title: The upgrade of the Thomson scattering system for measurement on the C-2/C-2U devices.
abstract: The C-2/C-2U Thomson scattering system has been substantially upgraded during the latter phase of C-2/C-2U program. A Rayleigh channel has been added to each of the three polychromators of the C-2/C-2U Thomson scattering system. Onsite spectral calibration has been applied to avoid the issue of different channel responses at different spots on the photomultiplier tube surface. With the added Rayleigh channel, the absolute intensity response of the system is calibrated with Rayleigh scattering in argon gas from 0.1 to 4 Torr, where the Rayleigh scattering signal is comparable to the Thomson scattering signal at electron densities from 1 × 1013to 4 × 1014cm-3. A new signal processing algorithm, using a maximum likelihood method and including detailed analysis of different noise contributions within the system, has been developed to obtain electron temperature and density profiles. The system setup, spectral and intensity calibration procedure and its outcome, data analysis, and the results of electron temperature/density profile measurements will be presented.
authors.affiliation: Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688, USA.
authors.forename: K
authors.initials: K
authors.lastname: Zhai
authors.affiliation: Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688, USA.
authors.forename: T
authors.initials: T
authors.lastname: Schindler
authors.affiliation: Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688, USA.
authors.forename: J
authors.initials: J
authors.lastname: Kinley
authors.affiliation: Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688, USA.
authors.forename: B
authors.initials: B
authors.lastname: Deng
authors.affiliation: Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Thompson