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n_TOF Collaboration(Paradela, C. et al), Domingo-Pardo, C., Plag, R., Plompen, A., & Tain, J. L. (2011). (237)Np(n,f) Cross Section: New Data and Present Status. J. Korean Phys. Soc., 59(2), 1908–1911.
Abstract: In this document, we present the final result obtained at the nTOF experiment; for the neutron-induced fission cross section of the (237)Np, from the fission threshold up to 1 GeV. The method applied to get tins result is briefly discussed. nTOF data are compared to the last experimental measurements using other TOF facilities or the surrogate method, reported experiments performed with monoenergetic sources and the FISCAL systematic, including a discussion about the existing discrepancies.
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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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Pasqualato, G. et al, Gadea, A., & Jurado, M. (2023). An alternative viewpoint on the nuclear structure towards 100Sn: Lifetime measurements in 105Sn. Phys. Lett. B, 845, 138148–7pp.
Abstract: This work aims at presenting an alternative approach to the long standing problem of the B(E2) values in Sn isotopes in the vicinity of the N=Z double-magic nucleus Sn-100, until now predominantly measured with relativistic and intermediate-energy Coulomb excitation reactions. The direct measurement of the lifetime of low-lying excited states in odd-even Sn isotopes provides a new and precise guidance for the theoretical description of the nuclear structure in this region. Lifetime measurements have been performed in Sn-105 for the first time with the coincidence Recoil Distance Doppler Shift technique. The lifetime results for the 7/2(1)(+) first excited state and the 11/2(1)(+) state, 2(+)(Sn-104) circle times nu 1g(7/2) multiplet member, are discussed in comparison with state-of-the-art shell model and mean field calculations, highlighting the crucial contribution of proton excitation across the core of Sn-100. The reduced transition probability B(E2) of the 11/2(1)(+) core-coupled state points out an enhanced staggering with respect to the B(E2; 2(1)(+) -> 0(1)(+)) in the even-mass Sn-104 and Sn-106 isotopes.
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Garcia Canal, C. A., Tarutina, T., & Vento, V. (2023). Analysis of Nuclear Effects in Structure Functions and Their Connection with the Binding Energy of Nuclei. Braz. J. Phys., 53(6), 161–8pp.
Abstract: We describe nuclear effects in structure functions of nuclei in DIS by means of a multiplicative factor beta(A)(x) which differentiates the structure function of the bound nucleons from that of the free nucleons. Our analysis determines that beta(A)(x) establishes a relation between the quark-gluon dynamics expressed by the bound nucleon structure functions and the nuclear dynamics as described by the well-known semi-empirical Bethe-Weizsacker mass formula. This relation corroborates a connection between the underlying quark-gluon dynamics and the phenomenological nuclear dynamics.
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IDS Collaboration(Lica, R. et al), & Morales, A. I. (2017). beta decay studies of n-rich Cs isotopes with the ISOLDE Decay Station. J. Phys. G, 44(5), 054002–14pp.
Abstract: Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd-A neutron-rich members of this isotopic chain show typical patterns related to non-axially symmetric shapes, which are however less marked compared to even-A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on Cs148-150 beta-decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of Ba-149 is presented, giving a first insight in the structure of this neutron-rich nucleus.
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Tain, J. L. et al, Algora, A., Estevez, E., Rubio, B., Valencia, E., & Jordan, D. (2011). Beta Decay Studies of Neutron Rich Nuclei Using Total Absorption Gamma-ray Spectroscopy and Delayed Neutron Measurements. J. Korean Phys. Soc., 59(2), 1499–1502.
Abstract: A complete characterisation of the beta-decay of neutron-rich nuclei can be obtained from the measurement of beta-delayed gamma rays and, whenever the process is energetically possible, beta-delayed neutrons. The accurate determination of the beta-intensity distribution and the beta-delayed neutron emission probability is of great relevance in the fields of reactor technology and nuclear astrophysics. A programme for combined measurements using the total absorption gamma-ray spectroscopy technique and both neutron counters and neutron time-of-flight spectrometers is presented.
