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Breitenfurt bei Wien, Austria

Mariazzi S.,Stefan Meyer Institute For Subatomare Physik | Di Noto L.,University of Trento | Di Noto L.,University of Genoa | Nebbia G.,National Institute of Nuclear Physics, Italy | Brusa R.S.,University of Trento
Journal of Physics: Conference Series | Year: 2015

In recent experiments on positronium time of flight (Ps-TOF) we have studied emission of cooled and thermalized Ps into vacuum from oxidized nanochannels synthetized in silicon. Ps cools down through collisions with the walls of the channels before exiting into vacuum. An important unknown parameter in the Ps-TOF measurements is the permanence time in the medium, i.e. the Ps cooling time before emission into vacuum. In this paper we describe an experiment that allows us to estimate the cooling time of Ps by analyzing the Ps-TOF spectra of cool Ps at three different distances from the sample. © Published under licence by IOP Publishing Ltd. Source


Tanaka Y.K.,University of Tokyo | Friedrich S.,Justus Liebig University | Fujioka H.,Kyoto University | Geissel H.,Helmholtz Center for Heavy Ion Research | And 14 more authors.
Few-Body Systems | Year: 2013

We are going to perform an inclusive spectroscopy experiment of η′ mesic nuclei with the 12C(p,d) reaction to study in-medium properties of the η′ meson. In nuclear medium, the η′ meson mass may be reduced due to partial restoration of chiral symmetry. In case of sufficiently large mass reduction and small absorption width of η′ at normal nuclear density, peak structures of η′ mesic states in 11C will be observed near the η′ emission threshold even in an inclusive spectrum. The experiment will be carried out at GSI with proton beam supplied by SIS using FRS as a spectrometer. The detail of the experiment is described. © 2013 Springer-Verlag Wien. Source


Poli Lener M.,National Institute of Nuclear Physics, Italy | Corradi G.,National Institute of Nuclear Physics, Italy | Curceneau C.,National Institute of Nuclear Physics, Italy | Romero Vidal A.,National Institute of Nuclear Physics, Italy | And 3 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

Time projection chamber (TPC) has been successfully used as a central tracker and a particle identification device in a number of a high-energy physics experiments. However, the performance requirements on TPC for new high-rate particle experiments greatly exceed the abilities of traditional TPC readout by multi-wire proportional chamber (MWPC). Gas Electron Multiplier (GEM) detector has great potential to improve TPC performances when used as amplification device. In this paper we present the R&D activity on a new GEM-based TPC (TPG) detector for the inner part of the AMADEUS experiment, a new experimental proposal at DAΦNE accelerator at LNF, aiming to perform measurements of the low-energy negative kaons interactions in nuclei. In order to evaluate the TPG feasibility, a 10 × 10 cm2 prototype with a drift length up to 15 cm are designed. The performances of a 10 × 10cm2 pre-existing prototype with a reduced drift gap, operated with Ar/CO2/CF4 (45/15/40) gas mixture and successfully tested at BTF facility, are presented. The gas mixture properties, such as the electron drift velocity and the diffusion, have been measured and they result comparable with those simulated with Garfield. A good resolution along the beam direction (z-coordinate), sufficient for a more large scale TPG in AMADEUS, is achieved. © 2009 Elsevier B.V. All rights reserved. Source


Faber M.,Vienna University of Technology | Faifman M.P.,RAS Research Center Kurchatov Institute | Ivanov A.N.,Vienna University of Technology | Marton J.,Stefan Meyer Institute For Subatomare Physik | And 4 more authors.
Physical Review C - Nuclear Physics | Year: 2011

We calculate the energy-level displacement of the excited np state of kaonic deuterium in terms of the p-wave scattering length of K -d scattering. We solve the Faddeev equations for the amplitude of K -d scattering in the fixed-center approximation and derive the complex p-wave scattering length of K -d scattering in terms of the s-wave and p-wave scattering lengths of KN scattering. The estimated uncertainty of the complex p-wave scattering length is of about 15%. For the calculated width Γ 2p=10.203 meV of the excited 2p state of kaonic deuterium we evaluate the yield YK -d=0.27% of x rays for the K α emission line of kaonic deuterium. Using the complex s-wave and p-wave scattering lengths of KN scattering, calculated in B. Borasoy, R. Nißler, and W. Weise and W. Weise and R. Härtle, we get the width Γ 2p=2.675meV of the excited 2p state and the yield YK -d=1.90% of x rays for the K α emission line of kaonic deuterium. The results obtained in this paper can be used for planning experiments on the measurements of the energy-level displacement of the ground state of kaonic deuterium, caused by strong low-energy interactions. © 2011 American Physical Society. Source


Itahashi K.,Accelerator Centre | Fujioka H.,Kyoto University | Geissel H.,Helmholtz Center for Heavy Ion Research | Hayano R.S.,University of Tokyo | And 13 more authors.
Progress of Theoretical Physics | Year: 2012

A novel method is proposed to measure η'(958) meson bound states in 11C nuclei by missing mass spectroscopy of the 12C(p, d) reaction near the η' production threshold. It is shown that peak structures will be observed experimentally in an inclusive measurement in case that the in-medium η' mass reduction is sufficiently large and that the decay width of η' mesic states is narrow enough. Such a measurement will be feasible with the intense proton beam supplied by the SIS synchrotron at GSI combined with the good energy resolution of the fragment separator FRS. Copyright © Progress of Theoretical Physics 2012 All rights reserved. Source

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