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The status of the neutrino experiment at the Krasnoyarsk underground reactor is presented. A method for energy calibration of the silicon multidetector is described. The sensitive volume of the detector has been investigated. The response functions of the detector for electrons, γ rays, and α particles have been measured. Preliminary results of background measurements using silicon and germanium detectors are reported. [ABSTRACT FROM AUTHOR]

The results of investigation of n ++ p + pp + silicon detector structures manufactured from p silicon are presented. These detectors demonstrate the effect of internal amplification of a signal (with a gain of 20) with retained properties of the detector as a spectrometric device. An efficient lowering of the energy level for the detected ionizing radiation is demonstrated. [ABSTRACT FROM AUTHOR]

Silicon detectors with a fine segmentation (micropixel and microstrip) are the main type of detectors used in the inner trackers of Large Hadron Collider (LHC) experiments. Due to the high luminosity of the LHC machines they are required to have a fast response to fit the short shaping time of 20 ns and to be radiation hard. Evaluation of silicon microstrip detectors developed for the ATLAS silicon tracker and carried out under collaboration of CERN and Joffe Physico-Technical Institute has shown the reversal of the pulse polarity in the detector response to short-range radiation. Since the negative signal is of about 30%-60% of the maximal positive one, the effect strongly reduces the charge collection efficiency even in nonirradiated detectors. The investigation presents the consideration of the origin of a negative response in Si microstrip detectors and the experimental proof of the model. The study of the effect has been carried out using "baby" strip detectors with a special design: each strip has a window in a metallization, which covers the p+ implant. The scan of a laser across the strips clearly shows that the negative response is observed along the scan in the interstrip gap. As soon as the light spot is placed on the strip p+ implant the negative response disappears and the value of the charge collected by the active strip proportionally increases. A phenomenological model considers the origin of the negative response as the effect of carrier trapping at the Si-SiO2 interface between the strips. [ABSTRACT FROM AUTHOR]

The first results of studies of special strip and pixel silicon detectors are presented. The detector structures allow the creation of high electrical fields (5 × 105 V/cm) near p–n junctions that are powerful enough to initiate an avalanche multiplication of charge carriers. The possibility of internal amplification in a semiconductor detector similar to the proportional amplification in gas counters is shown. The spectrum of α particles from 238Pu (Eα = 5.5 MeV) demonstrates an “amplified” peak at an energy of 70.2 MeV and an energy resolution FWHM = 10.2 MeV. [ABSTRACT FROM AUTHOR]

Abstract: The recent development of a large volume silicon semiconductor detector with high resolution is discussed. We present the results of the experiment on neutrino-electron scattering using a 80kg silicon detector and reactor antineutrinos. A future project with improved sensitivity of a 1000kg silicon detector and an artificial Cr neutrino source is briefly described. [Copyright &y& Elsevier]