HAWC J0630+186 Could Not Be Powered by PSR J0630+19

TL;DR

This study used FAST radio telescope observations to analyze PSR J0630+19, concluding it lacks sufficient energy to power the nearby gamma-ray source 3HWC J0630+186, thus challenging their association.

Contribution

The paper provides precise pulsar parameters showing PSR J0630+19 cannot be the source of the gamma-ray emissions, clarifying the origin of 3HWC J0630+186.

Findings

PSR J0630+19 is an old pulsar with low energy loss.

The pulsar cannot power the gamma-ray source 3HWC J0630+186.

Precise pulsar parameters were obtained through FAST observations.

Abstract

3HWC J0630+186 is one of the very-high-energy gamma-ray sources in the third High-Altitude Water Cherenkov (HAWC) catalog, its origin and source are, however, not clearly identified. The only possible associated source is PSR J0630+19 depart from the center of 3HWC J0630+186. A few TeV halos of pulsars are currently believed the most dominant TeV-PeV gamma-ray sources, and PSR J0630+19 was firstly discovered by Arecibo survey with normal pulsar period, but its age and spin-down luminosity are not available. It is then difficult to determine if 3HWC J0630+186 and PSR J0630+19 are associated or not. With the awarded telescope time in five-hundred-meter aperture spherical radio telescope (FAST) observing cycle, we have obtained the follow-up timing observations of PSR J0630+19 with observed duration more than one year. From our pulsar data analysis, we determined a more precise position and derived parameters via pulsar timing. The parameters indicate that it is an old pulsar with energy loss too low to power the very-high-energy emissions from 3HWC J0630+186.