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Salabura P. Hades experiment probing baryonic matter at SIS18 overview of results. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201713709008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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2
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Zhang R, Fu WJ, Liu YX. Properties of mesons in a strong magnetic field. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:307. [PMID: 27330406 PMCID: PMC4891378 DOI: 10.1140/epjc/s10052-016-4123-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/18/2016] [Indexed: 06/06/2023]
Abstract
By extending the [Formula: see text]-derivable approach in the Nambu-Jona-Lasinio model to a finite magnetic field we calculate the properties of pion, [Formula: see text], and [Formula: see text] mesons in a magnetic field at finite temperature not only in the quark-antiquark bound state scheme but also in the pion-pion scattering resonant state scenario. Our calculation as a result makes manifest that the masses of [Formula: see text] and [Formula: see text] meson can be nearly degenerate at the pseudo-critical temperature which increases with increasing magnetic field strength, and the [Formula: see text] mass ascends suddenly at almost the same critical temperature. Meanwhile the [Formula: see text] mesons' masses decrease with the temperature but increase with the magnetic field strength. We also check the Gell-Mann-Oakes-Renner relation and find that the relation can be violated clearly with increasing temperature, and the effect of the magnetic field becomes pronounced around the critical temperature. With different criteria, we analyze the effect of the magnetic field on the chiral phase transition and find that the pseudo-critical temperature of the chiral phase cross, [Formula: see text], is always enhanced by the magnetic field. Moreover, our calculations indicate that the [Formula: see text] mesons will get melted as the chiral symmetry has not yet been restored, but the [Formula: see text] meson does not disassociate even at very high temperature. Particularly, it is the first to show that there does not exist a vector meson condensate in the QCD vacuum in the pion-pion scattering scheme.
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Affiliation(s)
- Rui Zhang
- Department of Physics, State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, 100871 China
| | - Wei-jie Fu
- Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany
| | - Yu-xin Liu
- Department of Physics, State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, 100871 China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100871 China
- Center for High Energy Physics, Peking University, Beijing, 100871 China
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Lorenz M, Agakishiev G, Behnke C, Belver D, Belyaev A, Berger-Chen J, Blanco A, Blume C, Böhmer M, Cabanelas P, Chernenko S, Dritsa C, Dybczak A, Epple E, Fabbietti L, Fateev O, Fonte P, Friese J, Fröhlich I, Galatyuk T, Garzón JA, Gill K, Golubeva M, González-Díaz D, Guber F, Gumberidze M, Harabasz S, Hennino T, Höhne C, Holzmann R, Huck P, Ierusalimov A, Ivashkin A, Jurkovic M, Kämpfer B, Karavicheva T, Koenig I, Koenig W, Kolb BW, Korcyl G, Kornakov G, Kotte R, Krása A, Krebs E, Krizek F, Kuc H, Kugler A, Kurepin A, Kurilkin A, Kurilkin