2017A&A...598A..23N


C.D.S. - SIMBAD4 rel 1.7 - 2020.07.05CEST09:05:33

2017A&A...598A..23N - Astronomy and Astrophysics, volume 598A, 23-23 (2017/2-1)

The 999th Swift gamma-ray burst: Some like it thermal A multiwavelength study of GRB 151027A.

NAPPO F., PESCALLI A., OGANESYAN G., GHIRLANDA G., GIROLETTI M., MELANDRI A., CAMPANA S., GHISELLINI G., SALAFIA O.S., D'AVANZO P., BERNARDINI M.G., COVINO S., CARRETTI E., CELOTTI A., D'ELIA V., NAVA L., PALAZZI E., POPPI S., PRANDONI I., RIGHINI S., ROSSI A., SALVATERRA R., TAGLIAFERRI G., TESTA V., VENTURI T. and VERGANI S.D.

Abstract (from CDS):

We present a multiwavelength study of GRB 151027A. This is the 999th gamma-ray burst detected by the Swift satellite and it has a densely sampled emission in the X-ray and optical band and has been observed and detected in the radio up to 140 days after the prompt. The multiwavelength light curve from 500s to 140 days can be modelled through a standard forward shock afterglow, but it requires an additional emission component to reproduce the early X-ray and optical emission. We present optical observations performed with the Telescopio Nazionale Galileo (TNG) and the Large Binocular Telescope (LBT) 19.6, 33.9, and 92.3 days after the trigger which show a bump with respect to a standard afterglow flux decay and are interpreted as possibly due to the underlying supernova and host galaxy (at a level of ∼0.4µJy in the optical R band, RAB∼25). Radio observations, performed with the Sardinia Radio Telescope (SRT) and Medicina in single-dish mode and with the European Very Long Baseline Interferometer (VLBI) Network and the Very Long Baseline Array (VLBA), between day 4 and 140 suggest that the burst exploded in an environment characterized by a density profile scaling with the distance from the source (wind profile). A remarkable feature of the prompt emission is the presence of a bright flare 100s after the trigger, lasting ∼70s in the soft X-ray band, which was simultaneously detected from the optical band up to the MeV energy range. By combining Swift-BAT/XRT and Fermi-GBM data, the broadband (0.3-1000 keV) time resolved spectral analysis of the flare reveals the coexistence of a non-thermal (power law) and thermal blackbody components. The blackbody component contributes up to 35% of the luminosity in the 0.3-1000keV band. The γ-ray emission observed in Swift-BAT and Fermi-GBM anticipates and lasts less than the soft X-ray emission as observed by Swift-XRT, arguing against a Comptonization origin. The blackbody component could either be produced by an outflow becoming transparent or by the collision of a fast shell with a slow, heavy, and optically thick fireball ejected during the quiescent time interval between the initial and later flares of the burst.

Abstract Copyright: © ESO, 2017

Journal keyword(s): gamma-ray burst: individual: GRB 151027A - radiation mechanisms: thermal - radiation mechanisms: non-thermal

Simbad objects: 9

goto Full paper

goto View the reference in ADS

Number of rows : 9

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 GRB 130925A gB 02 44 42.38 -26 09 15.8           ~ 114 0
2 GRB 970508 gB 06 53 49.2 +79 16 19           ~ 840 1
3 SN 2013cq SN* 11 32 32.84 +27 41 56.2           SNIc 378 1
4 8C 1745+624 QSO 17 46 14.03413721 +62 26 54.7383903   20.91 19.51     ~ 106 1
5 7C 180550.40+614045.00 QSO 18 06 19.9455349665 +61 41 18.337406381   18.9   18.8   ~ 10 1
6 GRB 151027A gB 18 09 56.86 +61 21 11.9           ~ 69 0
7 [VV96] J181536.8+612711 BLL 18 15 36.7901690411 +61 27 11.626463363   21.272   19.122   ~ 29 1
8 SN 1998bw SN* 19 35 03.17 -52 50 46.1   14.09       SNIc 1650 2
9 NGC 7027 PN 21 07 01.8 +42 14 10   9.1 10.9     ~ 2322 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2017A&A...598A..23N and select 'bookmark this link' or equivalent in the popup menu


2020.07.05-09:05:33

© Université de Strasbourg/CNRS

    • Contact