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I S- CH9900002 PAUL SCHERRER INSTITUT ISSN 1423-7296 — — March 1999 J PSI • Scientific Report 1998/Volume I Particles and Matter A new compact radiocarbon dating system has been developed at the Ion Beam Physics Laboratory of PSI/ETH in collaboration with an industrial partner (NEC, Middleton, USA). The device exploits a novel method to destroy molecular interference. Beam energies of less than 1 MeV are now sufficient to identify single 14C ions. The cover photo shows the achromatic mass spectrometer that combines magnetic and electrostatic filter elements following the 500 kV Pelletron accelerator. Major components of the spectrometer, the electrostatic deflector, the beam analyzing system and the beam line components have been designed and partly manufactured at PSI. PAUL SCHERRER INSTITUT ISSN 1423-7296 — —— March 1999 LJ Scientific Report 1998 Volume I Particles and Matter ed. by: U. Baltensperger, D. Herlach, P.-R. Kettle, R. Lorenzen CH-5232 Villigen PSI Switzerland Telephone: +41 56 310 21 11 Telefax:+ 41 56 310 21 99 http://www.psi.ch TABLE OF CONTENTS Editorial : 1 Particle Physics 3 Particle Physics News Theory 4 Facility for neutron decay studies with polarized cold neutrons 5 Ring Accelerator Experiments Particle Properties and Decays Commissioning of the PIBETA detector 6 Muonium - antimuonium conversion: Final results 7 Measurement of the transverse polarization of positrons from the decay of polarized muons 8 Search for a neutral particle of mass 33.9 MeV in pion decay 9 A precision measurement of the Michel parameter £" in polarized muon decay 10 Hadron-Hadron and Hadron-Nucleus Reactions Multinucleon pion absorption cross sections on N, Ar and Xe in the A-resonance region 11 Total cross sections of the charge exchange reaction (jt+, n°) on 2H, 3He and 4He across the Delta Resonance 12 Exotic Atoms Direct observation of Coulomb explosion in pionic and muonic atoms 13 The induced pseudoscalar coupling in nuclei: Muon capture on UB and the hyperfine effect 14 Kinetic energy distribution of theup(1S) atoms as a function of density 15 Study of muon catalyzed dd-fusion in D2 and H/D gas mixtures 16 Kinetic energy of jrp-atoms in liquid and gaseous hydrogen 17 Doppler-broadening of gamma rays following muon capture: Search for scalar coupling 18 Investigation of the metastability of the 2s-state in muonic hydrogen 19 Precision measurement of the singlet \ip capture rate via p.- lifetime in hydrogen gas 20 Measuring u.c/3He fusion 21 Injector I Experiments CPAA as an analytical tool in the biological field 22 Precise measurement of the neutron-proton spin correlation parameter at forward angles 23 External Accelerator / Facility Experiments The CPLEAR experiment 24 Brookhaven experiment E865: Studies of rare and searches for forbidden K+-decays 25 The pixel detector and electromagnetic calorimeter of CMS 26 H1 -events with an isolated lepton, large hadronic jets and missing energy 27 Astrophysics 29 HESSI successfully qualified 30 The HESSI Solar Aspect System (SAS) 31 The HESSI Roll Angle System (RAS) 32 Irradiation of titanium and tungsten samples for HESSI project 33 XMM-RGS calibrations completed 34 Improved energy resolution with Giaever junction X-ray detectors 35 Superconducting X-ray detector read-out using a dc SQUID array 36 Operating of the Proton Irradiation Facility - concise summary. 37 Heating of stellar coronae 38 Radio counterparts to extreme X-ray young stellar objects 39 On the structure of stellar coronae 40 Microinstabilities and scattering of accelerated particles in plasmas 41 Dark matter in the Universe 42 X-ray properties of galaxy clusters 43 REM measurements versus standard models 44 II Who cares about weak geomagnetic storms? 45 Muon Spin Spectroscopy 47 Magnetism: Heavy Fermion Systems, Magnetic Ordering and Dynamics, Spin Glasses |j.SR studies of correlated electron ground states (I) 48 uSR studies of correlated electron ground states (II) 49 Heavy-fermion behaviour and stripe order in electron doped cuprates 50 Study of the magnetic properties of Ce3Pd20Si6 and Ce3Pd20Ge6 compounds 51 Moment collapse in UJ-a^S 52 Study of U- and RE-intermetallic compounds exhibiting quadrupolar and magnetic ordering phenomena: UPd3 53 Microscopic studies of the non-magnetic-magnetic transition in highly correlated electron systema 54 |iSR study of the non-fermi-liquid behaviour in U2Pt2ln 55 Study of the spin dynamics in axial magnets. 