MAGICal GRB 190114C: Implications of cutoff in the spectrum at sub-$GeV$ energies

Abstract

GRB 190114C is an unusual gamma-ray burst (GRB) due to its detection at sub-$TeV$ energies by MAGIC, seen at redshift z = 0.42. This burst is one of the brightest GRB detected by \fermi. A joint GBM-LAT analysis of the prompt emission reveals the presence of sub-$GeV$ spectral cutoff when the LAT \emph{low-energy events} (LLE) data is also examined. A similar high-energy cutoff was likewise reported in GRB 160509A and GRB 100724B earlier, as well as handful of other sources. The cutoff can be explained by the intrinsic opacity due to pair production within the emitting region. GRB 190114C shows a transition from non-thermal to a quasi-thermal-like spectrum and a radiation component that can be attributed to afterglow. Based on spectral analysis, we constrain the site of the prompt emission and $Lorentz$ factor. Knowing that sub-$TeV$ photons are detected in MAGIC, we perceive that the observed spectrum is indeed an overlap from two emission sites, where the emission observed in \fermi is more consistent with prompt emission produced via photospheric dissipation along with a concurrent component from the external shock.

arXiv commentRevised and accepted for publication in the ApJ

References in corpus (40)

• The Physics of Gamma-Ray Bursts and Relativistic Jets
• Lower Limits on Lorentz Factors in Gamma Ray Bursts
• The First Fermi LAT Gamma-Ray Burst Catalog
• Detection of a Thermal Spectral Component in the Prompt Emission of GRB 100724B
• Observation of inverse Compton emission from a long $\gamma$-ray burst
• Is Thermal Emission in Gamma-Ray Bursts Ubiquitous?
• GRB110721A: An extreme peak energy and signatures of the photosphere
• Evidence of an initially magnetically dominated outflow in GRB 080916C
• A new method of determining the initial size and Lorentz factor of gamma-ray burst fireballs using a thermal emission component
• Evidence for a Photospheric Component in the Prompt Emission of the Short GRB120323A and its Effects on the GRB Hardness-Luminosity Relation
• Gamma-ray bursts as cool synchrotron sources
• Synchrotron Origin of the Typical GRB Band Function - A Case Study of GRB 130606B
• On The External Shock Synchrotron Model for GRBs' GeV Emission
• A Turbulent Model of Gamma-Ray Burst Variability
• Towards a Better Understanding of the GRB Phenomenon: a New Model for GRB Prompt Emission and its effects on the New Non-Thermal L${}_{\mathrm{i}}^{\mathrm{NT}}$-E${}_{\mathrm{peak},\mathrm{i}}^{\mathrm{rest},\mathrm{NT}}$ relation
• Detection of Low-energy Breaks in Gamma-Ray Burst Prompt Emission Spectra
• Evidence of two spectral breaks in the prompt emission of gamma ray bursts
• Prompt optical emission as a signature of synchrotron radiation in gamma-ray bursts
• The Bright and the Slow -- GRBs 100724B \& 160509A with high-energy cutoffs at $\lesssim 100$MeV
• Radiative Transfer Models for Gamma-Ray Bursts
• New Fermi-LAT event reconstruction reveals more high-energy gamma rays from Gamma-ray bursts
• Variable jet properties in GRB110721A: Time resolved observations of the jet photosphere
• Characterization of Gamma-Ray Burst prompt emission spectra down to soft X-rays
• Analysis and modelling of the multi-wavelength observations of the luminous GRB 190114C
• Fermi observations of high-energy gamma-ray emission from GRB 080825C
• MultiPulse {\it Fermi} Gamma-Ray Bursts. I. Evidence of the Transition from Fireball to Poynting-flux-dominated Outflow
• GRB 131014A: a Laboratory to Study the Thermal-Like and Non-Thermal Emissions in Gamma-Ray Bursts, and the new L${}_{\mathrm{i}}^{\mathrm{nTh}}$-E${}_{\mathrm{peak},\mathrm{i}}^{\mathrm{nTh},\mathrm{rest}}$ relation
• Photospheric Emission of Gamma-Ray Bursts
• GRB 190114C: from prompt to afterglow?
• Thermal Components in Gamma-ray Bursts. I. How Do They Affect Non-Thermal Spectral Parameters?
• Diagnosing GRB Prompt Emission Site with Spectral Cut-Off Energy
• The Fraction of Gamma-ray Bursts with an Observed Photospheric Emission Episode
• A Unified Model for GRB Prompt Emission from Optical to $\gamma$-Rays: Exploring GRBs as Standard Candles
• Is Spectral Width a Reliable Measure of GRB Emission Physics?
• Evaluating the bulk Lorentz factors of outflow material: lessons learned from the extremely-energetic outburst GRB 160625B
• The Effect of Pair Cascades on the High-Energy Spectral Cutoff in Gamma-Ray Bursts
• Investigating subphotospheric dissipation in gamma-ray bursts using joint Fermi-Swift observations
• Discovery of Smoothly Evolving Blackbodies in the Early Afterglow of GRB 090618 : Evidence for a Spine-Sheath Jet?
• A new method of pulse-wise spectral analysis of Gamma-ray Bursts
• GRB 190114C: An Upgraded Legend

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• Insights into the physics of GRBs from the high-energy extension of their prompt emission spectra
• Bethe-Heitler signature in proton synchrotron models for gamma-ray bursts
• A Comprehensive Study of Bright Fermi-GBM Short Gamma-Ray Bursts: I. Multi-Pulse Lightcurves and Multi-Component Spectra
• Searching for an additional high-energy component in Fermi-LAT GRB afterglows
• Extreme Transients in Gamma Rays