TY - JOUR
T1 - A 1D Lyman-alpha profile camera for plasma edge neutral studies on the DIII-D tokamak
AU - Rosenthal, A. M.
AU - Hughes, J. W.
AU - Bortolon, A.
AU - Laggner, F. M.
AU - Wilks, T. M.
AU - Vieira, R.
AU - Leccacorvi, R.
AU - Marmar, E.
AU - Nagy, A.
AU - Freeman, C.
AU - Mauzey, D.
N1 - Publisher Copyright:
© 2021 Author(s).
PY - 2021/3/1
Y1 - 2021/3/1
N2 - A one dimensional, absolutely calibrated pinhole camera system was installed on the DIII-D tokamak to measure edge Lyman-alpha (Ly-α) emission from hydrogen isotopes, which can be used toinfer neutral density and ionization rate profiles. The system is composed of two cameras, each providing a toroidal fan of 20 lines of sight, viewing the plasma edge on the inboard and outboard side of DIII-D. The cameras' views lie in a horizontal plane 77 cm below the midplane. At its tangencyradius, each channel provides a radial resolution of ∼2 cm full width at half maximum (FWHM) with a total coverage of 22 cm. Each camera consists of a rectangular pinhole, Ly-α reflective mirror, narrow-band Ly-α transmission filter, and a 20 channel AXUV photodetector. The combined mirror and transmission filter have a FWHM of 5 nm, centered near the Ly-α wavelength of 121.6 nm and is capable of rejecting significant, parasitic carbon-III (C-III) emission from intrinsic plasma impurities. To provide a high spatial resolution measurement in a compact footprint, the camera utilizes advanced engineering and manufacturing techniques including 3D printing, high stability mirror mounts, and a novel alignment procedure. Absolutely calibrated, spatially resolved Ly-α brightness measurements utilize a bright, isolated line with low parasitic surface reflections and enable quantitative comparison to modeling to study divertor neutral leakage, main chamber fueling, and radial particle transport.
AB - A one dimensional, absolutely calibrated pinhole camera system was installed on the DIII-D tokamak to measure edge Lyman-alpha (Ly-α) emission from hydrogen isotopes, which can be used toinfer neutral density and ionization rate profiles. The system is composed of two cameras, each providing a toroidal fan of 20 lines of sight, viewing the plasma edge on the inboard and outboard side of DIII-D. The cameras' views lie in a horizontal plane 77 cm below the midplane. At its tangencyradius, each channel provides a radial resolution of ∼2 cm full width at half maximum (FWHM) with a total coverage of 22 cm. Each camera consists of a rectangular pinhole, Ly-α reflective mirror, narrow-band Ly-α transmission filter, and a 20 channel AXUV photodetector. The combined mirror and transmission filter have a FWHM of 5 nm, centered near the Ly-α wavelength of 121.6 nm and is capable of rejecting significant, parasitic carbon-III (C-III) emission from intrinsic plasma impurities. To provide a high spatial resolution measurement in a compact footprint, the camera utilizes advanced engineering and manufacturing techniques including 3D printing, high stability mirror mounts, and a novel alignment procedure. Absolutely calibrated, spatially resolved Ly-α brightness measurements utilize a bright, isolated line with low parasitic surface reflections and enable quantitative comparison to modeling to study divertor neutral leakage, main chamber fueling, and radial particle transport.
UR - https://www.scopus.com/pages/publications/85102316556
UR - https://www.scopus.com/inward/citedby.url?scp=85102316556&partnerID=8YFLogxK
U2 - 10.1063/5.0024115
DO - 10.1063/5.0024115
M3 - Article
C2 - 33820041
AN - SCOPUS:85102316556
SN - 0034-6748
VL - 92
JO - Review of Scientific Instruments
JF - Review of Scientific Instruments
IS - 3
M1 - 033523
ER -