Skip to Main content Skip to Navigation
New interface
Journal articles

Colour variations in the GRB 120327A afterglow

Abstract : Aims. We present a comprehensive temporal and spectral analysis of the long Swift GRB 120327A afterglow data to investigate possible causes of the observed early-time colour variations.Methods. We collected data from various instruments and telescopes in X-ray, ultraviolet, optical, and near-infrared bands, and determined the shapes of the afterglow early-time light curves. We studied the overall temporal behaviour and the spectral energy distributions from early to late times.Results. The ultraviolet, optical, and near-infrared light curves can be modelled with a single power-law component between 200 and 2 × 104 s after the burst event. The X-ray light curve shows a canonical steep-shallow-steep behaviour that is typical of long gamma-ray bursts. At early times a colour variation is observed in the ultraviolet/optical bands, while at very late times a hint of a re-brightening is visible. The observed early-time colour change can be explained as a variation in the intrinsic optical spectral index, rather than an evolution of the optical extinction.Key words: gamma-ray burst: individual: GRB 120327A / dust, extinction⋆ Table 2 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/607/A29⋆⋆ Deceased.
Document type :
Journal articles
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-01645283
Contributor : INSPIRE HEP Connect in order to contact the contributor
Submitted on : Friday, August 5, 2022 - 8:33:06 AM
Last modification on : Tuesday, November 29, 2022 - 5:14:21 AM
Long-term archiving on: : Sunday, November 6, 2022 - 6:04:48 PM

File

aa31759-17.pdf
Publisher files allowed on an open archive

Identifiers

Citation

A. Melandri, S. Covino, E. Zaninoni, S. Campana, J. Bolmer, et al.. Colour variations in the GRB 120327A afterglow. Astron.Astrophys., 2017, 607, pp.A29. ⟨10.1051/0004-6361/201731759⟩. ⟨hal-01645283⟩

Share

Metrics

Record views

108

Files downloads

1