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Kulikov, I., Algora, A., Atanasov, D., Ascher, P., Blaum, K., Cakirli, R. B., et al. (2020). Masses of short-lived Sc-49, Sc-50, As-70, Br-73 and stable Hg-196 nuclides. Nucl. Phys. A, 1002, 121990–15pp.
Abstract: Mass measurements of Sc-49,Sc-50, As-70, Br-73 and Hg-196 nuclides produced at CERN's radioactive-ion beam facility ISOLDE are presented. The measurements were performed at the ISOLTRAP mass spectrometer by use of the multi-reflection time-of-flight and the Penning-trap mass spectrometry techniques. The new results agree well with previously known literature values. The mass accuracy for all cases has been improved.
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Dote, A., Bayar, M., Xiao, C. W., Hyodo, T., Oka, M., & Oset, E. (2013). A narrow quasi-bound state of the DNN system. Nucl. Phys. A, 914, 499–504.
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.
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Romanets, O., Tolos, L., Garcia-Recio, C., Nieves, J., Salcedo, L. L., & Timmermans, R. (2013). Heavy-quark spin symmetry for charmed and strange baryon resonances. Nucl. Phys. A, 914, 488–493.
Abstract: We study charmed and strange odd-parity baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channels model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral Lagrangian to SU(8) spin-flavor symmetry plus a suitable symmetry breaking. The model generates resonances with negative parity from the s-wave interaction of pseudoscalar and vector mesons with 1/2(+) and 3/2(+) baryons in all the isospin, spin, and strange sectors with one, two, and three charm units. Some of our results can be identified with experimental data from several facilities, such as the CLEO, Belle, or BaBar Collaborations, as well as with other theoretical models, whereas others do not have a straightforward identification and require the compilation of more data and also a refinement of the model. (c) 2013 Elsevier B.V. All rights reserved.
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Hidalgo-Duque, C., Nieves, J., & Pavon Valderrama, M. (2013). Heavy quark spin symmetry and SU(3)-flavour partners of the X (3872). Nucl. Phys. A, 914, 482–487.
Abstract: In this work, an Effective Field Theory (EFT) incorporating light SU(3)-flavour and heavy quark spin symmetries is used to describe charmed meson-antimeson bound states. At Lowest Order (LO), this means that only contact range interactions among the heavy meson and antimeson fields are involved. Besides, the isospin violating decays of the X(3872) will be used to constrain the interaction between the D and a (D) over bar* mesons in the isovector channel. Finally, assuming that the X(3915) and Y(4140) resonances are D* (D) over bar* and D-s* (D) over bar (s)* molecular states, we can determine the four Low Energy Constants (LECs) of the EFT that appear at LO and, therefore, the full spectrum of molecular states with isospin I = 0, 1/2 and 1.
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Vijande, J., Valcarce, A., Carames, T. F., & Garcilazo, H. (2013). Heavy hadron spectroscopy: A quark model perspective. Nucl. Phys. A, 914, 472–481.
Abstract: We present recent results of hadron spectroscopy and hadron-hadron interaction from the perspective of constituent quark models. We pay special attention to the role played by higher order Fock space components in the hadron spectra and the connection of this extension with the hadron-hadron interaction. The main goal of our description is to obtain a coherent understanding of the low-energy hadron phenomenology without enforcing any particular model, to constrain its characteristics and learn about low-energy realization of the theory.
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Tolos, L., Cabrera, D., Garcia-Recio, C., Molina, R., Nieves, J., Oset, E., et al. (2013). Strangeness and charm in nuclear matter. Nucl. Phys. A, 914, 461–471.
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.
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Oset, E., Chen, H. X., Feijoo, A., Geng, L. S., Liang, W. H., Li, D. M., et al. (2016). Study of reactions disclosing hidden charm pentaquarks with or without strangeness. Nucl. Phys. A, 954, 371–392.
Abstract: We present results for five reactions, Lambda(b) -> J/psi K(-)p, Lambda(b) -> J/psi eta Lambda, Lambda(b) -> J/psi pi(-)p, Lambda(b) -> J/psi K-0 Lambda and Xi(-)(b) -> J/psi K-Lambda, where combining information from the meson baryon interaction, using the chiral unitary approach, and predictions made for molecular states of hidden charm, with or without strangeness, we can evaluate invariant mass distributions for the light meson baryon states, and for those of J/psi p or J/psi Lambda. We show that with the present available information, in all of these reactions one finds peaks where the pentaquark states show up. In the Lambda(b) -> J/psi K(-)p, and Lambda(b) -> J/psi pi(-)p reactions we show that the results obtained from our study are compatible with present experimental observations.
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Bayar, M., & Oset, E. (2013). The (K)over-barNN system revisited including absorption. Nucl. Phys. A, 914, 349–353.
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.
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PANDA Collaboration(Singh, B. et al), & Diaz, J. (2016). Study of doubly strange systems using stored antiprotons. Nucl. Phys. A, 954, 323–340.
Abstract: Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the PANDA experiment at FAIR. For the first time, high resolution gamma-spectroscopy of doubly strange Lambda Lambda-hypernuclei will be performed, thus complementing measurements of ground state decays of Lambda Lambda-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Xi(-) -atoms will be feasible and even the production of Omega(-) -atoms will be within reach. The latter might open the door to the vertical bar S vertical bar = 3 world in strangeness nuclear physics, by the study of the hadronic Omega(-) -nucleus interaction. For the first time it will be possible to study the behavior of Xi(+) in nuclear systems under well controlled conditions.
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Martinez Torres, A., Khemchandani, K. P., Jido, D., Kanada-En'yo, Y., & Oset, E. (2013). Three-body hadron systems with strangeness. Nucl. Phys. A, 914, 280–288.
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).
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