Related papers: The Galactic Extinction Toward GRB 970228 and Its …
We find that the local galactic extinction towards the field of gamma-ray burst GRB970228 is $A_V=1.09^{+0.10}_{-0.20}$, which implies a substantial dimming and change in the spectral slope of the intrinsic GRB970228 afterglow. We measure a…
We determine the local galactic extinction towards the field of gamma-ray burst GRB970228 using a variety of methods. We develop a maximum likelihood method for measuring the extinction by comparing galaxy counts in the field of interest to…
We report on observations of the fading optical counterpart of the gamma-ray burst GRB 970228, made with the Hubble Space Telescope STIS CCD approximately six months after outburst and with the HST/NICMOS and Keck/NIRC approximately one…
We carefully analyze the WFPC2 and STIS images of GRB970228. We measure magnitudes for the GRB970228 point source component in the WFPC2 images of $V=26.20^{+0.14}_{-0.13}$, $I_c=23.94^{+0.10}_{-0.09}$ and $V=26.52^{+0.16}_{-0.18}$,…
We report on observations of the fading optical counterpart of the gamma-ray burst GRB 970228, made on 4~September~1997 using the STIS CCD on the Hubble Space Telescope. The unresolved counterpart is detected at V=28 +/- 0.25, consistent…
We develop the ``simulated extinction method'' to measure average foreground Galactic extinction from field galaxy number-counts and colors. The method comprises simulating extinction in suitable reference fields by changing the isophotal…
We present an analysis of the dust optical properties at large scale, for the whole galactic anticenter hemisphere. We used the 2MASS Extended Source Catalog to obtain the total reddening on each galaxy line of sight and we compared this…
The dust extinction of gamma-ray bursts (GRBs) host galaxies, containing important clues to the nature of GRB progenitors and crucial for dereddening, is still poorly known. Here we propose a straightforward method to determine the…
We have studied the interstellar extinction in a field of ~3' x 3' at the core of the 30 Doradus nebula, including the central R136 cluster, in the Large Magellanic Cloud. Observations at optical and near-infrared wavelengths, obtained with…
Extinction in ultraviolet is much more significant than in optical or infrared, which can be very informative to precisely measure the extinction and understand the dust properties in the low extinction areas. The high Galactic latitude sky…
The accurate position determination of GRB 970228 by the Beppo/SAX Satellite led to the discovery of a fading X-ray and optical counterparts of the burst. About a month after the GRB event the proper motion of the ejecta was detected and…
We probe the dust extinction through the foreground disk of the overlapping galaxy pair UGC 5041 by analyzing B,I, and H band images. The inclined foreground disk of this infrared-selected pair is almost opaque in B at a projected distance…
We present multi-color light-curves of the optical afterglow of GRB 000926. Beginning ~1.5 days after the burst, the light-curves of this GRB steepen measurably. The existence of such achromatic breaks are usually taken to be an important…
We present a new two-dimensional (2D) map of total Galactic extinction, $A_\mathrm{V}$, across the entire dust half-layer from the Sun to extragalactic space for Galactic latitudes $|b|>13$ deg, as well as a three-dimensional (3D) map of…
Using a sample of gamma-ray burst (GRB) afterglows detected by both the X-Ray and the UV/Optical Telescopes (XRT and UVOT) on Swift, we modelled the spectral energy distributions (SEDs) to determine gas column densities and dust extinction…
We report on observations of the field of GRB~970508 made in early August 1998, 454 days after outburst, with the STIS CCD camera onboard the Hubble Space Telescope. The images, taken in open filter (50CCD) mode, clearly reveal the presence…
We report optical extinction properties of dust for a sample of 26 early-type galaxies based on the analysis of their multicolour CCD observations. The wavelength dependence of dust extinction for these galaxies is determined and the…
We present and analyze spatially-resolved maps for the observed $V$- and $g$-band to 3.6$\mu$m flux ratios and the inferred dust extinction values, $A_V$, for a sample of 257 nearby NGC and IC galaxies. Flux ratio maps are constructed using…
For aspherical interstellar dust grains aligned with their short axes preferentially parallel to the local magnetic field, the amount of extinction per grain is larger when the magnetic field is along the line of sight and smaller when in…
We explore the extinction properties of the dust in the distant universe through the afterglows of high-redshifted GRBs based on the "Drude" model which, unlike previous studies, does not require a prior assumption of template extinction…