Observations of Giant Pulses from Pulsar PSR B0950+08 using LWA1

TL;DR

This study reports the detection and analysis of 119 giant pulses from pulsar PSR B0950+08 at 39.4 MHz, revealing their properties, distribution, and frequency dependence, using the LWA1 telescope over 24 hours.

Contribution

First detection of giant pulses from PSR B0950+08 at 39 MHz, with detailed characterization of their distribution, widths, and frequency dependence, expanding understanding of pulsar emission at low frequencies.

Findings

119 giant pulses detected in 24 hours

Giant pulse rate is about 5 per hour

Pulse strength distribution follows a steep power law

Abstract

We report the detection of giant pulse emission from PSR B0950+08 in 24 hours of observations made at 39.4 MHz, with a bandwidth of 16 MHz, using the first station of the Long Wavelength Array, LWA1. We detected 119 giant pulses from PSR B0950+08 (at its dispersion measure), which we define as having SNRs at least 10 times larger than for the mean pulse in our data set. These 119 pulses are 0.035% of the total number of pulse periods in the 24 hours of observations. The rate of giant pulses is about 5.0 per hour. The cumulative distribution of pulse strength $S$ is a steep power law, $N(>S)\propto S^{-4.7}$, but much less steep than would be expected if we were observing the tail of a Gaussian distribution of normal pulses. We detected no other transient pulses in a dispersion measure range from 1 to 90 pc cm$^{-3}$, in the beam tracking PSR B0950+08. The giant pulses have a narrower temporal width than the mean pulse (17.8 ms, on average, vs. 30.5 ms). The pulse widths are consistent with a previously observed weak dependence on observing frequency, which may be indicative of a deviation from a Kolmogorov spectrum of electron density irregularities along the line of sight. The rate and strength of these giant pulses is less than has been observed at $\sim$100 MHz. Additionally, the mean (normal) pulse flux density we observed is less than at $\sim$100 MHz. These results suggest this pulsar is weaker and produces less frequent giant pulses at 39 MHz than at 100 MHz.