0000000000164260
AUTHOR
M. Kortelainen
Low energy collective modes of deformed superfluid nuclei within the finite amplitude method
Background: The major challenge for nuclear theory is to describe and predict global properties and collective modes of atomic nuclei. Of particular interest is the response of the nucleus to a time-dependent external field that impacts the low-energy multipole and beta-decay strength. Purpose: We propose a method to compute low-lying collective modes in deformed nuclei within the finite amplitude method (FAM) based on the quasiparticle random-phase approximation (QRPA). By using the analytic property of the response function, we find the QRPA amplitudes by computing the residua of the FAM amplitudes by means of a contour integration around the QRPA poles in a complex frequency plane. Metho…
Nuclear energy density optimization: Shell structure
Nuclear density functional theory is the only microscopical theory that can be applied throughout the entire nuclear landscape. Its key ingredient is the energy density functional. In this work, we propose a new parameterization UNEDF2 of the Skyrme energy density functional. The functional optimization is carried out using the POUNDerS optimization algorithm within the framework of the Skyrme Hartree-Fock-Bogoliubov theory. Compared to the previous parameterization UNEDF1, restrictions on the tensor term of the energy density have been lifted, yielding a very general form of the energy density functional up to second order in derivatives of the one-body density matrix. In order to impose c…
The limits of the nuclear landscape
In 2011, 100 new nuclides were discovered. They joined the approximately 3,000 stable and radioactive nuclides that either occur naturally on Earth or are synthesized in the laboratory. Every atomic nucleus, characterized by a specific number of protons and neutrons, occupies a spot on the chart of nuclides, which is bounded by 'drip lines' indicating the values of neutron and proton number at which nuclear binding ends. The placement of the neutron drip line for the heavier elements is based on theoretical predictions using extreme extrapolations, and so is uncertain. However, it is not known how uncertain it is or how many protons and neutrons can be bound in a nucleus. Here we estimate t…
Short-range correlations and neutrinoless double beta decay
In this work we report on the effects of short-range correlations upon the matrix elements of neutrinoless double beta decay. We focus on the calculation of the matrix elements of the neutrino-mass mode of neutrinoless double beta decays of 48Ca and 76Ge. The nuclear-structure components of the calculation, that is the participant nuclear wave functions, have been calculated in the shell-model scheme for 48Ca and in the proton-neutron quasiparticle random-phase approximation (pnQRPA) scheme for 76Ge. We compare the traditional approach of using the Jastrow correlation function with the more complete scheme of the unitary correlation operator method (UCOM). Our results indicate that the Jast…
Accurate Q value for the 74Se double-electron-capture decay
Abstract The Q value of the neutrinoless double-electron-capture ( 0 ν ECEC ) decay of 74Se was measured by using the JYFLTRAP Penning trap. The determined value is 1209.169(49) keV, which practically excludes the possibility of a complete energy degeneracy with the second 2 + state (1204.205(7) keV) of 74Ge in a resonant 0 ν ECEC decay. We have also computed the associated nuclear matrix element by using a microscopic nuclear model with realistic two-nucleon interactions. The computed matrix element is found to be quite small. The failure of the resonant condition, combined with the small nuclear matrix element and needed p-wave capture, suppresses the decay rate strongly and thus excludes…
Computational nuclear quantum many-body problem: The UNEDF project
The UNEDF project was a large-scale collaborative effort that applied high-performance computing to the nuclear quantum many-body problem. The primary focus of the project was on constructing, validating, and applying an optimized nuclear energy density functional, which entailed a wide range of pioneering developments in microscopic nuclear structure and reactions, algorithms, high-performance computing, and uncertainty quantification. UNEDF demonstrated that close associations among nuclear physicists, mathematicians, and computer scientists can lead to novel physics outcomes built on algorithmic innovations and computational developments. This review showcases a wide range of UNEDF scien…
Correlating Schiff Moments in the Light Actinides with Octupole Moments
We show that the measured intrinsic octupole moments of $^{220}$Rn, $^{224}$Ra, and $^{226}$Ra constrain the intrinsic Schiff moments of $^{225}$Ra$^{221}$Rn, $^{223}$Rn, $^{223}$Fr, $^{225}$Ra, and $^{229}$Pa. The result is a dramatically reduced uncertainty in intrinsic Schiff moments. Direct measurements of octupole moments in odd nuclei will reduce the uncertainty even more. The only significant source of nuclear-physics error in the laboratory Schiff moments will then be the intrinsic matrix elements of the time-reversal non-invariant interaction produced by CP-violating fundamental physics. Those matrix elements are also correlated with octupole moments, but with a larger systematic u…
Nuclear DFT electromagnetic moments in heavy deformed open-shell odd nuclei
Within the nuclear DFT approach, we determined the magnetic dipole and electric quadrupole moments for paired nuclear states corresponding to the proton (neutron) quasiparticles blocked in the p11/2- (n13/2+) intruder configurations. We performed calculations for all deformed open-shell odd nuclei with 63<=Z<=82 and 82<=N<=126. Time-reversal symmetry was broken in the intrinsic reference frame and self-consistent shape and spin core polarizations were established. We determined spectroscopic moments of angular-momentum-projected wave functions and compared them with available experimental data. We obtained good agreement with data without using effective g-factors or effective c…
Probing double beta decay by nuclear muon capture
A reliable theoretical calculations on two-neutrino and neutrinoless double-beta-decay rates requires a solid description about the nuclear structure of the intermediate nuclear states. It has been suggested that the ordinary muon capture could be used to probe the structure of the intermediate states in double beta decays.
