# Structured Jets and X-ray Plateaus in Gamma-Ray Burst Phenomena

## TL;DR

This paper demonstrates that high-latitude emission from structured jets can naturally produce X-ray plateaus in gamma-ray burst light curves, offering an alternative explanation to external shock models.

## Contribution

It introduces a model where structured jet high-latitude emission explains X-ray plateaus independently of external shock radiation.

## Key findings

- Structured jet high-latitude emission can produce X-ray plateaus.
- The model explains shallow decay phases in GRB X-ray light curves.
- Potential to account for chromatic optical/X-ray light curve features.

## Abstract

The first multi-messenger detection of a binary neutron star merger, GW170817, brought to the forefront the structured jet model as a way to explain multi-wavelength observations taken more than a year after the event. Here we show that the high-latitude emission from a structured jet can naturally produce an X-ray plateau in gamma-ray burst (GRB) light curves, independent of the radiation from an external shock. We calculate the radiation from a switched-off shell featuring an angular structure in both its relativistic bulk motion and intrinsic brightness. Our model is able to explain the shallow decay phase (plateau) often observed in GRB X-ray light curves. We discuss the possible contribution of the structured jet high-latitude emission to other distinctive features of GRB X-ray light curves, and its capability to explain the chromatic optical/X-ray light curve properties.