Pressure-dependent decay of the 2p⁵-3p configuration in neon excited by alpha particles

Abstract

The pressure dependence of the decay of the Ne (2p53p) states excited by an energetic pulsed alpha -particle beam is studied in the pressure range 70-1500 mbar. The 2p53p states are populated either promptly, within a few ns, or by subsequent collisional transfer within the 2p53p states. The decay rates of all the 2p53p states above 300 mbar are linear with the pressure and unaffected by trapping from the 2p53p states as these are depopulated by excimer formation. Below 300 mbar the decay rates are reduced by trapping. No quadratic pressure dependence due to excimer formation is found; the upper limit for the formation rate is estimated as (6*10-7 (ns mbar2)-1. Estimated values for the rates of collisional transfer within and out of the 2p53p configuration are given.

Classification of Simple Graded Lie Algebras With Nonsemisimple Component $ L_0$

“…This window was centred about 15 mm from the entrance aperture [3]. The experimental set-up, including pulse electronics, was described in [4].…”

“…For spectral studies in the UV and visible regions and for time-resolved recordings of the 3p 5 4p-configuration a monochromator was used [4]. For spectral recordings of the visible and NIR region (380-1050 nm) a Multichannel Echelle Spectrograph (MES 5000) was used [5].…”

“…The output from the PMT recorded the particle bunches of the beam arriving at the rate of the cyclotron frequency (12 MHz for protons and 9.52 MHz for alpha particles). These PMT pulses were then used as timing pulses in the pulse electronics [4], consisting of a pre-amplifier, a constant fraction timing discriminator (CFTD) and a time-to-amplitude converter (TAC). For higher target pressures the space between the foils had to be evacuated in order not to attenuate the beam.…”

“…Microchannel plates (MCPs) were incorporated into the existing particle beam collimating system. The electrons scattered from the first stainless steel foil (see figure 1 in [4]) were collected on the MCPs by a positive bias voltage. Thus, the output from the MCPs recorded the particle bunches of the beam arriving at the rate of the cyclotron frequency.…”

Test Beam Data Analysis and Simulation of a RICH Prototype for the NA62 Experiment

“…The Neon scintillation detection is slightly shaped by the reflectivity of the vessel; its parameters are tuned considering the fact that in the data there is no information about its wavelength. In literature several emission spectra can be found [11], also within the range of visible, compatible with quantum efficiency of the PMs, but the only constraint from data is the time constant, which has been tuned to 3 ns to fit the data.…”