Measurements and calculations of electron avalanche growth in ternary mixtures of Ne + CO2 + N2
Presented by Dr. Tadeusz KOWALSKI on 13 Oct 2015 from 16:25 to 16:25
Session: Poster session & coffee break
Track: Simulation and Software
Board #: 47
The ternary gas mixtures of Ne + CO2 + N2 is used in TPC, in the main tracking detector of ALICE at LHC accelerator. This mixture has a small diffusion constants, small thickness, reasonable value of electron drift velocity, small multiple scattering. A small addition of N2 increases the electron drift velocity and reduces the micro-sparking. In this mixtures, besides the direct ionization, gas multiplication is enhanced by Penning transfer both with CO2 and N2. Up to now, the range of measured gas gain is limited by 2*10^3 – 5*10^4. In this work, we want to present the gas gain curves in a wide range beginning from the ionization regime to the breakdown limit (few * 10^5), for mixtures pressures from 400 hPa to 1800 hPa, gas composition of Ne + CO2 (10%) + N2 (2.5 ; 5 and 7.5%, respectively) and for Ne + N2 (2.5; 5 and 7.5%, respectively). The measured data have been fitted using Magboltz simulation program to determine the Penning transfer rates.
Location: Trieste - Italy
Address: Congress Centre Stazione Marittima Molo Bersaglieri, 3 34123 Trieste Italy