Radiation hardness, excess noise factor and short-term gain instability of vacuum phototriodes for the operation in pseudorapidity range 1.5⩽η⩽3.0 at CMS ECAL

Evolution Studies of the CMS Electromagnetic Calorimeter Endcap Signals

“…Under irradiation, color centers are formed in the glass material of the face-plates, leading to a further decrease in transparency. Transmission losses of ∼10 % under γ radiation for doses expected at |η| ≈ 2.6 have been measured [8,9]. For neutron irradiation up to 7 × 10 15 n/cm 2 , light transmission losses of about ∼10−30 % have been measured [8].…”

“…Transmission losses of ∼10 % under γ radiation for doses expected at |η| ≈ 2.6 have been measured [8,9]. For neutron irradiation up to 7 × 10 15 n/cm 2 , light transmission losses of about ∼10−30 % have been measured [8]. These neutron fluences are at least an order of magnitude larger than expected at the LHC [1].…”