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Author Martinez Torres, A.; Oset, E. url  doi
openurl 
  Title The gamma d -> K(+)K(-)np reaction and an alternative explanation for the “Theta(+)(1540) pentaquark” peak Type Journal Article
  Year 2010 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 81 Issue 5 Pages 055202 - 16pp  
  Keywords  
  Abstract We present a calculation of the gamma d -> K(+)K(-)np reaction with the aim of seeing whether the experimental peak observed in the K(+)n invariant mass around 1526 MeV, from where evidence for the existence of the Theta(+) has been claimed, can be obtained without this resonance as a consequence of the particular dynamics of the process and the cuts applied in the experimental setup. We find that a combination of facts leads indeed to a peak around 1530 MeV for the invariant mass of K(+)n without the need to invoke any new resonance around this energy. This, together with statistical fluctuations that we prove to be large with the statistics of the experiment, is likely to produce the narrower peak observed there.  
  Address [Martinez Torres, A.] Univ Politecn Valencia, CSIC, Ctr Mixto, Dept Fis Teor, E-46071 Valencia, Spain, Email: amartine@ific.uv.es  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000278144800057 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 443  
Permanent link to this record
 

 
Author Xie, J.J.; Martinez Torres, A.; Oset, E. url  doi
openurl 
  Title Faddeev fixed-center approximation to the N K K(bar) system and the signature of a N*(1920)(1/2+) state Type Journal Article
  Year 2011 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 83 Issue 6 Pages 065207 - 8pp  
  Keywords  
  Abstract We perform a calculation for the three-body N (K) over barK scattering amplitude by using the fixed-center approximation to the Faddeev equations, taking the interaction between N and (K) over bar, N and K, and (K) over bar and K from the chiral unitary approach. The resonant structures show up in the modulus squared of the three-body scattering amplitude and suggest that a N (K) over barK hadron state can be formed. Our results are in agreement with others obtained in previous theoretical works, which claim a new N* resonance around 1920 MeV with spin-parity J(P) = 1/2(+). The existence of these previous works allows us to test the accuracy of the fixed center approximation in the present problem and sets the grounds for possible application in similar problems, as an explorative tool to determine bound or quasibound three-hadron systems.  
  Address [Xie, Ju-Jun; Oset, E.] Univ Valencia, Ctr Mixto CSIC, Inst Fis Corpuscular IFIC, Inst Invest Paterna, E-46071 Valencia, Spain, Email: xiejujun@ific.uv.es  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000291984800004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 665  
Permanent link to this record
 

 
Author Bayar, M.; Yamagata-Sekihara, J.; Oset, E. url  doi
openurl 
  Title K-bar NN system with chiral dynamics Type Journal Article
  Year 2011 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 84 Issue 1 Pages 015209 - 9pp  
  Keywords  
  Abstract We have performed a calculation of the scattering amplitude for the three-body system (K) over bar NN assuming (K) over bar scattering against a NN cluster using the fixed center approximation to the Faddeev equations. The (K) over bar N amplitudes, which we take from chiral unitary dynamics, govern the reaction and we find a (K) over bar NN amplitude that peaks around 40 MeV below the (K) over bar NN threshold, with a width in |T|(2) of the order of 50 MeV for spin 0 and has another peak around 27 MeV with similar width for spin 1. The results are in line with those obtained using different methods but implementing chiral dynamics. The simplicity of the approach allows one to see the important ingredients responsible for the results. In particular, we show the effects from the reduction of the size of the NN cluster due to the interaction with the (K) over bar and those from the explicit consideration of the pi Sigma N channel in the three-body equations.  
  Address [Bayar, M; Yamagata-Sekihara, J; Oset, E] Inst Invest Paterna, Inst Fis Corpuscular, Ctr Mixto CSIC UV, E-46071 Valencia, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000292825800007 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 686  
Permanent link to this record
 

 
Author Wu, J.J.; Molina, R.; Oset, E.; Zou, B.S. url  doi
openurl 
  Title Dynamically generated N* and Lambda* resonances in the hidden charm sector around 4.3 GeV Type Journal Article
  Year 2011 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 84 Issue 1 Pages 015202 - 15pp  
  Keywords  
  Abstract The interactions of (D) over bar Sigma(c)-(D) over bar Lambda(c), (D) over bar*Sigma(c)-(D) over bar*Lambda(c), and related strangeness channels, are studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. A series of meson-baryon dynamically generated relatively narrow N* and Lambda* resonances are predicted around 4.3 GeV in the hidden charm sector. We make estimates of production cross sections of these predicted resonances in (p) over barp collisions for the experiment of antiproton annihilation at Darmstadt (PANDA) at the forthcoming GSI Facility for Antiproton and Ion Research (FAIR) facility.  
  Address [Wu, JJ; Zou, BS] CAS, Inst High Energy Phys, Beijing 100049, Peoples R China  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000292513200008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 689  
Permanent link to this record
 

