Levels in <Superscript>127</Superscript>La fed by the <Superscript>127</Superscript>Ce beta-decay

The low-lying levels in ¹²⁷La have been studied through the -decay of ¹²⁷Ce ( T_1/2 = 29s) produced by bombarding a ^natMo target with a 185-MeV ³⁵Cl beam. Reaction products were on-line mass-separated, and -ray singles and - coincidence measurements were performed. Conversion electrons were also measured and multipolarities of transitions have been derived. The half-life of the 210.9-keV level was determined to be (1.9±0.3)ns by the - delayed coincidence technique. The level scheme obtained has been compared with calculations based on the Nilsson model.     

Collective structures of the <Superscript>131</Superscript>Cs nucleus

The collective structures of ¹³¹Cs have been investigated by in-beam -ray spectroscopic techniques following the ¹²⁴Sn (^11B , 4n) reaction at a beam energy E_lab = 57MeV. The previously established rotational bands, built on g_7/2, d_5/2 and the unique-parity h_11/2 orbitals, have been extended and evolve into new bands involving rotationally aligned (h_11/2)² and (h_11/2)² quasiparticles. In addition, a new multiquasiparticle band based on the g_7/2 g_7/2 h_11/2 configuration has also been observed. Theoretical interpretations for the assigned configurations are discussed in the framework of Total Routhian Surface (TRS) and Tilted Axis Cranking (TAC) model calculations. TAC model calculations predict a decrease in the B(M1) values with increasing rotational frequency for the g_7/2/d_5/2 (h_11/2)² and h_11/2 (h_11/2)² bands, thus indicating a magnetic rotation character for these bands.     

Coexisting oblate and strongly triaxial structures in <Superscript>191</Superscript>Pt

Excited states in ¹⁹¹Pt have been populated using the reaction ¹⁸⁶W + ¹¹B at 85MeV beam energy. Gamma-ray coincidences were measured using the EUROGAM-II spectrometer array. The level scheme has been extended considerably. Evidence for favoured structures of highly triaxial shape with -90^° coexisting with oblate structures has been obtained by comparison with total Routhian surface and cranked shell model calculations. The presence of proton excitations in both positive- and negative-parity states has been confirmed.     

Neutron and light-charged-particle productions in proton-induced reactions on 208Pb at 62.9 MeV

Neutrons and light charged particles produced in 62.9MeV proton-induced reactions on ²⁰⁸Pb were measured during a single experiment performed at the CYCLONE facility in Louvain-la-Neuve (Belgium). Two independent experimental set-ups were used to extract double differential cross-sections for neutrons, protons, deuterons, tritons, ³He and alpha-particles. Charged particles were detected using a set of Si- Si- CsI telescopes from 25^° to 155^°, by step of 10 degrees. Neutrons were measured using shielded DeMoN counters, liquid NE213 scintillators, at 24^°, 35^°, 55^°, 80^° and 120^°. These data allowed the determination of angle differential, energy differential and total production cross-sections. A comparison with theoretical calculations (MCNPX, FLUKA and TALYS) has been performed. It shows that the neutron and proton production rates are well predicted by MCNPX, using the INCL4 option. All the other codes underestimate the neutron production whereas they overestimate the proton one. For composite particles, which represent 17% of the charged particle total reaction cross-section, neither the shape nor the amplitude of the cross-sections are correctly predicted by the models.     

Spectroscopy of superheavy hydrogen isotopes <Superscript>4</Superscript>H and <Superscript>5</Superscript>H

The superheavy hydrogen isotopes ⁴H and ⁵H have been investigated in the stopped pion absorption on ⁹Be. Three states of ⁴H were proposed in the reaction channel ⁹Be( ^{{ - }}, dt)X. Four states of ⁵H were proposed in the reaction channels ⁹Be(^{{ - }}, pt)X and ⁹Be(^{{ - }}, dt)X. The excited states of ⁵H can decay into free nucleons.     

High-spin states and band structures in the doubly odd <Superscript>136</Superscript>La nucleus

High-spin states of ¹³⁶La have been investigated with the reaction ¹³⁰Te( ¹¹B, 5n) at a beam energy of 60 MeV. The level scheme with three collective bands has been updated with spin up to 20 . The observed h_11/2 h_11/2 band shows -instability with increasing spin according to the TRS calculations. The band crossing and the signature splitting and inversion have been discussed. Other two collective bands based on 12^-and 16⁺ levels were proposed as oblate deformation with -60^°. They most probably originate from four- and six-quasiparticle configurations, that is, h_11/2 g_7/2h_11/2² and g_7/2 g_7/2²d_5/2h_11/2² respectively.     

