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Vento, V. (2013). Confinement, the gluon propagator and the interquark potential for heavy mesons. Eur. Phys. J. A, 49(6), 71–7pp.
Abstract: The interquark static potential for heavy mesons described by a massive one-gluon exchange interaction obtained from the propagator of the truncated Dyson-Schwinger equations does not reproduced the expected Cornell potential. I show that no formulation based on a finite propagator will lead to confinement of quenched QCD. I propose a mechanism based on a singular nonperturbative coupling constant which has the virtue of giving rise to a finite gluon propagator and (almost) linear confinement. The mechanism can be slightly modified to produce the screened potentials of unquenched QCD.
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Vento, V. (2016). Glueball-meson mixing. Eur. Phys. J. A, 52(1), 1–5pp.
Abstract: Calculations in unquenched QCD for the scalar glueball spectrum have confirmed previous results of Gluodynamics finding a glueball at similar to 1750 MeV. I analyze the implications of this discovery from the point of view of glueball-meson mixing in light of the experimental scalar sprectrum.
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Vento, V. (2017). AdS gravity and the scalar glueball spectrum. Eur. Phys. J. A, 53(9), 185–4pp.
Abstract: The scalar glueball spectrum has attracted much attention since the formulation of Quantum Chromodynamics. Different approaches give very different results for the glueball masses. We revisit the problem from the perspective of the AdS/CFT correspondence.
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Uchino, T., Liang, W. H., & Oset, E. (2016). Baryon states with hidden charm in the extended local hidden gauge approach. Eur. Phys. J. A, 52(3), 43–16pp.
Abstract: The s-wave interaction of (D) over bar Lambda(c), (D) over bar Sigma(c),(D) over bar*Lambda(c), (D) over bar*Sigma(c) and (D) over bar Sigma(c)*, (D) over bar*Sigma(c)*, is studied within a unitary coupled channels scheme with the extended local hidden gauge approach. In addition to the Weinberg-Tomozawa term, several additional diagrams via the pion exchange are also taken into account as box potentials. Furthermore, in order to implement the full coupled channels calculation, some of the box potentials which mix the vector-baryon and pseudoscalar-baryon sectors are extended to construct the effective transition potentials. As a result, we have observed six possible states in several angular momenta. Four of them correspond to two pairs of admixture states, two of (D) over bar Sigma(c) – (D) over bar*Sigma(c) with J – 1/2, and two of (D) over bar Sigma(c)* – (D) over bar*Sigma(c)* with J = 3/2. Moreover, we find a (D) over bar*Sigma(c) resonance which couples to the (D) over bar Lambda(c) channel and one spin degenerated bound state of (D) over bar*Sigma(c)* with J = 1/2, 5/2.
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Thisse, D. et al, Algora, A., & Guadilla, V. (2023). Study of N=50 gap evolution around Z=32: new structure information for Ge-82. Eur. Phys. J. A, 59(7), 153–13pp.
Abstract: Medium spin states of light N = 50 isotones have been populated using fast neutron-induced fission of Th-232. Online prompt gamma spectroscopy has been performed using the hybrid gamma spectrometer nu-Ball coupled to the LICORNE directional neutron source at the ALTO facility of IJCLab. Medium spin states of the neutron-rich nucleus Ge-82 have been investigated using gamma-gamma and gamma-gamma-gamma coincidence data to exploit the resolving power of nu-Ball. Two new transitions were assigned to this nucleus and a new level was placed in the level scheme. We tentatively assigned to this new state a (7(+)) spin-parity, which is interpreted as a new N = 50 core breaking state. This provides further insight into the energy evolution of the N = 50 shell gap toward Ni-78.
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Testov, D. et al, & Gadea, A. (2019). The 4pi highly-efficient light-charged-particle detector EUCLIDES, installed at the GALILEO array for in-beam gamma-ray spectroscopy. Eur. Phys. J. A, 55(4), 47–8pp.
Abstract: .In a fusion-evaporation reaction, nuclei are produced by evaporating light-charged particles and neutrons from the compound nucleus. Typically, a nucleus of interest is produced as a result of a part of the total cross-section and, in order to guarantee a good channel discrimination, a particle detector, like the EUCLIDES 4 Si-ball array, is necessary. EUCLIDES has been quoted in more than a hundred publications resulting from many experiments performed in combination with the EUROBALL and GASP -ray spectrometers. The present paper reports on the upgraded version of EUCLIDES, that is presently coupled to the new GALILEO -ray spectrometer, installed at the Laboratori Nazionali di Legnaro, INFN. The design, characteristics and performance of the EUCLIDES array are presented and discussed.
