SOL transport - proposal discussion

Friday 11 Mar 2022, 13:50 → 15:00 Europe/Berlin

zoom room 1: ID: 977-8365-2575 / PW: 011214

Valeria Perseo (IPP-Greifswald)

2nd meeting to discuss the single proposal planning.

Zoom room 1

1 Proposal: ion temperature measurements with RFA

Speaker: Jie Yang

proposal for SOL transport_yang.pptx

Discussion on proposals by Jie Yang, SOL transport proposals for Ti measurements
investigation of different magnetic configurations
Ti/Te ratio in dependence of density, ECRH and ICRH heating
power density scan, maybe the ECRH can be done piggy back? maybe also ICRH can be done piggy back
Note that ICRH is not going to be routinely available in OP2.1, at least at the start, so ICRH related proposal will need dedicated experimental time.
MPM has filter for the RFA probe for ICRH operation
ion temperature measurements related to SOL turbulence also planned

2 Proposal: upstream characterization

Speaker: Erik Flom

Flow_UpstreamCharacterization.pptx

Discussion on proposals by Erik Flom Upstream characterization towards 2pt model validation M

PM plunges --> radial coverage can be minimum invasive, best if the radial coverage is investigated during commissioning phase but it is not clear yet at what depth the probe becomes perturbative

insertion in the plasma actually lasts rougly 100 ms, 0.5 s is the whole movement

possible to insert NBI blips for info on impurity content, even a single blips per power step (one blip is 30 ms), can be put into final MPM plunge while probe is being removed

possible combination with radiation characterization and transition to small plasmas proposal

can also provide information for P. Drews discharges investigating helium buildup in island proposal

has good overlap with F. Reimold proposed EMC3 reference experiments (similar power/density settings, E. Flom proposes only Standard config, EMC3 references would extend to include other magnetic configuraitons, notably 10/10 and low iota)

3 Proposal: effect of beta and helium puffing on Ti/Te

Speaker: Philipp Drews

proposal_sol_transport_drews.pptx

Discussion on proposals by Philipp Drews
Ti/Te ratio with beta and with helium puffing
beta effect on edge transport
measurement of He accumulation in island? idea: change in radiation profile + HEXOS. Problem: absolute rise of He in HEXOS signal can be only because He is not pumped out
ERO calculations have been used up to now to assess the island He accumulation
Maybe more info from He beam? but magnitude of intensity increase might not be enough to be detectable
Proposals can be affected by cryopoumps, so maybe request of on-off cycles
MPM probably will have multiple heads with Ti measurement of some sort

4 Proposal: reference program for EMC3-Eirene comparison

Speaker: Felix Reimold (IPP)

Discussion on proposal by Felix Reimold on EMC3-Eirene reference
test puff: for test-impurity approach, on top of N continuos puff to keep f_rad constant
MPM: pay attention to probe head, but repeating the experiment for different probe heads could give info on repeatibility of the conditions
problem with current? if the current evolution is not drastic, there is a limit of movement of the island (whether it is only a strike line shift or a complete change in the SOL geometry), put still open point
empirical limit from Carsten: 6 kA
from planar coils, iota change acceptable: 1 kA
other option: going to saturation first but that takes time (developing a way to reach to saturation faster? ECCD? maybe need to put this in the requirements for the proposal to be run)