The nature of the late achromatic bump in GRB 120326A

Melandri, A.; Virgili, F. J.; Guidorzi, C.; Bernardini, M. G.; Kobayashi, S.; Mundell, C. G.; Gomboc, A.; Dintinjana, B.; Hentunen, V. P.; Japelj, J.; Kopač, D.; Kuroda, D.; Morgan, A. N.; Steele, I. A.; Quadri, U.; Arici, G.; Arnold, D. M.; Girelli, R.; Hanayama, H.; Kawai, N.; Mikuz, H.; Nissinen, M.; Salmi, T.; Smith, R. J.; Strabla, L.; Tonincelli, M.; Quadri, A.

doi:10.1051/0004-6361/201424338

Cited by 24 publications

(24 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This diagnostic tool has been successfully applied to GRBs displaying early-and/or late-time strong variability (e.g. Margutti et al 2010;De Cia et al 2011;Melandri et al 2014b). In Fig.…”

Section: Late Time Flare Emission/refreshed Shockmentioning

confidence: 99%

The high-redshift gamma-ray burst GRB 140515A

Melandri

Bernardini

D’Avanzo

et al. 2015

A&A

Self Cite

View full text Add to dashboard Cite

High-redshift gamma-ray bursts (GRBs) offer several advantages when studying the distant Universe, providing unique information about the structure and properties of the galaxies in which they exploded. Spectroscopic identification with large ground-based telescopes has improved our knowledge of this kind of distant events. We present the multi-wavelength analysis of the high-z Swift GRB GRB 140515A (z = 6.327). The best estimate of the neutral hydrogen fraction of the intergalactic medium towards the burst is x HI ≤ 0.002. The spectral absorption lines detected for this event are the weakest lines ever observed in GRB afterglows, suggesting that GRB 140515A exploded in a very low-density environment. Its circum-burst medium is characterised by an average extinction (A V ∼ 0.1) that seems to be typical of z ≥ 6 events. The observed multi-band light curves are explained either with a very hard injected spectrum (p = 1.7) or with a multi-component emission (p = 2.1). In the second case a long-lasting central engine activity is needed in order to explain the late time X-ray emission. The possible origin of GRB 140515A in a Pop III (or in a Pop II star with a local environment enriched by Pop III) massive star is unlikely.

show abstract

“…This diagnostic tool has been successfully applied to GRBs displaying early-and/or late-time strong variability (e.g. Margutti et al 2010;De Cia et al 2011;Melandri et al 2014b). In Fig.…”

Section: Late Time Flare Emission/refreshed Shockmentioning

confidence: 99%

The high-redshift gamma-ray burst GRB 140515A

Melandri

Bernardini

D’Avanzo

et al. 2015

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…The plateau phase cannot be explained in the framework of the simple standard external shock scenario (i.e., synchrotron radiation produced by the interaction of a relativistic ejecta with the circum-burst medium; see Piran et al 1993;Mészáros & Rees 1997; for reviews). On the other hand, some optical afterglows show rebrightenings at late stages ( -10 10 4 5 s), together with a bump occasionally occurring in the X-ray band (e.g., GRB 120326A, Melandri et al 2014;Hou et al 2014;Laskar et al 2015), or without clear counterpart features in X-rays (e.g., GRB 100814A, De Pasquale et al 2015;GRB 081029, Nardini et al 2011;GRB 100621A, Greiner et al 2013). These rebrightenings also deviate from the expectations of the external shock model, which calls for a refined afterglow model.…”

Section: Introductionmentioning

confidence: 99%

Imprints of Electron–positron Winds on the Multiwavelength Afterglows of Gamma-Ray Bursts

Geng

Huang

et al. 2016

ApJ

View full text Add to dashboard Cite

Optical rebrightenings in the afterglows of some gamma-ray bursts (GRBs) are unexpected within the framework of the simple external shock model. While it has been suggested that the central engines of some GRBs are newly born magnetars, we aim to relate the behaviors of magnetars to the optical rebrightenings. A newly born magnetar will lose its rotational energy in the form of Poynting-flux, which may be converted into a wind of electron-positron pairs through some magnetic dissipation processes. As proposed by Dai, this wind will catch up with the GRB outflow and a long-lasting reverse shock (RS) would form. By applying this scenario to GRB afterglows, we find that the RS propagating back into the electron-positron wind can lead to an observable optical rebrightening and a simultaneous X-ray plateau (or X-ray shallow decay). In our study, we select four GRBs (i.e., GRB 080413B, GRB 090426, GRB 091029, and GRB 100814A), of which the optical afterglows are well observed and show clear rebrightenings. We find that they can be well interpreted. In our scenario, the spin-down timescale of the magnetar should be slightly smaller than the peak time of the rebrightening, which can provide a clue to the characteristics of the magnetar.

show abstract

“…These raw images were combined into 13 coadded frames for photometry. We note that the lightcurve presented by Melandri et al () shows a different behavior: the lightcurve decays from the very early times and there is no early rise and peak.…”

Section: Observationsmentioning

confidence: 51%

“…There is a number of studies for this gamma‐ray burst: Urata et al () deal with high energy emission, Melandri et al () and Hou et al () study the optical afterglow behavior.…”

Section: Observationsmentioning

confidence: 99%

Applying weighted image coaddition to observations of GRB optical afterglows at the D50 telescope in Ondřejov

et al. 2019

View full text Add to dashboard Cite

One of the primary observational objectives of the 0.5 m robotic telescope of Ondřejov observatory is the ground-based follow-up of gamma-ray burst triggers.This independent robotic observatory has been in operation since 2008 and has followed up more than a hundred events localized by the Swift or INTEGRAL satellites. We describe the use of the weighted coaddition of astronomical images while applying this method to observations of GRB optical afterglows. We present optical photometric observations of the detected optical afterglows. The collection contains several faint optical afterglows, in some cases a lightcurve is available, in some cases only a single point detection has been achieved. A brief collection of available information is presented for each of the events together with our fitting and analysis.

show abstract

The nature of the late achromatic bump in GRB 120326A

Cited by 24 publications

References 61 publications

The high-redshift gamma-ray burst GRB 140515A

The high-redshift gamma-ray burst GRB 140515A

Imprints of Electron–positron Winds on the Multiwavelength Afterglows of Gamma-Ray Bursts

Applying weighted image coaddition to observations of GRB optical afterglows at the D50 telescope in Ondřejov

Contact Info

Product

Resources

About