Arecibo Pulsar Survey Using ALFA: Probing Radio Pulsar Intermittency and Transients

TL;DR

This paper details the PALFA survey's algorithms and discoveries of radio transients, including the smallest known duty cycle pulsar, and discusses how observational effects influence pulsar detection and classification.

Contribution

It introduces new search algorithms, reports seven new pulsar discoveries, and analyzes the effects of observational biases on pulsar intermittency detection.

Findings

Discovered seven new pulsars with one having a 0.01% duty cycle.

Compared efficiencies of periodicity and single pulse searches.

Derived constraints on transient pulse rates and flux densities.

Abstract

We present radio transient search algorithms, results, and statistics from the ongoing Arecibo Pulsar ALFA (PALFA) Survey of the Galactic plane. We have discovered seven objects by detecting isolated dispersed pulses and one of the new discoveries has a duty cycle of 0.01%, the smallest known. The impact of selection effects on the detectability and classification of intermittent sources is discussed, and the relative efficiencies of periodicity vs. single pulse searches are compared for various pulsar classes. We find that scintillation, off-axis detection and few rotation periods within an observation may misrepresent normal periodic pulsars as intermittent sources. Finally, we derive constraints on transient pulse rate and flux density from the PALFA survey parameters and results.