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The University of Torino (UniTO) and the National Institute for Nuclear Physics (INFN-TO) are investigating the use of Ultra Fast Silicon Detectors (UFSD) for beam monitoring in radiobiological experiments with therapeutic proton beams. The single particle identification approach of solid state detectors aims at increasing the sensitivity and reducing the response time of the conventional monitoring devices, based on gas detectors. Two prototype systems are being developed to count the number of beam particles and to measure the beam energy with time-of-flight (ToF) techniques. The clinically driven precision (< 1%) in the number of particles delivered and the uncertainty < 1 mm in the depth of penetration (range) in radiobiological experiments (up to 108 protons/s fluxes) are the goals to be pursued. The future translation into clinics would allow the implementation of faster and more accurate treatment modalities, nowadays prevented by the limits of state-of-the-art beam monitors. The experimental results performed with clinical proton beams at CNAO (Centro Nazionale di Adroterapia Oncologica, Pavia) and CPT (Centro di Protonterapia, Trento) showed a counting inefficiency 2, and a deviation of few hundreds of keV of measured beam energies with respect to nominal ones. The progresses of the project are reported.

The Compact Muon Solenoid (CMS) detector at the CERN Large Hadron Collider (LHC) is undergoing an extensive Phase II upgrade program to prepare for the challenging conditions of the High-Luminosity LHC (HL-LHC). In particular, precision timing can offset the performance degradation due to event pileup at the HL-LHC, recovering the purity of vertices of current LHC conditions. As such, a new timing layer will be introduced to measure minimum ionizing particles (MIPs) with a time resolution of 30 ps. The endcap region of this MIP Timing Detector (MTD) will be instrumented with a hermetic double layer of silicon low gain avalanche detectors (LGADs), covering the high radiation pseudo-rapidity region between |η|=1.6 to 3.0. Radiation tolerance studies of the LGADs indicate excellent performances adequate to cope with the Endcap Timing Layer (ETL) requirements. The LGADs have intrinsic gain, which enhances the MIP signal and provides adequate signal-to-noise for good timing precision. We present the status of the art for the LGADs for the endcap region of the MTD and report on recent beam test results.

Low Gain Avalanche Detectors (LGAD) are silicon sensors with a time resolution better than 20 ps. The ATLAS and CMS experiments are designing LGAD detectors to address the pile-up challenge at the High Luminosity-Large Hadron Collider (HL-LHC) . The Institute of High Energy Physics (IHEP) High-Granularity Timing Detector group has recently developed its first version of LGAD sensors. The LGAD structure was designed using Technology Computer-Aided Design (TCAD) simulations and optimized to obtain a high breakdown voltage and ideal gain. The n-type Junction Termination Extension (N-JTE) zone is a critical structure to guarantee a high breakdown voltage. The gain layer is optimized for an ideal gain factor and hence good time resolution. The optimized LGAD sensor has a gain higher than six and a breakdown voltage higher than 400 V.

This article was written to explain the suitability between the scores of advance learning activities achieved by students with the "gain score" from the results of the pre-test and post-test of HOTS questions. Advance learning activities include, 1)analyzing, 2)communicating/dialogue, 3)discussing/collaborating. Whereas HOTS question is a question that testing students’ creativity and strategy in solving problems and is at the level of C4 (analyzing), C5 (evaluating) and C6 (Creating). EXO OLO TASK Learning Model was applied in this quasi-experimental research for four meetings in class X IS 1. The model was practiced by a model teacher and learning activity data was collected by six observers. The suitability was obtained by percentage analysis and strengthened by correlation test with the help of SPSS version 20. The results showed that, 1) during learning, all students showed consistent basic learning activities; 2) most students had a "gain score" in the medium category. While 24.13% of students were able to reach high categories and only 6.89% of students with low gain scores, 3) 65.51% of students had scores of learning activities that match the "gain score" and 34, 48% did not. The implementation of this model has only been applied in one class and one school so that it is necessary to implement it in broader classes and schools.

There are many methods based on linac for THz radiation production. As one of the options for the Beijing Advanced Light, an ERL test facility is proposed for THz radiation. In this test facility, there are 4 kinds of methods to produce THz radiation: coherent synchrotron radiation (CSR), synchrotron radiation (SR), low gain FEL oscillator, and high gain SASE FEL. In this paper, we study the characteristics of the 4 kinds of THz light sources.

A method is proposed for determining the gain of gas mixtures. The results are interpreted taking into account the influence of a transverse inhomogeneity of the active medium. It is shown theoretically how the refractive index and gain inhomogeneities influence differently the modes, the eigenfrequencies, and the losses of a stable resonator with circular spherical mirrors. An equation is obtained for describing the dynamics of the complex radiation field amplitude.

This paper presents the design of an ultralow power receiver front-end designed for a wireless sensor network (WSN) in a 0.18 μm CMOS process. The author designs two front-ends working in the saturation region and the subthreshold region respectively. The front-ends contain a two-stage cross-coupling cascaded common-gate (CG) LNA and a quadrature Gilbert IQ mixer. The measured conversion gain is variable with high gain at 24 dB and low gain at 7 dB for the saturation one, and high gain at 22 dB and low gain at 5 dB for the subthreshold one. The noise figure (NF) at high gain mode is 5.1 dB and 6.3 dB for each. The input 1 dB compression point (IP1dB) at low gain mode is about −6 dBm and −3 dBm for each. The front-ends consume about 2.1 mA current from 1.8 V power supply for the saturation one and 1.3 mA current for the subthreshold one. The measured results show that, comparing with the power consumption saving, it is worth making sacrifices on the performance for using the subthreshold technology.

The ATLAS Tile Calorimeter digitizer system samples photomultiplier signals from the scintillating tiles of the hadronic calorimeter. For each channel a pair of 10-bit ADCs digitize high and low gain signals at 40.08 MHz to provide the necessary 16-bit dynamic range. The sampled data is temporarily stored in digital pipelines for up to 6.375 \mu­s, awaiting a level-1 accept. For each accept received, the corresponding sampled pulse is transferred to a derandomizer buffer for subsequent readout to the data acquisition system (DAQ). The main functionality of the digitizer is implemented in radiation tolerant ASICs, using a fault tolerant architecture to minimize the consequences of radiation induced faults.

The example of one-wave emission from a ring gas laser with a linear phase anisotropy of its resonator is used to demonstrate the possibility of lasing characterized by undamped fluctuations of both the intensity and the polarization parameters of waves generated in weakly anisotropic resonators. Such spontaneous fluctuations appear because of instability of the polarization parameters of the output waves obtained from an active medium which could have a low gain.