720 research outputs found
Alternative Interpretation of Sharply Rising E0 Strengths in Transitional Regions
It is shown that strong 0+2 -> 0+1 E0 transitions provide a clear signature
of phase transitional behavior in finite nuclei. Calculations using the IBA
show that these transition strengths exhibit a dramatic and robust increase in
spherical-deformed shape transition regions, that this rise matches well the
existing data, that the predictions of these E0 transitions remain large in
deformed nuclei, and that these properties are intrinsic to the way that
collectivity and deformation develop through the phase transitional region in
the model, arising from the specific d-boson coherence in the wave functions,
and that they do not necessarily require the explicit mixing of normal and
intruder configurations from different IBA spaces.Comment: 6 pages, 3 figure
Anesthetic Management For Enhanced Recovery After Cardiac Surgery (ERACS)
Since the advent of the Enhanced Recovery After Surgery (ERAS) initiative, enhanced recovery protocols exist for many surgical specialties. Many studies have shown the benefits of the ERAS-based approach in improving outcomes, minimizing complications, and reducing costs. Similar protocols were developed to potentially reap these benefits for patients undergoing cardiac surgery and are now known as the Enhanced Recovery After Cardiac Surgery (ERACS). This activity reviews the ERACS guidelines released by the ERAS cardiac society to help the management by an interprofessional team
Exactly separable version of the Bohr Hamiltonian with the Davidson potential
An exactly separable version of the Bohr Hamiltonian is developed using a
potential of the form u(beta)+u(gamma)/beta^2, with the Davidson potential
u(beta)= beta^2 + beta_0^4/beta^2 (where beta_0 is the position of the minimum)
and a stiff harmonic oscillator for u(gamma) centered at gamma=0. In the
resulting solution, called exactly separable Davidson (ES-D), the ground state
band, gamma band and 0_2^+ band are all treated on an equal footing. The
bandheads, energy spacings within bands, and a number of interband and
intraband B(E2) transition rates are well reproduced for almost all
well-deformed rare earth and actinide nuclei using two parameters (beta_0,
gamma stiffness). Insights regarding the recently found correlation between
gamma stiffness and the gamma-bandhead energy, as well as the long standing
problem of producing a level scheme with Interacting Boson Approximation SU(3)
degeneracies from the Bohr Hamiltonian, are also obtained.Comment: 35 pages, 11 postscript figures, LaTe
The role of the g9/2 orbital in the development of collectivity in the A = 60 region: The case of 61Co
An extensive study of the level structure of 61Co has been performed
following the complex 26Mg(48Ca, 2a4npg)61Co reaction at beam energies of 275,
290 and 320 MeV using Gammasphere and the Fragment Mass Analyzer (FMA). The
low-spin structure is discussed within the framework of shell-model
calculations using the GXPF1A effective interaction. Two quasi-rotational bands
consisting of stretched-E2 transitions have been established up to spins I =
41/2 and (43/2), and excitation energies of 17 and 20 MeV, respectively. These
are interpreted as signature partners built on a neutron {\nu}(g9/2)2
configuration coupled to a proton {\pi}p3/2 state, based on Cranked Shell Model
(CSM) calculations and comparisons with observations in neighboring nuclei. In
addition, four I = 1 bands were populated to high spin, with the yrast dipole
band interpreted as a possible candidate for the shears mechanism, a process
seldom observed thus far in this mass region
Lifetime determination of excited states in Cd-106
Two separate experiments using the Differential Decay Curve Method have been performed to extract mean lifetimes of excited states in 106 Cd. The inedium-spin states of interest were populated by the Mo-98(C-12, 4n) Cd-106 reaction performed at the Wright Nuclear Structure Lab., Yale University. From this experiment, two isomeric state mean lifetimes have been deduced. The low-lying states were populated by the Mo-96(C-13, 3n)Cd-106 reaction performed at the Institut fur Kernphysik, Universitat zu Koln. The mean lifetime of the I-pi = 2(1)(+) state was deduced, tentatively, as 16.4(9) ps. This value differs from the previously accepted literature value from Coulomb excitation of 10.43(9) ps
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