Timing Binary Pulsars with CHIME and the NANOGrav 15yr Dataset

The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) conducts high-precision timing over long timescales of a large number of millisecond pulsars (MSPs) with the goal of detecting the background gravitational wave signature from merging supermassive black hole binaries. Wideband (WB) timing of the NANOGrav datasets was first done in the 12.5yr dataset, and proved to be extremely helpful for measuring the time-varying dispersion measure, which can significantly limit timing precision. However, we are still limited by the fact that NANOGrav only observes most pulsars once per month. In contrast, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Telescope currently observes most NANOGrav MSPs at nearly daily cadence at 600 MHz with a 400 MHz bandwidth. Using WB timing techniques, we combined two years of data taken at CHIME with the NANOGrav 15yr Dataset for four MSPs to investigate how the measurement of post-Keplerian and astrometry parameters benefit from the high cadence observing campaigns. This data combination will also pave the way for larger analyses in the future.