The Rocket Experiment Demonstration of a Soft X-ray Polarimeter (REDSoX) proposal was selected and funded. REDSoX is a sounding rocket payload designed primarily to demonstrate the technology needed to measure linear X-ray polarization as a function of energy below 1 keV and secondarily to probe the relativistic jets of blazars. MSFC's role is to design, build, vibration test, and x-ray calibrate one 0.5 m diameter, 5-shell mirror module that will be the primary mirror of the instrument. Herman Marshall at MIT is the PI and will oversee instrument design, fabrication, and integration. Collaborators at Lawrence Berkeley National Lab will produce laterally graded multilayer optics for the instrument and collaborators at Boston University will provide science support. At MSFC, this project will leverage mirror module design work that was performed and mandrels that were built, though not polished, for the Micro-X project. The Micro-X mandrels are currently in storage at MSFC. The proposed MSFC schedule breaks down as follows:
- FY23 - Design and dynamics simulation
- FY24 - Mandrel polishing, shell replication and assembly
- FY25 - Mandrel polishing, shell replication, and assembly
- FY26 - Assembly, vibration testing, x-ray calibration
- FY27 - Integration/launch support
The REDSoX mirror module assembly is planned to be delivered to MIT in April of 2026 and the payload is planned to fly from White Sands Missile Range in Q3 of CY2027.
In addition, the Large-Format X-ray Zone Plates APRA was also selected and will receive partial funding. Pennsylvania State University's Fabien Grise leads this project which will use the Marshall 100-meter X-ray beamline (Stray Light Test Facility) for testing.
