Related papers: Observational constraints on the ERE interpretatio…
The ongoing quest to identify molecules in the interstellar medium by their electronic spectra in the visible region is reviewed. Identification of molecular absorption is described in the context of the elucidation of the carriers of the…
This review addresses the current observational status of the Baldwin Effect (BE), an empirical anti-correlation between emission line equivalent width and source luminosity for active galactic nuclei. We provide a brief history of the BE,…
The condition of radio emission is proposed, on the base of which the theory of themal radio emission for gaseous disk is developed. This theory explains the radio emission spectra of known types of extended radio sources, located beyond…
Interdependencies between experimental spectra, representing line or plane projections of electronic densities, are derived from their consistency and symmetry conditions. Some additional relations for plane projections are obtained by…
The aim of this article is to demonstrate the useful role that can be played by spectropolarimetric observations of young and evolved emission line stars that analyse the linearly polarized component in their spectra. At the time of…
Recent work (Corradi et al. 2015, Jones et al. 2016) has shown that the phenomenon of extreme abundance discrepancies, where recombination line abundances exceed collisionally excited line abundances by factors of 10 or more, seem to be…
We discuss the present knowledge about the Spectral Energy Distributions (SEDs) of blazars within a unified approach emphasizing overall similarities. The properties of the average SEDs of different samples of blazars suggest that more…
IR and mm-wave emission from Herbig Ae/Be stars has produced conflicting conclusions regarding the dust geometry in these objects. We show that the compact dimensions of the mm-wave emitting regions are a decisive indication for disks. But…
The absorption of gamma-rays in the intergalactic medium due to the EBL (Extragalactic Background Light) causes the observed blazar spectrum to be fainter and softer than their intrinsic state. It could thus be expected to see an effective…
Extended emission (EE) is a high-energy, early time rebrightening sometimes seen in the light curves of short gamma-ray bursts (GRBs). We present the first contiguous fits to the EE tail and the later X-ray plateau, unified within a single…
A general energy dispersion relation is developed for metamaterials having the negative-refraction (NR) property. It is shown that absorption effects are involved with NR phenomena, and the conditions under which NR occurs are discussed.…
Recently proposed correlations between the energetics of Gamma-Ray Bursts (GRB) and their spectral properties, namely the peak energy of their prompt emission, are found to account for the observed fluence distribution of all `bright' BATSE…
We present the results of a near-infrared narrowband imaging survey of planetary nebulae. Objects were selected in a way that complements similar surveys done at visible and near-infrared wavelengths. No new detections of molecular hydrogen…
Extrasolar planets are a natural extension of the interacting binaries towards the companions with very small masses and similar tools might be used to study them. Unfortunately, the generally accepted treatment of the reflection effect in…
We conduct 2D numerical simulations of jets expanding into the slow wind of asymptotic giant branch stars. We show that the post-shock jets' material can explain the observed extended X-ray emission from some planetary nebulae (PNs). Such…
The energy spectrum of cosmic rays (CR) exhibits power-like behavior with a very characteristic "knee" structure. We consider a possibility that such a spectrum could be generated by some specific nonstatistical temperature fluctuations in…
The Sun was recently predicted to be an extended source of gamma-ray emission, produced by inverse-Compton scattering of cosmic-ray electrons with the solar radiation. The emission was predicted to contribute to the diffuse extragalactic…
We outline some of the highlights of the scientific case for the advancement of stellar high energy physics using the Line Emission Mapper X-ray Probe ({\it LEM}). The key to advancements with LEM lie in its large effective area -- up to…
We discuss the role of the electron temperature in abundance determinations in ionized nebulae (planetary nebulae and giant HII regions). We show that, even when observations provide a direct estimate of Te, abundance determinations may…
(Abridged) Planetary nebulae (PNe) around Wolf-Rayet [WR] central stars ([WR]PNe) constitute a particular photoionized nebula class that represents about 10% of the PNe with classified central stars. We analyse deep high-resolution…