| Records |
| Author |
Nagahiro, H.; Hirenzaki, S.; Oset, E.; Ramos, A. |
| Title |
eta '-Nucleus optical potential and possible eta ' bound states |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
709 |
Issue |
1-2 |
Pages |
87-92 |
| Keywords |
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| Abstract |
Starting from a recent model of the eta'N interaction, we evaluate the eta'-nucleus optical potential, including the contribution of lowest order in density, t rho/2m(eta'), together with the second-order terms accounting for eta' absorption by two nucleons. We also calculate the formation cross section of the eta' bound states from (pi(+), p) reactions on nuclei. The eta'-nucleus potential suffers from uncertainties tied to the poorly known eta'N interaction, which can be partially constrained by the experimental modulus of the eta'N scattering length and/or the recently measured transparency ratios in eta' nuclear photoproduction. Assuming an attractive interaction and taking the claimed experimental value vertical bar a(eta'N)vertical bar = 0.1 fm, we obtain an eta' optical potential in nuclear matter at saturation density of V eta' = -(8.7 + 1.8i) MeV, not attractive enough to produce eta' bound states in light nuclei. Larger values of the scattering length give rise to deeper optical potentials, with moderate enough imaginary parts. For a value vertical bar a(eta'N)vertical bar = 0.3 fm, which can still be considered to lie within the uncertainties of the experimental constraints, the spectra of light and medium nuclei show clear structures associated to eta'-nuclear bound states and to threshold enhancements in the unbound region. |
| Address |
[Nagahiro, H.; Hirenzaki, S.] Nara Womens Univ, Dept Phys, Nara 6308506, Japan, Email: nagahiro@rcnp.osaka-u.ac.jp |
| 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 |
|
Conference |
|
| Notes |
WOS:000302111200013 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
979 |
| Permanent link to this record |
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| |
| Author |
Nanova, M. et al; Oset, E. |
| Title |
Transparency ratio in gamma A -> eta ' A ' and the in-medium eta ' width |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
710 |
Issue |
4-5 |
Pages |
600-606 |
| Keywords |
|
| Abstract |
The photoproduction of eta'-mesons off different nuclei has been measured with the CBELSA/TAPS detector system for incident photon energies between 1500-2200 MeV. The transparency ratio has been deduced and compared to theoretical calculations describing the propagation of eta'-mesons in nuclei. The comparison indicates a width of the eta'-meson of the order of Gamma = 15-25 MeV at rho = rho(0) for an average momentum p(eta') = 1050 MeV/c, at which the eta'-meson is produced in the nuclear rest frame. The inelastic eta'N cross section is estimated to be 3-10 mb. Parameterizing the photoproduction cross section of eta'-mesons by sigma(A) = sigma(0)A(alpha), a value of alpha = 0.84 +/- 0.03 has been deduced. |
| Address |
[Nanova, M.; Metag, V.; Makonyi, K.; Gregor, R.; Lugert, S.; Novotny, R.; Pant, L. M.; Pfeiffer, M.; Roy, A.; Schadmand, S.; Trnka, D.; Varma, R.] Univ Giessen, Inst Phys 2, D-35390 Giessen, Germany, Email: mariana.nanova@exp2.physik.uni-giessen.de |
| 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:000303221800012 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1008 |
| Permanent link to this record |
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| Author |
Oset, E.; Martinez Torres, A.; Khemchandani, K.P.; Roca, L.; Yamagata-Sekihara, J. |
| Title |
Two, three, many body systems involving mesons |
Type |
Journal Article |
| Year |
2012 |
Publication |
Progress in Particle and Nuclear Physics |
Abbreviated Journal |
Prog. Part. Nucl. Phys. |
| Volume |
67 |
Issue |
2 |
Pages |
455-460 |
| Keywords |
Meson many body; Chiral dynamics; Dynamically generated resonances |
| Abstract |
In this talk we show recent developments on few body systems involving mesons. We report on an approach to Faddeev equations using chiral unitary dynamics, where an explicit cancellation of the two body off shell amplitude with three body forces stemming from the same chiral Lagrangians takes place. This removal of the unphysical off shell part of the amplitudes is most welcome and renders the approach unambiguous, showing that only on shell two body amplitudes need to be used. Within this approach, systems of two mesons and one baryon are studied, reproducing properties of the low lying 1/2(+) states. On the other hand we also report on multirho and K* multirho states which can be associated to known meson resonances of high spin. |
| Address |
[Oset, E.; Yamagata, J.] Ctr Mixto CSIC UV, Inst Fis Corpuscular, Inst Invest Paterna, Valencia 46071, Spain, Email: oset@ific.uv.es |
| 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 |
0146-6410 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000303282200060 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
998 |
| Permanent link to this record |
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| Author |
Bayar, M.; Oset, E. |
| Title |
Improved fixed center approximation of the Faddeev equations for the (K)over-bar N N system with S=0 |
Type |
