The Optical Luminosity-Time Correlation for More than 100 Gamma-Ray Burst Afterglows

DOI: 
10.3847/2041-8213/abcda9
Publication date: 
01/12/2020
Main author: 
Dainotti, M. G.
IAA authors: 
Kann, D. A.
Authors: 
Dainotti, M. G.; Livermore, S.; Kann, D. A.; Li, L.; Oates, S.; Yi, S.; Zhang, B.; Gendre, B.; Cenko, B.; Fraija, N.
Journal: 
The Astrophysical Journal Letters
Refereed: 
Yes
Publication type: 
Article
Volume: 
905
Pages: 
L26
Issue: 
2
Abstract: 
Gamma-ray bursts (GRBs) are fascinating events due to their panchromatic nature. Their afterglow emission is observed from sub-TeV energies to radio wavelengths. We investigate GRBs that present an optical plateau, leveraging on the resemblance with the X-ray plateau shown in many GRB light curves (LCs). We comprehensively analyze all published GRBs with known redshifts and optical plateau observed mostly by the Neil Gehrels Swift Observatory (Swift). We fit 267 optical LCs and show the existence of the plateau in 102 cases, which is the largest compilation so far of optical plateaus. For 56 Swift GRBs with optical and X-ray plateaus, we compare the rest-frame end time at both wavelengths ( T∗opt , T∗X ), and conclude that the plateau is achromatic between T∗opt and T∗X . We also confirm the existence of the two-dimensional relations between T∗opt and the optical luminosity at the end of the plateau emission, which resembles the same luminosity-time correlation in X-rays (Dainotti et al. 2013). The existence of this optical correlation has been demonstrated for the largest sample of optical plateaus in the literature to date. The squared scatter in this optical correlation is smallest for the subset of the Gold GRBs with a decrease in the scatter equivalent to 52.4% when compared to the scatter of the entire GRB sample.
Database: 
ADS
ADS Bibcode: 
2020ApJ...905L..26D
Keywords: 
Gamma-ray bursts