A5076233144- Nuclear physics research studies
- Astronomical and nuclear sciences
- Advanced Chemical Physics Studies
- Nuclear Physics and Applications
- Quantum Chromodynamics and Particle Interactions
- Gamma-ray bursts and supernovae
- Nuclear reactor physics and engineering
- Atomic and Molecular Physics
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Pulsars and Gravitational Waves Research
- Superconductivity in MgB2 and Alloys
- Cold Fusion and Nuclear Reactions
- Chemical Thermodynamics and Molecular Structure
- Astronomical Observations and Instrumentation
- Particle physics theoretical and experimental studies
- Superconducting Materials and Applications
- Astrophysical Phenomena and Observations
- High-pressure geophysics and materials
- Particle Accelerators and Free-Electron Lasers
- Quantum chaos and dynamical systems
- Field-Flow Fractionation Techniques
- Particle accelerators and beam dynamics
- Scientific Research and Discoveries
- Quantum, superfluid, helium dynamics
University of Surrey
2021-2024
Universidad Autónoma de Madrid
2013-2024
Michigan State University
2018-2022
European Centre for Theoretical Studies in Nuclear Physics and Related Areas
2022
National Superconducting Cyclotron Laboratory
2019-2020
Technical University of Darmstadt
2014-2018
Superheavy atoms and their nuclei are at the forefront of experimental theoretical nuclear atomic physics, chemistry. Because large numbers, traditional concepts have to be revised in superheavy systems. In this Colloquium latest developments field described route for future scientific explorations area research is indicated.
There has been much recent interest in nuclear fission, due part to a new appreciation of its relevance astrophysics, stability superheavy elements, and fundamental theory neutrino interactions. At the same time, there have important developments on conceptual computational level for theory. The promising theoretical avenues were subject workshop held at University York October 2019; this report summarises findings recommendations.
We computed a new set of static fission properties suited for $r$-process calculations. The potential energy surfaces and collective inertias 3640 nuclei in the superheavy region are obtained from self-consistent mean-field calculations using Barcelona-Catania-Paris-Madrid density functional. path is as function quadrupole moment by minimizing exploring octupole hexadecapole deformations. spontaneous lifetimes evaluated employing different schemes vibrational corrections. This allows us to...
The chart of the nuclides is limited by particle drip lines beyond which nuclear stability to proton or neutron emission lost. Predicting range particle-bound isotopes poses an appreciable challenge for theory as it involves extreme extrapolations masses regions where experimental information available. Still, quantified are crucial a variety applications, including modeling stellar nucleosynthesis. We use microscopic mass models and Bayesian methodology provide predictions separation...
The properties of dynamic (least action) fission paths are analyzed and compared to the ones more traditional static energy) paths. Both Barcelona-Catania-Paris-Madrid Gogny D1M energy density functionals used in calculation Hartree-Fock-Bogoliubov (HFB) constrained configurations providing potential collective inertias. action is computed as Wentzel-Kramers-Brillouin method. A full variational search least-action path over complete space HFB wave functions cumbersome probably unnecessary if...
According to theory, cluster radioactivity becomes an important decay mode in superheavy nuclei. In this work, we predict that the strongly-asymmetric fission, or emission, is fact dominant fission channel for $^{294}_{118}$Og$_{176}$, which currently heaviest synthetic isotope known. Our theoretical approach incorporates features of dynamics, including quantum tunneling and stochastic dynamics up scission. We show that, despite appreciable differences static properties such as barriers...
Background: Large-scale computations of fission properties are an important ingredient for nuclear reaction network calculations simulating rapid neutron-capture process (the $r$ process) nucleosynthesis. Due to the large number fissioning nuclei potentially contributing process, a microscopic description based on density functional theory (DFT) is computationally challenging.Purpose: We explore use neural networks (NNs) construct DFT emulators capable predicting potential energy surfaces...
Fission dynamics properties of the Barcelona-Catania-Paris-Madrid energy density functional are explored with mean-field techniques. Potential surfaces as well collective inertias relevant in fission process computed for several nuclei where experimental data exist. Inner and outer barrier heights isomer excitation energies reproduced quite all cases. The spontaneous half-lives ${t}_{\mathrm{sf}}$ also using standard semiclassical approach results compared data. trend mass number is...
The limits of the nuclear landscape are determined by binding energies. Beyond proton drip lines, where separation energy becomes negative, there is not enough to prevent protons from escaping nucleus. Predicting properties unstable states in vast territory emitters poses an appreciable challenge for theory as it often involves far extrapolations. In addition, significant discrepancies between models proton-rich call quantified predictions. With help Bayesian methodology, we mix a family...
We study the impact of fission on production and destruction translead nuclei during r-process nucleosynthesis occurring in neutron-star mergers. Abundance patterns rates nuclear energy are obtained for different ejecta conditions using three sets stellar reaction rates, one which is based microscopic consistent calculations masses, barriers, collective inertias. show that accumulation fissioning material r process can strongly affect free neutron abundance after freeze-out. This leads to a...
