The prospect of pileup induced backgrounds at the High Luminosity LHC (HL-LHC) has stimulated intense interest in developing technologies for charged particle detection with accurate timing at high rates. The required accuracy follows directly from the nominal interaction distribution within a bunch crossing (σ z ∼ 5 cm, σ t ∼ 170 ps). A time resolution of the order of 20-30 ps would lead to significant reduction of these backgrounds. With this goal, we present a new detection concept called PICOSEC, which is based on a "two-stage" Micromegas detector coupled to a Cherenkov radiator and equipped with a pho- * tocathode. First results obtained with this new detector yield a time resolution of 24 ps for 150 GeV muons, and 76 ps for single photoelectrons.

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In this investigation, we used the growth, photosynthetic physiological parameters, and targeted metabolite analysis to evaluate the responses of Eleutherococcus senticosus in different shading treatments. The results showed that the moderate shading treatment (Z1) promoted the growth and inhibited photosynthesis of plants. The severe shading treatment (Z2) inhibited both the growth and photosynthesis of the plants. Besides, Z1 had no significant effect on the PSII, while Z2 inhibited the PSII. Most of the eight medicinal metabolites accumulated in the Z1. The C6C1-and C6C3-type phenolics accumulated in the Z1, and the C6C3C6-type in the Z2. In conclusion, the moderate shading treatment accumulated more defensive phenolics; this might be the reason for this shading condition promoting the growth and the accumulation of medicinal metabolites of the plant. The result of this study laid a theoretical foundation for the further study of shading treatments on the secondary metabolism of Eleutherococcus senticosus.

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A: Detectors with a time resolution of a few tens of picoseconds and long-term durability in high particle fluxes are necessary for an accurate vertex separation in future particle physics experiments. The PICOSEC-Micromegas detector concept is a Micro-Pattern Gaseous Detector (MPGD) based solution addressing this particular challenge. It is based on a Micromegas detector coupled to a Cherenkov radiator and a photocathode. Primary electrons from the incident particles are generated in the photocathode and the time fluctuations due to different primary ionisation positions in the gaseous volume are reduced. The feasibility to reach a good time resolution using this concept was demonstrated in test beam studies, and time resolution values down to 24 ps were measured with muon beams at the CERN SPS accelerator complex. The previously simulated effects of different detector parameters on the time resolution were confirmed by measurements. For these measurements, a femtosecond laser system is used. For a single photoelectron, a time resolution of better than 50 ps is achieved mostly by minimising the drift gap distance. Furthermore, gain and Amplitude-to-Signal ratio (A/Q) with different gas mixtures are compared. K: Micropattern gaseous detectors (MSGC, GEM, THGEM, RETHGEM, MHSP, MI-CROPIC, MICROMEGAS, InGrid, etc); Particle tracking detectors (Gaseous detectors); Photon detectors for UV, visible and IR photons (gas) (gas-photocathodes, solid-photocathodes); Timing detectors