41 research outputs found
Selective Field-Ionization Electron Detector at Low Temperature of 10 mK Range (NUCLEAR SCIENCE RESEARCH FACILITY?Particle and Photon Beams)
Combined with a dilution refrigerator, selective field-ionization detection system with a channel electron multiplier optimized at 10 mK-range temperature was developed. The detection efficiency of the ionized electrons from the n~110 Rydberg states of Rb is 98% at the lowest achieved temperature of 12 mK
Different mechanism of two-proton emission from proton-rich nuclei Al and Mg
Two-proton relative momentum () and opening angle ()
distributions from the three-body decay of two excited proton-rich nuclei,
namely Al p + p + Na and Mg p
+ p + Ne, have been measured with the projectile fragment separator
(RIPS) at the RIKEN RI Beam Factory. An evident peak at MeV/c as
well as a peak in around 30 are seen in the two-proton
break-up channel from a highly-excited Mg. In contrast, such peaks are
absent for the Al case. It is concluded that the two-proton emission
mechanism of excited Mg is quite different from the Al case, with
the former having a favorable diproton emission component at a highly excited
state and the latter dominated by the sequential decay process
Coherent Time Evolution of Highly Excited Rydberg States in Pulsed Electric Field: Opening a New Scheme for Stringently Selective Field Ionization (NUCLEAR SCIENCE RESEARCH FACILITY-Beams and Fundamental Reaction)
Coherent time evolution of highly excited Rydberg states in Rb (98 n 150) under pulsed electric field in high slew rate regime was investigated with the field ionization detection. We observed for the first time a discrete transition of the threshold ionization field with slew rate, the behavior of which depends also on the position of the low l states relative to the adjacent manifold. The experimental results strongly suggest that the coherent interference effect plays decisive role for such transitional behavior, and bring us a new, quite effective scheme for the stringently selective field ionization