High precision mass measurements of hypernuclei - achievements and perspectives
A. Essera, S. Nagaoe, F. Schulza, P. Achenbacha, C. Ayerbe Gayosoa, R. Bohma, O. Borodinaa,b, D. Bosnarc, A. Botvinag, V. Bozkurtb, L. Debenjakd , M.O. Distlera, I. Friscicc, Y. Fujiie, T. Gogamie, M. Gomez Rodrigueza, O. Hashimotoe∗, S. Hirosee, H. Kandae, M. Kanetae, E. Kimb, Y. Kohla, J. Kusakae, A. Margaryan f , H. Merkela, M. Mihovilovicd , U. Mullera, S.N. Nakamurae, J. Pochodzalla†a,g, C. Rappoldb, J. Reinholdh, T.R. Saitoa,b,g, A. Sanchez Lorenteg, S. Sanchez Majosa, B.S. Schlimmea, M. Schotha, C. Sfientia, S. Sircad , L. Tangi, M. Thiela, K. Tsukadae, A. Webera, K. Yoshidab
Kaon Tagging at 0° Scattering Angle for High-Resolution Decay-Pion Spectroscopy
At the Mainz Microtron hypernuclei can be studied by (e,e'K) reactions. By detecting the kaon which is emitted in forward direction, with the KAOS spectrometer placed at 0 scattering angle, reactions involving open strangeness production are tagged. High-resolution magnetic spectrometers are then used to coincidentally detect the mono- energetic decay-pions from mesonic two-body weak decays of light hypernuclei at rest. As a pioneering experiment has confirmed, the KAOS spectrometer is exposed to a large flux of background particles, mostly positrons from bremsstrahlung pair production. In order to increase the e ciency of kaon identification the KAOS spectrometer was modi- fied to suppress…