0000000000303863
AUTHOR
J. Schuler
Optimization of the JUNO liquid scintillator composition using a Daya Bay antineutrino detector
To maximize the light yield of the liquid scintillator (LS) for the Jiangmen Underground Neutrino Observatory (JUNO), a 20 t LS sample was produced in a pilot plant at Daya Bay. The optical properties of the new LS in various compositions were studied by replacing the gadolinium-loaded LS in one antineutrino detector. The concentrations of the fluor, PPO, and the wavelength shifter, bis-MSB, were increased in 12 steps from 0.5 g/L and <0.01 mg/L to 4 g/L and 13 mg/L, respectively. The numbers of total detected photoelectrons suggest that, with the optically purified solvent, the bis-MSB concentration does not need to be more than 4 mg/L. To bridge the one order of magnitude in the detect…
2.45 GHz synchronised polarised electron injection at MAMI
Abstract A semiconductor modelocked diode laser has been used to produce picosecond spin-polarised electron bunches from strained GaAsP photocathodes and inject them into MAMI, synchronised to the 2.45 GHz accelerating field. The laser meets the operational requirements of MAMI producing stable electron beams, with a polarisation purity of 72% and a transmission efficiency of 52% at an accelerated beam current of 10.1 μA.
<title>Spin-polarized electron kinetics under high-intensity picosecond excitation</title>
ABSTRACT Spin-polarized electron kinetics is studied by time-resolved polarized photoemission with picosecond resolution. The re-sponse time of strained layer photocathodes is found to be in a range of a few picosecond offering an ultrafast response andhigh spin-polarization of emitted electrons. The studies of the sub-picosecond spin dynamics are facilitated in high-intensityexcitation regime when the length of the emission pulse is enlarged due to the dispersion of acceleration time and Coulombrepulsion ofthe electrons in their flight in the vacuum.Keywords: optical orientation, spin kinetics, strained semiconductor layer, time-resolved emission. 1. INTRODUCTION GaAs, layers are known to …