1 / 6

Absolutely Calibrated Tangential Imaging of Divertor R. J. Maqueda X Science LLC

Absolutely Calibrated Tangential Imaging of Divertor R. J. Maqueda X Science LLC. Project Objectives (from proposal) Develop and implement an absolutely calibrated tangential visible imaging system for the lower divertor of NSTX-U.

ingo
Télécharger la présentation

Absolutely Calibrated Tangential Imaging of Divertor R. J. Maqueda X Science LLC

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Absolutely Calibrated Tangential Imaging of Divertor R. J. Maqueda X Science LLC • Project Objectives (from proposal) • Develop and implement an absolutely calibrated tangential visible imaging system for the lower divertor of NSTX-U. • Use this diagnostic during plasma operations in NSTX-U, validate calibrated data and make data available for general team use. • Use data from diagnostic to benchmark edge computer models and obtain indirect measurements of relevant quantities such as the deuterium neutral density and impurity densities (carbon and lithium) in the divertor region. NSTX-U Non-Lab Diagnostic Plans July 26, 2012 PPPL

  2. Absolute calibration is only a small component of funded work • Upgrade of existing diagnostic. • Photometric calibration to be performed in-vessel before and after campaigns. • Physics results from interaction with modeling. • Strong collaboration with LLNL team members. • Need to measure window/mirror transmission (main hardware development effort). lower X-point Shot 132595 LiI (red) LiII (green)

  3. Similar diagnostics used in other experiments Alcator C-Mod, comparison with onion skin model [S. Lisgo et al., J. Nucl. Mater. 337-339, 139 (2005)] DIII-D, measurements during ELMs [M. Groth, et al., Phys. Plasmas 14, 056120 (2007)] Inter-ELM ELM • Many other examples from DIII-D, C-Mod and JET. • Comparisons with UEDGE/DEGAS and OSM/EIRENE.

  4. Diagnostic highly relevant to NSTX-U research • Successful operation of the divertor needs development of appropriate power handling techniques • Further development of the snowflake divertor. • Development and assessment of divertor detachment and performance. • Generation and transport of impurities (and recycling) at the divertor. • Study of 3-D field effects on divertor physics. • Development and implementation of edge computer models (UEDGE/DEGAS or OEDGE/EIRENE).

  5. Some challenges ahead • Use lambertian source to provide reproducible target plate on some days after the run, illuminate plate from outside through fiber light guide (similar to TS system). • Avoid introducing probe into plasma region but perform all measurements behind passive plates. Existing re-entrant tube Lower dome radial port at Bay F

  6. Absolutely Calibrated Tangential Imaging of Divertor Summary • Main physics results from interaction with modeling. • Strong collaboration with LLNL team members (UEDGE+DEGAS2) and/or other models (OSM+EIRENE). • Photometric calibration expected to yield 20% accuracy. • Bright emission lines (Da, LiI @ 678.0 nm) measured at ≥10 kHzLiII @ 548.5 nm, CII @ 657.8 nm, CIII@ 464.7 nm at ~1 kHz.

More Related