Journal Article |
| Year |
2012 |
Publication |
Nuclear Physics A |
Abbreviated Journal |
Nucl. Phys. A |
| Volume |
883 |
Issue |
|
Pages |
57-68 |
| Keywords |
Fixed center approximation; (K)over-bar N N system |
| Abstract |
We extend the Fixed Center Approximation (FCA) to the Faddeev equations for the (K) over bar N N system with S = 0, including the charge exchange mechanisms in the (K) over bar rescattering which have been ignored in former works within the FCA. We obtain similar results to those found before, but the binding is reduced by 6 MeV. At the same time we also evaluate the explicit contribution the pi N Sigma intermediate state in the three body system and find that it produces and additional small decrease in the binding of about 3 MeV. The system appears bound by about 35 MeV and the width omitting two body absorption, is about 50 MeV. |
| Address |
[Bayar, M.; Oset, E.] Inst Invest Paterna, Inst Fis Corpuscular, Ctr Mixto, CSIC,UV, Valencia 46071, Spain, Email: melahat@ific.uv.es |
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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 |
0375-9474 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000304628900005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1042 |
| 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 |
|
| Abstract |
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 |
|
| 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 |
Martinez Torres, A.; Khemchandani, K.P.; Jido, D.; Kanada-En'yo, Y.; Oset, E. |
| Title |
Three-body hadron systems with strangeness |
Type |
Journal Article |
| Year |
2013 |
Publication |
Nuclear Physics A |
Abbreviated Journal |
Nucl. Phys. A |
| Volume |
914 |
Issue |
|
Pages |
280-288 |
| Keywords |
Unitary chiral theories; Few-body systems |
| Abstract |
Recently, many efforts are being put in studying three-hadron systems made of mesons and baryons and interesting results are being found. In this talk, we summarize the main features of the formalism used to study such three hadron systems with strangeness S = -1, 0 within a framework built on the basis of unitary chiral theories and solution of the Faddeev equations. In particular, we present the results obtained for the pi(K) over barN, K (K) over barN and KK (K) over bar systems and their respective coupled channels. In the first case, we find four Sigma's and two A's with spin-parity J(P) = 1/2(+), in the 1500-1800 MeV region, as two meson-one baryon s-wave resonances. In the second case, a 1/2(+) N* around 1900 MeV is found. For the last one a kaon close to 1420 MeV is formed, which can be identified with K(1460). |
| Address |
[Torres, A. Martinez; Khemchandani, K. P.] Univ Sao Paulo, Inst Fis, BR-05314970 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 |
0375-9474 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
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Conference |
|
| Notes |
WOS:000324847700036 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1596 |
| Permanent link to this record |
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| |
| Author |
Bayar, M.; Oset, E. |
| Title |
The (K)over-barNN system revisited including absorption |
Type |
Journal Article |
| Year |
2013 |
Publication |
Nuclear Physics A |
Abbreviated Journal |
Nucl. Phys. A |
| Volume |
914 |
Issue |
|
Pages |
349-353 |
| Keywords |
Few-body systems |
| Abstract |
We present the Fixed Center Approximation (FCA) to the Faddeev equations for the (K) over bar NN system with S = 0, including the charge exchange mechanisms in the (K) over bar rescattering. The system appears bound by about 35 MeV and the width, omitting two body absorption, is about 50 MeV. We also evaluate the (K) over bar absorption width in the bound (K) over bar NN system by employing the FCA to account for (K) over bar rescattering on the NN cluster. The width of the states found previously for S = 0 and S = 1 is found now to increase by about 30 MeV due to the (K) over bar NN absorption, to a total value of about 80 MeV. |
| Address |
[Bayar, M.; Oset, E.] Inst Invest Paterna, Inst Fis Corpuscular, Ctr Mixto CSIC UV, Valencia 46071, Spain, Email: melahat.bayar@kocaeli.edu.tr |
| 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 |
0375-9474 |
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:000324847700048 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1597 |
| Permanent link to this record |
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| Author |
Tolos, L.; Cabrera, D.; Garcia-Recio, C.; Molina, R.; Nieves, J.; Oset, E.; Ramos, A.; Romanets, O.; Salcedo, L.L. |
| Title |
Strangeness and charm in nuclear matter |
Type |
Journal Article |
| Year |
2013 |
Publication |
Nuclear Physics A |
Abbreviated Journal |
Nucl. Phys. A |
| Volume |
914 |
Issue |
|
Pages |
461-471 |
| Keywords |
Strange mesons; Transparency ratio; Dynamically-generated baryon resonances; Open charm in matter; D-mesic nuclei |
| Abstract |
