Observed Steep and Shallow Spectra, Narrow and Broadband Spectra, Multi-frequency Simultaneous Spectra, and Statistical Fringe Spectra in Fast Radio Bursts: Various Faces of Intrinsic Quasi-periodic Spectra?

TL;DR

This paper proposes that the diverse spectral features observed in fast radio bursts can be explained by intrinsically quasi-periodic spectra generated by coherent curvature radiation from structured bunches, offering insights into their formation mechanisms.

Contribution

It introduces a model linking various observed spectral phenomena in FRBs to intrinsic quasi-periodic spectra from structured bunches, advancing understanding of FRB emission mechanisms.

Findings

Spectral diversity in FRBs can be explained by intrinsic quasi-periodic spectra.

Multi-frequency simultaneous spectra provide clues about bunch structure periods.

Statistical fringe spectra may reveal properties of the emission region.

Abstract

In this paper, through analysis, modelings, and simulations, we show that if the spectra of fast radio bursts (FRBs) are intrinsically quasi-periodic spectra, likely produced by coherent curvature radiation from quasi-periodic structured bunches, then the observed steep and shallow spectra, narrow and broadband spectra, multi-frequency simultaneous spectra, as well as possible statistical fringe spectra in FRBs, could all be various manifestations of these intrinsically quasi-periodic spectra. If so, the period properties of the structured bunches, as inferred from the observed multi-frequency simultaneous spectra and potential statistical fringe spectra, may provide valuable insights into the mechanisms behind the formation of such structured bunches.