Discovery of a Transient Absorption Edge in the X-ray Spectrum of GRB 990705

Amati, L.; Frontera, F.; Vietri, M.; Zand, J. J. M. in ’t; Soffitta, P.; Costa, E.; Sordo, S. Del; Pian, E.; Piro, L.; Antonelli, L. A.; Fiume, D. Dal; Feroci, M.; Gandolfi, G.; Guidorzi, C.; Heise, J.; Kuulkers, E.; Masetti, N.; Montanari, E.; Nicastro, L.; Orlandini, M.; Palazzi, E.

doi:10.1126/science.290.5493.953

Cited by 170 publications

(218 citation statements)

References 19 publications

Supporting

Mentioning

202

Contrasting

Order By: Relevance

“…INTRODUCTION The detection of spectral signatures associated with the environment of a g-ray burst (GRB) would provide important clues about the triggering mechanism and the progenitor (Mészáros & Rees 1998;Lazzati, Campana, & Ghisellini 1999;Böttcher 2000). Observations with Chandra, ASCA, and BeppoSAX have provided tentative evidence for Fe Ka line and edge features in at least five bursts; GRB 970508 (Piro et al 1999), GRB 970828 (Yoshida et al 1999), GRB 991216 (Piro et al 2000), and GRB 000214 (Antonelli et al 2000) all show an emission feature during the X-ray afterglow a few hours to a day after the burst event, while GRB 990705 (Amati et al 2000) displays a prominent X-ray absorption feature during the burst itself. Although most of the line detections are only marginally significant and fail to distinguish between the various line excitation mechanisms, 1 GRB 991216 shows a keV line at a mod-3.49 ‫ע‬ 0.06 erate confidence level (∼4 j).…”

mentioning

confidence: 99%

Iron Kα Emission from X-Ray Reflection: Predictions for Gamma-Ray Burst Models

Ballantyne¹,

Ramírez-Ruiz²

2001

The Astrophysical Journal

View full text Add to dashboard Cite

Recent observations of several g-ray burst (GRB) afterglows have shown evidence for a large amount of X-ray line-emitting material, possibly arising from ionized iron. A significant detection of an X-ray spectral feature, such as that found in the Chandra observation of GRB 991216, may provide important constraints on the immediate environment of the burst and hence on progenitor models. The large Fe Ka equivalent widths inferred from the X-ray observations favor models in which the line is produced when the primary X-ray emission from the source strikes Thomson-thick material and Compton scatters into our line of sight. We present such reflection spectra here, computed in a fully self-consistent manner, and discuss the range of ionization parameters that may be relevant to different models of GRBs. We argue that the presence of a strong hydrogen-like Ka line is unlikely, because Fe xxvi photons would be trapped resonantly and removed from the line core by Compton scattering. In contrast, a strong narrow emission line from He-like Fe xxv is prominent in the model spectra. We briefly discuss how these constraints may affect the line energy determination in GRB 991216.

show abstract

mentioning

confidence: 99%

Iron Kα Emission from X-Ray Reflection: Predictions for Gamma-Ray Burst Models

Ballantyne¹,

Ramírez-Ruiz²

2001

The Astrophysical Journal

View full text Add to dashboard Cite

show abstract

“…GRB 990705 had a 3.8 keV absorption edge in its prompt X-ray emission, consistent with the K-shell of iron at (Amati et al 2000). The other events showed z p 0.86 an emission feature in their after-glows, the iron equivalent of Lyman alpha or a combination feature: GRB 991216 at z p (Piro et al 2000a), GRB 000214 at (Antonelli 1.00 z p 0.…”

Section: Bursters and Supernovaementioning

confidence: 84%

Astrophysics in 2001

Trimble¹,

Aschwanden²

2002

PUBL ASTRON SOC PAC

View full text Add to dashboard Cite

ABSTRACT. During the year, astronomers provided explanations for solar topics ranging from the multiple personality disorder of neutrinos to cannibalism of CMEs (coronal mass ejections) and extrasolar topics including quivering stars, out-of-phase gaseous media, black holes of all sizes (too large, too small, and too medium), and the existence of the universe. Some of these explanations are probably probably true, though the authors are not betting large sums on any one. The data ought to remain true forever, though this requires a careful definition of "data" (think of the Martian canals).

show abstract

“…The particle density is 3 10 31 e ¤ cm 3 . If we assume that the magnetic energy B 2 2µ 0 4 10 28 erg cm 3 is shared among them, each particle gets an energy ε 0 1 § 3η acc 10 3 erg, where η acc is the acceleration efficiency.…”

Section: Energetics Time Duration and Variabilitymentioning

confidence: 99%

“…The temporal decay of the emission in different frequencies for several GRBs has been interpreted according to the fireball model and suggested jet beaming with opening angle θ 4 £ [2]. Another important discovery made in the last year is the presence of iron lines in the X-ray spectrum of GRBs (for example [3,4,5]). This provides a powerful tool to understand the nature and the environment of GRB primary sources [6,7].…”

Section: Phenomenological Overviewmentioning

confidence: 99%

The Blandford-Znajek mechanism with vacuum breakdown as a gamma-ray burst progenitor

Barbiellini¹,

Longo²

2001

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract.The energetics of the long duration GRB phenomenum is compared with the BZ mechanism. A rough estimate of the energy extracted from a rotating Black Hole with the Blandford-Znajek mechanism is evaluated with a very simple assumption: an inelastic collision between the rotating BH and an accreting torus. The GRB energetics requires an high magnetic field that breaks down the vacuum around the BH and gives origin to a e ¢ fireball. PHENOMENOLOGICAL OVERVIEWGamma-ray Bursts (GRBs) until a few years ago were largely devoid of any observable counterpart at any other wavelengths. However, a dramatic development in the last several years has been the measurement and localization of fading X-ray signals from some GRBs, lasting typically for days and making possible the optical and radio detection of afterglows, which mark the location of the GRB event. These afterglows in turn enabled the measurement of redshift distances, the identification of host galaxies, and the confirmation that GRB were at cosmological distances (for a recent brief review see [1]). The temporal decay of the emission in different frequencies for several GRBs has been interpreted according to the fireball model and suggested jet beaming with opening angle θ 4Another important discovery made in the last year is the presence of iron lines in the X-ray spectrum of GRBs (for example [3,4,5]). This provides a powerful tool to understand the nature and the environment of GRB primary sources [6,7]. The presence of strong iron lines implies a rich environment located very close to the GRB and it may be an argument in favour of massive-star progenitor models of GRB [8,9,10,11].The presence of an iron cloud is in favour of the interpretation of GRBs as a second step of the residual of the primary explosion(e.g. [11]). In this interpretation the primary explosion leaves over a compact object that could be a rotating black hole, at the center of the environment consisting of ejecta. In this scenario, it is plausible the hypothesis of energy extraction from a rotating BH (compact object left over from the primary explosion), through the Blandford-Znajek mechanism [12], where the external magnetic field can be supplied by an Fe torus circulating around the BH at a distance R (of the order of R s ).

show abstract

Discovery of a Transient Absorption Edge in the X-ray Spectrum of GRB 990705

Cited by 170 publications

References 19 publications

Iron Kα Emission from X-Ray Reflection: Predictions for Gamma-Ray Burst Models

Iron Kα Emission from X-Ray Reflection: Predictions for Gamma-Ray Burst Models

Astrophysics in 2001

The Blandford-Znajek mechanism with vacuum breakdown as a gamma-ray burst progenitor

Contact Info

Product

Resources

About