5,321 research outputs found
No-Core Shell Model for Nuclear Systems with Strangeness
We report on a novel ab initio approach for nuclear few- and many-body
systems with strangeness. Recently, we developed a relevant no-core shell model
technique which we successfully applied in first calculations of lightest
hypernuclei. The use of a translationally invariant finite harmonic
oscillator basis allows us to employ large model spaces, compared to
traditional shell model calculations, and use realistic nucleon-nucleon and
nucleon-hyperon interactions (such as those derived from EFT). We discuss
formal aspects of the methodology, show first demonstrative results for
H, H and He, and give outlook.Comment: 4 pages, 3 figures; Proceedings of the 22nd European Conference on
Few Body Problems in Physics, 9 - 13 September, 2013, Cracow, Polan
Ab Initio Treatment of Collective Correlations and the Neutrinoless Double Beta Decay of Ca
Working with Hamiltonians from chiral effective field theory, we develop a
novel framework for describing arbitrary deformed medium-mass nuclei by
combining the in-medium similarity renormalization group with the generator
coordinate method. The approach leverages the ability of the first method to
capture dynamic correlations and the second to include collective correlations
without violating symmetries. We use our scheme to compute the matrix element
that governs the neutrinoless double beta decay of Ca to Ti, and
find it to have the value , near or below the predictions of most
phenomenological methods. The result opens the door to ab initio calculations
of the matrix elements for the decay of heavier nuclei such as Ge,
Te, and Xe.Comment: 6 pages, 4 figures and 1 table. supplementary material included.
version to be publishe
COMBINING TASTE PANELS WITH FOCUS GROUPS TO ELICIT CONSUMER PREFERENCES TOWARD A NEW SHRIMP PRODUCT
Consumer/Household Economics,
Logarithmic behavior of degradation dynamics in metal--oxide semiconductor devices
In this paper the authors describe a theoretical simple statistical modelling
of relaxation process in metal-oxide semiconductor devices that governs its
degradation. Basically, starting from an initial state where a given number of
traps are occupied, the dynamics of the relaxation process is measured
calculating the density of occupied traps and its fluctuations (second moment)
as function of time. Our theoretical results show a universal logarithmic law
for the density of occupied traps , i.e., the degradation is logarithmic and its amplitude depends on the
temperature and Fermi Level of device. Our approach reduces the work to the
averages determined by simple binomial sums that are corroborated by our Monte
Carlo simulations and by experimental results from literature, which bear in
mind enlightening elucidations about the physics of degradation of
semiconductor devices of our modern life
The influence of oscillations on energy estimates for damped wave models with time-dependent propagation speed and dissipation
The aim of this paper is to derive higher order energy estimates for
solutions to the Cauchy problem for damped wave models with time-dependent
propagation speed and dissipation. The model of interest is \begin{equation*}
u_{tt}-\lambda^2(t)\omega^2(t)\Delta u +\rho(t)\omega(t)u_t=0, \quad
u(0,x)=u_0(x), \,\, u_t(0,x)=u_1(x). \end{equation*} The coefficients
and are shape functions and
is an oscillating function. If and
is an "effective" dissipation term, then energy
estimates are proved in [2]. In contrast, the main goal of the present paper is
to generalize the previous results to coefficients including an oscillating
function in the time-dependent coefficients. We will explain how the interplay
between the shape functions and oscillating behavior of the coefficient will
influence energy estimates.Comment: 37 pages, 2 figure
New supersymmetric quartet of nuclei in the A=190 mass region
We present evidence for a new supersymmetric quartet in the A=190 region of
the nuclear mass table. New experimental information on transfer and neutron
capture reactions to the odd-odd nucleaus 194 Ir strongly suggests the
existence of a new supersymmetric quartet, consisting of the 192,193 Os and
193,194 Ir nuclei. We make explicit predictions for the odd-neutron nucleus 193
Os, and suggest that its spectroscopic properties be measured in dedicated
experiments.Comment: 5 pages, 4 figures, updated figures and revised text, Physical Review
C, Rapid Communication, in pres
Attosecond control of electron dynamics in carbon monoxide
Laser pulses with stable electric field waveforms establish the opportunity
to achieve coherent control on attosecond timescales. We present experimental
and theoretical results on the steering of electronic motion in a
multi-electron system. A very high degree of light-waveform control over the
directional emission of C+ and O+ fragments from the dissociative ionization of
CO was observed. Ab initio based model calculations reveal contributions to the
control related to the ionization and laser-induced population transfer between
excited electronic states of CO+ during dissociation
New supersymmetric quartet of nuclei in the A=190 mass region
We present evidence for a new supersymmetric quartet in the A=190 region of
the nuclear mass table. New experimental information on transfer and neutron
capture reactions to the odd-odd nucleaus 194 Ir strongly suggests the
existence of a new supersymmetric quartet, consisting of the 192,193 Os and
193,194 Ir nuclei. We make explicit predictions for the odd-neutron nucleus 193
Os, and suggest that its spectroscopic properties be measured in dedicated
experiments.Comment: 5 pages, 4 figures, updated figures and revised text, Physical Review
C, Rapid Communication, in pres
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