Annual Report 2010 Technische Universität München Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) www.frm2.tum.de Content Directors’ Report Directors’ Directors’ Report 3 The crystal structure of complex ruthenates: Combining X-ray and neutron diffraction 75 Directors’ Report: Progress through change 6 Cu-ion active species in ZSM5 zeolites: Heterogeneity and site morphologies 77 The year in pictures 7 In-situ probing of fast defect annealing in Ni with a high-intensity positron beam 79 Porosity and structure of a TiO2-ceramic composite determined by TOF-GISANS 81 Proteins & Large Scale Structures 83 Instruments & Methods 13 Membranes for rapid stem cell adhesion characterized by neutron and X-ray reflectometry 83 Instrumental improvements 15 Sticky boundary layer and anisotropic diffusion in nanochannels 85 Decay rate measurement of the negative positronium ion 19 Self-assembling in solution of crystalline-amorphous olefin block-copolymers 87 3 & Methods SEOP polarized He for polarization analysis at the JCNS 21 Confined polymer dynamics on clay platelets 89 Instruments Visualization of water uptake in a trunk 23 Near-surface structure of a microemulsion 91 Optimising the neutron diffractometer STRESS-SPEC for surface strain scanning 25 Solvent distribution in block copolymer thin films 93 Direct observation of the surface segregation of Cu in Pd 27 Detection of lithium traces in organic samples 29 Reactor & Industry 95 Improving components and techniques 31 The operation of the neutron source in 2010 97 Progress in the development of a 49.9 % enriched UMo dispersion fuel for the FRM II 99 Scientific Highlights 35 Medical Applications 101 Magnetism & Superconductivity 37 Percutaneous medical radiation treatments 101 Asymmetric spin-excitation spectra in Fe-pnictides 37 Automated preparation of a 188Re-compound for skin cancer therapy 103 Normal-state hourglass dispersion in spin excitations of FeSexTe1-x 39 New magnetic excitation elucidates the pseudo-gap mystery in a model high-Tc superconductor 41 Facts & Figures 105 Scientific Highlights The microscopic spin dynamics in the normal and superconducting state of UBe13 43 Events: Schools, workshops, conferences, political visits and industrial expert meeting 107 11 Single magnetic chirality in the magnetoelectric NdFe3( BO3)4 45 Always by the users’ side! 111 Spin transfer torques in MnSi at ultra-low current densities 47 Attracting pupils and journalists: Public relations and visitors’ service 113 Critical fluctuations in Mn1-xFexSi studied at RESEDA 49 Publications 115 Neutron depolarisation imaging of the Kondo system CePd1-xRhx 51 Committees 141 Larmor diffraction in the ferromagnetic superconductor UGe2 53 Staff 147 Microscopic picture of magnetic correlation with swift heavy ion irradiation 55 Partner institutions 153 Microscopic origin of training in an exchange bias system 57 Imprint 155 Material Science 59 Probing ab-/desorption of deuterium in hydrogen storage materials with neutron diffraction 59 Reactor & Industry Divacancies and the hydrogenation of Mg-Ti films with short range chemical order 61 Free volume and swelling in thin hydrogel films 63 Crystal structure and Li motion of Li8SeN2 and Li8TeN2 65 Structural changes and refinement of cubicα -Li2TiO3 upon heating to high temperatures 67 Residual stress fields after heat treatment in cladded steel of process vessels 69 Neutron scattering, a tool in development of new CoRe-based alloys for high-T applications 71 Phase transition studies of LaAlO3 by high-resolution neutron Larmor diffraction 73 Facts & Figures Directors’ Report 1 The new meteo tower of the Technische Universität München, measuring weather data for the FRM II. Directors’ Report: Progress through change In hindsight, the year 2010 will surely rank as a in SR9a was removed to allow for a new beam Directors’ Report Directors’ major milestone in the fledgling history of the port for PoliHeidi, the single crystal neutron dif- th FRM II. On December 17 , the Technische Uni- fractometer using hot polarized neutrons. In this 5 / 6 versität München and the Helmholtz Centres in way, it will become an independent instrument Jülich, Geesthacht and Berlin signed a contract in the future. A major upgrade involved the ad- confirming their collaboration and the promotion dition of 400 detector tubes for the time-of-flight of the scientific use of the FRM II. At this time, instrument TOFTOF. Under commission and an agreement was also reached between the Ba- ready for the first friendly users are our single varian State Ministry of Science, Research and diffractometer for large structures BIODIFF (joint Arts and the Federal Ministry of Education and project of TUM and JCNS) and the high inten- Research (BMBF) on the financial contribution sity reflectometer MARIA of the JCNS. From the of the Federal Republic to the scientific explora- perspective of the expectant first users, great tion of the FRM II to the tune of 198 Mio€ over strides