Records |
Author |
Martinez Torres, A.; Oset, E. |
Title |
Novel Interpretation of the “Theta(+)(1540) Pentaquark” Peak |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
105 |
Issue |
9 |
Pages |
092001 - 4pp |
Keywords |
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Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
We use a theoretical model of the gamma d --> K+K- np reaction adapted to the experiment done at LEPS where a peak was observed and associated with the Theta(+)(1540) pentaquark. The study shows that the method used in the experiment to assign momenta to the undetected proton and neutron, together with the chosen cuts, necessarily creates an artificial broad peak in the assumed K(+)n invariant mass in the region of the claimed Theta(+)(1540), such that the remaining strength seen for the experimental peak is compatible with a fluctuation of 2 sigma significance. |
Address |
[Martinez Torres, A.] Univ Valencia, Ctr Mixto, CSIC, Inst Invest Paterna,Dept Fis Teor, Valencia 46071, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9007 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000281272700005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
387 |
Permanent link to this record |
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Author |
Martinez Torres, A.; Khemchandani, K.P.; Navarra, F.S.; Nielsen, M.; Oset, E. |
Title |
The role of f(0)(1710) in the phi omega threshold peak of J/Psi -> gamma phi omega |
Type |
Journal Article |
Year |
2013 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
719 |
Issue |
4-5 |
Pages |
388-393 |
Keywords |
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Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
We study the process J/Psi -> gamma phi omega, measured by the BES experiment, where a neat peak close to the phi omega threshold is observed and is associated to a scalar meson resonance around 1800 MeV. We make the observation that a scalar resonance coupling to phi omega unavoidably couples strongly to K (K) over bar, but no trace of a peak is seen in the K (K) over bar spectrum of the J/Psi -> gamma K (K) over bar at this energy. This serves us to rule out the interpretation of the observed peak as a signal of a new resonance. After this is done, a thorough study is performed on the production of a pair of vector mesons and how its interaction leads necessarily to a peak in the J/Psi -> gamma phi omega reaction close to the phi omega threshold, due to the dynamical generation of the f(0)(1710) resonance by the vector-vector interaction. We then show that both the shape obtained for the phi omega mass distribution, as well as the strength are naturally reproduced by this mechanism. The work also explains why the phi omega peak is observed in the BES experiment and not in other reactions, like B-+/- -> K-+/-phi omega of Belle. |
Address |
[Martinez Torres, A.; Khemchandani, K. P.; Navarra, F. S.; Nielsen, M.; Oset, E.] Univ Sao Paulo, Inst Fis, BR-05389970 Sao Paulo, Brazil, Email: amartine@if.usp.br |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000315316900020 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1377 |
Permanent link to this record |
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Author |
Sekihara, T.; Martinez Torres, A.; Jido, D.; Oset, E. |
Title |
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 |
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Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
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 |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6001 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000300285400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
912 |
Permanent link to this record |
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Author |
Dai, L.R.; Oset, E.; Feijoo, A.; Molina, R.; Roca, L.; Martinez Torres, A.; Khemchandani, K.P. |
Title |
Masses and widths of the exotic molecular B-(s)(()*B-)((s))(*()) states |
Type |
Journal Article |
Year |
2022 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
105 |
Issue |
7 |
Pages |
074017 - 11pp |
Keywords |
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Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
We study the interaction of the doubly bottom systems BB, B*B, BsB, B-s*B, B*B*, B*B-S, B*B-s*, BsBs, BsBs*, B-s*B-s* by means of vector meson exchange with Lagrangians from an extension of the local hidden gauge approach. The full s-wave scattering matrix is obtained implementing unitarity in coupled channels by means of the Bethe-Salpeter equation. We find poles below the channel thresholds for the attractively interacting channels B*B in I = 0, B-s*B – B*B-s in I = 1/2, B* B* in I = 0, and B-s*B* in I = 1/2, all of them with J(P) = 1(+). For these cases the widths are evaluated identifying the dominant source of imaginary part. We find binding energies of the order of 10-20 MeV, and the widths vary much from one system to the other: of the order of 10-100 eV for the B* B system and B-s*B – B* B-s, about 6 MeV for the B*B* system and of the order of 0.5 MeV for the B-s*B* system. |
Address |
[Dai, L. R.] Huzhou Univ, Sch Sci, Huzhou 313000, Zhejiang, Peoples R China, Email: dailianrong@zjhu.edu.cn; |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2470-0010 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000809898400002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5317 |
Permanent link to this record |
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Author |
Aceti, F.; Bayar, M.; Oset, E.; Martinez Torres, A.; Khemchandani, K.P.; Dias, J.M.; Navarra, F.S.; Nielsen, M. |
Title |
Prediction of an I=1 D(D)over-bar* state and relationship to the claimed Z(c)(3900), Z(c)(3885) |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
90 |
Issue |
1 |
Pages |
016003 - 13pp |
Keywords |
|
Abstract ![sorted by Abstract field, descending order (down)](img/sort_desc.gif) |
We study here the interaction of D (D) over bar* in the isospin I = 1 channel in light of recent theoretical advances that allow us to combine elements of the local hidden gauge approach with heavy quark spin symmetry. We find that the exchange of light q (q) over bar is Okubo-Zweig-Iizuka (OZI) suppressed and thus we concentrate on the exchange of heavy vectors and of two pion exchange. The latter is found to be small compared to the exchange of heavy vectors, which then determines the strength of the interaction. A barely D (D) over bar* bound state decaying into eta(c)rho and pi J/psi is found. At the same time we reanalyze the data of the BESIII experiment on e(+)e(-) -> pi(+/-)(D (D) over bar*)(-/+), from where a Z(c)(3885) state was claimed, associated to a peak in the (D (D) over bar*)(-/+) invariant mass distribution close to threshold, and we find the data compatible with a resonance with mass around 3875 MeV and width around 30 MeV. We discuss the possibility that this and the Z(c)(3900) state found at BESIII, reconfirmed at 3894 MeV at Belle, or 3885 MeV at CLEO, could all be the same state and correspond to the one that we find theoretically. |
Address |
[Aceti, F.; Oset, E.; Dias, J. M.] Univ Valencia, Dept Fis Teor, Valencia 46071, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000339217800003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1845 |
Permanent link to this record |