Development of Radiation Hard N+-on-P Silicon Microstrip Sensors for Super LHC

Radiation tolerance up to 1015 1-MeV neq/cm2 is required for the silicon microstrip sensors to be operated at the Super LHC experiment. As a candidate for such sensors, we are investigating non-inverting n+-on-p sensors. We manufactured sample sensors of 1 times 1 cm in 4" and 6" processes with implementing different interstrip electrical isolation structures. Industrial high resistive p-type wafers from FZ and MCZ growth are tested. They are different in crystal orientations lang100rang and lang111rang with different wafer resistivities. The sensors were irradiated with 70-MeV protons and characterized in views of the leakage current increase, noise figures, electrical strip isolation, full depletion voltage evolution, and charge collection efficiency

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

Performance Estimation of the Belle II Aerogel RICH Counter in the First Beam Collision

International audienceThe Belle II experiment at the SuperKEKB facility started the beam collision in 2018, aiming search for the New Physics beyond the Standard Model. The Aerogel Ring Imaging Cherenkov (ARICH) counter is a particle identification (PID) device in the forward endcap of the Belle II detector to provide 4$\sigma$ separation of charged kaons and pions of momenta up to 3.5 GeV. The ARICH counter is a proximity-focusing RICH counter to identify particle species based on the angular distribution of Cherenkov photons located in 30 cm depth of narrow space and 1.5 T of high magnetic field. Two layers of the silica aerogel with different refractive indices emits photons as Cherenkov ring image. A total of 420 of Hybrid Avalanche Photo Detectors (HAPDs) are used to measure the 2-dimensional distribution of photons. We have collected ring images in the first beam collision data during the Phase II commissioning run and studies for the PID performance estimation are being carried out toward the Phase III physics data taking starting in 2019

Performance and commissioning of HAPDs in the Aerogel RICH counter

International audienceThe Belle II Aerogel Ring Imaging Cherenkov (ARICH) counter uses the angular distribution of Cherenkov photons emitted in silica aerogel to discriminate between charged pions and kaons. The Hybrid Avalanche Photo Detector (HAPD) is used as the photo-sensor, and is clearly the most critical component of the detector. HAPDs were installed into ARICH in July 2017, and ARICH was installed in the Belle II spectrometer in the end of 2017. During the Belle II beam commissioning in spring 2018, the performance of HAPDs was evaluated through measurements of the offset value, noise level and pulse height. Long term stability of the signal-to-noise ratio and the fraction of dead channel was also monitored. The signal-to-noise ratio exceeded 6, and the fraction of dead channels was less than 1%. The results of the performance evaluation and of the commissioning showed that the ARICH counter fulfills the requirements

Performance Evaluation of the HAPD in the Belle II Aerogel RICH Counter

International audienceThe Hybrid Avalanche Photo Detector (HAPD) is used as a photon detector for Aerogel Ring Imaging Cherenkov counter (ARICH), a particle identification device at Belle II. ARICH measures Cherenkov angles of photons emitted in silica aerogel radiators, hence a high photon detection efficiency is required by the HAPD module, a combination of HAPD and front-end electronics board. We evaluate the performance of the HAPD modules by measuring the noise level, the offset value, the pulse height, temperature dependency and the variation of performance in the beam commissioning period. This article describes the results of performance evaluation of the HAPD and shows that it fulfills the requirements of ARICH

Performance of the Belle II Silicon Vertex Detector

The Belle II experiment at the SuperKEKB collider of KEK (Japan) will accumulate 50 ab−1 of e+e− collision data at an unprecedented instantaneous luminosity of 8 ×1035 cm−2s−1, about 40 times larger than its predecessor. The Belle II vertex detector plays a crucial role in the rich Belle II physics program, especially for time-dependent measurements. It consists of two layers of DEPFET-based pixels and four layers of double sided silicon strips detectors(SVD). The vertex detector has been recently completed and installed in Belle II for the physics run started in spring 2019. We report here results on the commissioning of the SVD and its performance measured with the first collision data set

A Study of the Radiation Tolerance of CVD Diamond to 70 MeV Protons, Fast Neutrons and 200 MeV Pions

We measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 μm pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than 0.1 MeV), and a third group of samples with 200 MeV pions, in steps, to (8.8±0.9) × 1015 protons/cm2, (1.43±0.14) × 1016 neutrons/cm2, and (6.5±1.4) × 1014 pions/cm2, respectively. By observing the charge induced due to the separation of electron–hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all datasets can be described by a first-order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons, and 200 MeV pions. We find the damage constant for diamond irradiated with 70 MeV protons to be 1.62±0.07(stat)±0.16(syst)× 10−18 cm2/(pμm), the damage constant for diamond irradiated with fast reactor neutrons to be 2.65±0.13(stat)±0.18(syst)× 10−18 cm2/(nμm), and the damage constant for diamond irradiated with 200 MeV pions to be 2.0±0.2(stat)±0.5(syst)× 10−18 cm2/(πμm). The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond. We find 70 MeV protons are 2.60 ± 0.29 times more damaging than 24 GeV protons, fast reactor neutrons are 4.3 ± 0.4 times more damaging than 24 GeV protons, and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons. We also observe the measured data can be described by a universal damage curve for all proton, neutron, and pion irradiations we performed of Chemical Vapor Deposition diamond. Finally, we confirm the spatial uniformity of the collected charge increases with fluence for polycrystalline Chemical Vapor Deposition diamond, and this effect can also be described by a universal curveWe measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 μm pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than 0.1 MeV), and a third group of samples with 200 MeV pions, in steps, to (8.8±0.9) × 1015 protons/cm2, (1.43±0.14) × 1016 neutrons/cm2, and (6.5±1.4) × 1014 pions/cm2, respectively. By observing the charge induced due to the separation of electron–hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all datasets can be described by a first-order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons, and 200 MeV pions. We find the damage constant for diamond irradiated with 70 MeV protons to be 1.62±0.07(stat)±0.16(syst)× 10−18 cm2/(p μm), the damage constant for diamond irradiated with fast reactor neutrons to be 2.65±0.13(stat)±0.18(syst)× 10−18 cm2/(n μm), and the damage constant for diamond irradiated with 200 MeV pions to be 2.0±0.2(stat)±0.5(syst)× 10−18 cm2/(π μm). The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond. We find 70 MeV protons are 2.60 ± 0.29 times more damaging than 24 GeV protons, fast reactor neutrons are 4.3 ± 0.4 times more damaging than 24 GeV protons, and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons. We also observe the measured data can be described by a universal damage curve for all proton, neutron, and pion irradiations we performed of Chemical Vapor Deposition diamond. Finally, we confirm the spatial uniformity of the collected charge increases with fluence for polycrystalline Chemical Vapor Deposition diamond, and this effect can also be described by a universal curve