The results from studying the time characteristics (counting, amplitude distributions of single-electron pulses, spread of the signal propagation time (jitter) when exposed to radiation from picosecond diode lasers in the spectral range 405–780 nm) of high-speed photomultipliers FEU-175 and FEU-186 manufactured by AO Central Research Institute Electron (St. Petersburg). FEU-175 and FEU-186, respectively, are equipped with bialkali and multialkali photocathodes; their operating spectral range is 250–650 and 250–800 nm, respectively. Signal amplification is provided by a 14-dynode multiplication system, while the rise time of the PMT impulse response does not exceed 1.5 ns and the jitter is approximately 0.4 ns. PMT data can be used as photodetectors in single-quantum kinetic spectrometers with subnanosecond resolution and in other high-speed optoelectronic recorders.

The energy resolution σ/E of the electromagnetic calorimeter (ECAL) in the energy range of 50–500 GeV is defined mainly by two terms: stochastic α/√E and constant C. The photoreadout of the CMS Endcap ECAL consists of vacuum phototriodes (VPT), which are broadening a signal from np photoelectrons characterized by the excess noise factor F=np(σ/E)2. The technical specification of the CMS ECAL requires the value of F to be smaller than 4 in the CMS LHC environment during 10 years of detector operation. In this paper we present results of the VPT performance study in a magnetic field up to 4 T, in a gamma radiation field of 0–50 kGy and in a neutron fluence of 7×1015n/cm2. The standard phototriodes FEU-188 with faceplates from UV glass used in CMS ECAL as well as VPTs with super radiation hard cerium-doped glasses were investigated at the 60Co gamma facility, a neutron generator and a nuclear reactor in the Petersburg Nuclear Physics Institute (PNPI). The dependence of the VPT gain and the excess noise factor in magnetic fields on the fine-mesh plane orientation has also been studied.

The behaviour of fine-mesh vacuum phototriodes (VPTs) with the external diameters of 21 and 25 mm has been investigated in an axial magnetic field up to 4 T in view of their applications as readout devices for CMS Endcap Electromagnetic Calorimeter. The measured VPT parameters are: the photocathode's sensitivity and its homogeneity, the gain in zero and 4 T magnetic field at tilt angles corresponding to the pseudorapidity range of CMS ECAL Endcap 1.48–3.0 as a function of fine-mesh cell dimensions, excess noise factor and the stability of the photocathode response under the illumination by light emission diodes (LED) and the irradiation by 14 MeV neutrons. Phototriodes with 100 lines per mm fine-mesh and 25 mm external diameter are found to be the best candidates for coupling with rear PbWO4 crystals by dimensions of 30×30 mm, proposed to be used in CMS ECAL Endcaps. VPTs provide a gain of the order (6–8) in a 4 T magnetic field and an excess noise factor of 2–2.5 under illumination of a full photocathode's area.

The last years' developments of Photomultiplier Tubes (PMTs) in the “Electron” National Research Institute are presented. There were a number of PMTs with superior characteristics developed during the last decade. Among these are such devices as PMTs with low radiation background, microchannel plate PMTs (MCP-PMT), PMTs with GaAs photocathodes. The latest developments of the new kind and innovative range of photodetectors, and such novel devices as Fine-Mesh PMTs for high magnetic field environment and proximity focused Hybrid PMTs (HPMT) with an electron bombarded p-i-n diode are also discussed.

We report the results of tests of prototype proximity mesh dynode photomultiplier tubes (FEU-527) manufactured by MELS. These tubes were compared with similar Hamamatsu models R5505/R3432-01 to determine their suitability for use in the Time-of-Flight (TOF) subsystem of the Solenoidal Tracker at RHIC (STAR) project. Gain and timing characteristics of these tubes were measured both with and without a magnetic field. The results show that some of the Russian prototype tubes meet the requirements for the STAR TOF subsystem.

Future experiments on RHIC and LHC require the performance of photodetectors with stable operation in strong magnetic fields, 0.5 T for the STAR (RHIC) Time of Flight system (TOF) and more than 3 T for the CMS (LHC) electromagnetic calorimeter. Such photodetectors have to possess a good energy and time resolution, for TOF measurements less than 100 ps [1] simultaneously being radiation hard up to some Mrad. Fine mesh dynode proximity photomultiplier tubes FMPMT developed and produced in recent years by Hamamatsu are the most promising detectors for the above specified goals. Different kinds of PMT were tested by some experimental groups in axial magnetic field up to 1.5 T [2–4]. The obtained PMT time resolution in beam test together with Bicron scintillator was better than 100 ps [1].