P, Ladygin V, Lalik R, Lang S, Lapidus K, Lebedev A, Lopes L, Maier L, Mangiarotti A, Markert J, Metag V, Michel J, Müntz C, Münzer R, Naumann L, Palka M, Parpottas Y, Pechenov V, Pechenova O, Pietraszko J, Przygoda W, Ramstein B, Rehnisch L, Reshetin A, Rustamov A, Sadovsky A, Salabura P, Scheib T, Schuldes H, Siebenson J, Sobolev Y, Spataro S, Ströbele H, Stroth J, Strzempek P, Sturm C, Svoboda O, Tarantola A, Teilab K, Tlusty P, Traxler M, Tsertos H, Vasiliev T, Wagner V, Weber M, Wendisch C, Wüstenfeld J, Yurevich S, Zanevsky Y. Low mass dielectrons radiated off cold nuclear matter measured with HADES. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146609011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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4
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Wood MH, Nasseripour R, Paolone M, Djalali C, Weygand DP, Adhikari KP, Anghinolfi M, Ball J, Battaglieri M, Batourine V, Bedlinskiy I, Bellis M, Berman BL, Biselli AS, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Careccia SL, Carman DS, Cole PL, Collins P, Crede V, D'Angelo A, Daniel A, De Vita R, De Sanctis E, Deur A, Dey B, Dhamija S, Dickson R, Doughty D, Dupre R, Egiyan H, El Alaoui A, El Fassi L, Eugenio P, Fegan S, Gabrielyan MY, Garçon M, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gohn W, Gothe RW, Graham L, Guidal M, Guo L, Hafidi K, Hakobyan H, Hanretty C, Hassall N, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Ishkhanov BS, Jawalkar SS, Jo HS, Joo K, Keller D, Khandaker M, Khetarpal P, Kim A, Kim W, Klein A, Klein FJ, Konczykowski P, Kubarovsky V, Kuleshov SV, Kuznetsov V, Livingston K, Martinez D, Mayer M, McAndrew J, McCracken ME, McKinnon B, Meyer CA, Mineeva T, Mirazita M, Mokeev V, Moreno B, Moriya K, Morrison B, Munevar E, Nadel-Turonski P, Ni A, Niccolai S, Niculescu G, Niculescu I, Niroula MR, Osipenko M, Ostrovidov AI, Paremuzyan R, Park K, Park S, Pasyuk E, Anefalos Pereira S, Pisano S, Pogorelko O, Pozdniakov S, Price JW, Procureur S, Prok Y, Protopopescu D, Raue BA, Ricco G, Ripani M, Rosner G, Rossi P, Sabatié F, Saini MS, Salamanca J, Salgado C, Schott D, Schumacher RA, Seder E, Seraydaryan H, Sharabian YG, Smith GD, Sober DI, Sokhan D, Stepanyan S, Stepanyan SS, Stoler P, Strakovsky II, Strauch S, Taiuti M, Tang W, Taylor CE, Tedeschi DJ, Tkachenko S, Ungaro M, Vernarsky B, Vineyard MF, Voutier E, Watts DP, Weinstein LB, Zhang J, Zhao B, Zhao ZW. Absorption of the ω and ϕ mesons in nuclei. PHYSICAL REVIEW LETTERS 2010; 105:112301. [PMID: 20867566 DOI: 10.1103/physrevlett.105.112301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Indexed: 05/29/2023]
Abstract
Because of their long lifetimes, the ω and ϕ mesons are the ideal candidates for the study of possible modifications of the in-medium meson-nucleon interaction through their absorption inside the nucleus. During the E01-112 experiment at the Thomas Jefferson National Accelerator Facility, the mesons were photoproduced from 2H, C, Ti, Fe, and Pb targets. This Letter reports the first measurement of the ratio of nuclear transparencies for the e+e- channel. The ratios indicate larger in-medium widths compared with what have been reported in other reaction channels. The absorption of the ω meson is stronger than that reported by the CBELSA-TAPS experiment and cannot be explained by recent theoretical models.
