An increasing amount of public interest in environmental monitoring programm.s.is being focused on the environmental impact of radiation arising from nuclear power operations and the corresponding detection of slight ...
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A detailed examination of the luminescent characteristics of variously pretreated heavily doped NaBr:Tl phosphors has been carried out. A prominent em.s.ion band at 420 nm exhibited by the phosphor is attributed to th...
A detailed examination of the luminescent characteristics of variously pretreated heavily doped NaBr:Tl phosphors has been carried out. A prominent em.s.ion band at 420 nm exhibited by the phosphor is attributed to the electronic transitions within Tl+ ion perturbed by the presence of another Tl+ ion occupying nearest neighbour alkali ion site, the centre so formed being known as dimer. It is rather surprising that the dimers are conspicuous by their absence in heavily doped NaCl:Tl phosphors. This aspect of the result is discussed on the basis of the relative sizes of the ions in the phosphors.
The present review article contains various applications of Thermoluminescence. The phenomena of thermoluminescence (TL) or thermally stimulated luminescence (TsL) and optically stimulated luminescence (OsL) are widel...
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The bombardment of energetic ions on polymer membranes will produce the loosely bound passage in the membrane structure due to the energy loss. The swift Heavy Ions (sHI) creates the latent tracks of several nm.s.rrou...
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The deformation induced thermoluminescence of NaCl:Ca(T) exhibitsmarked changed in its pattern when subjected to thermal cycling. This issuggested to be due to the break-up of the impurity — vacancy dipole aggregat...
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The deformation induced thermoluminescence of NaCl:Ca(T) exhibitsmarked changed in its pattern when subjected to thermal cycling. This issuggested to be due to the break-up of the impurity — vacancy dipole aggregates and subsequent rearrangement of the free dipoles.
Optical and structural investigations of antimony-doped cadmium.s.lphide thin films prepared by a modified chemical deposition process are described. The samples were prepared in an aqueousmedium at a deposition temp...
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Optical and structural investigations of antimony-doped cadmium.s.lphide thin films prepared by a modified chemical deposition process are described. The samples were prepared in an aqueousmedium at a deposition temperature of 85+/-2 degrees C and a pH of around 8.5. The samples were doped with various concentrations of sb3+ in the concentration range 0.005-1 wt.%. measurements of the absorption coefficient in the energy range 1.6-3.5 eV for both Cds and Cds:sb crystalline thin films have been carried out. A careful analysis of the absorption coefficients indicated the crystalline character of the samplesstudied;a similar diagnosis was obtained from the X-ray and sEm analyses. The absorption coefficient is of the order of 10(4) cm(-1), and the optical energy bandgap decreases with increasing doping concentration, typically from 2.47 to 1.7 eV. The absorption edge shifts towards the higher-wavelength side and becom.s.broader as the doping concentration is increased. The samples are polycrystalline, and the crystallinity increases after doping up to a 0.075 wt.% doping level and decreases thereafter. In both cases the samples consist of phases of cubic and hexagonal structures. Additional peaks corresponding to sb2s3 orthorhombic phases and some other small peaks due to excess Cd and s have also been observed.
We demonstrate theoretically and experimentally self-quenching of the fundamental semiconductor laser frequency fluctuations to a level that is orders of magnitude below the schawlow-Townes limit for a solitary laser....
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We demonstrate theoretically and experimentally self-quenching of the fundamental semiconductor laser frequency fluctuations to a level that is orders of magnitude below the schawlow-Townes limit for a solitary laser. It isshown that the main operative mechanism is the combined action of a frequency-dependent internal loss and amplitude-to-phase coupling. The internal frequency-dependent loss is introduced by means of spectrally narrow external optical feedback, which provides a strong frequency-dependent dispersion. Linewidth reduction by a factor of 2 x 10(3) is demonstrated by using a narrow Doppler-free Faraday resonance in Cs vapor.
The framework of a phenomenological quark-antiquark potential（Coulomb plus linear confinement）model with a Gaussian wave function is used for detailed study of m.s.es of the ground, orbitally and radially excited st...
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The framework of a phenomenological quark-antiquark potential（Coulomb plus linear confinement）model with a Gaussian wave function is used for detailed study of m.s.es of the ground, orbitally and radially excited states of heavy-light Qq^-,（Q=c,q=u/d,s） m.s.ns. We incorporate a O（1/m） correction to the potential energy term and relativistic corrections to the kinetic energy term of the Hamiltonian. The spin-hyperfine, spin-orbit and tensor interactions incorporating the effect of mixing are employed to obtain the pseudoscalar, vector, radially and orbitally excited state m.s.n m.s.es. The Regge trajectories in the（J,m^2） and（nr,m^2） planes for heavy-light m.s.ns are investigated with their corresponding parameters. Leptonic and radiative leptonic decay widths and corresponding branching ratios are computed. The mixing parameters are also estimated. Our predictions are in good agreement with experimental results as well as lattice and other theoretical models.
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