The second set of pulsar discoveries by CHIME/FRB/Pulsar: 14 rotating radio transients and 7 pulsars

Abstract

ABSTRACT The Canadian Hydrogen Mapping Experiment (CHIME) is a radio telescope located in British Columbia, Canada. The large field of view allows CHIME/FRB to be an exceptional pulsar and rotating radio transient (RRAT) finding machine, despite saving only the metadata of incoming Galactic events. We have developed a pipeline to search for pulsar/RRAT candidates using density-based spatial clustering of applications with noise (dbscan), a clustering algorithm. Follow-up observations are then scheduled with the more sensitive CHIME/Pulsar instrument capable of near-daily high-time resolution spectra observations. We have developed the CHIME/Pulsar Single Pulse Pipeline to automate the processing of CHIME/Pulsar search-mode data. We report the discovery of 21 new Galactic sources, with 14 RRATs, 6 isolated long-period pulsars, and 1 binary system. Owing to CHIME/Pulsar’s observations, we have obtained timing solutions for 8 of the 14 RRATs along with all the regular pulsars and the binary system. Notably, we report that the binary system is in a long orbit of 412 d with a minimum companion mass of 0.1303 solar masses and no evidence of an optical companion within 10″ of the pulsar position. This highlights that working synergistically with CHIME/FRB’s large survey volume CHIME/Pulsar can obtain arc second localizations for low-burst rate RRATs through pulsar timing. We find that the properties of our newly discovered RRATs are consistent with those of the presently known population. They tend to have lower burst rates than those found in previous surveys, which is likely due to survey bias rather than the underlying population.