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Affiliation(s)
- M H Wood
- Canisius College, Buffalo, New York 14208, USA
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5
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Abuki H, Gatto R, Ruggieri M. Neutral quark matter in a Nambu–Jona-Lasinio model with vector interaction. Int J Clin Exp Med 2009. [DOI: 10.1103/physrevd.80.074019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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6
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Benabderrahmane ML, Herrmann N, Wiśniewski K, Kecskemeti J, Andronic A, Barret V, Basrak Z, Bastid N, Buehler P, Cargnelli M, Caplar R, Cordier E, Deppner I, Crochet P, Dupieux P, Dzelalija M, Fabbietti L, Fodor Z, Gasik P, Gasparić I, Grishkin Y, Hartmann ON, Hildenbrand KD, Hong B, Kang TI, Kienle P, Kirejczyk M, Kim YJ, Kis M, Koczoń P, Korolija M, Kotte R, Lebedev A, Leifels Y, Lopez X, Manko V, Marton J, Mangiarotti A, Merschmeyer M, Matulewicz T, Petrovici M, Piasecki K, Rami F, Reischl A, Reisdorf W, Rogowska M, Ryu MS, Schmidt P, Schüttauf A, Seres Z, Sikora B, Sim KS, Simion V, Siwek-Wilczyńska K, Smolyankin V, Suzuki K, Tymiński Z, Widmann E, Xiao ZG, Yamazaki T, Yushmanov I, Zhang XY, Zhilin A, Zmeskal J, Bratkovskaya E, Cassing W. Measurement of the in-medium K0 inclusive cross section in pi(-) -induced reactions at 1.15 GeV/c. PHYSICAL REVIEW LETTERS 2009; 102:182501. [PMID: 19518864 DOI: 10.1103/physrevlett.102.182501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 03/20/2009] [Indexed: 05/27/2023]
Abstract
The K0 meson production by pi(-) mesons of 1.15 GeV/c momentum on C, Al, Cu, Sn, and Pb nuclear targets was measured with the FOPI spectrometer at the Schwer-Ionen-Synchrotron accelerator of GSI. Inclusive production cross sections and the momentum distributions of K0 mesons are compared to scaled elementary production cross sections and to predictions of theoretical models describing the in-medium production of kaons. The data represent a new reference for those models, which are widely used for interpretation of the strangeness production in heavy-ion collisions. The presented results demonstrate the sensitivity of the kaon production to the reaction amplitudes inside nuclei and point to the existence of a repulsive KN potential of 20+/-5 MeV at normal nuclear matter density.
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7
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Kotulla M, Trnka D, Mühlich P, Anton G, Bacelar JCS, Bartholomy O, Bayadilov D, Beloglazov YA, Bogendörfer R, Castelijns R, Crede V, Dutz H, Ehmanns A, Elsner D, Ewald R, Fabry I, Fuchs M, Essig K, Funke C, Gothe R, Gregor R, Gridnev AB, Gutz E, Höffgen S, Hoffmeister P, Horn I, Hössl J, Jaegle I, Junkersfeld J, Kalinowsky H, Klein F, Klein F, Klempt E, Konrad M, Kopf B, Krusche B, Langheinrich J, Löhner H, Lopatin IV, Lotz J, Lugert S, Menze D, Messchendorp JG, Mertens T, Metag V, Mosel U, Nanova M, Novotny R, Ostrick M, Pant LM, van Pee H, Pfeiffer M, Roy A, Radkov A, Schadmand S, Schmidt C, Schmieden H, Schoch B, Shende S, Suft G, Sumachev VV, Szczepanek T, Süle A, Thoma U, Varma R, Walther D, Weinheimer C, Wendel C. Modification of the omega-meson lifetime in nuclear matter. PHYSICAL REVIEW LETTERS 2008; 100:192302. [PMID: 18518443 DOI: 10.1103/physrevlett.100.192302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Indexed: 05/26/2023]
Abstract
Information on hadron properties in the nuclear medium has been derived from the photoproduction of omega mesons on the nuclei C, Ca, Nb, and Pb using the Crystal Barrel/TAPS detector at the ELSA tagged photon facility in Bonn. The dependence of the omega-meson cross section on the nuclear mass number has been compared with three different types of models: a Glauber analysis, a Boltzmann-Uehling-Uhlenbeck analysis of the Giessen theory group, and a calculation by the Valencia theory group. In all three cases, the inelastic omega width is found to be 130-150 MeV/c(2) at normal nuclear matter density for an average 3-momentum of 1.1 GeV/c. In the rest frame of the omega meson, this inelastic omega width corresponds to a reduction of the omega lifetime by a factor approximately 30. For the first time, the momentum dependent omegaN cross section has been extracted from the experiment and is in the range of 70 mb.