56 Spin behaviour in novel transition metal magnets 57 Internal fields in magnetically ordered Dy and Ho 58 Study of the dynamic and structure features of magnetism in holmium 59 Spin-fluctuations in YCo2 60 u+SR studies of the triangular lattice LiNiQ, 61 Magnetic behaviour of a two-leg organic spin-ladder compound 62 (iSR study on the S= V2 quantum spin system KCuCI3 63 Magnetic properties of the spinel ZnFe2O4 in crystalline and nanostructured modifications 64 Stripe order and spin dynamics in nickelates 65 Study of magnetism in novel hole-doped quasi-1 D cuprates 66 ^SR on (RC)2(NiB)2 67 Possible muonium formation in the erbium halides ErClj and Erl3 68 Condon domains in non-magnetic metals 69 Superconductivity Study of the magnetic properties of HoBajCUgO^ : 70 (x+SR on La2.x.yRExSryCu04 71 (J.SR investigation of the magnetic phase diagram of Bl, ^Sr, 85CaCu20e+5 72 Two stage melting transition of the vortex matter in BL.Srj.Ca.puO^j 73 Hole dynamics and localization in low-doped high-temperature superconductors 74 Local magnetic order in YBa^Cu 1.xCox)3O7 75 u.SR on "artificially aged" YBa,Cu3Oa6 76 u.SR investigation of the magnetic phase diagram of organic superconductora 77 jxSR studies of superconductivity and magnetism in organic molecular crystal systems 78 Systematic study of the magnetic penetration depth in Chevrel phase compounds 79 Semiconductors, Hydrogen in Metals Evidence for a novel muon species in crystalline silicon 80 Relaxation rate and paramagnetic frequency shift of negative-muon spin precession in silicon 81 Muons in sulphur 82 jxSR in II-VI solar cell materials 83 The JJ+ in metal-hydrogen (deuterium) systems 84 Chemistry: Radicals, Reaction Kinetics, Charge Transfer Reorientation dynamics and chemical reaction of cyclohexadienyl radicals in ZSM-5 zeolites 85 Heterogeneous processes of environmental free radicals 86 Radical chemistry without water - insights into cell membranes 87 Weak organic charge transfer systems 88 JJ.SR dynamics of liquid crystals studies by ALC 89 Temperature dependence of the hyperfine coupling constant of muonium in liquid H2O and D2O and in solid Si8O12-cages 90 Experiments with Low Energy Muons Range and range distribution of low energetic muons in matter 91 The use of slow muons for precision measurements of magnetic fields on a 10nm scale at a YBa2Cu307.s surface 92 Low energy p.SR study of the field distribution of a flux line lattice crossing a YBapu3O7.8 surface 93 Magnetism of thin chromium layers studied with low energy p+SR ......: 94 Slow muons to study CMR and spin-glass films 95 Experimental Techniques Low energy [i+ beam developments 96 Development of a novel time-differential jiSR data-acquisition system and its application to radio- frequency n-SR 97 Micro and Nano Technology 99 Replication of nanostructures with polymer injection molding 100 Nanoreplication in thin polymer films 101 Manufacture of moderator gratings for epithermal muons 102 Diffractive optical elements generated by e-beam lithography. 103 Nanostructured electrodes for electrochemical investigations 104 Nanostruotured surfaces for biomolecular immobilization 105 Thermogravimetric analysis of micro crystals: Experiment and finite element simulations 106 Highly efficient solar cells on low cost sheet ribbon grown silicon 107 Effects of spontaneous ordering on the elastic properties of GalnR, 108 High frequency optical rectification in bulkGaAs 109 Atomic structure of the carbon-induced c(4x4) reconstruction on Si(001) 110 TEM study of an anticorrelation in corrugated layers of Si,.8.yGexC/Si superlattices 111 Photoluminescence of C induced Ge quantum dots embedded in Si 112 Intersubband absorption in Si/SiGe MOW 113 Metal-insulator transition in a SiGe 2-dimensional hole gas 114 Amperometric immunosensing of penicillins 115 Functionalised glass chips for neuron cells 116 SPM for functional identification of individual biomolecules 117 One-dimensional confinement of molecules via selective adsorption 118 Radio- and Environmental Chemistry 119 Heavy Elements A 252Cf fission fragment source called Miss Piggy. 120 Miss Piggy, the new califomium-252 fission source as a generator of short-lived radionuclides 121 Thermochromatographic investigation of ruthenium with oxygen as carrier gas 122 169 174183ie4 Studies of gaschromatographic behaviour of ' Re jn the gas system He/O/HCI 123 Physicochemical characterization of seaborgium as oxide hydroxide 124 On-line chromatography of short-lived W isotopes with the multi-column technique 125 Production of 262Db in the reaction 248Crn(19F, 5n) 126 Fluoride complexation of rutherfordium (Rf, element 104) 127 Preliminary studies for the separation of263Rf in aqueous solution part I: Tracer experiments 128 Preliminary studies for the separation of263Rf in aqueous solution part II: On-line experiments 129 Thermochromatographic investigations of254Es bromides 130 HIVAPSI: A program to estimate cross-sections in heavy ion reactions 131 Calculation of cross sections in a-xn-reactions 132 CORA - 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