Laboratory set-up for X-ray diffraction at high pressures

We describe here a simple set-up for X-ray diffraction under high pressure using a diamond anvil cell employing a sealed tube. The set-up works in angular dispersive geometry and is built using rather common components that are available in a research laboratory. We show that using this set-up one can routinely acquire good-quality data for the determination of structural properties under pressure and the equations of state. Technical details are presented along with examples of experimental results for sodium chloride and LiV₂O₄.     

Possible High Power Laser Construction Using a New Discharge Type-Heated Cathode Discharge in the Copper Vapours Continuously Evaporated from the Anode

The possibility to build a high power copper laser using a new type of discharge – heated cathode discharge in the copper vapours continuously evaporated from a melted spot on the anode surface is analysed. From the experimental data on this new discharge type, the equivalent pressure of the copper atoms in the discharge space has been obtained. This pressure can be as high as 1 torr. The density of the power in the discharge volume is evaluated to be more than 1 kW/cm³.     

Morse inequalities, a function space integral approach

In this paper we prove the Morse inequalities in the non-degenerate and degenerate cases. Like the approach of J.-M. Bismut, ours is based on the idea suggested by Witten. In fact, if anything, our approach is closer to Witten's original idea than Bismut's.     

E -Theoretic Duality for Higher Rank Graph Algebras

We prove that there is a Poincaré type duality in E-theory between higher rank graph algebras associated with a higher rank graph and its opposite correspondent. We obtain an r-duality, that is the fundamental classes are in E^r. The basic tools are a higher rank Fock space and higher rank Toeplitz algebra which has a more interesting ideal structure than in the rank 1 case. The K-homology fundamental class is given by an r-fold exact sequence whereas the K-theory fundamental class is given by a homomorphism. The E-theoretic products are essentially pull-backs so that the computation is done at the level of exact sequences. Mathematics Subject Classification (2000): 46L80.     

Gamma-gamma angular correlations in125Te

Angular correlation measurements of the γ transitions coincident with 35.5 keV in¹²⁵Te were carried out with Ge(Li)-Si(Li) detectors. Mixing ratios for some of the transitions were determined.     

Coulomb excitation of levels in 143Nd and 145Nd

The low-lying states of ¹⁴³Nd and ¹⁵⁴Nd have been studied by means of Coulomb excitation with ¹⁶O and α-particles. Angular distribution measurements were carried out for some transitions in ¹⁴⁵Nd with 11.2 MeV α-particles. Level energy decay schemes and B(E2)↑ values were measured for two states in ¹⁴³Nd and for six states in ¹⁴⁵Nd. Some spin assignments have been established for the ¹⁴⁵Nd nucleus. ¹⁴³Nd and ¹⁴⁵Nd have been theoretically described by coupling one and three particles, respectively, to quadrupole vibrations, and rather good agreement with experiment was achieved.     

Minority carrier injection in relaxation semiconductors under illumination

The paper considers the injection of minority carriers into a relaxation semiconductor under uniform illumination. Steady state solutions have been computed, and used to assess the nature of the recovery process after cessation of the light. It is concluded that measurements of photoconductive decay do not in general lead to reliable lifetime estimates because, besides recombination, the movement of space charges is involved in the recovery.