NICER Mission Overview
Astrophysics on the International Space Station - Understanding ultra-dense matter through soft X-ray timing
An established platform and a benign environment
The ISS offers:
High-throughput, low-background soft X-ray timing and spectroscopy
Neutron Stars - Unique environments in which all four fundamental forces of Nature are simultaneously important
Reveal stellar structure through lightcurve modeling, long-term timing, and pulsation searches
Lightcurve modeling constrains the compactness (M/R) and viewing geometry of a non-accreting millisecond pulsar through the depth of modulation and harmonic content of emission from rotating hot-spots, thanks to gravitational light-bending...
Simulations demonstrate how well an assumed neutron star radius can be recovered. The +5% (3σ) measurement goal is attained in less than 1 Msec.
The resulting allowed regions in the M-R plane rule out proposed families of neutron star equations of state. The best mass measurements alone can't distinguish among competing models.
Neutron Star Science Synergies
Interplay between multiwavelength capabilities amplifies scientific returns from all
Guest Observer Program
Sample science enabled by the NICER GO program
Redshifted Fe lines from galaxy clusters reveal star-formation history and poorly understood feedback processes that drive galaxy evolution. (Left) A z = 1.18 line is seen well above the diffuse X-ray back-ground (blue).