11th International Workshop on Ring Imaging Cherenkov Detectors (RICH2022)

C4F10 in COMPASS RICH-1

15 Sept 2022, 09:00

25m

University of Edinburgh

presentation Technological aspects and applications Technological aspects and applications of Cherenkov detectors

Speaker

S. Dalla Torre (Universita e INFN Trieste (IT))

Description

C4F10 in COMPASS RICH-1
A Liberec-Prague-Trieste collaboration

Abstract:

COMPASS RICH-1 is using high-purity C4F10 as radiator gas since 2001. The operation and control of the radiator gas has evolved over years with continuous improvements.
We report on the experience gained in the 20 year-long operation of C4F10 as COMPASS RICH radiator.

C4F10 procurement is becoming challenging, and the minimization of material waste is now a priority for the protection of the environment. Commercially available C4F10 needs dedicated filtering before usage and typical material losses in the filtering procedure are around 30%. Recent efforts allowed to reduce them to about 5%.
Very accurate values for the radiator gas refractive index are needed for high-performance particle identification. The procedure has evolved over years and the one presently in use, which provides refractive index estimate at the 1 ppm level, is discussed.
A new system, based on a modified folded Jamin interferometer, has been recently built. It will provide very precise online monitoring of the COMPASS RICH-1 gas radiator refractive index.

Presentation materials

RICH2022_C4F10_dallatorre.pdf