CGRO/BATSE Data Support the New Paradigm for GRB Prompt Emission and the New L$_{i}^{nTh}$-E$_{peak,i}^{nTh,rest}$ relation

Abstract

The paradigm for GRB prompt emission is changing. Since early in the CGRO era, the empirical Band function has been considered a good description of the keV-MeV spectra although its shape is very often inconsistent with the predictions of the pure synchrotron emission scenarios. We have recently established a new observational model analyzing data of the NASA Fermi Gamma-ray Space Telescope. In this model, GRB prompt emission is a combination of three main emission components: (i) a thermal-like component that we interpreted so far as the jet photosphere emission, (ii) a non-thermal component that we interpreted so far as synchrotron radiation, and (iii) an additional non-thermal (cutoff) power-law most likely of inverse Compton origin. In this article we reanalyze some of the bright GRBs observed with CGRO/BATSE with the new model, namely GRBs 941017, 970111 and 990123. We conclude that BATSE data are fully consistent with the recent results obtained with Fermi: some bright BATSE GRBs exhibit three separate components during the prompt phase with similar spectral parameters as these reported from Fermi data. In addition, the analysis of the BATSE GRBs with the new model results in a relation between the time-resolved energy flux of the non-thermal component and its corresponding $ν$F$_ν$ peak energy (i.e., F$_{i}^{nTh}$-E$_{peak,i}^{nTh}$) that has a similar index as the one initially derived from Fermi data. For GRBs with known redshift (z) this results in a possible universal relation between the luminosity of the non-thermal component and its corresponding $ν$F$_ν$ peak energy in the rest frame (i.e., L$_{i}^{nTh}$-E$_{peak,i}^{NT,rest}$). We estimated z for GRBs 941017 and 970111 using GRB 990123--with z=1.61--as a reference. The estimated z for GRB 941017 is typical for long GRBs and the estimated z for GRB 970111 is right in the range of the expected values for this burst.