The properties of strange (K, (K) over bar and (K) over bar*) and open-charm (D, (D) over bar and D*) mesons in dense matter are studied using a unitary approach in coupled channels for meson-baryon scattering. In the strangeness sector, the interaction with nucleons always comes through vector-meson exchange, which is evaluated by chiral and hidden gauge Lagrangians. For the interaction of charmed mesons with nucleons we extend the SU(3) Weinberg-Tomozawa Lagrangian to incorporate spin-flavor symmetry and implement a suitable flavor symmetry breaking. The in-medium solution for the scattering amplitude accounts for Pauli blocking effects and meson self-energies. On one hand, we obtain the K, (K) over bar and (K) over bar* spectral functions in the nuclear medium and study their behaviour at finite density, temperature and momentum. We also make an estimate of the transparency ratio of the gamma A -> K+ K*(-) A' reaction, which we propose as a tool to detect in-medium modifications of the (K) over bar* meson. On the other hand, in the charm sector, several resonances with negative parity are generated dynamically by the s-wave interaction between pseudoscalar and vector meson multiplets with 1/2(+) and 3/2(+) baryons. The properties of these states in matter are analyzed and their influence on the open-charm meson spectral functions is studied. We finally discuss the possible formation of D-mesic nuclei at FAIR energies. |
| Address |
[Tolos, Laura] Fac Ciencies, Inst Ciencias Espacio IEEC CSIC, E-08193 Bellaterra, Barcelona, Spain, Email: tolos@ice.csic.es |
| 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 |
0375-9474 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000324847700066 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1598 |
| Permanent link to this record |
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| Author |
Dote, A.; Bayar, M.; Xiao, C.W.; Hyodo, T.; Oka, M.; Oset, E. |
| Title |
A narrow quasi-bound state of the DNN system |
Type |
Journal Article |
| Year |
2013 |
Publication |
Nuclear Physics A |
Abbreviated Journal |
Nucl. Phys. A |
| Volume |
914 |
Issue |
|
Pages |
499-504 |
| Keywords |
Nuclear system with a D meson; Few-body system; Variational calculation; Faddeev calculation |
| Abstract |
We have investigated a charmed system of DNN (composed of two nucleons and a D meson) by a complementary study with a variational calculation and a Faddeev calculation with fixed-center approximation (Faddeev-FCA). In the present study, we employ a DN potential based on a vector-meson exchange picture in which a resonant A(c)(2595) is dynamically generated as a DN quasi-bound state, similarly to the A(1405) as a (K) over barN one in the strange sector. As a result of the study of variational calculation with an effective DN potential and three kinds of NN potentials, the DNN(J(pi) =0(-), I = 1/2) is found to be a narrow quasi-bound state below A(c)(2595)N threshold: total binding energy similar to 225 MeV and mesonic decay width similar to 25 MeV. On the other hand, the J(pi) =1(-) state is considered to be a scattering state of A(c)(2595) and a nucleon. These results are essentially supported by the Faddeev-FCA calculation. By the analysis of the variational wave function, we have found a unique structure in the DNN(J(pi) = 0, I = 1/2) such that the D meson stays around the center of the total system due to the heaviness of the D meson. |
| Address |
[Dote, A.] High Energy Accelerator Res Org KEK, IPNS, KEK Theory Ctr, Tsukuba, Ibaraki 3050801, Japan, Email: dote@post.kek.jp |
| 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 |
0375-9474 |
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:000324847700071 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1602 |
| Permanent link to this record |
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| |
| Author |
Ramos, A.; Oset, E. |
| Title |
The role of vector-baryon channels and resonances in the gamma p -> K-0 Sigma(+) and gamma n -> K-0 Sigma(0) reactions near the K*Lambda threshold |
Type |
Journal Article |
| Year |
2013 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
727 |
Issue |
1-3 |
Pages |
287-292 |
| Keywords |
|
| Abstract |
We have studied the gamma p -> K-0 Sigma(+) reaction in the energy region around the K*Lambda and K*Sigma thresholds, where the CBELSA/TAPS cross section shows a sudden drop and the differential cross section experiences a transition from a forward-peaked distribution to a flat one. Our coupled-channel model incorporates the dynamics of the vector meson-baryon interaction which is obtained from the hidden gauge formalism. We find that the cross section in this energy region results from a delicate interference between amplitudes having K*Lambda and K*Sigma intermediate states. The sharp downfall is dictated by the presence of a nearby N* resonance produced by our model, a feature that we have employed to predict its properties. We also show results for the complementary gamma n -> K-0 Sigma(0) reaction, the measurement of which would test the mechanism proposed in this work. |
| Address |
[Ramos, A.] Univ Barcelona, Dept Estruct & Constituents Mat, E-08028 Barcelona, Spain, Email: ramos@ecm.ub.edu |
| 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 |
|
Medium |
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| Area |
|
Expedition |
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Conference |
|
| Notes |
WOS:000328518400041 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
1681 |
| Permanent link to this record |