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Taprogge, J. et al, Gadea, A., & Montaner-Piza, A. (2016). Proton-hole and core-excited states in the semi-magic nucleus In-131(82). Eur. Phys. J. A, 52(11), 347–10pp.
Abstract: The decay of the N = 83 nucleus Cd-131 has been studied at the RIBF facility at the RIKEN Nishina Center. The main purpose of the study was to identify the position of the and proton-hole states and the energies of core-excited configurations in the semi-magic nucleus In-131. From the radiation emitted following the decay, a level scheme of In-131 was established and the feeding to each excited state determined. Similarities between the single-particle transitions observed in the decays of the N = 83 isotones In-132 and Cd-131 are discussed. Finally the excitation energies of several core-excited configurations in In-131 are compared to QRPA and shell-model calculations.
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Tagliente, G. et al, Babiano-Suarez, V., Domingo-Pardo, C., Ladarescu, I., & Tain, J. L. (2024). High-resolution cross section measurements for neutron interactions on 89Y with incident neutron energies up to 95 keV. Eur. Phys. J. A, 60(1), 21–18pp.
Abstract: The cross section of the Y-89(n,gamma) reaction has important implications in nuclear astrophysics and for advanced nuclear technology. Given its neutron magic number N = 50 and a consequent small neutron capture crosssection,89Y represents one of the key nuclides for the stellars-process. It acts as a bottleneck in the neutron capture chain between the Fe seed and the heavier elements. Moreover, it is located at the overlapping region, where both the weak and mains-process components take place.Y-89, the only stable yttrium isotope, is also used in innovative nuclear reactors. Neutron capture and transmission measurements were per-formed at the time-of-flight facilities n_TOF at CERN and GELINA at JRC-Geel. Resonance parameters of individual resonances were extracted from a resonance analysis of the experimental transmission and capture yields, up to a neutron incident energy of 95 keV. Even though a comparison with results reported in the literature shows differences in resonance parameters, the present data are consistent with the Maxwellian averaged cross section suggested by the astro-physical database KADoNiS.
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Sun, B. X., Chen, H. X., & Oset, E. (2011). rho rho N and rho rho Delta molecules with J(P)=5/2(+) and J(P)=7/2(+). Eur. Phys. J. A, 47(10), 127–8pp.
Abstract: The rho rho N and rho rho Delta three-body systems have been studied within the framework of the fixed center approximation of Faddeev equation. The rho rho interaction in isospin I = 0, spin S = 2 is strongly attractive, and so are the N rho, Delta rho interactions. This leads to bound states of both rho rho N and rho rho Delta. We find peaks of the modulus squared of the scattering matrix around 2227 MeV for rho rho N, and 2372 MeV for rho rho Delta. Yet, the strength of the peak for the rho rho N amplitude is much smaller than for rho rho Delta, weakening the case for a rho rho N bound state, or a dominant rho rho N component. A discussion is made on how these states can be searched for in present programs looking for multimeson final states in different reactions.
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Souza, E. V., Ferreira, M. N., Aguilar, A. C., Papavassiliou, J., Roberts, C. D., & Xu, S. S. (2020). Pseudoscalar glueball mass: a window on three-gluon interactions. Eur. Phys. J. A, 56(1), 25–7pp.
Abstract: In pure-glue QCD, gluon-gluon scattering in the J(PC) = 0(-+) channel is described by a very simple equation, especially if one considers just the leading contribution to the scattering kernel. Of all components in this kernel, only the three-gluon vertex, V-mu nu rho, is poorly constrained by contemporary analyses; hence, calculations of 0(-+) glueball properties serve as a clear window onto the character and form of V-mu nu rho. This is important given that many modern calculations of V-mu nu rho predict the appearance of an infrared suppression in the scalar function which comes to modulate the bare vertex after the nonperturbative resummation of interactions. Such behaviour is a peculiar prediction; but we find that the suppression is essential if one is to achieve agreement with lattice-QCD predictions for the 0(-+) glueball mass. Hence, it is likely that this novel feature of V-mu nu rho is real and has observable implications for the spectrum, decays and interactions of all QCD bound-states.
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