Studies of the radiation hardness of lead tungstate crystals produced by the Bogoroditsk Techno-Chemical Plant in Russia and the Shanghai Institute of Ceramics in China have been carried out at IHEP, ...Protvino. The crystals were irradiated by a 40-GeV pion beam. After full recovery, the same crystals were irradiated using a \(^{137}Cs\) \(\gamma\)-ray source. The dose rate profiles along the crystal length were observed to be quite similar. We compare the effects of the two types of radiation on the crystals light output.
The energy dependence of the energy and position resolutions of the electromagnetic calorimeter prototype made of lead tungstate crystals produced in Bogoroditsk (Russia) and Shanghai (China) is ...presented. These measurementswere carried out at the Protvino accelerator using a 1 to 45 GeV electron beam. The crystals were coupled to photomultiplier tubes. The dependence of energy and position resolutions on different factors as well as the measured electromagnetic shower lateral profile are presented.
We report on the effects of radiation on the light output of lead tungstate crystals. The crystals were irradiated by pure, intense high energy electron and hadron beams as well as by a mixture of ...hadrons, neutrons and gammas. The crystals were manufactured in Bogoroditsk, Apatity (both Russia), and Shanghai (China). These studies were carried out at the 70-GeV proton accelerator in Protvino.
A beam line for electrons with energies in the range of 1 to 45 GeV, low contamination of hadrons and muons and high intensity up to 10^6 per accelerator spill at 27 GeV was setup at U70 accelerator ...in Protvino, Russia. A beam tagging system based on drift chambers with 160 micron resolution was able to measure relative electron beam momentum precisely. The resolution sigma_p p was 0.13% at 45 GeV where multiple scattering is negligible. This test beam setup provided the possibility to study properties of lead tungstate crystals (PbWO_4) for the BTeV experiment at Fermilab.
The reaction $\pi^-p \to \eta\pi^o n$ has been studied with GAMS-2000
spectrometer in the secondary 38 GeV/c $\pi^-$-beam of the IHEP U-70
accelerator. Partial wave analysis of the reaction has been ...performed in the
$\eta\pi^o$ mass range up to 1200 MeV. The $a_0(980)$-meson is seen as a sharp
peak in S-wave. The $t$-dependence of $a_0(980)$ production cross section has
been studied. Dominant production of the $a_0(980)$ at a small transfer
momentum $t$ confirms the hypothesis of Achasov and Shestakov about significant
contribution of the $\rho_2$ exchange ($I^GJ^{PC}=1^+2^{--}$) in the mechanism
of $a_0(980)$ meson production in $t$-channel of the reaction.
The reaction \(\pi^-p \to \eta\pi^o n\) has been studied with GAMS-2000 spectrometer in the secondary 38 GeV/c \(\pi^-\)-beam of the IHEP U-70 accelerator. Partial wave analysis of the reaction has ...been performed in the \(\eta\pi^o\) mass range up to 1200 MeV. The \(a_0(980)\)-meson is seen as a sharp peak in S-wave. The \(t\)-dependence of \(a_0(980)\) production cross section has been studied. Dominant production of the \(a_0(980)\) at a small transfer momentum \(t\) confirms the hypothesis of Achasov and Shestakov about significant contribution of the \(\rho_2\) exchange (\(I^GJ^{PC}=1^+2^{--}\)) in the mechanism of \(a_0(980)\) meson production in \(t\)-channel of the reaction.
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