Background: A quantitative microscopic understanding of the fission-fragment yield distributions represents a major challenge for nuclear theory as it involves intricate competition between large-amplitude collective motion and single-particle nucleonic motion. Purpose: recently proposed approach to global modeling fission fragment is extended account odd-even staggering in charge yields neutron evaporation. Method: Fission trajectories are obtained within density functional framework,...
Background: More than half of all the elements heavier iron are made by rapid neutron capture process (or $r$ process). For very-neutron-rich astrophysical conditions, such at those found in tidal ejecta stars, nuclear fission determines $r$-process endpoint, and fission-fragment yields shape final abundances $110\ensuremath{\le}A\ensuremath{\le}170$ nuclei. The knowledge hundreds nuclei inhabiting regions landscape is thus crucial for modeling heavy-element nucleosynthesis.Purpose: In this...
The non-perturbative method to compute Adiabatic Time Dependent Hartree Fock Bogoliubov (ATDHFB) collective inertias is extended the Generator Coordinate Method (GCM) in Gaussian overlap approximation (GOA) including case of density dependent forces. two schemes are computed along fission path 234U and compared with perturbative results. We find that predict very similar a much richer structure than one predicted by calculations. Moreover, show an extraordinary similitude exact GCM...
We study the role of dynamic pairing correlations in fission dynamics by considering intrinsic Hartree-Fock-Bogoliubov wave functions that are obtained minimizing particle number projected energy. For restricted variational space, set self-consistent with different values proton and neutron fluctuations considered. The energy is used to define potential surface for whereas collective inertias computed within traditional formulas states. results show effect variation after projection small...
Abstract The next years will see the completion of radioactive ion beam facility SPES (Selective Production Exotic Species) and upgrade accelerators complex at Istituto Nazionale di Fisica Nucleare – Legnaro National Laboratories (LNL) opening up new possibilities in fields nuclear structure, dynamics, astrophysics, applications. physics community has organised a workshop to discuss opportunities that be possible near future by employing state-of-the-art detection systems. A detailed...
Background: When multiple fission modes coexist in a given nucleus, distinct fragment yield distributions appear. Multimodal has been observed number of fissioning nuclei spanning the nuclear chart, and this phenomenon is expected to affect abundances synthesized during rapid neutron-capture process ($r$-process).Purpose: In study, we generalize previously proposed hybrid model for fission-fragment predict competing estimate resulting distributions. Our framework allows comprehensive...
An extension of the Barcelona Catania Paris Madrid (BCPM) energy density functional is proposed to deal with odd-mass systems as well multiquasiparticle excitations. The based on assumption that equal filling approximation (EFA) a valid alternative traditional full blocking procedure Hartree-Fock-Bogoliubov method. supported by excellent agreement between and EFA calculations obtained different parametrizations Gogny interaction. augmented BCPM used compute low excitation spectra selected...
In July 2018 an FRIB Theory Alliance program was held on the implications of GW170817 and its associated kilonova for r-process nucleosynthesis. Topics discussion included astrophysical nuclear physics uncertainties in interpretation kilonova, what we can learn about site or sites r process from this event, advances experiment theory most crucial to pursue light new data. Here compile a selection scientific contributions workshop, broadly representative progress studies since event.
Pairing plays a crucial role in the microscopic description of nuclear fission. Microscopic methods provide access to three quantities related pairing, namely, pairing gap ($\Delta$), particle number fluctuations ($ \Delta \hat{N}^2 $), and quenching factor (QF). The aim this work is analyse impact each these on static fission process.
Decomposing theoretical nuclear mass predictions into a liquid-drop parametrization and local shell effects shows that r-process abundances are virtually insensitive to large variations of the masses which originate from bulk properties model, such as symmetry energy. Therefore, experimental studies devoted applications, nucleosynthesis in ejecta neutron star mergers, should focus on physical origin changes trends without necessarily providing highly accurate determinations individual nuclei.
Dependable predictions of the X-ray burst ashes and light curves require a stringent constraint on composition accreted material as an input parameter. Lower metallicity models are generally based metal deficient donor all metals summed up in CNO abundances or solar distribution is assumed. In this work, we study alteration due to spallation atmosphere accreting neutron stars considering cascading destruction process. We find that inclusion process brings replenishment elements overall...
An extension of the Barcelona Catania Paris Madrid (BCPM) energy density functional is proposed to deal with odd mass systems as well quasiparticle excitations. The based on assumption that equal filling approximation (EFA) its time-even densities a very good substitute traditional full blocking Hartree-Fock-Bogoliubov method. supported by excellent agreement results those EFA for Gogny forces and Skyrme functionals. augmented BCPM used compute low excitation spectra selected nuclei in...
Abstract We study the cluster emission properties of $$^{224}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow /> <mml:mn>224</mml:mn> </mml:msup> </mml:math> Ra and $$^{238}$$ <mml:mn>238</mml:mn> Pu employing Barcelona-Catania-Paris-Madrid (BCPM) energy density functional (EDF). Starting from two-dimensional potential surfaces, coexisting fission paths are identified. A valley located at large octupole deformations, corresponding to a highly-asymmetric mass...