120551728
Magnetic dipole and electric quadrupole rotational structures and chirality in Rh-105
The $^{105}\mathrm{Rh}$ nucleus has been studied with the $^{100}\mathrm{Mo}(^{11}\mathrm{B},\ensuremath{\alpha}2n\ensuremath{\gamma})$ reaction at $43\phantom{\rule{0.3em}{0ex}}\text{MeV}$ incident energy. A rich variety of structures was observed at high and low spins, using $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}t$ and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\mathit{particle}$ coincidences and directional correlation ratios. A $\ensuremath{\gamma}$-vibrational band was observed for the first time in this nucleus. A new structure based on the intruder $1∕{2}^{+}$[431] proton orbital was identified. Four magnetic dipole bands have also been observed at high spin, three of which have negative parity and have similar characteristics: they are very regular in energy spacing, presenting nearly constant alignments and large values of $B(M1)∕B(E2)$ ratios. Two of them are nearly degenerate in excitation energy and could be chiral partners. The $\ensuremath{\pi}{g}_{9∕2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11∕2}({g}_{7∕2},{d}_{5∕2})$ configuration is tentatively assigned for these bands, with the angular momenta of the proton and neutron intruders and the collective angular momentum aligning along the three perpendicular axes of the triaxial core, as predicted by tilted axis cranking calculations.
118964632
ONSET OF COLLECTIVITY IN NEUTRON-DEFICIENT PO-196,PO-198
We have studied via in-beam gamma-ray spectroscopy Po-196 and Po-198, which are the first neutron-deficient Po isotopes to exhibit a collective low-lying structure. The ratios of yrast state energi ...
103381576
High-spin state spectroscopy of Dy-143
29454387
Lifetimes of the decay from superdeformed to normal deformed in 135Nd.
Lifetimes of low-spin members of the superdeformed band in [sup 135]Nd have been determined by the Doppler-shift recoil-distance method. We find a quadrupole moment of 7.2[sub [minus]1.5][sup +1.2] b for the 677 keV (37/2- 33) / 2 transition in the band, confirming the large deformation previously measured by the Doppler-shift attenuation method. However, the quadrupole moment for the 620 keV transition deexciting the 3.324 MeV (25/2) state at the bottom of the band is much smaller. We conclude that the superdeformed potential-energy minimum disappears or the band drastically changes character at this point which causes the sudden depopulation.
115819581
Shears bands in Pb-193
Four bands of enhanced dipole transitions, with weak crossovers, have been observed in Pb-195. Three of these bands are connected to the spherical levels. in addition, the spherical level scheme ha ...
104250414
High-spin state spectroscopy in Tb-143
119244125
Fermion perturbations in string theory black holes
In this paper we study fermion perturbations in four-dimensional black holes of string theory, obtained either from a non-extreme configuration of three intersecting five-branes with a boost along the common string or from a non-extreme intersecting system of two two-branes and two five-branes. The Dirac equation for the massless neutrino field, after conformal re-scaling of the metric, is written as a wave equation suitable to study the time evolution of the perturbation. We perform a numerical integration of the evolution equation, and with the aid of Prony fitting of the time-domain profile, we calculate the complex frequencies that dominate the quasinormal ringing stage, and also determine these quantities by the semi-analytical sixth-order WKB method. We also find numerically the decay factor of fermion fields at very late times, and show that the falloff is identical to those showing for massless fields in other four-dimensional black hole spacetimes.
125114851
Vaccum polarization effects on quasinormal modes in electrically charged black hole spacetimes
119432093
Solutions for Klein-Gordon equation in Randall-Sundrum-Kerr scenario
We study the scalar perturbations of rotating black holes in framework of extra dimensions type Randall-Sundrum(RS).
119277724
VACUUM POLARIZATION EFFECTS ON QUASINORMAL MODES IN ELECTRICALLY CHARGED BLACK HOLE SPACE–TIMES
We investigate the influence of vacuum polarization of quantum massive fields on the scalar sector of quasinormal modes in spherically symmetric black holes. We consider the evolution of a massless scalar field on the space–time corresponding to a charged semiclassical black hole, consisting of the quantum-corrected geometry of a Reissner–Nordstrom black hole dressed by a quantum massive scalar field in the large mass limit. Using a sixth order WKB approach we find a shift in the quasinormal mode frequencies due to vacuum polarization.
118686912
Stability analysis and area spectrum of three-dimensional Lifshitz black holes
In this work, we probe the stability of a $z=3$ three-dimensional Lifshitz black hole by using scalar and spinorial perturbations. We found an analytical expression for the quasinormal frequencies of the scalar probe field, which perfectly agree with the behavior of the quasinormal modes obtained numerically. The results for the numerical analysis of the spinorial perturbations reinforce the conclusion of the scalar analysis, i.e., the model is stable under scalar and spinor perturbations. As an application we found the area spectrum of the Lifshitz black hole, which turns out to be equally spaced.