Abstract
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 − momentum spectrum from which their masses can be extracted with a precision of 50 keV/c 2.
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Achenbach, P., Ayerbe Gayoso, C., Böhm, R. et al. Recent Studies of Hypernuclei Formation with Electron Beams at MAMI. Few-Body Syst 55, 887–892 (2014). https://doi.org/10.1007/s00601-013-0777-z
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DOI: https://doi.org/10.1007/s00601-013-0777-z