Statistical studies of optically dark gamma-ray bursts in the<i>Swift</i>era

Zheng, W.; Deng, J. S.; Wang, Jing

doi:10.1088/1674-4527/9/10/003

Cited by 24 publications

(36 citation statements)

References 78 publications

(114 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The neutral hydrogen column density 1.1 × 10 22 cm −2 measured in the time-averaged X-ray spectrum at z ∼ 4.7 is higher than the average value 7.9 × 10 21 cm −2 given by the statistics of Campana et al (2010). Zheng et al (2009) andCampana et al (2010) have suggested that the GRB X-ray absorption is intrinsic in general. GRB 100219A shows a "dark" property according to the criterion β OX ≤ 0.5 introduced by Jakobsson et al (2004a).…”

Section: Discussionmentioning

confidence: 69%

Diversity of multiwavelength emission bumps in the GRB 100219A afterglow

Mao

Malesani

D’Avanzo

et al. 2012

A&A

View full text Add to dashboard Cite

Context. Multi-wavelength observations of gamma-ray burst (GRB) afterglows provide important information about the activity of their central engines and their environments. In particular, the short timescale variability, such as bumps and/or rebrightening features visible in the multi-wavelength light curves, is still poorly understood. Aims. We analyze the multi-wavelength observations of the GRB 100219A afterglow at redshift 4.7. In particular, we attempt to identify the physical origin of the late achromatic flares/bumps detected in the X-ray and optical bands. Methods. We present ground-based optical photometric data and Swift X-ray observations on GRB 100219A. We analyzed the temporal behavior of the X-ray and optical light curves, as well as the X-ray spectra.Results. The early flares in the X-ray and optical light curves peak simultaneously at about 1000 s after the burst trigger, while late achromatic bumps in the X-ray and optical bands appear at about 2 × 10 4 s after the burst trigger. These are uncommon features in the afterglow phenomenology. Considering the temporal and spectral properties, we argue that both optical and X-ray emissions come from the same mechanism. The late flares/bumps may be produced by late internal shocks from long-lasting activity of the central engine. An off-axis origin for a structured jet model is also discussed to interpret the bump shapes. The early optical bump can be interpreted as the afterglow onset, while the early X-ray flare could be caused by the internal activity. GRB 100219A exploded in a dense environment as revealed by the strong attenuation of X-ray emission and the optical-to-X-ray spectral energy distribution.

show abstract

Section: Discussionmentioning

confidence: 69%

Diversity of multiwavelength emission bumps in the GRB 100219A afterglow

Mao

Malesani

D’Avanzo

et al. 2012

A&A

View full text Add to dashboard Cite

show abstract

“…the early reports about the faintness of the afterglows of Swift GRBs (Berger et al , 2005bZheng et al 2009a). …”

Section: Observed Light Curves Of Swift-era Grb Afterglowsmentioning

confidence: 97%

THE AFTERGLOWS OFSWIFT-ERA GAMMA-RAY BURSTS. I. COMPARING PRE-SWIFTANDSWIFT-ERA LONG/SOFT (TYPE II) GRB OPTICAL AFTERGLOWS

Канн

Klose

Zhang

et al. 2010

ApJ

287

356

View full text Add to dashboard Cite

15131514 KANN ET AL.Vol. 720 ABSTRACT We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing us to estimate the host-galaxy extinction. We transformed the afterglow light curves into an extinction-corrected z = 1 system and compared their luminosities with a sample of pre-Swift afterglows. The results of a former study, which showed that GRB afterglows clustered and exhibited a bimodal distribution in luminosity space, are weakened by the larger sample. We found that the luminosity distribution of the two afterglow samples (Swift-era and pre-Swift) is very similar, and that a subsample for which we were not able to estimate the extinction, which is fainter than the main sample, can be explained by assuming a moderate amount of line-of-sight host extinction. We derived bolometric isotropic energies for all GRBs in our sample, and found only a tentative correlation between the prompt energy release and the optical afterglow luminosity at 1 day after the GRB in the z = 1 system. A comparative study of the optical luminosities of GRB afterglows with echelle spectra (which show a high number of foreground absorbing systems) and those without, reveals no indication that the former are statistically significantly more luminous. Furthermore, we propose the existence of an upper ceiling on afterglow luminosities and study the luminosity distribution at early times, which was not accessible before the advent of the Swift satellite. Most GRBs feature afterglows that are dominated by the forward shock from early times on. Finally, we present the first indications of a class of long GRBs, which form a bridge between the typical highluminosity, high-redshift events and nearby low-luminosity events (which are also associated with spectroscopic supernovae) in terms of energetics and observed redshift distribution, indicating a continuous distribution overall.

show abstract

“…The value of β could be constrained from the Swift /XRT observations. To estimate β, we use the sample recently compiled by Zheng et al (2009). Zheng et al (2009) collected the information of amount of GRBs observed by Swift satellite before 2008 from the literature and on-line databases.…”

Section: Conclusion and Implicationmentioning

confidence: 99%

“…To estimate β, we use the sample recently compiled by Zheng et al (2009). Zheng et al (2009) collected the information of amount of GRBs observed by Swift satellite before 2008 from the literature and on-line databases. The number-flux relation of these GRBs is displayed in Figure 5 for the 3 keV X-ray flux density at 11 hour.…”

Section: Conclusion and Implicationmentioning

confidence: 99%

Not enough evidence to support the correlation between gamma-ray bursts and foreground galaxy clusters in theSwiftEra

Wang

Wei

2010

Res. Astron. Astrophys.

Self Cite

View full text Add to dashboard Cite

The correlation between distant Gamma-Ray Bursts (GRBs) and foreground galaxy clusters is re-examined by using the well localized (with an accuracy down to a few arcseconds) Swift/XRT GRBs. The galaxy clusters are compiled from both X-ray selected ROSAT brightest cluster sample (BCS) and BCS extension by requiring δ ≥ 0• and b ≥ 20• . The Swift/XRT GRBs fulfilling the above selection criteria are crosscorrelated with the clusters. Both Nearest-Neighbor Analysis and angular two-point crosscorrelation function show that there is no enough evidence supporting the correlation between the GRBs and foreground clusters. We suggest that the non-correlation is probably related to the GRB number-flux relation slope.

show abstract

Statistical studies of optically dark gamma-ray bursts in theSwiftera

Cited by 24 publications

References 78 publications

Diversity of multiwavelength emission bumps in the GRB 100219A afterglow

Diversity of multiwavelength emission bumps in the GRB 100219A afterglow

THE AFTERGLOWS OFSWIFT-ERA GAMMA-RAY BURSTS. I. COMPARING PRE-SWIFTANDSWIFT-ERA LONG/SOFT (TYPE II) GRB OPTICAL AFTERGLOWS

Not enough evidence to support the correlation between gamma-ray bursts and foreground galaxy clusters in theSwiftEra

Contact Info

Product

Resources

About