Impact of Nuclear Deformation and Pairing on the Charge Radii of Palladium Isotopes.
International audience; The impact of nuclear deformation can been seen in the systematics of nuclear charge radii, with radii generally expanding with increasing deformation. In this Letter, we present a detailed analysis of the precise relationship between nuclear quadrupole deformation and the nuclear size. Our approach combines the first measurements of the changes in the mean-square charge radii of well-deformed palladium isotopes between A=98 and A=118 with nuclear density functional calculations using Fayans functionals, specifically Fy(std) and Fy(Δr,HFB), and the UNEDF2 functional. The changes in mean-square charge radii are extracted from collinear laser spectroscopy measurements …
Theoretical direct WIMP detection rates for transitions to nuclear excited states
The recent WMAP and Planck data have confirmed that exotic dark matter together with the vacuum energy (cosmological constant) dominate in the flat Universe. Many extensions of the standard model provide dark matter candidates, in particular Weakly Interacting Massive Particles (WIMPs). Thus the direct dark matter detection is central to particle physics and cosmology. Most of the research on this issue has hitherto focused on the detection of the recoiling nucleus. In this paper we study transitions to the excited states, possible in some nuclei, which have sufficiently low lying excited states. Examples considered previously were the first excited states of $^{127}$I and $^{129}$Xe. We ex…
Neutron-skin uncertainties of Skyrme energy density functionals
Background: Neutron-skin thickness is an excellent indicator of isovector properties of atomic nuclei. As such, it correlates strongly with observables in finite nuclei that depend on neutron-to-proton imbalance and the nuclear symmetry energy that characterizes the equation of state of neutron-rich matter. A rich worldwide experimental program involving studies with rare isotopes, parity violating electron scattering, and astronomical observations is devoted to pinning down the isovector sector of nuclear models. Purpose: We assess the theoretical systematic and statistical uncertainties of neutron-skin thickness and relate them to the equation of state of nuclear matter, and in particular…
Analysis of the 2νββ decay and muon capture reactions for the mass A = 46 and A = 48 nuclei using the nuclear shell model
We discuss the two-neutrino double-beta decays of 46Ca and 48Ca by using the nuclear shell model with well-tested two-body interactions. We also discuss the ordinary muon-capture (OMC) reaction on the final nuclei, 46Ti and 48Ti, of these decays. The OMC leads to the virtual states of the intermediate nuclei, 46Sc and 48Sc, in these double-beta decays.
Axially deformed solution of the Skyrme-Hartree-Fock-Bogolyubov equations using the transformed harmonic oscillator basis (II) HFBTHO v2.00d: a new version of the program
We describe the new version 2.00d of the code HFBTHO that solves the nuclear Skyrme Hartree-Fock (HF) or Skyrme Hartree-Fock-Bogolyubov (HFB) problem by using the cylindrical transformed deformed harmonic-oscillator basis. In the new version, we have implemented the following features: (i) the modified Broyden method for non-linear problems, (ii) optional breaking of reflection symmetry, (iii) calculation of axial multipole moments, (iv) finite temperature formalism for the HFB method, (v) linear constraint method based on the approximation of the Random Phase Approximation (RPA) matrix for multi-constraint calculations, (vi) blocking of quasi-particles in the Equal Filling Approximation (E…
CCDC 879930: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879931: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879941: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879940: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879939: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879937: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879929: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879935: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879936: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879942: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879933: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879938: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879934: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t
CCDC 879932: Experimental Crystal Structure Determination
Related Article: A.Peuronen, A.Valkonen, M.Kortelainen, K.Rissanen, M.Lahtinen|2012|Cryst.Growth Des.|12|4157|doi:10.1021/cg300669t