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Author Noguera, S.; Vento, V.
Title (up) The pion transition form factor and the pion distribution amplitude Type Journal Article
Year 2010 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 46 Issue 2 Pages 197-205
Keywords
Abstract Recent BaBar data on the pion transition form factor, whose Q(2)-dependence is much steeper then predicted by asymptotic Quantum Chromodynamics (QCD), have caused a renewed interest in its theoretical description. We present here a formalism based on a model-independent description for low photon virtuality and a high photon virtuality description based on QCD, which match at a scale Q(0). The high photon virtuality description incorporates a flat pion distribution amplitude, phi(x) = 1, at the matching scale Q(0) and QCD evolution from Q(0) to Q > Q(0). The flat pion distribution is connected, through soft pion theorems and chiral symmetry, to the pion valence parton distribution at the same low scale Q(0). The procedure leads to a good description of the data, and by incorporating additional twist-three effects, to an excellent description of the data.
Address [Noguera, S.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Valencia, Spain, Email: Santiago.Noguera@uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes ISI:000284869600005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 312
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Author Barucca, G. et al; Diaz, J.
Title (up) The potential of Lambda and Xi(-) studies with PANDA at FAIR Type Journal Article
Year 2021 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 57 Issue 4 Pages 154 - 26pp
Keywords
Abstract The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss groundstate hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: (p) over barp -> (Lambda) over bar Lambda and (p) over barp -> (Xi) over bar+Xi(-). The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.
Address [Barucca, G.; Davi, F.; Lancioni, G.; Mengucci, P.; Montalto, L.; Natali, P. P.; Paone, N.; Rinaldi, D.; Scalise, L.] Univ Politecn Marche Ancona, Ancona, Italy, Email: karin.schonning@physics.uu.se
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000645914600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4799
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Author Xiao, C.W.; Aceti, F.; Bayar, M.
Title (up) The small K pi component in the K* wave functions Type Journal Article
Year 2013 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 49 Issue 2 Pages 22 - 5pp
Keywords
Abstract We use a recently developed formalism which generalizes Weinberg's compositeness condition to partial waves higher than s-wave in order to determine the probability of having a K pi component in the K* wave function. A fit is made to the K pi phase shifts in p-wave, from where the coupling of K* to K pi and the K pi loop function are determined. These ingredients allow us to determine that the K* is a genuine state, different from a K pi component, in a proportion of about 80%.
Address [Xiao, C. W.; Aceti, F.; Bayar, M.] Ctr Mixto Univ Valencia CSIC, Inst Invest Paterna, Dept Fis Teor, Valencia 46071, Spain, Email: xiaochw@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000315601600006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1359
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Author Ramos, A.; Tolos, L.; Molina, R.; Oset, E.
Title (up) The width of the omega meson in the nuclear medium Type Journal Article
Year 2013 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 49 Issue 11 Pages 148 - 16pp
Keywords
Abstract We evaluate the width of the omega meson in nuclear matter. We consider the free decay mode of the omega into three pions, which is dominated by rho IEuro decay, and replace the rho and pi propagators by their medium-modified ones. We also take into account the quasielastic and inelastic processes induced by a vector-baryon interaction dominated by vector meson exchange, as well as the contributions coming from the mechanism with medium-modified K , propagators. We obtain a substantial increase of the omega width in the medium, reaching a value of 121 +/- 10 MeV at normal nuclear matter density for an omega at rest, which comes mainly from omega N -> pi pi N, omega NN -> pi NN processes associated to the dominant omega -> rho IEuro decay mode. The value of the width increases moderately with momentum, reaching values of around 200MeV at 600MeV/c.
Address [Ramos, A.] Univ Barcelona, Dept Estruct & Constituents Mat, E-08028 Barcelona, Spain, Email: ramos@ecm.ub.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000327460400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1654
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Author Sekihara, T.; Martinez Torres, A.; Jido, D.; Oset, E.
Title (up) Theoretical study of incoherent phi photoproduction on a deuteron target Type Journal Article
Year 2012 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 48 Issue 1 Pages 10 - 17pp
Keywords
Abstract We study the photoproduction of phi mesons in deuteron, paying attention to the modification of the cross-section from bound protons to the free ones. For this purpose we take into account Fermi motion in single scattering and rescattering of phi to account for phi absorption on a second nucleon as well as the rescattering of the proton on the neutron. We find that the contribution of the double scattering for phi is much smaller than the typical cross-section of gamma p -> phi p in free space, which implies a very small screening of the phi production in deuteron. The contribution from the proton rescattering, on the other hand, is found to be not negligible compared to the cross-section of gamma p -> phi p in free space, and leads to a moderate reduction of the phi photoproduction cross-section on a deuteron at forward angles if the LEPS set-up is taken into account. The Fermi motion allows contribution of the single scattering in regions forbidden by phase-space in the free case. In particular, we find that for momentum transfer squared close to the maximum value, the Fermi motion changes drastically the shape of d sigma/dt, to the point that the ratio of this cross-section to the free one becomes very sensitive to the precise value of t chosen, or the size of the bin used in an experimental analysis. Hence, this particular region of t does not seem to be the most indicated to find effects of a possible phi absorption in the deuteron. This reaction is studied theoretically as a function of t and the results are contrasted with recent experiments at LEPS and Jefferson Lab. The effect of the experimental angular cuts at LEPS is also discussed, providing guidelines for future experimental analyses of the reaction.
Address [Sekihara, T.] Kyoto Univ, Grad Sch Sci, Dept Phys, Kyoto 6068502, Japan, Email: sekihara@th.phys.titech.ac.jp
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000300285400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 912
Permanent link to this record