Experimental study of ELM induced fast-ion transport using passive FIDA spectroscopy at the ASDEX Upgrade tokamak

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F21%3A00555299" target="_blank" >RIV/61389021:_____/21:00555299 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.1088/1741-4326/abd4b7" target="_blank" >https://iopscience.iop.org/article/10.1088/1741-4326/abd4b7</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1741-4326/abd4b7" target="_blank" >10.1088/1741-4326/abd4b7</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Experimental study of ELM induced fast-ion transport using passive FIDA spectroscopy at the ASDEX Upgrade tokamak

Popis výsledku v původním jazyce

Measurements using a recently installed edge fast-ion D-alpha (FIDA) diagnostic at the ASDEX Upgrade tokamak show a clear effect of edge localised modes (ELMs) on the passive FIDA signals. While a reduction in the passive FIDA emission is observed in the scrape-off layer (SOL) region, measurements close to the last closed flux surface show an increase in signals shortly after ELMs, followed by a decrease. The decrease provides a clear sign of fast-ion losses in the SOL, while the increase can be explained by an enhanced neutral density during ELMs inside the plasma. In addition, small ELMs are observed, which barely change the neutral density and plasma position but still cause significant changes in the passive FIDA signals. A comparison of the measurements with forward modelling shows that 60% to 80% of the fast ions are lost by ELMs outside the last closed flux surface. In addition, a 20% decrease of the fast-ion density in a range up to 4 cm within the last closed flux surface can be inferred. This range agrees well with the latest modelling results of ELMs using the non-linear MHD code JOREK and shows that less than 0.3% of all fast ions are lost by ELMs.

Název v anglickém jazyce

Experimental study of ELM induced fast-ion transport using passive FIDA spectroscopy at the ASDEX Upgrade tokamak

Popis výsledku anglicky

Measurements using a recently installed edge fast-ion D-alpha (FIDA) diagnostic at the ASDEX Upgrade tokamak show a clear effect of edge localised modes (ELMs) on the passive FIDA signals. While a reduction in the passive FIDA emission is observed in the scrape-off layer (SOL) region, measurements close to the last closed flux surface show an increase in signals shortly after ELMs, followed by a decrease. The decrease provides a clear sign of fast-ion losses in the SOL, while the increase can be explained by an enhanced neutral density during ELMs inside the plasma. In addition, small ELMs are observed, which barely change the neutral density and plasma position but still cause significant changes in the passive FIDA signals. A comparison of the measurements with forward modelling shows that 60% to 80% of the fast ions are lost by ELMs outside the last closed flux surface. In addition, a 20% decrease of the fast-ion density in a range up to 4 cm within the last closed flux surface can be inferred. This range agrees well with the latest modelling results of ELMs using the non-linear MHD code JOREK and shows that less than 0.3% of all fast ions are lost by ELMs.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Nuclear Fusion

ISSN

0029-5515

e-ISSN

1741-4326

Svazek periodika

61

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

AT - Rakouská republika

Počet stran výsledku

12

Strana od-do

046001

Kód UT WoS článku

000624498300001

EID výsledku v databázi Scopus

2-s2.0-85103209068