 
Author Xie, J.J.; Chen, H.X.; Oset, E. url  doi
openurl 
  Title The pp -> p Lambda K(+) and pp -> p Sigma(0)K(+) reactions with chiral dynamics Type Journal Article
  Year 2011 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 84 Issue 3 Pages 034004 - 8pp  
  Keywords  
  Abstract We report on a theoretical study of the pp -> p Lambda K(+) and pp -> p Sigma(0)K(+) reactions near threshold using a chiral dynamical approach. The production process is described by single-pion and single-kaon exchange. The final state interactions of nucleon-hyperon, K-hyperon, and K-nucleon systems are also taken into account. We show that our model leads to a fair description of the experimental data on the total cross section of the pp -> p Lambda K(+) and pp -> p Sigma(0)K(+) reactions. We find that the experimental observed strong suppression of Sigma(0) production compared to Lambda production at the same excess energy can be explained. However, ignorance of phases between some amplitudes does not allow one to properly account for the nucleon-hyperon final state interaction for the pp -> p Sigma(0)K(+) reaction. We also demonstrate that the invariant mass distribution and the Dalitz plot provide direct information about the Lambda and Sigma(0) production mechanisms and may be tested by experiments at COSY or HIRFL-CSR.  
  Address [Xie, JJ; Chen, HX; Oset, E] Univ Valencia, Inst Fis Corpuscular IFIC, Ctr Mixto CSIC, Inst Invest Paterna, E-46071 Valencia, Spain, Email: xiejujun@ific.uv.es  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000294925700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 757  
Permanent link to this record
 

 
Author Molina, R.; Xiao, C.W.; Oset, E. url  doi
openurl 
  Title J/psi reaction mechanisms and suppression in the nuclear medium Type Journal Article
  Year 2012 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 86 Issue 1 Pages 014604 - 9pp  
  Keywords  
  Abstract Recent studies of the interaction of vector mesons with nuclei make possible and opportune the study of the interaction of the J/psi with nuclei and the investigation of the origin of the J/psi suppression in its propagation thorough a nuclear medium. We observe that the transition of J/psi N to VN with V being a light vector, rho, omega, phi, together with the inelastic channels, J/psi N -> (D) over bar Lambda(c) and J/psi N -> (D) over bar Sigma(c), leads to a particular shape of the inelastic cross section. Analogously, we consider the mechanisms where the exchanged D collides with a nucleon and gives pi Lambda(c) or pi Sigma(c). The cross section has a peak around root s = 4415 MeV, where the J/psi N couples to a resonance predicted recently. We study the transparency ratio for electron-induced J/psi production in nuclei at about 10 GeV and find that 30-35% of the J/psi produced in heavy nuclei are absorbed inside the nucleus. This ratio is in line with depletions of J/psi through matter observed in other reactions.  
  Address [Molina, R.] Univ Valencia, CSIC, Ctr Mixto, Inst Invest Paterna,Dept Fis Teor, Valencia 46071, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000306191500005 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1100  
Permanent link to this record
 

 
Author Bayar, M.; Xiao, C.W.; Hyodo, T.; Dote, A.; Oka, M.; Oset, E. url  doi
openurl 
  Title Energy and width of a narrow I=1/2 DNN quasibound state Type Journal Article
  Year 2012 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 86 Issue 4 Pages 044004 - 16pp  
  Keywords  
  Abstract The energies and widths of DNN quasibound states with isospin I = 1/2 are evaluated in two methods, the fixed center approximation to the Faddeev equation and the variational method approach to the effective one-channel Hamiltonian. The DN interactions are constructed so they dynamically generate the Lambda(c)(2595) (I = 0, J(pi) = 1/2(-)) resonance state. We find that the system is bound by about 250 MeV from the DNN threshold, root s similar to 3500 MeV. Its width, including both the mesonic decay and the D absorption, is estimated to be about 20-40 MeV. The I = 0 DN pair in the DNN system is found to form a cluster that is similar to the Lambda(c)(2595).  
  Address [Bayar, M.; Xiao, C. W.; Oset, E.] Ctr Mixto Univ Valencia CSIC, Inst Invest Paterna, Dept Fis Teor, Valencia 46071, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000310436100003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1197  
Permanent link to this record
 

