NICER observation list: Target ID 360202

We request 15 NICER observations of exposure 2 ks each (total exposure of 30 ks) of the low mass X-ray binary Her X-1 during the main-on phase of its 35 day superorbital cycle. NICER's high throughput, timing resolution, and lack of pile up will allow us to observe the 10 day bright main-on phase with excellent statistics and high observing cadence. We will observe changes in the soft pulse profile and model these changes using an irradiated warped disk model. With these observations we will place strong constraints on the geometry of the accretion disk and will also probe the assumption that disk precession smoothly modulates the soft pulse profiles for the first time, revealing important information about the kinematics of disk structures in accreting compact objects.