| Name: | PRAGYAN PRATIM BORDOLOI |
| Affiliation: | INDIAN INSTITUTE OF SCIENCE EDUCATION AND RESEARCH THIRUVANANTHAPURAM |
| Conference ID : | ASI2024_561 |
| Title : | Identification and modelling of optically thin inverse Compton scattering in the prompt emission of GRB131014A |
| Authors : | Pragyan Pratim Bordoloi1, Shabnam Iyyani2 |
| Authors Affiliation: | 1 ) Indian Institute of Science Education and Research Thiruvananthapuram, Kerala, 695551, India
2) Indian Institute of Science Education and Research Thiruvananthapuram, Kerala, 695551, India |
| Mode of Presentation: | Poster |
| Abstract Category : | High Energy Phenomena, Fundamental Physics and Astronomy |
| Abstract : | The mechanism responsible for the prompt gamma-ray emission of a gamma-ray burst continues
to remain an enigma. The detailed analysis of the spectrum of GRB 131014A observed by the Fermi
gamma ray burst monitor and Large Area Telescope has revealed an unconventional spectral shape
that significantly deviates from the typical Band function. The spectrum exhibits three distinctive
breaks and an extended power law at higher energies. Furthermore, the lower end of the spectrum
aligns with power-law indices greater than -0.6, and in the brightest region of the burst, these
values approach +1. The lowest spectral break is thereby found to be consistent with a blackbody.
These observed spectral characteristics strongly suggest the radiation process to be inverse Compton scattering in an optically thin region. Applying the empirical fit parameters for physical modeling,we find that the kinetic energy of the GRB jet of bulk Lorentz factor, Γ = 395, gets dissipated just above the photosphere, approximately at a radius of 8 × 10^13 cm. The electrons involved in this
process are accelerated with a power-law index of δ = −1.5, and the minimum electron Lorentz
factor, γmin, is approximately 3.25. In summary, this study provides a comprehensive identification
and detailed modeling of optically thin inverse Compton scattering in the prompt emission of GRB
131014A. |
