Non-gray radiative transfer

The normal-mode-expansion technique is used to establish the solution of the Milne problem basic to a generalized equation of radiative transfer. The non-gray model used includes the effects of absorption, scattering and losses due to photo-electric ionizations and collisions of the second kind. Accurate numerical results are presented for such physical quantities as the extrapolation distance, the integrated Planck function and the angular distribution of the exit intensity for selected values of the basic parameters.     

Theoretical analysis of atom formation-time curves for the HGA-74 furnace—II: Evaluation of the atomisation mechanisms Mn,Cr and Pb

In this study, a novel approach was used in the evaluation of the atomisation mechanisms of Mn, Cr and Pb. The atomisation process was considered as first order kinetics. The effect of the heating rates, chemical form of analyte, gas flow and analyte mass on the atomisation mechanisms of these elements were investigated. The major pathways leading to gaseous atoms have been found to be the thermal dissociation of the metal oxide and reduction of the metal oxide followed by the vaporisation of free metal.     

Analytical expression for the flux density around a disk-shaped source emitting omnidirectionally with second order radial dependence,in nondispersive media

Computationally tractable expression is presented for the flux density distribution produced in nondispersive media by a diskshaped source, whose local emissivity is omnidirectional and governed by a radial gradient dependence of second order binomial type.     

Pre-equilibrium emission in neutron induced reactions on54,56Fe

The experimentally well known (n, p), (n, α) and (n, 2n) reaction excitation functions, from threshold to 20 MeV incident energy, and neutron and proton emission spectra at 14.8 MeV from^54,56Fe targets are calculated in the frame of the Geometry-Dependent Hybrid pre-equilibrium emission model, including angular momentum and parity conservation, and the Hauser-Feshbach statistical model. Use of a consistent statistical model parameter set enables the validation of the pre-equilibrium emission model. Moreover, an enhanced pre-equilibrium emission from higher spin composite system states, associated with higher incoming orbital momenta, has been evidenced. Higher orbital momenta involved also in the emergent channels of the process are suggested by calculations of the residual nuclei level populations.     

Estimations for the characteristic values of a Sturm-Liouville problem

Zeitschrift für angewandte Mathematik und Physik - We consider a particular Sturm-Liouville problem, with boundary conditions containing the characteristic values. This problem governs the...     

Radiative transfer in an isotropically scattering two-region slab with reflecting boundaries

The problem of radiative heat transfer in an absorbing, emitting, isotropically scattering two-layer slab with diffusely and specularly reflecting boundaries is solved by the F_N method and results are presented for the transmissivity and reflectivity of the slab.     

Superconformal anomalies and the effective lagrangian for pure supersymmetric QCD

We discuss the extent to which the superconformal anomalies constrain the effective lagrangian for pure N = 1 Yang-Mills theory. Assuming that the order parameter describing the model is a single chiral superfield (and allowing its derivatives) we find a larger class of possible models than had been previously noted. We give a detailed analysis of a particularly interesting example and find that it leads to the possibility of spontaneous breakdown of supersymmetry. Thus we conclude that the anomaly constraints by themselves are not sufficient to protect supersymmetry. Some unusual features which seem characteristic of such higher derivative theories are noted. A number of related topics, including the question of gluon condensation, are discussed.     

Spin-parity,lifetime and magnetic moment of a short-lived isomeric state in 118Sb

A 3⁺ isomeric state has been identified in ¹¹⁸Sb by pulsed-beam time-differential γ-ray measurements following 4the ¹¹⁸Sn(p, n) and ¹¹⁵In(α, n) reactions. The results of these measurements are: $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 20.6 ± 0.6μ, E}{}_{\mathrm{\gamma }}\text{= 54.4 ± 0.5 keV, α}{}_{\mathrm{<mtext>K</mtext>}}\text{= 8.3 ± 1.0}$ and μ = +2.61 ± 0.05 n.m.     

Normkonvergenz von Fourierreihen in rearrangement invarianten Banachräumen

This paper studies rearrangement invariant Banach spaces of 2π-periodic functions with respect to norm convergence of Fourier series. The main result is that norm convergence takes place if and only if the space is an interpolation space of $\text{(}\text{L}{}^{\mathrm{p\prime }}\text{(T),}\text{L}{}^{\mathrm{p}}\text{(T)), 1 < p < 2,}\text{1}\text{p′}\text{+}\text{1}\text{p}\text{= 1}$, and L^p′(T) is dense in it (compare Satz 2.8). Since norm convergence and continuity of the conjugation operator are closely connected (compare Satz 2.2), this is achieved by a careful examination of this operator similar to that of D. W. Boyd for the Hilbert transform on the whole real axis. Finally, there are applications to Orlicz and Lorentz spaces.