High-spin isomer in 93Mo

The high-spin states of ⁹³Mo have been studied by a ⁸²Se( ¹⁶O, 5n) ⁹³Mo reaction at a beam energy of 100 MeV using techniques of in-beam -ray spectroscopy. Measurements of -t, --t coincidences, -ray angular distributions and -ray linear polarizations were performed. The high-spin isomer was found as a (39/2^-) state at about 9.7 MeV. The near-yrast states in ⁹³Mo were interpreted using the weak-coupling picture of a d_5/2 neutron to a neutron magic core nucleus ⁹²Mo.     

Prolate structures in 189Po and 185Pb

The 3/2^- isomer in ¹⁸⁵Pb and states above it have been populated in the -decay of ¹⁸⁹Po. The observed -decay strengths to and the electromagnetic decay properties of the excited states in ¹⁸⁵Pb have been combined with Potential Energy Surface and Particle-Plus-Rotor calculations to propose configuration assignments. It is suggested that the -decaying isomer of ¹⁸⁹Po is of prolate origin and that the prolate configuration becomes very low in energy in ¹⁸⁵Pb.     

Beta-decay studies of neutron-rich Sc- Cr nuclei

The neutron-rich nuclei ₂₁^{57, 58}Sc, ₂₂^58-60Ti, ₂₃^60-63V, ₂₄^62-66Cr have been produced at Ganil via interactions of a 61.8A MeV ⁷⁶Ge beam with a ⁵⁸Ni target. Beta-decay studies have been performed using combined - and -ray spectroscopy. Half-lives have been determined and -decay schemes are proposed for ⁵⁸Ti, ⁶¹V and ⁶²Cr. From these studies, new hints for the existence of -decaying isomers in ⁶⁰V and in ⁶²Mn are provided. These results are compared to shell model calculations. The role of the f_7/2- f_5/2 proton-neutron interaction is examined through its influence on the lifetime values.     

Gravitational Waves in Matter

The theory of gravitational waves in matter is given. This covers the questions of constitutive relation, number of independent polarizations, index of refraction, reflection and refraction at an interface, etc. The theory parallels the familiar optics of electromagnetic waves in material media, but there are some striking differences. The use of the Campbell-Morgan formalism in which the gauge-invariant tidal force dyads E and B rather than the gauge-dependent metric perturbations are the unknowns is essential. The main justification of the theory at the moment is as a theoretical exercise worth doing. The assumption: size L of the medium gravitational wave length (infinite medium) rules out application to the already well-understood detection problem, but there may be an application to gravitational wave propagation through molecular gas clouds of galactic or inter-galactic size.     

Gamma-ray spectroscopy in 110Sn and 111Sn

Excited states in ¹¹⁰Sn and ¹¹¹Sn nuclei have been investigated using in-beam -ray spectroscopic methods. An ¹⁶O beam with an energy of 60-80MeV was used to bombard a ⁹⁸Mo target. On the basis of the relative excitation functions, -ray angular distributions, - and -time distributions, -ray multiplicity and total energy data, the level schemes of ¹¹⁰Sn and ¹¹¹Sn have been studied and extended up to E_exc 11.5MeV, I = 24, and E_exc 11.1MeV and I = (51/2), respectively. An extension of the intruder, g.s. and negative-parity bands, as well as 5 new band-like structures are proposed in ¹¹⁰Sn. The nature of newly introduced collective band 8 as well as 10⁺ states fed in the decay of the collective band is discussed. In the ¹¹¹Sn nucleus an intruder band based on the 23/2^- state has been reinvestigated and the extension of the g.s. band and second negative-parity band is given. Evidence for neutron-core coupling in ¹¹¹Sn is found. The structure and systematics of excited states in light Sn isotopes is discussed.     

Decay studies of <Superscript>210-214</Superscript>Fr using α- γ-coincidences

The -decay fine structure of ^210-214Fr has been studied by --coincidence measurements. The nuclei were produced using the ¹²C on ²⁰⁹Bi reaction. Evaporation residues recoiling out of the target were separated in-flight by the velocity filter SHIP and stopped in a position-sensitive 16-strip PIPS-detector in order to study their subsequent decays. In the present work new and improved results for ^210-214Fr, produced by -decay of the primary reaction products ^214-218Ac, were extracted. The results are discussed and compared to previously published data.     

Comment on the calculation of thermal averages by long-time Monte Carlo simulations

It is shown that the effect of turnovers of the whole spin lattice for temperatures below the ordering temperature during a long-time computer simulation is not always satisfactorily reduced by considering the absolute value of the order parameter. A simple method to overcome this problem is suggested.     

