Self-induced tunable transparency in layered superconductors

We predict a novel nonlinear electromagnetic phenomenon in layered superconducting slabs irradiated from one side by an electromagnetic plane wave. We show that the reflectance and transmittance of the slab can vary over a wide range, from nearly zero to one, when changing the incident wave amplitude. Thus changing the amplitude of the incident wave can induce either the total transmission or reflection of the incident wave. In addition, the dependence of the superconductor transmittance on the incident wave amplitude has an unusual hysteretic behavior with jumps. This remarkable nonlinear effect (self-induced transparency) can be observed even at small amplitudes, when the wave frequency $\omega$ is close to the Josephson plasma frequency $\omega_J$.Comment: 9 pages, 7 figure

Light Curve Models of Supernovae and X-ray spectra of Supernova Remnants

We compare parameters of well-observed type II SN1999em derived by M.Hamuy and D.Nadyozhin based on Litvinova-Nadyozhin (1985) analytic fits with those found from the simulations with our radiative hydro code Stella. The difference of SN parameters is quite large for the long distance scale. The same code applied to models of SN1993J allows us to estimate systematic errors of extracting foreground extinction toward SN1993J suggested by Clocchiatti et al. (1995). A new implicit two-temperature hydro code code Supremna is introduced which self-consistently takes into account the kinetics of ionization, electron thermal conduction, and radiative losses for predicting X-ray spectra of young supernova remnants such as Tycho and Kepler.Comment: 7 pages, 10 figures, Supernovae as Cosmological Lighthouses, Padua, June 16- 19, 2004, eds. M.Turatto et al., ASP Conference Serie

Early light curves for Type Ia supernova explosion models

Upcoming high-cadence transient survey programmes will produce a wealth of observational data for Type Ia supernovae. These data sets will contain numerous events detected very early in their evolution, shortly after explosion. Here, we present synthetic light curves, calculated with the radiation hydrodynamical approach Stella for a number of different explosion models, specifically focusing on these first few days after explosion. We show that overall the early light curve evolution is similar for most of the investigated models. Characteristic imprints are induced by radioactive material located close to the surface. However, these are very similar to the signatures expected from ejecta-CSM or ejecta-companion interaction. Apart from the pure deflagration explosion models, none of our synthetic light curves exhibit the commonly assumed power-law rise. We demonstrate that this can lead to substantial errors in the determination of the time of explosion. In summary, we illustrate with our calculations that even with very early data an identification of specific explosion scenarios is challenging, if only photometric observations are available.Comment: 15 pages, 14 figures, 3 tables, accepted for publication in MNRA