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.
We employed two independent methods to study possible damage to the scintillation mechanism in lead tungstate crystals due to irradiation by a 34
V pion beam. Firstly 10 crystals were irradiated ...simultaneously over 30
h by a narrow beam, so that only a small region of each crystal was affected. We studied the effect of the irradiation on the light output non-uniformity. If a localized degradation was observed, it would indicate damage to the scintillation mechanism. Secondly, we detected light output using two phototubes attached to the sides of a crystal. Since these phototubes detect scintillation light only from a small localized region, the effect of transmission loss should be minimal. We did not see any statistically significant evidence for scintillation mechanism damage with either method. The effect is consistent with zero, and the upper limit is 0.5% at 95% C.L.
A beam line for electrons with energies in the range of 1–
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
μm
resolution was able to measure relative electron beam momentum precisely. The resolution
σ
p/
p was 0.13% at
45
GeV
where multiple scattering is negligible. This test beam setup provided a possibility to study properties of lead tungstate crystals (PbWO
4) for the BTeV experiment at Fermilab.
The BTeV electromagnetic calorimeter Brennan, T; Butler, J; Cheung, H ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2002, Volume:
494, Issue:
1
Journal Article
Peer reviewed
The electromagnetic calorimeter for a new Fermilab collider program named BTeV is based on lead tungstate scintillating crystals (PbWO
4). Various properties of crystals manufactured by Russian and ...Chinese companies were measured at the U70 accelerator in Protvino. A dedicated beam momentum tagging system was used to measure the energy and spatial resolution.
We present experimental results on measuring a single spin asymmetry in η-meson production in the interaction of transversely polarized protons and antiprotons at
p
lab
= 200
GeV/
c with a proton ...target in the region 0.2 <
x
F
< 0.7
for
p↑
p,
0.3 < x
F < 0.7 for
p
̄
↑p
and 0.7 <
p
T
< 2.0
GeV/
c. A comparison of single spin asymmetries in π- and η-meson production is made.
The analyzing power ital Asub ital N of proton-proton elastic scattering in the Coulomb-nuclear interference region has been measured using the 200-GeV/ital c Fermilab polarized proton beam. A ...theoretically predicted interference between the hadronic non-spin-flip amplitude and the electromagnetic spin-flip amplitude is shown for the first time to be present at high energies in the region of 1.5times10sup minus3 to 5.0times10sup minus2 (GeV/ital c)sup 2 four-momentum transfer squared, and our results are analyzed in connection with theoretical calculations. In addition, the role of possible contributions of the hadronic spin-flip amplitude is discussed.
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