were made in the commissioning of the the following ten years. Together with the annual huge SANS-1 machine (HZG and TUM). budget of 25 Mio€ from Bavaria and 10.5 Mio€ from the HGF centres, this will allow us to fur- Looking towards the future, new large projects ther improve the service and optimise use of the will appear as the DFG funded PERC instrument German neutron source. for particle physics at the instrument MEPHISTO, and a large number of instrumentation projects Late 2010 saw the beginning of our first long funded by the BMBF within the context of Col- maintenance period in order to exchange the laborative Research (Verbundforschung), having beam tube (SR) 11 and, thus, rebuild the posi- a three year budget for instruments at the FRM II, tron source. The cadmium inside the beam nose totalling 10.2 Mio€. The ultra cold neutron source had burned up and had to be replaced. On this with projected instruments to investigate the occasion, an elongated thimble was installed in neutron life time and the electric dipole-moment, the heavy water moderator tank in order to ac- respectively, progresses well. Besides these fas- commodate the future irradiation facility for 99Mo cinating topics on site, the FRM II is looking even production: A small but important step to pre- further, across the borders to the new European pare the FRM II for the production of this medical Spallation Source in Scandinavia, ESS. In May isotope which is in such high demand. In addi- 2010, the FRM II signed a Memorandum of Un- tion, a comprehensive number of maintenance derstanding with the ESS to collaborate in the procedures were undertaken by the reactor de- area of scientific, educational and industrial ap- partment under the guidance of our new techni- plications. Together with our colleagues from the cal director, Dr. Anton Kastenmüller. Helmholtz Centres we will, over the next three years, contribute to the design update phase of In parallel, the science division dismantled en- the ESS funded mainly by the BMBF. tirely the radiography and tomography station ANTARES which will move from beam port SR4b to SR4a in order to free the SR4b port for the particle physics instrument MEPHISTO, which will become the first instrument operational in the new neutron guide hall east. The beam dump Klaus Seebach Winfried Petry Anton Kastenmüller The year in pictures November 22 Works to exchange the beam tube SR11 of nd the positron source NEPOMUC have started. The experimental tube is being removed. April 30th Directors’ Report The new laboratory in the industrial applica- tions centre of the FRM II is inaugurated. It 7 / 8 is dedicated to the preparation of samples and offers the analysis of organic colloidal samples. March 16 Chun Loong of theth Tsinghua University in Peking presents the compact pulsed hadron source to members of the FRM II. th July 25 A dozen students decided to tour the neutron source on the „Schülertag“ at the Technische Universität München. They were interested in studying physics. September 3 September 11th The Consul General ofrd the United States in The mayor of Garching, Hannelore Gabor Munich, Conrad R. Tribble (4 (m.), meets the Technical Director of the visits the neutron source. He is accompa FRM II, Anton Kastenmüller (r.). She intro nied by members of the company General th from the right), duces her new office manager Hans-Martin- Electric. The directorate of the FRM II guides Weichbrodt. the group. - April 13 April 8th th At the VDI expert meeting, 60 participants FRM II Scientific Director, Winfried Petry is in from business and academia discussed me terviewed by the German broadcasting com - thods for non-destructive testing of industrial pany 3sat. The focus is on nuclear energy. - components. th May 15 - Visitor of the German Church Congress in front of a poster for the FRM II Long Night of Science announcing that the tours are fully booked. More than 400 visitors got the chance to take a look a the interior of the neutron source. th May 15 Children of FRM II staff members were allowed to meet the reactor drivers on the occasion of the Long Night of Science. They could enter the switch room, gaze into the reactor pool and look at the instruments in the neutron guide hall west. The year in pictures June 29 th A Canadian delegation of physicians and businessmen interested in the production of radioisotopes at the FRM II, visits the neutron source guided by Administrative Director, nd July 22 Klaus Seebach (l.) and deputy Scientific Directors’ Report Director, Jürgen Neuhaus (4 The FRM II sends its own running team to the be2run, a corporate challenge in Munich. The 9 / 10 twelve members ran 6.4 km. Stefan Söll- th from right). radl (back row, left), the fastest of the team, November 11 became 20th of a total of 20,000 participants in 21 min. 55 sec. The old storage building of the company th Kraftanlagen München at the FRM II area is taken down to make way for a new storage depot to be built in 2011.