| 1. |
- Abt, I, et al.
(författare)
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Inclusive V-0 production cross sections from 920 GeV fixed target proton-nucleus collisions
- 2003
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 29:2, s. 181-190
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Tidskriftsartikel (refereegranskat)abstract
- Inclusive differential cross sections dsigma(pA)/dx(F) and dsigma(pA)/dp(t)(2) for the production of K-S(0), Lambda, and (&ULambda;) over bar particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to roots = 41.6 GeV in the proton-nucleon system. The ratios of differential cross sections dsigma(pA)(K-S(0))/dsigma(pA)(Lambda) and dsigma(pA)((&ULambda;) over bar)/dsigma(pA) (Lambda) are measured to be 6.2 +/- 0.5 and 0.66 +/- 0.07, respectively, for x(F) approximate to -0.06. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions da,Ald t also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections sigma(pA) on the atomic mass A of the target material is discussed, and the deduced cross sections per nucleon sigma(pN) are compared with results obtained at other energies.
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| 2. |
- Abt, I, et al.
(författare)
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Measurement of the b(b)over-bar production cross section in 920 GeV fixed-target proton-nucleus collisions
- 2003
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 26:3, s. 345-355
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Tidskriftsartikel (refereegranskat)abstract
- Using the HERA-B detector, the b (b) over bar production cross section has been measured in 920 GeV proton collisions on carbon and titanium targets. The b (b) over bar production was tagged via inclusive bottom quark decays into J/psi by exploiting the longitudinal separation of J/psi --> l(+)l(-) decay vertices from the primary proton-nucleus interaction. Both e(+)e(-) and mu(+)mu(-) channels have been reconstructed and the combined analysis yields the cross section sigma(b (b) over bar) = 32(-12)(+14)(stat) (+6)(-7)(sys) nb/nucleon.
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| 3. |
- Ryzhikov, V. D., et al.
(författare)
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Behavior of new ZnSe(Te,O) semiconductor scintillators under high doses of ionizing radiation
- 2001
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Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 48:4, s. 1561-1564
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Tidskriftsartikel (refereegranskat)abstract
- Changes in scintillation and optical properties of scintillators based on ZnSe(Te,O) crystals were studied under influence of ionizing radiations: gamma (similar to1.3 MeV, up to 500 Mrad), protons (similar to 18 MeV, fluence up to 10(16) per cm(-2)), electrons (0.54-2.26 MeV, up to 50 Mrad), and neutrons (source-thermal reactor channel, fluence up to 1016 per cm(2)). Light output of gamma-irradiated scintillator crystals ZnSe(Te,O) was shown to decrease by less than 10-12% under doses of 100 Mrad, with transparence in the visible range worse by only 10-12%. Effects of electron irradiation are similar. Under neutron irradiation of crystals, increase in their light output by 20-150% is observed, with nontrivial changes of optical characteristics in the visible and infrared (IR) spectral ranges. Proton irradiation caused the most sharp degradation of scintillation properties of ZnSe(Te,O) crystals, with selective absorption bands appearing in the ER (4-7 mum) region. Accounting for the role of recombination centers related to zinc vacancies and properties of interstitial zinc atoms, a model is considered of radiation-stimulated processes in ZnSe(Te,O) semiconductor scintillators.
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