Speaker
Description
The $E_{\rm p,i}$--$L_{\rm iso}$ correlation of long gamma-ray bursts (LGRBs) has been regarded for a long time as a fundamental correlation for standardizing LGRBs to probe the cosmology and constrain LGRB physics. However, the authenticity of this correlation may be affected by potential selection effects, which are likely overlooked in the current small sample of LGRBs with measured redshift and luminosity. In this conference, I would like to present our recent work of simulating a large LGRB sample that can well reproduce the observed distributions of LGRB parameters to study the selection effects in the $E_{\rm p,i}$--$L_{\rm iso}$ correlation. We first obtain the mock $z$ and $L_{\rm iso}$ from the model of redshift and luminosity distributions in previous work, then yield the spectral parameters: $E_{\rm p,o}$ based on the observed bivariate ($E_{\rm p,i}\{z, E_{\rm p,o}\}$, $L_{\rm iso}$) distribution and $\alpha$ based on the observed bivariate ($\alpha$, $E_{\rm p,o}$) distribution. This allows the mock data for each parameter to perfectly follow the observed distribution. Based on this simulated sample, we find the ($E_{\rm p,i}$, $L_{\rm iso}$) distribution, which will directly affect the best-fitting result of the correlation, is significantly dependent on the value of peak flux $P$. This indicates that the effect of $P$ selection should be sufficiently considered in the study and use of the correlation. Notably, to make the simulated $P$ distribution consistent with the observed distribution, the mock $E_{\rm p,o}$ has to be obtained from the mock $E_{\rm p,i}$ which is simulated based on the observed ($E_{\rm p,i}$, $L_{\rm iso}$) distribution. This means that the ($E_{\rm p,i}$, $L_{\rm iso}$) distribution is still effective to constrain the LGRB parameters.