Pionic degrees of freedom in atomic nuclei and quasielastic knockout of pions by high-energy electrons

The microscopic mechanism of the identical bands in odd-odd nucleus ¹⁹⁴Tl and its neighbor odd-A nuclei ^193,195Tl is investigated using the particle-number-conserving (PNC) method for treating the cranked shell model with monopole and quadrupole pairing interactions. It is found that the blocking effect of the high-j intruder orbital plays an important role in the variation of moments of inertia (J⁽¹⁾ and J⁽²⁾) with rotational frequency for the superdeformed bands and identical bands. The variation of the occupation probability of each cranked orbital and the contributions to moment of inertia from each cranked orbital are presented.     

Variations on a Constant Theme

We describe how theories incorporating time-varying coupling constants can drive the Universe to a late-time near-flat attractor in which the cosmological constant is very small. We also discuss some consequences of allowing time-varying constants to vary in space as well.     

Precision measurement of the half-life and the decay branches of 62Ga

In an experiment performed at the Accelerator Laboratory of the University of Jyväskylä, the -decay half-life of ⁶²Ga has been studied with high precision using the IGISOL technique. A half-life of T_1/2 = 116.09(17) ms was measured. Using - coincidences, the intensity of the 954 keV transition and an upper limit of the -decay feeding of the 0⁺₂ state have been extracted. The present experimental results are compared to previous measurements and their impact on our understanding of the weak interaction is discussed.     

A 3-quasiparticle isomer in neutron-rich <Superscript>183</Superscript>Ta

Excited states in neutron-rich ¹⁸³Ta have been studied using a two-neutron transfer reaction of ¹⁸¹Ta(¹⁸O,¹⁶O) . In-beam -rays were measured in coincidence with scattered ions detected by a high-resolution E -E Si telescope for reaction channel selection. Previously known 1-quasiparticle bands are extended to higher spins, and several levels including a T _1/2 = 0.9(3) μs 3-quasiparticle isomer are identified.     

Manifestation of Intermolecular Interactions in the IR Spectra of 8-Azasteroids

We have investigated the intermolecular interactions of 8-aza-D-homogona-1,3,5(10),13-tetrane-12,17a-dione and 2,3-dimethoxy-8-azagone-1,3,5(10),13-tetran-12,17-dione with CHCl₃, binary solvents CHCl₃–CH₃OH, CCl₄–CHCl₃, and CCl₄–CH₃OH and also in the solid phase, which manifest themselves in the IR spectra. When the C=O groups of the studied 8-azasteroids form hydrogen bonding with the OH groups of alcohol, the frequencies (C=O) change insignificantly. We have found that they are higher than the corresponding frequencies in the IR absorption spectra of solid-phase samples, which is attributable not only to the effect of the medium but also to the possible shortened contacts of the C=O groups with the CH₃ and CH₂ groups of the molecules under study.     

Decay studies of <Superscript>214-216</Superscript>Ac by α- γ- γ-coincidences

The -decay fine structure of ²¹⁴Ac, ²¹⁵Ac and ²¹⁶Ac has been studied using the --coincidence technique. The nuclei were produced by ²⁰⁹Bi( ¹²C, xn)^221-xAc-reactions. Evaporation residues were separated in-flight from the primary beam using the velocity filter SHIP at GSI, Darmstadt. The separated nuclei were implanted into a position-sensitive 16-strip PIPS Si detector and their subsequent decays were measured. In these studies new and improved decay data for ^214-216Ac were obtained.     

The βdecay of 147Cs to 147Ba

The ^--decay of ¹⁴⁷Cs to ¹⁴⁷Ba has been studied by means of - and X-ray spectroscopy. A new level scheme of ¹⁴⁷Ba is significantly modified and extended in comparison to the one previously reported. The Advanced Time-Delayed (t) method has been applied to measure half-lives of the 46.2 and 85.4 keV levels in ¹⁴⁷Ba yielding T_1/2 of 510(80) ps and 370(100) ps, respectively. The lifetime results combined with the deduced internal conversion coefficients allowed to assign M1 multipolarity to three transitions. The B(M1) values obtained for the 39.2, 46.2 and 85.4 keV transitions range from 0.017 to 0.043 W.u. and represent typical B(M1) strength in the Ba-Er region. Model calculations using a shell correction approach with the axially deformed Woods-Saxon potential predict for ¹⁴⁷Ba an octupole deformed ground state with ₃ = 0.11.