TJ-II: Injection of TESPELs with compounds or multiple elements of interest for W7-X

Experimental campaign

Spring 2022

Proposal title

Injection of TESPELs with compounds or multiple elements of interest for W7-X

Name and affiliation of proponent

René Bussiahn, IPP-Greifswald

Details of contact person at LNF

Kieran J McCarthy

Description of the activity

Motivation and Background

Inject TESPELs containing compounds of interest (e.g. Li2CO3) and atomic elements (Al, Ti, Fe Cu, Ni, Mn, W) that are candidates for use in the OP2.1 campaign in W7-X. The principal aim is to identify strong emission lines from the atomic states of these elements in order to prepare filterscopes for the W7-X TESPEL system. You can use references, e.g, .

Proposal Objectives

We will prepared 300 um diameter TESPELs at the Ciemat laboratory and fill these will small quantities of the different tracers of interest. It is intended to inject these into ECRH heated plasmas on TJ-II so that the polystyrene outer shell will have been evaporated when the TESPEL is in the plasma core. The tracers are then exposed to the plasma and atomic line emissions will be recorded using a compact UV-visible spectrometer located in the same TJ-II sector. This will allow identifying the strong emissions lines from each element.

Approach and Methodology

ECRH plasmas are best for this, albeit it might be possible to perform these measurements also in NBI plasmas (the TESPEL penetration depth is large in NBI plasmas so the TESPEL may exit the plasma without exposing the tracers). Standard magnetic configuration with ECRH off-axis to avoid density cut-off.

International or National funding project or entity

Include funding here (grants, national plans)

Description of required resources

Required resources:

• Number of plasma discharges or days of operation:
• Essential diagnostic systems (without which, the proposal cannot be conducted):
• Other diagnostic system of special interest:
• Type of plasmas (heating and magnetic configuration):
• Specific requirements on wall conditioning if any:
• External users: need a local computer account for data access: yes/no
• Any external equipment to be integrated? Provide description and integration needs:

Preferred dates and degree of flexibility

Preferred dates: (format dd-mm-yyyy)

(If remote participation is required or preferred, please, indicate it here. A Zoom connection with the local contact person will be arranged on the day of experiments.)

References

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