Moderadores
Red FNUC (Red Temática de Física Nuclear)
- Tomás Raúl Rodríguez Frutos (Universidad Complutense de Madrid)
- Cesar Domingo-Pardo (IFIC (CSIC-University of Valencia))
Red FNUC (Red Temática de Física Nuclear)
- Cesar Domingo-Pardo (IFIC (CSIC-University of Valencia))
- Tomás Raúl Rodríguez Frutos (Universidad Complutense de Madrid)
Red FNUC (Red Temática de Física Nuclear)
- Cesar Domingo-Pardo (IFIC (CSIC-University of Valencia))
- Tomás Raúl Rodríguez Frutos (Universidad Complutense de Madrid)
Authors: I. Martel, MJG. Borge, I. Bustinduy, J. Cederkall, T. Kurtukian-Nieto, J. Resta-López, and O. Tengblad, for the ISRS collaboration.
Abstract
The HIE-ISOLDE facility accelerates a unique worldwide variety of radioactive ions up to collision energies close to 10 MeV/A. The physics program covers a broad range of nuclear structure studies, from shell-evolution to nuclear astrophysics....
The study of nuclear reactions involving heavy ions and light targets at low energies provides crucial information for the development and corroboration of different theories and models applied to astrophysical environments. The experimental Basic Nuclear Physics (FNB) line of National Accelerators Center (CNA), is being adapted and prepared with the aim of studding these reactions, taking...
The measurement of neutron capture cross sections provides important nuclear data for the study of astrophysical phenomena, such as the slow neutron capture (s-) process, one of the main mechanisms of nucleosynthesis for isotopes heavier than $^{56}$Fe, which operates in red-giant and massive stars.
Time-of-fight facilities, such as n_TOF, provide point-wise cross sections covering the full...
The production of neutrons through α-induced reactions play an important role in fields such as nuclear astrophysics, underground laboratories, fission and fusion reactors and non-destructive assays for non- proliferation and spent fuel management applications. However, most of the currently available experimental data was measured decades ago, is incomplete and/or present large discrepancies...
Nuclear Physics experiments are usually carried out in large accelerators, whose reduced number restricts the access to these facilities. For this reason, there is a growing interest in developing complementary facilities capable of hosting Nuclear Physics experiments, even at smaller size, to further extend the nuclear data available. In this context, high-power, high-repetition-rate lasers...
The Nuclear Energy Agency (NEA/OECD) included the improvement of the current knowledge on the cross-sections for neutron capture and neutron-induced fission of $^{239}$Pu in its High Priority Request List, motivated by the growing demand for more accurate and reliable nuclear data essential for nuclear applications such as the design and operation of nuclear power plants. To address this need,...
The WASA-FRS HypHI Experiment focuses on the study of light hypernuclei by means of heavy-ion induced reactions. It is part of the WASA-FRS experimental campaign, and so is the Eta-prime Experiment [1]. The distinctive combination of the high-resolution spectrometer FRS [2] and the high-acceptance detector system WASA [3] is used. The experiment was successfully conducted at GSI-FAIR in...
The development of innovative future nuclear reactors and the enhancement of operational safety rely heavily on the precision of nuclear data, particularly in minimizing the uncertainties associated with microscopic neutron-induced cross sections. MYRRHA is an experimental Accelerator Driven System that uses a lead-bismuth mixture as a coolant system. The radiological burden associated with...
Predictions of the spectra of nuclear reactors’ electron antineutrinos do not coincide with the measurements [1]. These differences are known as the “Reactor Antineutrino Anomaly” and the spectral “bump” [2]. The e-shape collaboration looks for solutions for these problems via the improvement of relevant nuclear models used in the calculation of antineutrino spectra from reactors [3]. The...
Neutron emitted in nuclear reactions following the absorption of alpha particles play a key role in several fields of research: acting as neutron source in the s-process, affecting the production of elements in the r-process occurring in the neutron driven winds of core-collapse supernova, inducing background signals in underground dark matter search experiments, or being a proxy for active...
