Recent Studies of Hypernuclei Formation with Electron Beams at MAMI

• DOI: 10.1007/s00601-013-0777-z
• Publication Date: 2013-12-23T12:48:26Z
• Authors: Patrick Achenbach; Carlos Ayerbe Gayoso; Ralph Böhm; Olga Borodina; Damir Bosnar; Vakkas Bozkurt; Luka Debenjak; Michael O. Distler; Anselm Esser; Ivica Friščić; Yuu Fujii; Toshiyuki Gogami; Mar Gómez Rodríguez; Osamu Hashimoto; Satoshi Hirose; Hiroki Kanda; Masashi Kaneta; Eunhee Kim; Junichiro Kusaka; Amur Margaryan; Harald Merkel; Ulrich Müller; Sho Nagao; Satoshi N. Nakamura; Josef Pochodzalla; Christophe Rappold; Joerg Reinhold; Takehiko R. Saito; Alicia Sanchez Lo...; Salvador Sánchez ...; B. Sören Schlimme; Matthias Schoth; Florian Schulz; Concettina Sfienti; Simon Širca; Liguang Tang; Michaela Thiel; Kyo Tsukada
• Keywords: Hypernuclei; MAMI; KAOS; Mesonic weak decay; 0103 physical sciences; 01 natural sciences; 7. Clean energy

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.