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Author Martinez Torres, A.; Khemchandani, K.P.; Oset, E.
Title Theoretical study of the gamma d -> pi(0)eta d reaction Type Journal Article
Year 2023 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 107 Issue 2 Pages 025202 - 24pp
Keywords
Abstract (down) We have done a theoretical study of the gamma d -> pi(0)eta d reaction starting with a realistic model for the gamma N -> pi(0)eta N reaction that reproduces cross sections and polarization observables at low energies and involves the gamma N -> Delta(1700) -> eta Delta(1232) -> eta pi N-0 process. For the coherent reaction in the deuteron we considered the impulse approximation together with the rescattering of the pions and the eta on a different nucleon than the one where they are produced. We found this second mechanism very important since it helps share between two nucleons the otherwise large momentum transfer of the reaction. Other contributions to the gamma d -> pi(0)eta d reaction, involving the gamma N -> pi(+/-)pi N-0' process, followed by the rescattering of the pi(+/-) with another nucleon to give eta and a nucleon, have also been included. We find a natural explanation, tied to the dynamics of our model, for the shift of the eta-d mass distribution to lower invariant masses, and of the pi(0)-d mass distribution to larger invariant masses, compared to a phase space calculation. We also study theoretical uncertainties related to the large momenta of the deuteron wave function involved in the process as well as to the couplings present in the model. Striking differences are found with the experimental angular distribution and further theoretical investigations might be necessary.
Address [Torres, A. Martinez] Univ Sao Paulo, Inst Fis, BR-05389970 Sao Paulo, Brazil, Email: amartine@if.usp.br;
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 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000981821500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5563
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Author Martinez Torres, A.; Bayar, M.; Jido, D.; Oset, E.
Title Strategy to find the two Lambda (1405) states from lattice QCD simulations Type Journal Article
Year 2012 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 86 Issue 5 Pages 055201 - 13pp
Keywords
Abstract (down) 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
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Author Martinez Torres, A.; Garzon, E.J.; Oset, E.; Dai, L.R.
Title Limits to the fixed center approximation to Faddeev equations: The case of the phi(2170) Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 11 Pages 116002 - 9pp
Keywords
Abstract (down) The fixed center approximation to the Faddeev equations has been used lately with success in the study of bound systems of three hadrons. It is also important to set the limits of the approach in those problems to prevent proliferation of inaccurate predictions. In this paper, we study the case of the phi(2170), which has been described by means of Faddeev equations as a resonant state of phi and K (K) over bar, and show the problems derived from the use of the fixed center approximation in its study. At the same time, we also expose the limitations of an alternative approach recently proposed.
Address [Martinez Torres, A.] 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000291151000015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 637
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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 (down) 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 Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0375-9474 ISBN Medium
Area Expedition Conference
Notes WOS:000324847700036 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1596
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Author Malabarba, B.B.; Khemchandani, K.P.; Martinez Torres, A.; Oset, E.
Title D1(2420) and its interactions with a kaon: Open charm states with strangeness Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 107 Issue 3 Pages 036016 - 12pp
Keywords
Abstract (down) In this work we present an attempt to describe the X1(2900) found by the LHCb collaboration, in the experimental data on the invariant mass spectrum of D-K+, as a three-meson molecular state of the KpD over line system. We discuss that the interactions in all the subsystems are attractive in nature, with the pD over line interaction generating over line D1(2420) and the Kp resonating as K1(1270). We find that the system can form a three-body state but with a mass higher than that of X1(2900). We investigate the KpD system too, finding that the three-body dynamics generates an isoscalar state, which can be related to D*s1(2860), and an exotic isovector state. This latter state has a mass similar to that of the X0(2900) and X1(2900) states found by LHCb, but a very small width (similar to 7.4 +/- 0.9 MeV) and necessarily requires more than two quarks to describe its properties. We hope that our findings will encourage experimental investigations of the isovector KpD state. Finally, in the pursuit of finding a description for X1(2900), we study the K over line K*D* system where over line K*D* forms 0+, 1+, and 2+ states. We do not find a state that can be associated with X1(2900).
Address [Malabarba, Brenda B.; Torres, A. Martinez] Univ Sao Paulo, Inst Fis, BR-05389970 Sao Paulo, Brazil, Email: brenda@if.usp.br;
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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000989327600013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5562
Permanent link to this record