Related papers: The Variable Diffuse Continuum Emission of Broad L…
As part of an extensive multi-wavelength monitoring campaign, the International Ultraviolet Explorer satellite was used to observe the broad-line radio galaxy 3C 390.3 during the period 1994 December 31 to 1996 March 5. Spectra were…
We investigate the properties of the extinction curve in the rest-frame UV for a sample of 34 UV-luminous galaxies at 2 < z < 2.5, selected from the FORS Deep Field (FDF) spectroscopic survey. A new parametric description of the rest-frame…
Quasars show a remarkable degree of atomic emission line-broadening, an observational feature which, in conjunction with a radial distance estimate for this emission from the nucleus is often used to infer the mass of the central…
We use a sample of 4178 Lyman break galaxies (LBGs) at z = 3, 4 and 5 in the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra Deep Survey (UDS) field to investigate the relationship between the observed slope of the stellar continuum emission…
We summarize results of the analysis of the optical variability of the continuum and emission-line fluxes in the 3C390.3 nucleus during 1992-2014. The [OIII]5007 flux increases monotonically by $\approx$30 per cent in 2003-2014. The narrow…
We derive a mean attenuation curve out to the rest-frame extreme ultraviolet (EUV) for 'BAL dust' - the dust causing the additional extinction of active galactic nuclei (AGNs) with broad absorption lines (BALQSOs). In contrast to the…
We analyze the ratios of the broad hydrogen Balmer emission lines (from H\alpha to H\epsilon) in the context of estimating the physical conditions in the broad line region (BLR) of active galactic nuclei (AGN). The Balmer emission lines are…
JWST has enabled the detection of the UV continuum of galaxies at z>10, evidencing a population of extremely blue, potentially dust-free galaxies. Interpreting the UV spectra of galaxies as they redden is complicated by the well-known…
We study the expected properties of starbursts in order to provide the point of reference for interpretation of high-z galaxy surveys and of very metal-poor galaxies. We concentrate mainly on the UV characteristics such as the ionizing…
NGC 5548 has been intensively monitored by the AGN Space Telescope and Optical Reverberation Mapping collaboration. Approximately after half of the light curves, the correlation between the broad emission lines and the lag-corrected…
CONTEXT: The Virgo direction has been observed at many wavelengths in the recent years, in particular in the ultraviolet with GALEX. The far ultraviolet (FUV) diffuse light detected by GALEX bears interesting information on the large scale…
The profiles of the broad emission lines of active galactic nuclei (AGNs) and the time delays in their response to changes in the ionizing continuum ("lags") give information about the structure and kinematics of the inner regions of AGNs.…
We investigate the variability of the continuum and broad lines in QSO spectra (particularly in the H$\beta$ line and continuum at $\lambda$ 5100 \AA ) caused by microlensing of a diffuse massive structure (like an open star cluster). We…
Variable continuum emission from AGN can be used to probe the structure of their accretion disks via reverberation mapping. Assuming a variable, hot inner light source irradiates the surrounding accretion disk, time delays between different…
A gamma ray burst with strong optical-UV emission occuring in a molecular cloud will photodissociate H2, photoionize H2, H, and He, and destroy dust grains. We model these processes, including time-dependent radiative transfer in both…
We present our analysis of UV attenuation by internal dust of a large sample (N=906 galaxies) of Lyman Break Galaxies (LBGs). Using spectral energy distributions (SEDs) from the P\'EGASE galaxy spectral evolution model we apply dust…
We present results from intensive (x3 daily), three-month-long X-ray, UV and optical monitoring of the bright Seyfert active galactic nucleus (AGN) MCG+08-11-11 with Swift, supported by optical-infrared ground-based monitoring. The 12…
PBC J2333.9-2343 is a peculiar active nucleus with two giant radio lobes and a weak blazar-like nucleus at their center. In the present work we show new optical, UV, and X-ray data taken from the San Pedro M\'artir telescope, the New…
The so-called ultraviolet (UV) upturn of elliptical galaxies is a phenomenon characterised by the up-rise of their fluxes in bluer wavelengths, typically in the 1,200-2,500A range. This work aims at estimating the rate of occurrence of the…
The similarity of quasar line spectra has been taken as an indication that the emission line clouds have preferred parameters, suggesting that the environment is subject to a fine tuning process. We show here that the observed spectrum is a…