The neutron time-of-flight facility n_TOF at CERN is dedicated to measuring neutron-induced reaction cross-sections of relevance to nuclear technologies, astrophysics, and other scientific applications. The facility uses a high-intensity neutron source, a large lead spallation target coupled with the CERN-PS 20 GeV/c proton beam, and features three experimental areas: Experimental Area 1...
Durante los últimos años hemos desarrollado en la Unidad de Innovación Nuclear del CIEMAT el código NuDEX, el cual sirve para modelar la generación de cascadas de rayos gamma y electrones provenientes de desexcitaciones nucleares.
La forma de operar de NuDEX es muy similar a la de DICEBOX [1] o DEGEN [2]: lo que hace es generar el esquema de niveles completo por debajo del nivel del que parte...
Halo nuclei are a group of nuclei characterized by a low binding energy for their last nucleons, situated in low orbital momentum states and, as a consequence, an unusually large spatial extension that deviates from the standard $r=r_0 A^{1/3}$ relation. The first empirical observation of this behaviour came from experimental measurements of the interaction cross-section for neutron-rich...
Neutron-rich Ca isotopes towards neutron number N = 34 are pivotal for exploring the evolution of the fp-shell orbitals [1]. Beyond the N = 28 shell gap at 48Ca, new magic numbers at N = 32 and 34 were established through spectroscopy of low-lying states [2] and mass measurements [3]. Most recently, the spatial extension of the 1f7/2 and 2p3/2 neutron orbitals was determined via a one-neutron...
Historically, innovations in detection techniques and advances in high-quality pulsed neutron beams have led to fascinating discoveries in stellar nucleosynthesis and subsequent refinements of theoretical models of stellar structure and galactic chemical evolution.
The n_TOF collaboration has been advancing innovative (n,γ) experimental setups aimed at achieving high sensitivity for...
The $^{44}$Ti nucleosynthesis takes place in Core Collapse Supernova (CCSN) explosions, the final process suffered by stars with initial mass greater than 8 M$_\odot$. This, alongside its characteristic gamma decay chain, turns the isotope into a good gamma tracer of Supernovae events. Besides, the comparison between observations and models of the synthesized $^{44}$Ti in CCSN gives important...
Fast-Timing Study of Nuclear Shape Deformation in $^{100}$Sr across N=60
The region around N≈60 with Z≤40 has generated considerable interest as it features the most abrupt shape transition known to date in the nuclear chart, when crossing from N=58 to N=60 [1]. This transition is closely linked to shape coexistence [2], a phenomenon where two or more states with different intrinsic...
Neutron capture cross-section measurements are fundamental in the study of astrophysical phenomena, such as the slow neutron capture (s-) process of nucleosynthesis operating in red-giant and massive stars [1]. Recently, the more exotic i-process, which involves higher neutron densities and more exotic nuclei than the s-process [2], is also gaining great interest.
One of the best suited...
Nuclear structure of exotic nuclei near $^{78}\mathrm{Ni}$, with $Z = 28$ and $N = 50$, is fundamental to understand the doubly magic nature of this neutron-rich nucleus. Currently, many experimental and theoretical efforts are dedicated to investigating this region of the nuclear chart [1-5], aiming to comprehend the robustness of nuclear shells far from stability and the emergence of...
Multimessenger measurements in astrophysics have become a key element in constraining the nuclear equation of state and the characteristics of neutron stars. The stellar characteristics of a neutron star are strongly affected by baryonic interactions. Constraints from experimental observations of heavy ions show remarkable consistency with astrophysical measurements and provide complementary...
Chromium is a very relevant element regarding criticality safety in nuclear reactors because its presence in stainless steel, used as structural material. There are serious discrepancies between the different evaluated data of $^{50}$Cr and $^{53}$Cr neutron capture cross sections which are not present in the corresponding estimated uncertainties. The Nuclear Energy Agency (NEA) opened an...
The complex nature of the nucleon-nucleon interaction allows for spherical, oblate and prolate deformations to appear at similar energies within the same nucleus. This phenomenon, known as shape coexistence, is widespread across the nuclear chart and it provides a crucial role in understanding nuclear structure [1].
