Title: Modeling of a Laser-Induced Rydberg Spectroscopy diagnostic for Direct Measurement of the Local Electric Field in the Edge Region of NSTX/NSTX-U Contributors: Reymond, L.Diallo, A.Vekselman, V.U. S. Department of Energy contract number DE-AC02-09CH11466 Keywords: Electric field Issue Date: Jul-2018 Publisher: Princeton Plasma Physics Laboratory, Princeton University Related Publication: Review of Scientific Instruments (July 2018) Abstract: We discuss a novel diagnostic allowing direct measurements of the local electric field in the edge region in NSTX/NSTX-U. This laser based diagnostic's principle consists of depleting the naturally populated $n=3$ level to a Rydberg state --sensitive to electric fields-- that will result in a suppression of part of the $D_{\alpha}$ emission. We refer to this approach as Laser-Induced Rydberg Spectroscopy (LIRyS). It is shown that the local electric field can be measured through the Stark induced resonances observed as dips in the $D_\alpha$ emission. Using forward-modeling of simulated absorption spectra, we show precisions reaching \SI{\pm 2}{\kilo\volt\per\meter} in regions with a local electric field of \SI{15}{\kilo\volt\per\meter}. URI: http://arks.princeton.edu/ark:/88435/dsp01c247dv80k Appears in Collections: NSTX-U