On-the-Fly Mapping of New Pulsars

TL;DR

This paper introduces a rapid on-the-fly mapping technique for localizing newly discovered pulsars with high precision, significantly reducing telescope time compared to traditional methods, and aiding in pulsar timing array research.

Contribution

The authors develop and demonstrate a practical, efficient method for quick pulsar localization using on-the-fly mapping, improving accuracy and resource use over existing strategies.

Findings

Achieved 1-3' localization accuracy with the GBT within minutes.

Reduced telescope time by a factor of 2-3 compared to traditional methods.

Identified positional discrepancies leading to improved pulsar timing solutions.

Abstract

Current single dish, low-frequency radio pulsar surveys provide efficient sky coverage, but poor localization of new discoveries. Here, we describe a practical technique for rapidly localizing pulsars discovered in these surveys with on-the-fly mapping and provide code to facilitate and formalize its implementation. As a proof of concept, we alter the positions of four test sources and use the Green Bank Telescope (GBT) 350 MHz receiver to recover source positions within $\approx$1$-$3' of their true values, compared to an 18' error radius for new discoveries. Achieving similar precision with a traditional gridding strategy using the GBT requires 2$-$3 times as much telescope time (including overhead), multiple receivers and relies on assumptions about the pulsars' spectral indices. For one of our test sources (PSR J1400$-$1431), this method revealed a discrepancy with the initial, published position, prompting additional follow-up and an improved timing solution. Rapid localization is important for improving data quality and providing flexibility in choice of center frequency for future timing observations - both of which facilitate evaluating new millisecond pulsars for potential inclusion in pulsar timing arrays.