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Well-sampled optical light curves of 50 gamma-ray bursts (GRBs) with plateau features are compiled from the literature. By empirical fitting, we obtained the parameters of the optical plateaus, such as the decay slopes ($alpha_{rm 1}$ and $alpha_{rm 2}$), the break times ($T_{rm b}$), and the corresponding optical fluxes ($F_{rm b}$) at the break times. The break time of optical plateaus ranges from tens of seconds to $10^6$ seconds, with a typical value about $10^4$ seconds. We have calculated the break luminosity, and it mainly ranges from $10^{44}$ erg $s^{-1}$ to $10^{47}$ erg $s^{-1}$, which is generally two or three orders of magnitude less than the corresponding break luminosity of the X-ray afterglow plateaus. We reanalyzed the optical plateaus and also found that a significantly tighter correlation exists when we added the isotropic equivalent energy of GRBs $E_{rm gamma,iso}$ into the $L_{rm b,z}-T_{rm b,z}$ relation. The best fit correlation is obtained to be $L_{rm b,z}propto T_{rm b,z}^{-0.9}E_{rm gamma,iso}^{0.4}$. We next explored the possible correlations among $L_{rm b,z}$, $T_{rm b,z}$ and $E_{rm p,i}$, and found there is also a tight correlation between them, which takes the form of $L_{rm b,z}propto T_{rm b,z}^{-0.9}E_{rm p,i}^{0.5}$. We argue that these two tight $L_{rm b,z}-T_{rm b,z}-E_{rm gamma,iso}$ and $L_{rm b,z}-T_{rm b,z}-E_{rm p,i}$ correlations are more physical, and it may be directly related to radiation physics of GRBs. The tight correlations are possible to be used as standard candles.
The optical light-curves of GRB afterglows display either peaks or plateaus. We identify 16 afterglows of the former type, 17 of the latter, and 4 with broad peaks, that could be of either type. The optical energy release of these two classes is si
Afterglows of gamma-ray bursts often show flares, plateaus, and sudden intensity drops: these temporal features are difficult to explain as coming from the forward shock. We calculate radiative properties of early GRB afterglows with the dominant con
I investigate the origin of the observed correlation between a GRBs nuFnu spectral peak Epk and its isotropic equivalent energy Eiso through the use of a population synthesis code to model the prompt gamma-ray emission from GRBs. By using prescriptio
We collect and reanalyze about 200 GRB data of prompt-emission with known redshift observed until the end of 2009, and select 101 GRBs which were well observed to have good spectral parameters to determine the spectral peak energy ($E_p$), 1-second p
It is now more than 40 years since the discovery of gamma-ray bursts (GRBs) and in the last two decades there has been major progress in the observations of bursts, the afterglows and their host galaxies. This recent progress has been fueled by the a