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Rubio, B., Gelletly, W., Algora, A., Nacher, E., & Tain, J. L. (2017). Beta decay studies with total absorption spectroscopy and the Lucrecia spectrometer at ISOLDE. J. Phys. G, 44(8), 084004–25pp.
Abstract: Here we present the experimental activities carried out at ISOLDE with the total absorption spectrometer Lucrecia, a large 4 pi scintillator detector designed to absorb a full gamma cascade following beta decay. This spectrometer is designed to measure beta-feeding to excited states without the systematic error called Pandemonium. The set up allows the measurement of decays of very short half life. Experimental results from several campaigns, that focus on the determination of the shapes of beta-decaying nuclei by measuring their beta decay strength distributions as a function of excitation energy in the daughter nucleus, are presented.
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Lauritsen, T. et al, & Perez-Vidal, R. M. (2016). Characterization of a gamma-ray tracking array: A comparison of GRETINA and Gammasphere using a Co-60 source. Nucl. Instrum. Methods Phys. Res. A, 836, 46–56.
Abstract: In this paper; we provide a formalism for the characterization of tracking arrays with emphasis on the proper corrections required to extract their photopeak efficiencies and peak-to-total ratios. The methods are first applied to Gammasphere, a well characterized 4 pi array based on the principle of Compton suppression, and subsequently to GRETINA. The tracking efficiencies are then discussed and some guidelines as to what clustering angle to use in the tracking algorithm are presented. It was possible, using GEANT4 simulations, to scale the measured efficiencies up to the expected values for the full 4 pi implementation of GRETA.
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n_TOF Collaboration(Guerrero, C. et al), Giubrone, G., & Tain, J. L. (2011). Characterization of the New n_TOF Neutron Beam: Fluence, Profile and Resolution. J. Korean Phys. Soc., 59(2), 1624–1627.
Abstract: After a halt of four years, the nTOF spallation neutron facility at CERN has resumed operation in November 2008 with a new spallation target characterized by an improved safety and engineering design, resulting in a more robust overall performance and efficient cooling. The first measurement during the 2009 run has aimed at the full characterization of the neutron beam. Several detectors, such as calibrated fission chambers, the nTOF Silicon Monitor, a MicroMegas detector with (10)B and (235)U samples, as well as liquid and solid scintillators have been used in order to characterize the properties of the neutron fluence. The spatial profile of the beam has been studied with a specially designed “X-Y” MicroMegas which provided a 2D image of the beam as a function of neutron energy. Both properties have been compared with simulations performed. with the FLUKA code. The characterization of the resolution function is based on results from simulations which have been verified by the study of narrow capture resonances. of (56)Fe, which were measured as part of a new campaign of (n,gamma) measurements on Fe and Ni isotopes.
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Ralet, D. et al, Gadea, A., & Perez, R. M. (2019). Evidence of octupole-phonons at high spin in Pb-207<bold> </bold>. Phys. Lett. B, 797, 134797–6pp.
Abstract: A lifetime measurement of the 19/2(-) state in Pb-207 has been performed using the Recoil Distance Doppler-Shift (RDDS) method. The nuclei of interest were produced in multi-nucleon transfer reactions induced by a Pb-208 beam impinging on a Mo-100 enriched target. The beam-like nuclei were detected<bold> </bold>and identified in terms of their atomic mass number in the VAMOS++ spectrometer while the prompt gamma rays were detected by the AGATA tracking array. The measured large reduced transition probability B(E3, 19/2(-) -> 13/2(+)) = 40(8) W.u. is the first indication of the octupole phonon at high spin in Pb-207. An analysis in terms of a particle-octupole-vibration coupling model indicates that the measured B(E3) value in Pb-207 is compatible with the contributions from single-phonon and single particle E3 as well as E3 strength arising from the double-octupole-phonon 6(+) state, all adding coherently. A crucial aspect of the coupling model, namely the strong mixing between single-hole and the phonon-hole states, is confirmed in a realistic shell-model calculation.
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