Records |
Author |
Doring, M.; Oset, E.; Meissner, U.G. |
Title |
Evaluation of the polarization observables I-S and I-C in the reaction gamma p -> pi(0)eta p |
Type |
Journal Article |
Year |
2010 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
Volume |
46 |
Issue |
2 |
Pages |
315-323 |
Keywords |
|
Abstract |
We evaluate the polarization observables I-S and I-C for the reaction gamma p -> pi(0)eta p, using a chiral unitary framework developed earlier. The I-S and I-C observables have been recently measured for the first time by the CBELSA/TAPS Collaboration. The theoretical predictions of I-S and I-C, given for altogether 18 angle-dependent functions, are in good agreement with the measurements. Also, the asymmetry d Sigma/dcos theta evaluated here agrees with the data. We show the importance of the Delta(1700) D-33-resonance and its S-wave decay into eta Delta(1232). The result can be considered as a further confirmation of the dynamical nature of this resonance. At the highest energies, deviations of the predictions from the data start to become noticeable, which leaves room for additional processes and resonances such as a Delta(1940) D-33. We also point out how to further improve the calculation. |
Address |
[Doering, M.; Meissner, U. -G.] Forschungszentrum Julich, Inst Kernphys, D-52425 Julich, Germany, Email: m.doering@fz-juelich.de |
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 |
ISI:000284869600016 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
314 |
Permanent link to this record |
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Author |
Tolos, L.; Molina, R.; Oset, E.; Ramos, A. |
Title |
(K)over-bar* mesons in dense matter |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
82 |
Issue |
4 |
Pages |
045210 - 12pp |
Keywords |
|
Abstract |
We study the properties of (K) over bar* mesons in nuclear matter using a unitary approach in coupled channels within the framework of the local hidden gauge formalism and incorporating the (K) over bar pi decay channel in matter. The in-medium (K) over bar *N interaction accounts for Pauli blocking effects and incorporates the (K) over bar* self-energy in a self-consistent manner. We also obtain the (K) over bar* (off-shell) spectral function and analyze its behavior at finite density and momentum. At a normal nuclear matter density, the (K) over bar* meson feels a moderately attractive potential, while the (K) over bar* width becomes five times larger than in free space. We estimate the transparency ratio of the gamma A -> K+K*(-) A` reaction, which we propose as a feasible scenario at the present facilities to detect changes in the properties of the (K) over bar* meson in nuclear medium. |
Address |
[Tolos, L.] Univ Groningen, Theory Grp KVI, NL-9747 AA Groningen, Netherlands, Email: tolos@kvi.nl |
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 |
0556-2813 |
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:000283648400011 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
335 |
Permanent link to this record |
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Author |
Doring, M.; Jido, D.; Oset, E. |
Title |
Helicity amplitudes of the Lambda(1670) and two Lambda(1405) as dynamically generated resonances |
Type |
Journal Article |
Year |
2010 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
Volume |
45 |
Issue |
3 |
Pages |
319-333 |
Keywords |
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Abstract |
We determine the helicity amplitudes A(1/2) and radiative decay widths in the transition Lambda(1670) -> gamma Y (Y = Lambda or Sigma(0)). The Lambda(1670) is treated as a dynamically generated resonance in meson-baryon chiral dynamics. We obtain the radiative decay widths of the Lambda(1670) to gamma Lambda as 2 +/- 1 keV and to -gamma Sigma(0) as 120 +/- 50 keV. Also, the Q(2)-dependence of the helicity amplitudes A(1/2) is calculated. We find that the K Xi component in the Lambda(1670) structure, mainly responsible for the dynamical generation of this resonance, is also responsible for the significant suppression of the decay ratio Gamma(gamma A)/Gamma(gamma Sigma 0). A measurement of the ratio would, thus, provide direct access to the nature of the Lambda(1670). To compare the result for the Lambda(1670), we calculate the helicity amplitudes Lambda(1/2) for the two states of the Lambda(1405). Also, the analytic continuation of Feynman parameterized integrals of more complicated loop amplitudes to the complex plane is developed which allows for an internally consistent evaluation of A(1/2). |
Address |
[Doering, M.] Forschungszentrum Julich, Inst Kernphys, D-52425 Julich, Germany, Email: m.doering@fz-jueiich.de |
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 |
ISI:000281972900006 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
372 |
Permanent link to this record |
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Author |
Molina, R.; Branz, T.; Oset, E. |
Title |
New interpretation for the D*(s2)(2573) and the prediction of novel exotic charmed mesons |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
82 |
Issue |
1 |
Pages |
014010 - 17pp |
Keywords |
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Abstract |
In this manuscript we study the vector-vector interaction within the hidden-gauge formalism in a coupled channel unitary approach. In the sector C = 1, S = 1, J = 2 we get a pole in the T matrix around 2572 MeV that we identify with the D*(s2)(2573), coupling strongly to the D*K*(D-s(*)phi(omega)) channels. In addition we obtain resonances in other exotic sectors which have not been studied before such as C = 1, S = -1, C = 2, S = 0 and C = 2, S = 1. These "flavor-exotic'' states are interpreted as D*(K) over bar*, D*D*, and (DsD)-D-** molecular states but have not been observed yet. In total we obtain nine states with different spin, isospin, charm, and strangeness of non-C = 0, S = 0 and C = 1, S = 0 character, which have been reported before. |
Address |
[Molina, R.; Oset, E.] Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, Inst Invest Paterna, 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 |
ISI:000280175300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
406 |
Permanent link to this record |
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Author |
Magas, V.K.; Yamagata-Sekihara, J.; Hirenzaki, S.; Oset, E.; Ramos, A. |
Title |
Proton emission off nuclei induced by kaons in flight |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
81 |
Issue |
2 |
Pages |
024609 - 10pp |
Keywords |
|
Abstract |
We study the (K-, p) reaction on nuclei with a 1 GeV/c momentum kaon beam, paying special attention to the region of emitted protons having kinetic energy above 600 MeV, which was used to claim a deeply attractive kaon nucleus optical potential. Our model describes the nuclear reaction in the framework of a local density approach and the calculations are performed following two different procedures: one is based on a many-body method using the Lindhard function and the other is based on a Monte Carlo simulation. The simulation method offers flexibility to account for processes other than kaon quasielastic scattering, such as K- absorption by one and two nucleons, producing hyperons, and allows consideration of final-state interactions of the K-, the p, and all other primary and secondary particles on their way out of the nucleus, as well as the weak decay of the produced hyperons into pi N. We find a limited sensitivity of the cross section to the strength of the kaon optical potential. We also show a serious drawback in the experimental setup-the requirement for having, together with the energetic proton, at least one charged particle detected in the decay counter surrounding the target-as we find that the shape of the original cross section is appreciably distorted, to the point of invalidating the claims made in the experimental paper on the strength of the kaon nucleus optical. |
Address |
[Magas, V. K.; Ramos, A.] Univ Barcelona, Dept Estructura & Constituents Mat, E-08028 Barcelona, Spain, Email: vladimir@ecm.ub.es |
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 |
0556-2813 |
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:000278341300014 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
432 |
Permanent link to this record |