In our study we complement shell-model calculations [2] with...
In this work, a temperature-dependent equation of state of nuclear
and hyperonic matter suitable for use in relativistic simulations of neutron
star mergers and supernovae is presented. We investigate the impact of
the uncertainty in the hyperonic sector on the astrophysical observables.
We show that these uncertainties have a significant effect on the global
properties of the stars, such as...
Shape of nuclei is determined by a fine balance between the stabilizing effect of closed shells and the pairing and quadrupole forces that tend to induce deformation [1]. In the mass region around A=100, there exist clear cut examples of the rapid appearance of deformation such as Zr (even-even) [2] and Nb isotopes (odd-even) [3], which can be understood in terms of the coexistence of two...
The r-process, also known as the rapid neutron capture process, plays a crucial role in the formation of more than half of the elements that are heavier than iron. To shed light on this process, the BRIKEN collaboration [1] has conducted extensive measurements of the β-decay properties of important nuclei at the Radioactive Isotope Beam Factory (RIBF) located at the RIKEN Nishina Center in...
The study of reactions involving weakly-bound exotic nuclei is an active field due to advances in radioactive beam facilities. Many of these nuclei can be approximately described by a model consisting of an inert core and one or more valence nucleons. For some of these nuclei, the quadrupole deformation is especially relevant and should be included in the structure models. This is the case of...
Cluster-like structures are often present in atomic nuclei and significantly influence their structural and dynamical properties. More precisely, Morinaga [1] proposed a particular alpha cluster configuration known as the linear-chain cluster state (LCCS), in which the alpha particles are arranged in a linear sequence. In this configuration, the neutron excess appears to play a significant...
Isotopes close to the doubly-magic nuclei $^{132}$Sn are of strong interest from the point of view of nuclear structure. Spectroscopic studies are performed with the aim of obtaining a better understanding of the evolution of shell orbits in nuclei with large N/Z ratios, and providing critical tests of theoretical models. The information on the nuclear structure and decay properties of n-rich...
Proton and neutron removal reactions across the Be-Li chain close to the drip line have been investigated to establish the role of the Geometrical Mismatch Factor (GMF) and the Short-Range Correlations (SRC) effects [1] in lowering the cross sections, as observed previously in He-Li nuclei when compared to theoretical predictions [2] in what is widely known as the quenching of Spectroscopic...
The nuclear many-body problem is known to be computationally expensive to solve. Recently, with the advent of machine learning techniques in science, the method of Neural-Network Quantum States is being adopted by different groups to tackle nuclear systems, with the hope that it will be more efficient than the alternatives. Being a variational method, one of the inherent difficulties is to...
With the arrival of the HiCARI campaign [1] to the RIBF facility at RIKEN (Japan), a series of in-
beam g-ray spectroscopy experiments was performed in order to expand the previous spectroscopic
information on exotic, neutron-rich nuclei of intermediate mass. Previously, incompatible results
regarding the reduced transition probability for the decay of the first excited 2+ state, B(E2), in...
Nuclear effects in neutrino-nucleus scattering are one of the main sources of uncertainty in the analysis of neutrino oscillation experiments. Due to the extended neutrino energy distribution, very different reaction mechanisms contribute to the cross section at the same time. Measurements of muon momentum in CC0π events are very important for experiments like T2K, where most of the...
The use of thermal neutron radiation is widespread across numerous fields and its use is a core component of many different experiments, including the study of fission and fusion, archeology, astrophysics, medicine or research applications. Such experiments are mostly carried out in nuclear reactors, which are the most intense thermal neutron source. This makes measuring in research reactors...
Neutrinoless double-beta decay ($0\nu\beta\beta$) is a transition in nuclei where two neutrons simultaneously transform into two protons, accompanied by the emission of only two electrons [1]. This second-order process, if observed, would prove that neutrinos are Majorana particles (their own antiparticles), shed light on the existence of massive neutrinos, and help explain the predominance of...
