Design and assembly of the LTX-ꞵ Soft X-ray and Lyman-?? Toroidal Diagnostic

The Lithium Tokamak Experiment (LTX) - ꞵ is a low aspect ratio spherical tokamak used to test lithium as a plasma facing material. A toroidal soft x-ray/Lyman-?? diagnostic has been commissioned for LTX-ꞵ. The diagnostic was originally designed and built by Johns Hopkins University for use on NSTX-U and is being adapted for use on LTX-ꞵ to help diagnose MHD modes and neutral density profiles for low recycling discharges in LTX-ꞵ. It is composed of five arrays of 20 photodiodes each, consisting of two arrays aimed at the high field side, two arrays aimed at the low field side, and one array aimed at the whole radial span. The array pre-amplifiers were calibrated using a simple LED and diode array setup. Line integrated emission from each diode will be inverted to construct a radial profile. The diagnostic sub-assembly is installed on a tangential port at the midplane of the torus. Two 5 µm beryllium filters are used with two photodiode arrays, one for the high field side and one for the low field side, to retrieve soft x-ray ranges (100eV to 400eV). The toroidal Lyman-?? array is also composed of two diode arrays each with its own narrowband Lyman-?? filters. The design and assembly of the diagnostic are presented in addition to initial data.