NICER observation list: Target ID 653501

SMC X-1 is thought to have a warped, precessing accretion disk (as evidenced by superorbital period modulations that range from 45-60 days). This implies that the accretion disk configuration is changing during this time. Previous work has well demonstrated that the shape of the soft pulse periods (i.e. the reprocessed emission) changes within a single 60 day cycle. The superorbital period began in 2020 and ended in 2022, with NICER monitoring throughout the second half of the excursion. This proposed program would use NICER to monitor the past-excursion observations, including spectral shape and pulse profiles of SMC X-1 to act as a benchmark as the superorbital period takes a rare excursion and use this exceptional dataset to probe the physics of this warped, precessing accretion disk.