1. Charge Exchange Analysis Diagnostic Development
The poloidal CXS diagnostic can provide time-evolved radial profiles of B+5 velocity, temperature and density providing a key term to calculating radial electric fields
Current analysis techniques are dependent on background frames before and after DNB pulses to provide an indication of passive B+4 emission, thus limiting the time resolution of the diagnostic, during periods when the plasma in changing, to the beam pulse (50ms)
Goal: To develop alternate techniques that would enable analysis of all time frames, not just those at the beginning and end of beam pulses
Analysis of passive data
and combined active and
passive spectra
Use of separate shot as
background ‘shot’ and
comparison to results
with background frames

2. Evolving Profiles with Line Integrated spectra
7-06 data with DNB indicates CX dominated line integrated spectra (fits well to single temperature)
Temperature Profiles through L-H transition
CX with DNB
Thomson Te
Temperature (eV)
Line Integrated Spectra during DNB
r/a~0.997
B+1
T=0.8001s
(H-mode)
Shot=
r/a
Counts
Temperature evolves through L-H transition
B+4
-- Fit to Spectra

3. Proposal
Run Sets of identical discharges; one with DNB and one without.
Normal Field 5.4T, I~1MA, LSN,ne~ *1020,RF power 1-3MW
Hopefully shots with steady state L-mode segment preceding transition, and then steady H-mode segment after (ex. Shown below)
Compare the line integrated purely passive profiles to the line integrated combined CX and passive profiles
Comparison:
Background subtraction during the Beam discharge
Background subtraction of discharge w/out DNB to discharge w/ DNB
Results of line integrated analysis with DNB.