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Affiliation(s)
- M Kotulla
- II Physikalisches Institut, Universität Giessen, Giessen, Germany
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8
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Holt JW, Brown GE, Kuo TTS, Holt JD, Machleidt R. Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions. PHYSICAL REVIEW LETTERS 2008; 100:062501. [PMID: 18352465 DOI: 10.1103/physrevlett.100.062501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Indexed: 05/26/2023]
Abstract
We present shell model calculations for the beta decay of 14C to the 14N ground state, treating the states of the A=14 multiplet as two 0p holes in an 16O core. We employ low-momentum nucleon-nucleon (NN) interactions derived from the realistic Bonn-B potential and find that the Gamow-Teller (GT) matrix element is too large to describe the known lifetime. By using a modified version of this potential that incorporates the effects of Brown-Rho scaling medium modifications, we find that the GT matrix element vanishes for a nuclear density around 85% that of nuclear matter. We find that the splitting between the (J(pi),T)=(1(+),0) and (J(pi),T)=(0(+),1) states in 14N is improved using the medium-modified Bonn-B potential and that the transition strengths from excited states of 14C to the 14N ground state are compatible with recent experiments.
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Affiliation(s)
- J W Holt
- Department of Physics, SUNY, Stony Brook, New York 11794, USA
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9
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Nasseripour R, Wood MH, Djalali C, Weygand DP, Tur C, Mosel U, Muehlich P, Adams G, Amaryan MJ, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Battaglieri M, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Blaszczyk L, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Casey L, Chen S, Cole PL, Collins P, Coltharp P, Crabb D, Crannell H, Crede V, Cummings JP, Dashyan N, De Masi R, De Vita R, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Dickson R, Dodge GE, Doughty D, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Feldman G, Feuerbach RJ, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gordon CIO, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hakobyan RS, Hanretty C, Hardie J, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Johnstone JR, Joo K, Juengst HG, Kalantarians N, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Krahn Z, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Li J, Livingston K, Lu HY, Maccormick M, Markov N, Mattione P, McAleer S, McKinnon B, McNabb JWC, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Moriya K, Morrow SA, Moteabbed M, Mueller J, Munevar E, Mutchler GS, Nadel-Turonski P, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Anefalos Pereira S, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Sabatié F, Salamanca J, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shvedunov NV, Smith ES, Smith LC, Sober DI, Sokhan D, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Tkabladze A, Tkachenko S, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Williams M, Wolin E, Yegneswaran A, Zana L, Zhang B, Zhang J, Zhao B, Zhao ZW. Search for medium modifications of the rho meson. PHYSICAL REVIEW LETTERS 2007; 99:262302. [PMID: 18233570 DOI: 10.1103/physrevlett.99.262302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Indexed: 05/25/2023]
Abstract
The photoproduction of vector mesons on various nuclei has been studied using the CLAS detector at Jefferson Laboratory. The vector mesons, rho, omega, and varphi, are observed via their decay to e;{+}e;{-}, in order to reduce the effects of final-state interactions in the nucleus. Of particular interest are possible in-medium effects on the properties of the rho meson. The rho mass spectrum is extracted from the data on various nuclei, 2H, C, Fe, and Ti. We observe no significant mass shift and some broadening consistent with expected collisional broadening for the rho meson.
