The amount of tritium (T) retained in plasma facing components (PFCs) and in-vessel structures has to be carefully monitored in ITER because of the limits fixed by safety issues. Laser-Induced-Breakdown-Spectroscopy (LIBS) is one of the eligible techniques for this task because it does not require any sample pre-treatment (or removal), it can work both in atmospheric pressure or in vacuum, with different background gases. LIBS can be set up both on a robotic arm entering the vacuum vessel or outside it, for analyses during shut-down periods or in-between plasma discharges. In this paper we describe a new, compact LIBS system, mounted on the Frascati Tokamak Upgrade (FTU) robotic arm, to perform measurements on ITER-relevant samples placed in the FTU mock-up. The samples, composed of thin layers (few μm) of W, Al, D, simulate the co-deposition of Be with T on ITER divertor tiles (Be and T are replaced by Al and D in the samples). W, Al, D emission lines has been clearly detected, both as major constituents or in trace quantities, with different background gases using a single laser pulse.
|Titolo:||LIBS measurements inside the FTU vessel mock-up by using a robotic arm|
|Data di pubblicazione:||2020|
|Appare nelle tipologie:||1.1 Articolo in rivista|