Related papers: The 3-D ionization structure of the planetary nebu…
We present a detailed analysis of the new planetary nebula (PN) IPHASX J193718.6+202102 using deep imaging and intermediate- and high resolution spectroscopy that are interpreted through morpho-kinematic and photoionisation modelling. The…
The WFPC2 camera aboard the HST was used to obtain images of the planetary nebula BD+30 3639 at two epochs separated by 5.663 years. The expansion of the nebula in the H-alpha and [N II] bands has been measured using several methods.…
Spectroscopic measurements of emission line ratios and velocities are presented for ionized gas across the central plane of NGC 55, a late-type galaxy in the Sculptor group. The low metallicity in NGC 55 leads to relatively low line ratios…
The Apollo-type near-Earth asteroid (155140) 2005 UD is thought to be a member of the Phaethon-Geminid meteor stream Complex (PGC). Its basic physical parameters are important for unveiling its origin and its relationship to the other PGC…
In this paper we present an analysis of the physical and chemical conditions of the planetary nebula NGC 40 through spatially-resolved spectroscopic maps. We also introduce a new algorithm --2D_NEB-- based on the well-established IRAF…
This paper discusses the location of a sample of planetary nebulae on the HR diagram. We determine the internal velocity fields of 14 planetary nebulae from high-resolution echelle spectroscopy, with the help of photoionization models. The…
A present prevailing open problem planetary nebulae research, and photoionized gaseous nebulae research at large, is the systematic discrepancies in ionic abundances derived from recombination and collisionally excited lines in many H II…
We present general properties of ionized hydrogen (HII) bubbles and their growth based on a state-of-the-art large-scale (100 Mpc/h) cosmological radiative transfer simulation. The simulation resolves all halos with atomic cooling at the…
The reionization of intergalactic hydrogen has received intense theoretical scrutiny over the past two decades. Here, we approach the process formally as a percolation process and phase transition. Using semi-numeric simulations, we…
New results on the radio-quiet type 2 quasar known as the Teacup galaxy (SDSSJ1430+1339) based on the long-slit and 3D spectroscopic data obtained at the Russian 6-m telescope are presented. The ionized gas giant nebula extending up to r=56…
A one dimensional radiative transfer code is developed to track the ionization and heating pattern around the first miniquasars and Population III stars. The code follows the evolution of the ionization of the species of hydrogen and helium…
Observations of infrared fine-structure lines provide direct information on the metallicity and ionization structure of HII regions and indirectly on the hardness of the radiation field ionizing these nebulae. We have analyzed a sample of…
We use the full broad-band XMM-Newton EPIC data to examine the X-ray spectrum of the nearby Seyfert 2 galaxy NGC 1068, previously shown to be complex with the X-ray continuum being a sum of components reflected/scattered from cold (neutral)…
This study continues our investigation of early-type binaries using high-precision broad-band polarimetry, focusing on HD 165052, a massive O+O-type binary in the young cluster NGC 6530. Our aim was to monitor linear polarization variations…
The central region of NGC 1068 is one of the closest and most studied Active Galactic Nucleus. It is known to be of type 2, meaning that its accretion disk is obscured by a large amount of dust and gas. The main properties of the obscuring…
We present new calculations of the inhomogeneous process of cosmological reionization by carefully following the radiative transfer in pre-computed hydrodynamical simulations of galaxy formation. These new computations represent an…
We map the optical and near-infrared (NIR) emission-line flux distributions and kinematics of the inner 320$\times$535pc$^2$ of the elliptical galaxy NGC1052. The integral field spectra were obtained with the Gemini Telescope using the…
We present the results of a series of observations of the near- and mid-infrared polarisation properties of the Seyfert 2 galaxy NGC1068. Our data agree well with previously published results in showing the need for a separate polarisation…
We present VIMOS integral field spectroscopy of the brightest radio-quiet QSO on the southern sky HE 1029-1401 at a redshift of z=0.086. Standard decomposition techniques for broad-band imaging are extended to integral field data in order…
We present results from deep imaging linear and circular polarimetry of the massive star-forming region NGC 6334- V. These observations show high degrees of circular polarization (CP), as much as 22 % in the Ks band, in the infrared nebula…