Spectral indices for radio emission of 228 pulsars

TL;DR

This study determines spectral indices for 228 pulsars using Parkes data, revealing their distribution and exploring links to pulsar emission mechanisms, with most spectra newly measured.

Contribution

It provides the largest set of pulsar spectral indices to date, including 200 new measurements, and investigates their relation to pulsar magnetospheric processes.

Findings

Spectral indices range from -4.84 to -0.46.

Weak correlations found between spectral index, $ ext{dot{E}}$, and $ ext{Delta}\Psi$.

Most spectra are newly determined, expanding existing pulsar data.

Abstract

We determine spectral indices of 228 pulsars by using Parkes pulsar data observed at 1.4 GHz, among which 200 spectra are newly determined. The indices are distributed in the range from -4.84 to -0.46.Together with known pulsar spectra from literature, we tried to find clues to the pulsar emission process. The weak correlations between the spectral index, the spin-down energy loss rate $\dot{E}$ and the potential drop in the polar gap $\Delta\Psi$ hint that emission properties are related to the particle acceleration process in a pulsar's magnetosphere.