Related papers: SpectAcLE: An Improved Method for Modeling Light E…
The light echo systems of historical supernovae in the Milky Way and local group galaxies provide an unprecedented opportunity to reveal the effects of asymmetry on observables, particularly optical spectra. Scattering dust at different…
In this paper we present and discuss the effects of scattered light echoes (LE) on the luminosity and spectral appearance of Type Ia Supernovae (SNe). After introducing the basic concepts of LE spectral synthesis, by means of LE models and…
Astronomical light echoes, the time-dependent light scattered by dust in the vicinity of varying objects, have been recognized for over a century. Initially, their utility was thought to be confined to mapping out the three-dimensional…
Light echoes, light from a variable source scattered off dust, have been observed for over a century. The recent discovery of light echoes around centuries-old supernovae in the Milky Way and the Large Magellanic Cloud have allowed the…
The spectra of type IIn supernovae indicate the presence of apre-existing slow, dense circumstellar wind (CSW). If the CSW extends sufficiently far from the progenitor star, then dust formation should occur in the wind. The light from the…
Scattered light echoes from variable and cataclysmic stars offer one of the most effective means to probe the structure and composition of circumtellar and interstellar media. I build a simple model of light-echo surface brightness by…
In general, Light Echoes (LE) are beautiful, rather academical and therefore unavoidably useless phenomena. In some cases, however, they can give interesting information about the environment surrounding the exploding star. After giving a…
Supernova flux and polarization spectra bring vital information on the geometry, physical conditions, and composition structure of the ejected matter. For some supernovae the circumstellar matter is also probed by the observed spectra. Some…
Light echoes are interesting because of the wealth of information they offer about their progenitors and the reflecting dust. Due to their faint surface brightnesses, difference imaging is necessary to separate most light echoes from the…
Spectral retrieval techniques are currently our best tool to interpret the observed exoplanet atmospheric data. Said techniques retrieve the optimal atmospheric components and parameters by identifying the best fit to an observed…
X-ray spectroscopy is a powerful technique for the analysis of the energy distribution of X-rays from astrophysical sources. It allows for the study of the properties, composition, and physical processes taking place at the site of…
The plasma opacity in stars depends mainly on the local state of matter (the density, temperature, and chemical composition at the point of interest), but in supernova ejecta it also depends on the expansion velocity gradient, because the…
Light passing near a black hole can follow multiple paths from an emission source to an observer due to strong gravitational lensing. Photons following different paths take different amounts of time to reach the observer, which produces an…
X-ray echo spectroscopy, a space-domain counterpart of neutron spin echo, is a recently proposed inelastic x-ray scattering (IXS) technique. X-ray echo spectroscopy relies on imaging IXS spectra, and does not require x-ray…
The spectrum of a supernova is a summation of numerous overlapping atomic line signatures. Consequently, empirical measurements are limited in application when compound features are assumed to be due to one or two spectral lines. Here I…
Optical spectroscopy is an important and widely used technique, for instance, to characterize new materials and to identify unknown compounds. Spectra are typically reported as a function of the wavelength of light, yet the information…
EChO is a dedicated mission to investigate exoplanetary atmospheres. When extracting the planetary signal, one has to take care of the variability of the hosting star, which introduces spectral distortion that can be mistaken as planetary…
When supernovae enter the nebular phase after a few months, they reveal spectral fingerprints of their deep interiors, glowing by radioactivity produced in the explosion. We are given a unique opportunity to see what an exploded star looks…
It is possible, for homogeneously broadened lines, to excite selectively the response signals, which are orders of magnitude narrower than the original lines. The new type of echo, which allows detecting such signals, and the formalism,…
We report on the discovery of the geometry producing the light echo emanating from Supernova 2006X, a nearby but underluminous Type Ia in M100 (= NGC 4321). This offers a rare chance to study the environment of a Type Ia supernova. Contrary…