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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Measurement of exclusive π+π- and ρ meson photoproduction at HERA: H1 Collaboration
AU - Andreev, V.
AU - Baghdasaryan, A.
AU - Baty, A.
AU - Begzsuren, K.
AU - Belousov, A.
AU - Bolz, A.
AU - Boudry, V.
AU - Brandt, G.
AU - Britzger, D.
AU - Buniatyan, A.
AU - Bystritskaya, L.
AU - Campbell, A.J.
AU - Cantun Avila, K.B.
AU - Cerny, K.
AU - Chekelian, V.
AU - Chen, Z.
AU - Contreras, J.G.
AU - Cvach, J.
AU - Dainton, J.B.
AU - Daum, K.
AU - Deshpande, A.
AU - Diaconu, C.
AU - Eckerlin, G.
AU - Egli, S.
AU - Elsen, E.
AU - Favart, L.
AU - Fedotov, A.
AU - Feltesse, J.
AU - Fleischer, M.
AU - Fomenko, A.
AU - Gal, C.
AU - Gayler, J.
AU - Goerlich, L.
AU - Gogitidze, N.
AU - Gouzevitch, M.
AU - Grab, C.
AU - Grebenyuk, A.
AU - Greenshaw, T.
AU - Grindhammer, G.
AU - Haidt, D.
AU - Henderson, R.C.W.
AU - Hladkỳ, J.
AU - Hoffmann, D.
AU - Horisberger, R.
AU - Hreus, T.
AU - Huber, F.
AU - Jacquet, M.
AU - Janssen, X.
AU - Jung, A.W.
AU - Jung, H.
AU - Kapichine, M.
AU - Katzy, J.
AU - Kiesling, C.
AU - Klein, M.
AU - Kleinwort, C.
AU - Kogler, R.
AU - Kostka, P.
AU - Kretzschmar, J.
AU - Krücker, D.
AU - Krüger, K.
AU - Landon, M.P.J.
AU - Lange, W.
AU - Laycock, P.
AU - Lebedev, A.
AU - Levonian, S.
AU - Lipka, K.
AU - List, B.
AU - List, J.
AU - Li, W.
AU - Lobodzinski, B.
AU - Malinovski, E.
AU - Martyn, H.-U.
AU - Maxfield, S.J.
AU - Mehta, A.
AU - Meyer, A.B.
AU - Meyer, H.
AU - Meyer, J.
AU - Mikocki, S.
AU - Mondal, M.M.
AU - Morozov, A.
AU - Müller, K.
AU - Naumann, T.
AU - Newman, P.R.
AU - Niebuhr, C.
AU - Nowak, G.
AU - Olsson, J.E.
AU - Ozerov, D.
AU - Park, S.
AU - Pascaud, C.
AU - Patel, G.D.
AU - Perez, E.
AU - Petrukhin, A.
AU - Picuric, I.
AU - Pitzl, D.
AU - Polifka, R.
AU - Radescu, V.
AU - Raicevic, N.
AU - Ravdandorj, T.
AU - Reimer, P.
AU - Rizvi, E.
AU - Robmann, P.
AU - Roosen, R.
AU - Rostovtsev, A.
AU - Rotaru, M.
AU - Sankey, D.P.C.
AU - Sauter, M.
AU - Sauvan, E.
AU - Schmitt, S.
AU - Schmookler, B.A.
AU - Schoeffel, L.
AU - Schöning, A.
AU - Sefkow, F.
AU - Shushkevich, S.
AU - Soloviev, Y.
AU - Sopicki, P.
AU - South, D.
AU - Spaskov, V.
AU - Specka, A.
AU - Steder, M.
AU - Stella, B.
AU - Straumann, U.
AU - Sykora, T.
AU - Thompson, P.D.
AU - Traynor, D.
AU - Truöl, P.
AU - Tseepeldorj, B.
AU - Tu, Z.
AU - Valkárová, A.
AU - Vallée, C.
AU - Van Mechelen, P.
AU - Wegener, D.
AU - Wünsch, E.
AU - Žáček, J.
AU - Zhang, J.
AU - Zhang, Z.
AU - Žlebčík, R.
AU - Zohrabyan, H.
AU - Zomer, F.
PY - 2020/12/23
Y1 - 2020/12/23
N2 - Exclusive photoproduction of ρ(770) mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900,000 events is used to measure single- and double-differential cross sections for the reaction γp→ π+π-Y. Reactions where the proton stays intact (mY= mp) are statistically separated from those where the proton dissociates to a low-mass hadronic system (mp<mY<10GeV). The double-differential cross sections are measured as a function of the invariant mass mππ 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 Wγp. The phase space restrictions are 0.5≤mππ≤2.2GeV, |t|≤1.5GeV2, and 20≤Wγp≤80GeV. Cross section measurements are presented for both elastic and proton-dissociative scattering. The observed cross section dependencies are described by analytic functions. Parametrising the mππ dependence with resonant and non-resonant contributions added at the amplitude level leads to a measurement of the ρ(770) meson mass and width at mρ=770.8-2.7+2.6(tot.)MeV and Γρ=151.3-3.6+2.7(tot.)MeV, respectively. The model is used to extract the ρ(770) contribution to the π+π- cross sections and measure it as a function of t and Wγp. In a Regge asymptotic limit in which one Regge trajectory α(t) dominates, the intercept α(t=0)=1.0654-0.0067+0.0098(tot.) and the slope α′(t=0)=0.233-0.074+0.067(tot.)GeV-2 of the t dependence are extracted for the case mY= mp.
AB - Exclusive photoproduction of ρ(770) mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900,000 events is used to measure single- and double-differential cross sections for the reaction γp→ π+π-Y. Reactions where the proton stays intact (mY= mp) are statistically separated from those where the proton dissociates to a low-mass hadronic system (mp<mY<10GeV). The double-differential cross sections are measured as a function of the invariant mass mππ 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 Wγp. The phase space restrictions are 0.5≤mππ≤2.2GeV, |t|≤1.5GeV2, and 20≤Wγp≤80GeV. Cross section measurements are presented for both elastic and proton-dissociative scattering. The observed cross section dependencies are described by analytic functions. Parametrising the mππ dependence with resonant and non-resonant contributions added at the amplitude level leads to a measurement of the ρ(770) meson mass and width at mρ=770.8-2.7+2.6(tot.)MeV and Γρ=151.3-3.6+2.7(tot.)MeV, respectively. The model is used to extract the ρ(770) contribution to the π+π- cross sections and measure it as a function of t and Wγp. In a Regge asymptotic limit in which one Regge trajectory α(t) dominates, the intercept α(t=0)=1.0654-0.0067+0.0098(tot.) and the slope α′(t=0)=0.233-0.074+0.067(tot.)GeV-2 of the t dependence are extracted for the case mY= mp.
U2 - 10.1140/epjc/s10052-020-08587-3
DO - 10.1140/epjc/s10052-020-08587-3
M3 - Journal article
VL - 80
JO - European Physical Journal C: Particles and Fields
JF - European Physical Journal C: Particles and Fields
SN - 1434-6044
IS - 12
M1 - 1189
ER -