In the present work, the non-spherical grain characteristics of comet Halley are analysed using the T-matrix method at λ= 0.365,0.485 and 0.684μm respectively. In order to analyse the polarisation data of comet Halley, the dust size distribution function derived by Das et al. (2004) for comet Halley is used in the present work. The size range of the grains is taken to be 0.01μm≤ s ≤ 3μm. Using ...

New developments in wavefront and polarisation control for ultrashort-pulse laser microprocessing are presented. Two Spatial Light Modulators are used in combination to structure the optical fields of a picosecond-pulse laser beam, producing vortex wavefronts and radial or azimuthal polarisation states. Demonstration of multiple first-order beams with vortex wavefronts and radial or azimuthal p...

We present a method for estimating surface height directly from a single polarisation image simply by solving a large, sparse system of linear equations. To do so, we show how to express polarisation constraints as equations that are linear in the unknown depth. The ambiguity in the surface normal azimuth angle is resolved globally when the optimal surface height is reconstructed. Our method is...

We present a model for ab-initio calculations of the interaction of two-electron atoms and molecules with few-cycle pulses of intense linearly polarised Ti:sapphire laser radiation. In the model the center-of-mass motion of the two electrons is restricted along the polarisation direction axis, while its relative coordinate and, hence, the electron correlation is retained in its full dimensional...

In this paper we present a novel image-based 3D surface reconstruction technique that incorporates reflectance, polarisation, and defocus information into a variational framework. Our technique is especially suited for the difficult task of 3D reconstruction of rough metallic surfaces. An error functional composed of several error terms related to the measured reflectance and polarisation prope...

Compact analytic expressions have been obtained for the first order perturbative QCD corrections to the inclusive spectra of the leptons in the semileptonic decays of polarised heavy quarks. Charmed and beautiful Λ baryons from Z decays can be viewed as sources of highly polarised charm and bottom quarks. Charged leptons and neutrinos from Λb and Λc decays can be used in the polarisation studie...

The association of all three soft gamma-ray repeaters (SGRs) with supernova remnants has established that SGRs are young neutron stars, and has given us a starting point for detailed modeling. One of the most popular classes of models involves strongly magnetised neutron stars, with surface dipole fields B ∼ 10 − 10 G. In such strong magnetic fields, many otherwise negligible processes can play...

The polarisation of x-ray photons can be determined by measuring the direction of emission of a K-shell photoelectron. Effective exploitation of this effect below 10 keV would allow development of a highly sensitive x-ray polarimeter dedicated in particular to x-ray astronomy observations. Only with the advent of finely segmented gas detectors was it possible to detect polarisation sensitivity ...

When unpolarised light is reflected from a smooth dielectric surface, it is spontaneously partially polarised. This process applies to both specular and diffuse reflection, although the effect is greatest for specular reflection. This paper is concerned with exploiting this phenomenon by processing images of smooth dielectric objects to recover surface normals and hence height. The paper presen...