NICER observation list: Target ID 557503

High-speed, multi-wavelength observations are essential to understand the underlying physics of the accretion process in the sub-second range in XRBs exhibiting short periods of X-ray and optical activity called outbursts. To study the causes of these sudden outbursts, the variability scales in the different wavelengths and the changes in the geometry of the emitting zone, we propose anticipated observations of 6 outbursts with NICER, strictly simultaneous with optical ground-based follow-up. We will make extensive use of the new OPTICAM triple-band optical instrument that already has 14 nights of guaranteed observation time during the period coinciding with AO4. Observations will also be made with optical telescopes to which our team have access.