 
Author Martinez Torres, A.; Bayar, M.; Jido, D.; Oset, E. url  doi
openurl 
  Title Strategy to find the two Lambda (1405) states from lattice QCD simulations Type Journal Article
  Year 2012 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 86 Issue 5 Pages 055201 - 13pp  
  Keywords  
  Abstract Theoretical studies within the chiral unitary approach, and recent experiments, have provided evidence of the existence of two isoscalar states in the region of the Lambda(1405). In this paper we use the same chiral approach to generate energy levels in a finite box. In a second step, assuming that these energies correspond to lattice QCD results, we devise the best strategy of analysis to obtain the two states in the infinite-volume case, with sufficient precision to distinguish them. We find out that by using energy levels obtained with asymmetric boxes and/or with a moving frame, with reasonable errors in the energies, one has a successful scheme to get the two Lambda(1405) poles.  
  Address [Torres, A. Martinez; Jido, D.] Kyoto Univ, Yukawa Inst Theoret Phys, Kyoto 6068502, Japan  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000310685400008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1226  
Permanent link to this record
 

 
Author Roca, L.; Oset, E. url  doi
openurl 
  Title Lambda(1405) poles obtained from pi(0)Sigma(0) photoproduction data Type Journal Article
  Year 2013 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 87 Issue 5 Pages 055201 - 8pp  
  Keywords  
  Abstract We present a strategy to extract the position of the two Lambda(1405) poles from experimental photoproduction data measured recently at different energies in the gamma p -> K+pi(0)Sigma(0) reaction at Jefferson Laboratory. By means of a chiral dynamics motivated potential with free parameters, we solve the Bethe-Salpeter equation in the coupled channels (K) over barN and pi Sigma in isospin I = 0 and parametrize the amplitude for the photonuclear reaction in terms of a linear combination of the pi Sigma -> pi Sigma and (K) over barN -> pi Sigma scattering amplitudes in I = 0, with a different linear combination for each energy. Good fits to the data are obtained with some sets of parameters, by means of which one can also predict the cross section for the K- p -> pi(0)Sigma(0) reaction. These later results help us decide among the possible solutions. The result is that the different solutions lead to two poles similar to those found in the chiral unitary approach. With the best result we find the two Lambda(1405) poles at 1385 – 68i MeV and 1419 – 22i MeV.  
  Address Univ Murcia, Dept Fis, E-30100 Murcia, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000318527400004 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1442  
Permanent link to this record
 

 
Author Garzon, E.J.; Xie, J.J.; Oset, E. url  doi
openurl 
  Title Case in favor of the N*(1700)(3/2(-)) Type Journal Article
  Year 2013 Publication (up) Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 87 Issue 5 Pages 055204 - 12pp  
  Keywords  
  Abstract Using an interaction extracted from the local hidden-gauge Lagrangians, which brings together vector and pseudoscalar mesons, and the coupled channels rho N (s wave), pi N (d wave), pi Delta (s wave), and pi Delta (d wave), we look in the region ofv root s = 1400-1850 MeV and find two resonances dynamically generated by the interaction of these channels, which are naturally associated to N*(1520)(3/2(-)) and N*(1700)(3/2(-)). N*(1700)(3/2(-)) appears neatly as a pole in the complex plane. The free parameters of the theory are chosen to fit the pi N (d-wave) data. Both the real and imaginary parts of the pi N amplitude vanish in our approach in the vicinity of this resonance, which is similar to what happens in experimental determinations and which makes this signal very weak in this channel. This feature could explain why this resonance does not show up in some experimental analyses, but the situation is analogous to that of the f(0)(980) resonance, the second scalar meson after sigma[f(0)(500)] in the pi pi(d-wave) amplitude. The unitary coupled channel approach followed here, in connectionwith the experimental data, leads automatically to a pole in the 1700-MeV region and makes this second 3/2-resonance unavoidable.  
  Address Univ Valencia, CSIC, Inst Invest Paterna, Ctr Mixto,Dept Fis Teor, Valencia 46071, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000319058200003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1455  
Permanent link to this record
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