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Quartz fiber irradiation tests. Irradiation test: UCL, Louvain-la- Neuve , June 2013.
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Irradiation test: UCL, Louvain-la-Neuve, June 2013 Performed 25-Jun-2013 at UCL, Louvain-la-Neuve*. Two fiber types, both 200 µm q-q: FVP200220240 from Polymicro and MIS-166 (with copper coating) from Fryazino (Russia) (thanks to Yu. Chamorovsky for the samples). Each sample was 5 m long, in a Ø5.5 cm spool. irradiation zone samples Particles: protons Energy: 62 MeV dE/dx (quartz): 9 MeV / (g/cm2) flux 2·108 p/cm2/s dose rate: 28 rad/s duration: ~10 hours beam Light source: LED Multicomp OVL-5523 (460 nm) Sensor: HAMAMATSU PIN photodiode S1223-01 Continuous monitoring of attenuation, in DC mode. fiber spool is here * This test was supported by AIDA: FP7 Research Infrastructures project AIDA, grant agreement no. 262025
Irradiation test: UCL, Louvain-la-Neuve, June 2013 Residual damage damage/annealing depth at 28 rad/s Fast damage/annealing cycles at beam on/off. Residual (after 20-30 min annealing) damage grows ~linear with dose. Depth of damage/annealing cycles at 28 rad/s: ~sqrt(dose). For LHCb dose rates (< 0.01 rad/s): the damage is expected to be ≈ the “residual” one==> both fibers are good for us (<1%/m for 100 krad). No clear statement in literature. The dose rate dependence was studied in another irradiation test in UCL, 01/07/2014.
Irradiation test: UCL, Louvain-la-Neuve*, July 2014 The old sample (850 krad in 2013, one year annealing) was used. Five values of dose rate: 29, 0.31, 0.94, 2.9, 8.6 rad/s, then again 0.3 (check). The “rate effect” is ~ (dose rate)2/3. For LHCb (<0.01 rad/s) the “rate effect” is going to be negligible, the small “residual” damage (stable, non-annealing component) will be dominant (see prev. slide). Then studies with spectrometer were also performed (still to be analyzed). * This test was also supported by AIDA.