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作者单位:Patrick Achenbach (1) Carlos Ayerbe Gayoso (1) Ralph B?hm (1) Olga Borodina (2) Damir Bosnar (3) Vakkas Bozkurt (2) Luka Debenjak (4) Michael O. Distler (1) Anselm Esser (1) Ivica Fri??i? (3) Yuu Fujii (5) Toshiyuki Gogami (5) Mar Gómez Rodríguez (1) Osamu Hashimoto (5) Satoshi Hirose (5) Hiroki Kanda (5) Masashi Kaneta (5) Eunhee Kim (2) Junichiro Kusaka (5) Amur Margaryan (6) Harald Merkel (1) Ulrich Müller (1) Sho Nagao (5) Satoshi N. Nakamura (5) Josef Pochodzalla (1) Christophe Rappold (2) Joerg Reinhold (8) Takehiko R. Saito (2) Alicia Sanchez Lorente (7) Salvador Sánchez Majos (1) B. S?ren Schlimme (1) Matthias Schoth (1) Florian Schulz (1) Concettina Sfienti (1) Simon ?irca (4) Liguang Tang (9) Michaela Thiel (1) Kyo Tsukada (5)
1. Institut für Kernphysik, Johannes Gutenberg-Universit?t, 55099, Mainz, Germany 2. GSI Helmholtz Centre for Heavy Ion Research, 64291, Darmstadt, Germany 3. Department of Physics, University of Zagreb, 10002, Zagreb, Croatia 4. University of Ljubljana and Institut “Jo?ef Stefan- 1000, Ljubljana, Slovenia 5. Department of Physics, Tohoku University, Sendai, 980-8578, Japan 6. Yerevan Physics Institute, 375036, Yerevan, Armenia 8. Department of Physics, Florida International University, Miami, FL, 33174, USA 7. Helmholtz Institute Mainz, 55099, Mainz, Germany 9. Department of Physics, Hampton University, Hampton, VA, 23668, USA
ISSN:1432-5411
文摘
At the Mainz Microtron MAMI exploratory experiments on the spectroscopy of mesonic weak decays (MWD) of electroproduced Λ-hypernuclei were performed. A unique setup was realized to use the broad momentum-band kaon spectrometer Kaos at zero degree angle with respect to the high-intensity electron beam direction to tag strangeness producing processes. A sample of order 103 MWD from a beryllium target was collected by the coincidence technique with the high-resolution multi-spectrometer facility of the A1 Collaboration. It is conjectured that this sample contains monochromatic two-body decays from stopped hyperfragment decays as well as a wide momentum distribution of quasi-free produced Λ- and Σ-hyperon decays and three-body decays from hyperfragments. Stopped hyperfragments will be identified as monochromatic peaks in the π ?/sup> momentum spectrum from which their masses can be extracted with a precision of 50?keV/c 2.