Discovery of 26 new Galactic radio transients by MeerTRAP

TL;DR

This paper reports the discovery of 26 new Galactic radio transients, mainly RRATs, using the MeerTRAP pipeline with MeerKAT, providing new insights into their properties and behaviors.

Contribution

The study introduces a real-time search pipeline for Galactic transients and reports the discovery and detailed analysis of 26 new radio transient sources, including their timing and localization.

Findings

26 new Galactic radio transients discovered

Timing solutions for five sources spanning multiple years

One source with a 17.5-second rotation period

Abstract

Radio searches for single pulses provide the opportunity to discover one-off events, fast transients and some pulsars that might otherwise be missed by conventional periodicity searches. The MeerTRAP real-time search pipeline operates commensally to observations with the MeerKAT telescope. Here, we report on 26 new Galactic radio transients, mostly rotating radio transients (RRATs) and also the detection of one RRAT and two pulsars that were independently discovered by other surveys. The dispersion measures of two of the new sources marginally exceed the Galactic contribution depending on the electron density model used. Using a simple method of fitting a Gaussian function to individual pulses, and obtaining positions of arcsecond accuracy from image-based localisations using channelised voltage data from our transient buffer, we have derived timing solutions spanning multiple years for five sources. The timing parameters imply ages of several Myr and low surface magnetic field strengths which is characteristic of RRATs. We were able to measure spin periods for eight more transients, including one source which appears to rotate every 17.5 seconds. A majority of the sources have only been seen in one observation, sometimes despite multiple return visits to the field. Some sources exhibit complex emission features like component switching and periodic microstructure.