Extinction properties of the X-ray bright/optically  faint
afterglow of GRB 020405

Stratta, G.; Perna, Rosalba; Lazzati, Davide; Fiore, F.; Antonelli, L. A.; Conciatore, M. L.

doi:10.1051/0004-6361:20053302

Cited by 41 publications

(43 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[23]found that for GRB 051022 a lower limit of Ay fv AAMag was needed, which implies that at least in some GRBs the extinction Ay is rather large. The extinction curve derived in our work is flat, almost independent of wavelength.This result is in good agreement with other works fitting the SEDs of these bursts [33,16]. In particular, Perley et al (2007) found that for GRB 061126 the extinction curve is gray.…”

Section: Discussionsupporting

confidence: 92%

Determining the Dust Extinction of Gamma-ray Burst Host Galaxies: A Direct Method Based on Optical and X-ray Photometry

Wei

2008

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. We propose a straightforward method to determine the extinction of GRB host galaxies by comparing the observed optical spectra to the intrinsic ones extrapolated from the X-ray spectra.The derived extinction curves are gray and do not resemble any extinction curves of local galaxies. The amount of extinction is rather large. We model the derived extinction curves in terms of the silicate-graphite interstellar grain model and obtain the dust size distribution skewed to large grains. We determine, for the first time, the local dust-to-gas ratios of GRB host galaxies using the model-derived dust parameters and the hydrogen column densities determined from X-ray absorptions.

show abstract

Section: Discussionsupporting

confidence: 92%

Determining the Dust Extinction of Gamma-ray Burst Host Galaxies: A Direct Method Based on Optical and X-ray Photometry

Wei

2008

AIP Conference Proceedings

View full text Add to dashboard Cite

show abstract

“…Gray dust has been invoked by a number of authors (e.g., Savaglio et al 2003;Savaglio & Fall 2004;Stratta et al 2004Stratta et al , 2005 to account for the small ratios of extinction and/or reddening (derived from fitting the afterglow SEDs) to H column densities (determined from X-ray or Lya absorption) of GRB hosts, which are usually smaller than that of the MW by a factor of ∼10-100 (Galama & Wijers 2001;Š imon et al 2001;Hjorth et al 2003;Vreeswijk et al 2004). 7 Gray dust could be created by (1) the preferential destruction of small grains by the intense UV and X-ray radiation from the GRB (Waxman & Draine 2000;Fruchter et al 2001;Perna et al 2003) in the immediate GRB environment, say, within ∼10-20 pc of the burster (Hjorth et al 2003;Savaglio et al 2003;Stratta et al 2005), and (2) the growth of dust through coagulation (which also leads to the depletion of small grains) in the high-density environments such as the cores of star-forming regions harboring GRB events (Maiolino et al 2001;Stratta et al 2004). Both mechanisms naturally lead to a dust size distribution skewed toward large grains, producing an extinction curve weakly dependent on wavelength.…”

Section: Discussionmentioning

confidence: 99%

Dust Extinction of Gamma-Ray Burst Host Galaxies: Identification of Two Classes?

Chen

Wei

2006

ApJ

View full text Add to dashboard Cite

Dust in the host galaxies of gamma-ray bursts (GRBs) dims and reddens their afterglow spectra. Knowledge of the nature of this dust is crucial for correcting for extinction, providing clues to the nature of GRB progenitors, and probing the interstellar medium of high-redshift galaxies as well as the nature of cosmic dust when the universe was much younger and galaxies were much less evolved. The dust and extinction properties of GRB host galaxies are still poorly known. Unlike previous work, we derive in this Letter the extinction curves for 10 GRB host galaxies without a priori assumption of any specific extinction types (such as those of the Milky Way or Small/Large Magellanic Clouds). It is found that there appear to exist two different types of extinction curves: one is relatively flat and gray, and the other displays a steeper dependence on inverse wavelength, closely resembling that of the Milky Way but with the 2175 feature removed.

show abstract

“…Such high column densities have been detected only in high z GRBs so far (GRB050904 at z = 6.29 and and GRB060510B at z = 4.9). These column densities imply a huge extinction of the rest-frame UV light, if dust with properties similar to those in the Galaxy, the SMC, or even for a dust with a grain distribution strongly shifted toward large grain sizes (Stratta et al 2004(Stratta et al , 2005 would be associated to the X-ray absorbing gas. The simple detection of the bright optical and near infrared afterglow of this GRB (Tagliaferri et al 2005;Haislip et al 2006;Boer et al 2006) implies peculiar dust properties (Campana et al 2006b;Stratta et al 2007).…”

Section: Selection Effects At Workmentioning

confidence: 99%

Selection effects shaping the gamma ray burst redshift distributions

Fiore¹,

Guetta²,

Piranomonte³

et al. 2007

A&A

Self Cite

View full text Add to dashboard Cite

Aims. Long gamma ray bursts (GRBs) are associated to the death of massive stars and have been discovered, so far, up to z = 6.29. Therefore, they hold the promise of probing star-formation and metal enrichment up to very high redshifts. However, the present GRB samples with redshift determinations are largely incomplete, and therefore a careful analysis of selection effects plaguing these samples is mandatory before any conclusion can be drawn from the observed GRB redshift distribution. Methods. To this purpose we study and compare three well-defined samples of long GRBs detected by Swift, HETE2, and BeppoSAX. Results. We find that Swift GRBs are, on average, slighly fainter and harder than BeppoSAX and HETE2 GRBs, as expected due to the higher energy range (15-150 keV) in which Swift GRBs are detected and localized, compared to BeppoSAX and HETE2 (≈2−20 keV). Gas and dust obscuration plays a role in shaping both the GRB samples and, most interestingly, the present samples of GRBs with redshift determination. In particular, we argue that the majority of the bright Swift GRBs without redshift might actually be z < ∼ 2 events and, therefore, that the present Swift GRB sample with redshift is biased against low-z GRBs. On the other hand, the detection of bright UV rest-frame afterglows from high-z GRBs, and even from those with large X-ray obscuration, implies a lower dust amount than in nearby GRBs and/or a different dust composition. If this is the case, the Swift sample of GRBs with redshifts is probably a fair sample of the real high-z GRB population. The absence of high-z GRBs in the BeppoSAX and HETE2 samples of GRBs with redshifts is probably due to how, at the time of BeppoSAX and HETE2 follow-up, faint afterglows of high-redshift GRBs will have weakened below the spectroscopic capabilities of even 10m-class telescopes. The redshift distribution of a subsample of Swift GRBs with distributions of peak fluxes, X-ray obscuration and optical magnitude at a fixed observing time similar to those of the BeppoSAX and HETE2 samples, is roughly consistent with the real BeppoSAX+HETE2 redshift distribution.

show abstract

Extinction properties of the X-ray bright/optically faint afterglow of GRB 020405

Cited by 41 publications

References 41 publications

Determining the Dust Extinction of Gamma-ray Burst Host Galaxies: A Direct Method Based on Optical and X-ray Photometry

Determining the Dust Extinction of Gamma-ray Burst Host Galaxies: A Direct Method Based on Optical and X-ray Photometry

Dust Extinction of Gamma-Ray Burst Host Galaxies: Identification of Two Classes?

Selection effects shaping the gamma ray burst redshift distributions

Contact Info

Product

Resources

About