ ;
Carli, T ;
Charlet, M ;
Clarke, D ;
Clerbaux, B ;
Cocks, S .
ZEITSCHRIFT FUR PHYSIK C-PARTICLES AND FIELDS, 1997, 75 (04) :607-618
[4]   Elastic and inelastic photoproduction of J/psi mesons at HERA [J].
Aid, S ;
Andreev, V ;
Andrieu, B ;
Appuhn, RD ;
Arpagaus, M ;
Babaev, A ;
Bahr, J ;
Ban, J ;
Ban, Y ;
Baranov, P ;
Barrelet, E ;
Barschke, R ;
Bartel, W ;
Barth, M ;
Bassler, U ;
Beck, E ;
Behrend, HJ ;
Belousov, A ;
Berger, C ;
Bernardi, G ;
Bernet, R ;
BertrandCoremans, G ;
Besancon, M ;
Beyer, R ;
Biddulph, P ;
Bispham, P ;
Bizot, JC ;
Blobel, V ;
Borras, K ;
Botterweck, F ;
Boudry, V ;
Braemer, A ;
Braunschweig, W ;
Brisson, V ;
Bruncko, D ;
Brune, C ;
Buchholz, R ;
Bungener, L ;
Burger, J ;
Busser, FW ;
Buniatian, A ;
Burke, S ;
Burton, MJ ;
Buschhorn, G ;
Campbell, AJ ;
Carli, T ;
Charles, F ;
Charlet, M ;
Clarke, D ;
Clegg, AB .
NUCLEAR PHYSICS B, 1996, 472 (1-2) :3-31
[5]   Elastic photoproduction of rho(0) mesons at HERA [J].
Aid, S ;
Andreev, V ;
Andrieu, B ;
Appuhn, RD ;
Arpagaus, M ;
Babaev, A ;
Bahr, J ;
Ban, J ;
Ban, Y ;
Baranov, P ;
Barrelet, E ;
Barschke, R ;
Bartel, W ;
Barth, M ;
Bassler, U ;
Beck, HP ;
Behrend, HJ ;
Belousov, A ;
Berger, C ;
Bernardi, G ;
Bernet, R ;
BertrandCoremans, G ;
Besancon, M ;
Beyer, R ;
Biddulph, P ;
Bispham, P ;
Bizot, JC ;
Blobel, V ;
Borras, K ;
Botterweck, F ;
Boudry, V ;
Braemer, A ;
Braunschweig, W ;
Brisson, V ;
Bruncko, D ;
Brune, C ;
Buchholz, R ;
Bungener, L ;
Burger, J ;
Busser, FW ;
Buniatian, A ;
Burke, S ;
Burton, MJ ;
Buschhorn, G ;
Campbell, AJ ;
Carli, T ;
Charles, F ;
Charlet, M ;
Clarke, D ;
Clegg, AB .
NUCLEAR PHYSICS B, 1996, 463 (01) :3-29
[6]   DIFFRACTION OF SUB-NUCLEAR WAVES [J].
ALBERI, G ;
GOGGI, G .
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS, 1981, 74 (01) :3-207
[7]   INELASTIC DIFFRACTIVE SCATTERING AT CERN ISR [J].
ALBROW, MG ;
BAGCHUS, A ;
BARBER, DP ;
BENZ, P ;
BOGAERTS, A ;
BOSNJAKOVIC, B ;
BROOKS, JR ;
CHANG, CY ;
CLEGG, AB ;
ERNE, FC ;
GEE, CNP ;
KOOIJMAN, P ;
LOCKE, DH ;
LOEBINGER, FK ;
MCCUBBIN, NA ;
MURPHY, PG ;
RADOJICIC, D ;
RUDGE, A ;
SENS, JC ;
SESSOMS, AL ;
SINGH, J ;
STORK, D ;
TIMMER, J .
NUCLEAR PHYSICS B, 1976, 108 (01) :1-29
[8]   COMPARATIVE-STUDY OF P0 PHOTOPRODUCED ON D,N AND P AT 7.5 GEV [J].
ALEXANDER, G ;
BENARY, O ;
GANDSMAN, J ;
LEVY, A ;
LISSAUER, D ;
OREN, Y .
NUCLEAR PHYSICS B, 1976, 104 (03) :397-412
[9]   STUDY OF RHO-0 PRODUCTION IN GAMMA-D, GAMMA-P AND GAMMA-N REACTIONS AT 7.5 GEV USING LINEARLY POLARIZED PHOTON BEAM [J].
ALEXANDER, G ;
GANDSMAN, J ;
LEVY, A ;
LISSAUER, D ;
ROSENSTEIN, LM .
NUCLEAR PHYSICS B, 1974, B 69 (03) :445-453
[10]   PHOTOPRODUCTION OF NEUTRAL RHO MESONS [J].
ALVENSLE.H ;
BECKER, U ;
BERTRAM, WK ;
CHEN, M ;
COHEN, KJ ;
KNASEL, TM ;
MARSHALL, R ;
QUINN, DJ ;
ROHDE, M ;
SANDERS, GH ;
SCHUBEL, H ;
TING, SCC .
NUCLEAR PHYSICS B, 1970, B 18 (02) :333-&