The Northern High Time Resolution Universe pulsar survey: II. Single-pulse search set-up and simulations

TL;DR

This paper introduces a new single-pulse search pipeline for the HTRU survey, including software tools for injecting synthetic signals and handling RFI, validated with real data to detect known and new pulsar signals.

Contribution

The paper presents a novel single-pulse search pipeline with new software tools, enhancing detection capabilities and RFI mitigation for the HTRU survey data.

Findings

Pipeline successfully detects known pulsars and RRATs.

Discovered 8 faint SP trains potentially from new neutron stars.

Identified 141 isolated SP candidates for further study.

Abstract

The High Time Resolution Universe (HTRU) survey is an all-sky survey looking for pulsars and other radio transients. A new single-pulse (SP) search pipeline is presented, tailored to the northern part of the HTRU survey collected with the 100m Effelsberg Radio Telescope. In a selection of this data, synthetic SPs are injected with frequency-time structures resembling those of the detected Fast Radio Burst (FRB) population and processed by the pipeline to characterize its performance. Therefore, several new software toolkits have been developed (FRBfaker and RFIbye) to enable the injection of SPs with complex frequency-time structures and cope with the Radio Frequency Interference (RFI) in the survey's data. The operation of these toolkits is described alongside the overall functionality of the SP pipeline. Qualification of the pipeline confirmed that it is ready to process all the HTRU-North data. Additionally, the survey's sensitivity to SPs, the impact of RFI thereon, the performance of the deep-learning classifier FETCH, and some insights that may be used to improve the pipeline's performance in the future are determined. Within the small data sample analysed, 21 known pulsars and a RRAT are detected. In addition, eight faint SP trains that might originate from yet undiscovered neutron stars and 141 isolated SP candidates were discovered.