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Affiliation(s)
- R Nasseripour
- University of South Carolina, Columbia, South Carolina 29208, USA
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Sakuma F, Chiba J, En'yo H, Fukao Y, Funahashi H, Hamagaki H, Ieiri M, Ishino M, Kanda H, Kitaguchi M, Mihara S, Miwa K, Miyashita T, Murakami T, Muto R, Nakura T, Naruki M, Ozawa K, Sasaki O, Sekimoto M, Tabaru T, Tanaka KH, Togawa M, Yamada S, Yokkaichi S, Yoshimura Y. Nuclear-matter modification of decay widths in the phi-->e+e- and phi-->K+K- channels. PHYSICAL REVIEW LETTERS 2007; 98:152302. [PMID: 17501340 DOI: 10.1103/physrevlett.98.152302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Indexed: 05/15/2023]
Abstract
The invariant mass spectra of phi-->K+K- are measured in 12 GeV p+A reactions in order to search for the in-medium modification of phi mesons. The observed K+K- spectra are well reproduced by the relativistic Breit-Wigner function with a combinatorial background shape in three betagamma regions between 1.0 and 3.5. The nuclear mass number dependence of the yields of the K+K- decay channel is compared to the simultaneously measured e+e- decay channel for carbon and copper targets. We parameterize the production yields as sigma(A)=sigma0Aalpha and obtain alphaphi-->K+K- -alphaphi-->e+e- to be 0.14+/-0.12. Limits are obtained for the partial decay widths of the phi mesons in nuclear matter.
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Affiliation(s)
- F Sakuma
- Department of Physics, Kyoto University, Kitashirakawa Sakyo-ku, Kyoto 606-8502, Japan.
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11
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Muto R, Chiba J, En'yo H, Fukao Y, Funahashi H, Hamagaki H, Ieiri M, Ishino M, Kanda H, Kitaguchi M, Mihara S, Miwa K, Miyashita T, Murakami T, Nakura T, Naruki M, Ozawa K, Sakuma F, Sasaki O, Sekimoto M, Tabaru T, Tanaka KH, Togawa M, Yamada S, Yokkaichi S, Yoshimura Y. Evidence for in-medium modification of the phi meson at normal nuclear density. PHYSICAL REVIEW LETTERS 2007; 98:042501. [PMID: 17358757 DOI: 10.1103/physrevlett.98.042501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 09/11/2006] [Indexed: 05/14/2023]
Abstract
Invariant mass spectra of e(+) e(-) pairs have been measured in 12 GeV p + A reactions to detect possible in-medium modification of vector mesons. Copper and carbon targets are used to study the nuclear-size dependence of e(+) e(-) invariant mass distributions. A significant excess on the low-mass side of the phi meson peak is observed in the low betagamma(= beta/square root(1-beta(2))) region of phi mesons (betagamma < 1.25) with copper targets. However, in the high betagamma region (betagamma > 1.25), spectral shapes of phi mesons are well described by the Breit-Wigner shape when experimental effects are considered. Thus, in addition to our earlier publications on rho/omega modification, this study has experimentally verified vector meson mass modification at normal nuclear density.
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Affiliation(s)
- R Muto
- RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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12
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Hartmann M, Maeda Y, Keshelashvili I, Koch HR, Mikirtytchiants S, Barsov S, Borgs W, Büscher M, Dimitrov VI, Dymov S, Hejny V, Kleber V, Koptev V, Kulessa P, Mersmann T, Merzliakov S, Mussgiller A, Nekipelov M, Nioradze M, Ohm H, Pysz K, Schleichert R, Stein HJ, Ströher H, Watzlawik KH, Wüstner P. Near-threshold production of phi mesons in pp collisions. PHYSICAL REVIEW LETTERS 2006; 96:242301. [PMID: 16907232 DOI: 10.1103/physrevlett.96.242301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Indexed: 05/11/2023]
Abstract
The pp-->ppphi reaction has been studied at the Cooler Synchrotron COSY-Jülich, using the internal beam and ANKE facility. Total cross sections have been determined at three excess energies epsilon near the production threshold. The differential cross section closest to threshold at epsilon=18.5 MeV exhibits a clear S wave dominance as well as a noticeable effect due to the proton-proton final-state interaction. Taken together with data for ppomega production, a significant enhancement of the phi/omega ratio of a factor 8 is found compared to predictions based on the Okubo-Zweig-Iizuka rule.
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Affiliation(s)
- M Hartmann
- Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany.
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