Detection of GRB 090618 with RT-2 Experiment Onboard the Coronas-Photon Satellite

TL;DR

This paper analyzes the gamma-ray emission of GRB 090618 using data from the RT-2 Experiment and Swift BAT, revealing detailed temporal and spectral evolution, including a systematic decrease in peak energy over successive pulses.

Contribution

It provides the first detailed temporal and spectral analysis of GRB 090618 combining RT-2 and Swift BAT data, highlighting pulse evolution.

Findings

Multiple peaks observed in GRB 090618

Spectral peak energy decreases monotonically over pulses

Combined data yields accurate spectral parameters

Abstract

We present the results of an analysis of the prompt gamma-ray emission from GRB 090618 using the RT-2 Experiment onboard the Coronas-Photon satellite. GRB 090618 shows multiple peaks and a detailed study of the temporal structure as a function of energy is carried out. As the GRB was incident at an angle of 77 degree to the detector axis, we have generated appropriate response functions of the detectors to derive the spectrum of this GRB. We have augmented these results using the publicly available data from the Swift BAT detector and show that a combined spectral analysis can measure the spectral parameters quite accurately. We also attempt a spectral and timing analysis of individual peaks and find evidence for a systematic change in the pulse emission characteristics for the successive pulses. In particular, we find that the peak energy of the spectrum, E_p, is found to monotonically decrease with time, for the successive pulses of this GRB.