1,309 research outputs found
Transmission resonance spectroscopy in the third minimum of 232Pa
The fission probability of 232Pa was measured as a function of the excitation
energy in order to search for hyperdeformed (HD) transmission resonances using
the (d,pf) transfer reaction on a radioactive 231Pa target. The experiment was
performed at the Tandem accelerator of the Maier-Leibnitz Laboratory (MLL) at
Garching using the 231Pa(d,pf) reaction at a bombarding energy of E=12 MeV and
with an energy resolution of dE=5.5 keV. Two groups of transmission resonances
have been observed at excitation energies of E=5.7 and 5.9 MeV. The fine
structure of the resonance group at E=5.7 MeV could be interpreted as
overlapping rotational bands with a rotational parameter characteristic to a HD
nuclear shape. The fission barrier parameters of 232Pa have been determined by
fitting TALYS 1.2 nuclear reaction code calculations to the overall structure
of the fission probability. From the average level spacing of the J=4 states,
the excitation energy of the ground state of the 3rd minimum has been deduced
to be E(III)=5.05 MeV.Comment: 6 pages, 8 figure
Low-lying GT(+) strength in Co-64 studied via the Ni-64(d,He-2)Co-64 reaction
The Ni-64(d,He-2)Co-64 reaction was studied at the AGOR cyclotron of KVI, Groningen, with the Big-Bite Spectrometer and the EuroSuperNova detector using a 171-MeV deuteron beam. An energy resolution of about 110 keV was achieved. In addition to the J(pi) = 1(+) ground state, several other 1(+) states could be identified in Co-64 and the strengths of the corresponding Gamow-Teller transitions were determined. The obtained strength distribution was compared with theoretical predictions and former (n,p) experimental results and displayed a good agreement. Due to the good energy resolution, detailed spectroscopic information was obtained, which supplements the data base needed for network calculations for supernova scenarios
Polarization Correlations of 1S0 Proton Pairs as Tests of Bell and Wigner Inequalities
In an experiment designed to overcome the loophole of observer dependent
reality and satisfying the counterfactuality condition, we measured
polarization correlations of 1S0 proton pairs produced in 12C(d,2He) and
1H(d,He) reactions in one setting. The results of these measurements are used
to test the Bell and Wigner inequalties against the predictions of quantum
mechanics.Comment: 8 pages, 4 figure
Superdeformed rotational bands in Pu-240
The intermediate structure of the fission resonances has been observed in Pu-240. A resonance structure found around the excitation energy of 4.5 MeV was interpreted as a group of K-pi = 0(+) superdeformed rotational bands. The moments of inertia and level density distributions were also deduced for the individually observed band-heads
Chia-Yang Chen, clarinet
Max RegerKrzysztof PendereckiPaul PierneRoberto SierraGeorge Gershwi
Overtones of isoscalar giant resonances studied in direct particle decay measurements
The isoscalar giant dipole resonance (ISGDR), which is the lowest-energy overtone mode of the isoscalar giant resonances, has been studied in some medium-heavy and heavy nuclei in coincidence measurements. The observation of the direct nucleon decay channels significantly helped to enhance giant resonance strengths with respect to the underlying background and continuum, which gave an indication for the existence of a new mode with L = 2 character, assumingly the overtone of the ISGQR
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