The KLOE electromagnetic calorimeter Passeri, A.; Adinolfi, M.; Ambrosino, F. ...
Nuclear physics. Section B, Proceedings supplement,
08/1999, Letnik:
78, Številka:
1
Journal Article
The KLOE lead-scintillating fiber calorimeter has been fully installed in the KLOE assembly hall, and is currently operated with the final electronics and data acquisition system, using a cosmic rays ...trigger. The technical solutions adopted for the detector construction, the front end electronics design, and the data acquisition system are reviewed. The calibration procedure with cosmic rays is also presented. The performances obtained and the detector stability are shown to have met the tight requirements of the KLOE experiment in terms of time and energy resolution.
The reaction 7Li(pi+,pi-)7B has been measured at incident pion energies of 30-90 MeV. 7Li constitutes the lightest target nucleus, where the pionic charge exchange may proceed as a binary reaction to ...a discrete final state. Like in the Delta-resonance region the observed cross sections are much smaller than expected from the systematics found for heavier nuclei. In analogy to the neutron halo case of 11Li this cross section suppression is interpreted as evidence for a proton halo in the particle-unstable nucleus 7B.
Phys.Lett.B363:41-45,1995 The KARMEN collaboration has reported the possible observation of a hitherto
unknown neutral and weakly interacting particle x, which is produced in the
decay pi -> mu + x ...with a mass m(x) = 33.9 MeV. We have searched for this
hypothetical decay branch by studying muons from pion decay in flight with the
LEPS spectrometer at the piE3 channel at PSI and find branching ratios BR(pi-
to mu- anti-x) < 4e-7 and BR(pi+ to mu+ x) < 7e-8 (95\% C.L.). Together with
the limit BR > 2e-8 derived in a recent theoretical paper our result would
leave only a narrow region for the existence of x if it is a heavy neutrino.
The KARMEN collaboration has reported the possible observation of a hitherto unknown neutral and weakly interacting particle x, which is produced in the decay pi -> mu + x with a mass m(x) = 33.9 ...MeV. We have searched for this hypothetical decay branch by studying muons from pion decay in flight with the LEPS spectrometer at the piE3 channel at PSI and find branching ratios BR(pi- to mu- anti-x) < 4e-7 and BR(pi+ to mu+ x) < 7e-8 (95\% C.L.). Together with the limit BR > 2e-8 derived in a recent theoretical paper our result would leave only a narrow region for the existence of x if it is a heavy neutrino.
