相关论文: Sub-surface alteration and related change in refle…
We use helioseismic data obtained over two solar cycles to determine whether there are changes in the near-surface shear layer (NSSL). We examine this by determining the radial gradient of the solar rotation rate. The radial gradient itself…
Processes such as the solar wind sputtering and micrometeorite impacts can modify optical properties of surfaces of airless bodies. This explains why spectra of the main belt asteroids, exposed to these `space weathering' processes over…
We present experimental and theoretical results for the variation of the O 1s intensity from a NiO(001) surface as the excitation energy is varied through the Ni 2p1/2,3/2 absorption resonances, and as the incidence angle of the radiation…
The energy balance and climate of planets can be affected by the reflective properties of their land, ocean, and frozen surfaces. Here we investigate the effect of host star spectral energy distribution (SED) on the albedo of these surfaces…
The interaction of high-energy electrons and X-ray photons with soft semiconductors such as halide perovskites is essential for the characterisation and understanding of these optoelectronic materials. Using nano-probe diffraction…
We present new grids of transmission spectra for hot-Jupiters by solving the multiple scattering radiative transfer equations with non-zero scattering albedo instead of using the Beer-Bouguer-Lambert law for the change in the transmitted…
We analyse RXTE/PCA X-ray spectra of the binary X-ray pulsar Her X-1/HZ Her during short high state and one binary orbit in the preceding low state, just before short high turn-on. The spectrum is well described by two continuum components…
It is shown that the transparency of opaque material with negative permittivity exhibits resonant behavior. The resonance occurs as a result of the excitation of the surface waves at slab boundaries. Dramatic field amplification of the…
ZnO nanoparticles (NP) of size less than around 20 nm inside a chamber exhibits complete reduction in their visible photoluminescence (PL) intensity when partial pressure of oxygen in the surrounding gaseous environment is decreased by…
Noble metal nanoparticles exhibit localized plasmon resonance modes that span the visible and near-infrared spectral ranges and have many applications. Modifying the size, shape, and composition of the nanoparticles changes the number of…
Frequency shifts, radiative decay rates, the Ohmic loss contribution to the nonradiative decay rates, fluorescence yields, and photobleaching of a two-level atom radiating anywhere inside or outside a complex spherical nanoshell, i.e. a…
The dependence of surface-enhanced Raman scattering (SERS) spectra on the precise axial position of the laser focus relative to a solid nanostructured substrate has received little to no attention in the literature. Here we show this…
We present detailed broadband UV/optical to X-ray spectral variability of the Seyfert 1 galaxy 1H 0419-577 using six XMM-Newton observations performed during 2002-2003. These observations covered a large amplitude variability event in which…
X-ray observations of active galactic nuclei (AGN) show variability on timescales ranging from a few hours up to a few days. Some of this variability may be associated with occultation events by clouds in the broad line region. In this…
In the present Ph.D. Thesis we report an experimental investigation on the effects of gamma- and beta-ray irradiation and of subsequent thermal treatment on many types of a-SiO2 materials, differing in the production methods, OH- and…
An influence of pass-through optics on femtosecond laser pulse filamentation in ambient air is analyzed for the first time both experimentally and numerically. Propagation of high-power femtosecond laser pulse through solid optical elements…
Transmission spectra are differential measurements that utilize stellar illumination to probe transiting exoplanet atmospheres. Any spectral difference between the illuminating light source and the disk-integrated stellar spectrum due to…
Time of Flight Secondary Ion Mass Spectroscopy, X-Ray Photoelectron Spectroscopy, in situ Photo-Current Spectroscopy and electrochemical analysis were combined to characterize the physicochemical alterations induced by electrochemical…
Tailoring the physical properties of complex materials for targeted applications requires optimizing the microstructure and crystalline defects that influence electrical and thermal transport, and mechanical properties. Laser surface…
Transparent materials do not absorb light but have profound influence on the phase evolution of transmitted radiation. One consequence is chromatic dispersion, i.e., light of different frequencies travels at different velocities, causing…