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The operation of a pressurized ultraviolet photoionization threshold cherenkov counter

Nuclear Instruments and Methods 186:3 (1981) 513-518

Authors:

N Harnew, DI Meyer

Abstract:

We have successfully tested an ultraviolet photoionization Cherenkov counter in a 10 GeV/c pion beam. The counter has been tested to 11 atm pressure for use as a π-K separator. The design and operation of the counter is described. © 1981.
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An amplitude analysis of ππ scattering from new data on the reaction π-p→π+π-n

Nuclear Physics, Section B 157:2 (1979) 250-272

Authors:

MJ Corden, JD Dowell, J Garvey, M Jobes, IR Kenyon, J Mawson, T McMahon, IF Corbett, RJ Esterling, NH Lipman, PJ Litchfield, KCTO Sumorok, G Alexander, S Dagan, Y Gnat, EH Bellamy, MG Green, N Harnew, JB Lister, JR Lister, AW Robertson, BJ Stacey, JA Strong, DH Thomas

Abstract:

We have carried out a partial-wave analysis of ππ scattering in the mass range 1.0 to 2.08 GeV/c2. We find solutions similar to those obtained in previous analyses below 1.8 GeV/c2 but, in addition, we obtain a new solution which does not suffer from violations of unitarity and is compatible with data from other channels. This solution, when continued to 2.08 GeV/c2, shows a g meson with mass and width of 1.734± 0.010 GeV/c2and 0.322±0.035 GeV/c2 respectively, and an h meson with mass 1.935±0.013 GeV/c2and width 0.263±0.057 GeV/c2. The L = 2 partial wave contains the f meson and an additional resonance with parameters m = 1.502±0.025 Gev/c2, Γ = 0.165±0.042 GeV/c2and x = 0.19±0.03. If we associate this state with the f′(1514), our ππ branching fraction is considerably higher than previous determinations. An SU(3) fit to the 2+ nonet yields a mixing angle of 38.4± 1.3°. © 1979.
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AMPLITUDE ANALYSIS OF PIPI SCATTERING FROM NEW DATA ON THE REACTION PI-P-]PI+PI-N

NUCLEAR PHYSICS B 157:2 (1979) 250-272

Authors:

MJ CORDEN, JD DOWELL, J GARVEY, M JOBES, IR KENYON, J MAWSON, T MCMAHON, IF CORBETT, RJ ESTERLING, NH LIPMAN, PJ LITCHFIELD, KCTO SUMOROK, G ALEXANDER, S DAGAN, Y GNAT, EH BELLAMY, MG GREEN, N HARNEW, JB LISTER, JR LISTER, AW ROBERTSON, BJ STACEY, JA STRONG, DH THOMAS
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Calibration of a large multi-element neutron counter in the energy range 8.5-430 MeV

Nuclear Instruments and Methods 156:3 (1978) 411-423

Authors:

JA Strong, MG Green, N Harnew, AW Robertson, DH Thomas, J Garvey, M Jobes, J Mawson, T McMahon, IF Corbett, RJ Esterling, MR Jane

Abstract:

We describe the calibration of a large 60 element neutron counter with a threshold of 2.7 MeV equivalent electron energy. The performance of the counter has been measured in the neutron kinetic energy range 8.5-430 MeV using a neutron beam at the CERN Synchrocyclotron. The results obtained for the efficiency as a function of energy are in reasonable agreement with a Monte Carlo calculation. © 1978.
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Production of A20 and ω* (1675) in the reaction π-p → π+π-π0n at 12 and 15 GeV/c

Nuclear Physics, Section B 138:2 (1978) 235-252

Authors:

MJ Corden, JD Dowell, J Garvey, M Jobes, IR Kenyon, J Mawson, T McMahon, IF Corbett, RJ Esterling, NH Lipman, PJ Litchfield, KCTO Sumorok, G Alexander, S Dagan, Y Gnat, EH Bellamy, MG Green, N Harnew, JB Lister, JR Lister, PV March, AW Robertson, BJ Stacey, JA Strong, DH Thomas

Abstract:

Data on the reaction π-p → π+π-π0 have been taken at 12 and 15 GeV/c with the CERN Omega multiparticle spectrometer. In a 3-pion partial-wave analysis strong production of A20 (1310) and ω* (1675) is observed. Total and differential cross sections are determined and density matrix elements presented as a function of t in the t- and s-channel frames. The energy dependence of A20 production is studied, and a comparison of ω(780), A20(1310) and ω* (1675) production is made. © 1978.
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