| Article | |
| Report number | arXiv:2005.14471 ; DESY-20-080 |
| Title | Measurement of exclusive $\pi^+ \pi ^-$ and $\rho^0$ meson photoproduction at HERA |
| Related title | Measurement of Exclusive $\pi^{+}\pi^{-}$ and $\rho^0$ Meson Photoproduction at HERA |
| Author(s) |
Andreev, V. (Lebedev Inst.) ; Baghdasaryan, A. (Yerevan Phys. Inst.) ; Baty, A. (Rice U.) ; Begzsuren, K. (Ulan Bator, Inst. Phys. Tech.) ; Belousov, A. (Lebedev Inst.) ; Bolz, A. (DESY ; Heidelberg U.) ; Boudry, V. (Ecole Polytechnique) ; Brandt, G. (Gottingen U., II. Phys. Inst.) ; Britzger, D. (Munich, Max Planck Inst.) ; Buniatyan, A. (Birmingham U.) ; Bystritskaya, L. (Moscow, ITEP) ; Campbell, A.J. (DESY) ; Cantun Avila, K.B. (Merida, IPN) ; Cerny, K. (Palacky U.) ; Chekelian, V. (Munich, Max Planck Inst.) ; Chen, Z. (Shandong U.) ; Contreras, J.G. (Merida, IPN) ; Cvach, J. (Cracow, INP) ; Dainton, J.B. (Liverpool U.) ; Daum, K. (Wuppertal U.) ; Deshpande, A. (SUNY, Stony Brook) ; Diaconu, C. (Marseille, CPPM) ; Eckerlin, G. (DESY) ; Egli, S. (PSI, Villigen) ; Elsen, E. (CERN) ; Favart, L. (Brussels U., IIHE) ; Fedotov, A. (Moscow, ITEP) ; Feltesse, J. (IRFU, SPP, Saclay) ; Fleischer, M. (DESY) ; Fomenko, A. (Lebedev Inst.) ; Gal, C. (SUNY, Stony Brook) ; Gayler, J. (DESY) ; Goerlich, L. (Cracow, INP) ; Gogitidze, N. (Lebedev Inst.) ; Gouzevitch, M. (Lyon, IPN) ; Grab, C. (Zurich, ETH) ; Grebenyuk, A. (Brussels U., IIHE) ; Greenshaw, T. (Liverpool U.) ; Grindhammer, G. (Munich, Max Planck Inst.) ; Haidt, D. (DESY) ; Henderson, R.C.W. (Lancaster U.) ; Hladky, J. (Cracow, INP) ; Hoffmann, D. (Marseille, CPPM) ; Horisberger, R. (PSI, Villigen) ; Hreus, T. (Brussels U., IIHE) ; Huber, F. (Heidelberg U.) ; Jacquet, M. (Orsay, LAL) ; Janssen, X. (Brussels U., IIHE) ; Jung, A.W. (Purdue U.) ; Jung, H. (DESY) ; Kapichine, M. (Dubna, JINR) ; Katzy, J. (DESY) ; Kiesling, C. (Munich, Max Planck Inst.) ; Klein, M. (Liverpool U.) ; Kleinwort, C. (DESY) ; Kogler, R. (Hamburg U.) ; Kostka, P. (Liverpool U.) ; Kretzschmar, J. (Liverpool U.) ; Krücker, D. (DESY) ; Krüger, K. (DESY) ; Landon, M.P.J. (Queen Mary, U. of London) ; Lange, W. (DESY, Zeuthen) ; Laycock, P. (Liverpool U.) ; Lebedev, A. (Lebedev Inst.) ; Levonian, S. (DESY) ; Lipka, K. (DESY) ; List, B. (DESY) ; List, J. (DESY) ; Li, W. (Rice U.) ; Lobodzinski, B. (Munich, Max Planck Inst.) ; Malinovski, E. (Lebedev Inst.) ; Martyn, H.-U. (RWTH Aachen U.) ; Maxfield, S.J. (Liverpool U.) ; Mehta, A. (Liverpool U.) ; Meyer, A.B. (DESY) ; Meyer, H. (Wuppertal U.) ; Meyer, J. (DESY) ; Mikocki, S. (Cracow, INP) ; Mondal, M.M. (SUNY, Stony Brook) ; Morozov, A. (Dubna, JINR) ; Müller, K. (Zurich U.) ; Naumann, Th. (DESY) ; Newman, P.R. (Birmingham U.) ; Niebuhr, C. (DESY) ; Nowak, G. (Cracow, INP) ; Olsson, J.E. (DESY) ; Ozerov, D. (PSI, Villigen) ; Park, S. (SUNY, Stony Brook) ; Pascaud, C. (Orsay, LAL) ; Patel, G.D. (Liverpool U.) ; Perez, E. (CERN) ; Petrukhin, A. (Lyon, IPN) ; Picuric, I. (Montenegro U.) ; Pitzl, D. (DESY) ; Polifka, R. (Charles U.) ; Radescu, V. (Oxford U.) ; Raicevic, N. (Montenegro U.) ; Ravdandorj, T. (Ulan Bator, Inst. Phys. Tech.) ; Reimer, P. (Cracow, INP) ; Rizvi, E. (Queen Mary, U. of London) ; Robmann, P. (Zurich U.) ; Roosen, R. (Brussels U., IIHE) ; Rostovtsev, A. (IITP, Moscow) ; Rotaru, M. (Bucharest, IFIN-HH) ; Sankey, D.P.C. (Rutherford) ; Sauter, M. (Heidelberg U.) ; Sauvan, E. (Marseille, CPPM ; Annecy, LAPP) ; Schmitt, S. (DESY) ; Schmookler, B.A. (SUNY, Stony Brook) ; Schoeffel, L. (IRFU, SPP, Saclay) ; Schöning, A. (Heidelberg U.) ; Sefkow, F. (DESY) ; Shushkevich, S. (Moscow State U.) ; Soloviev, Y. (Lebedev Inst.) ; Sopicki, P. (Cracow, INP) ; South, D. (DESY) ; Spaskov, V. (Dubna, JINR) ; Specka, A. (Ecole Polytechnique) ; Steder, M. (DESY) ; Stella, B. (Rome III U.) ; Straumann, U. (Zurich U.) ; Sykora, T. (Charles U.) ; Thompson, P.D. (Birmingham U.) ; Traynor, D. (Queen Mary, U. of London) ; Truöl, P. (Zurich U.) ; Tseepeldorj, B. (Ulan Bator, Inst. Phys. Tech. ; Mongolian Natl. U.) ; Tu, Z. (Brookhaven) ; Valkárová, A. (Charles U.) ; Vallée, C. (Marseille, CPPM) ; Van Mechelen, P. (Brussels U., IIHE) ; Wegener, D. (Dortmund U.) ; Wünsch, E. (DESY) ; Žáček, J. (Charles U.) ; Zhang, J. (SUNY, Stony Brook) ; Zhang, Z. (Orsay, LAL) ; Žlebčík, R. (DESY) ; Zohrabyan, H. (Yerevan Phys. Inst.) ; Zomer, F. (Orsay, LAL) |
| Publication | 2020-12-23 |
| Imprint | 2020-05-29 |
| Number of pages | 54 |
| Note | 74 pages, 20 figures, 23 tables, accepted by EPJC. Figure numbering updated. Ancillary material has been updated |
| In: | Eur. Phys. J. C 80 (2020) 1189 |
| DOI | 10.1140/epjc/s10052-020-08587-3 |
| Subject category | hep-ph ; Particle Physics - Phenomenology ; hep-ex ; Particle Physics - Experiment |
| Accelerator/Facility, Experiment | DESY HERA H1 |
| Abstract | Exclusive photoproduction of $\rho^0(770)$ mesons is studied using the H1 detector at the $ep$ collider HERA. A sample of about 900000 events is used to measure single- and double-differential cross sections for the reaction $\gamma p \to \pi^{+}\pi^{-}Y$. Reactions where the proton stays intact (${m_Y{=}m_p}$) are statistically separated from those where the proton dissociates to a low-mass hadronic system ($m_p{<}m_Y{<}10$ GeV). The double-differential cross sections are measured as a function of the invariant mass $m_{\pi\pi}$ of the decay pions and the squared $4$-momentum transfer $t$ at the proton vertex. The measurements are presented in various bins of the photon-proton collision energy $W_{\gamma p}$. The phase space restrictions are $0.5 < m_{\pi\pi} < 2.2$ GeV, ${\vert t\vert < 1.5}$ GeV${}^2$, and ${20 < W_{\gamma p} < 80}$ GeV. Cross section measurements are presented for both elastic and proton-dissociative scattering. The observed cross section dependencies are described by analytic functions. Parametrising the $m_{\pi\pi}$ dependence with resonant and non-resonant contributions added at the amplitude level leads to a measurement of the $\rho^{0}(770)$ meson mass and width at $m_\rho = 770.8\ {}^{+2.6}_{-2.7}$ (tot) MeV and $\Gamma_\rho = 151.3\ {}^{+2.7}_{-3.6}$ (tot) MeV, respectively. The model is used to extract the $\rho^0(770)$ contribution to the $\pi^{+}\pi^{-}$ cross sections and measure it as a function of $t$ and $W_{\gamma p}$. In a Regge asymptotic limit in which one Regge trajectory $\alpha(t)$ dominates, the intercept $\alpha(t{=}0) = 1.0654\ {}^{+0.0098}_{-0.0067}$ (tot) and the slope $\alpha^\prime(t{=}0) = 0.233\ {}^{+0.067 }_{-0.074 }$ (tot) GeV${}^{-2}$ of the $t$ dependence are extracted for the case $m_Y{=}m_p$. |
| Copyright/License | preprint: (License: arXiv nonexclusive-distrib 1.0) publication: © 2020-2024 The Author(s) (License: CC-BY-4.0), sponsored by SCOAP³ |
Corresponding record in: Inspire
Record created 2020-07-01, last modified 2022-01-26