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Zhou, Bing

Publications and source records attributed to Zhou, Bing.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Studies of Cherenkov photon production in PbF 2 crystals using proton beams at Fermilab

Future lepton colliders such as the FCC-ee, CEPC, ILC, or a muon collider will collect large data samples that allow precision physics studies with unprecedented accuracy, especially when the data is collected by innovative state-of-the-art detectors. An electromagnetic calorimeter based on scintillating crystals, designed to separately record Cherenkov and scintillation light, can achieve precision measurements of electrons and photons without sacrificing jet energy resolution, given adequate light collection efficiency and separation. This paper presents initial measurements from a program aimed at developing such a calorimeter system for future colliders. Finally, we focus on using PbF 2 crystals to enhance the understanding of Cherenkov light collection, marking the first step in this endeavor.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2023

High rate studies of the ATLAS sTGC detector and optimization of the filter circuit on the input of the front-end amplifier

Abstract The Large Hadron Collider (LHC) at CERN is expected to be upgraded to the High-Luminosity LHC (HL-LHC) by 2029 and achieve instantaneous luminosity around 5–7.5 × 10 34 cm -2 s -1 . This represents a more than 3–4 fold increase in the instantaneous luminosity compared to what has been achieved in Run 2. The New Small Wheel (NSW) upgrade is designed to be able to operate efficiently in this high background rate environment. In this article, we summarize multiple performance studies of the small-strip Thin Gap Chamber (sTGC) at high rate using nearly final front-end electronics. We demonstrate that the efficiency versus rate distribution can be well described by an exponential decay with electronics dead-time being the primary cause of loss of efficiency at high rate. We then demonstrate several methods that can decrease the electronics dead-time and therefore minimize efficiency loss. One such method is to install either a pi-network input filter or pull-up resistor to minimize the charge input into the amplifier. We optimized the pi-network capacitance and pull-up resistor resistance using the results from our measurements. The results shown here were not only critical to finalizing the components on the front-end board, but also are critical for setting the optimal operating parameters of the sTGC detector and electronics in the ATLAS cavern.

Instruments & Instrumentation↗
DOE OSTI2022

Development and test of a mini-Data Acquisition system for the High-Luminosity LHC upgrade of the ATLAS Monitored Drift Tube detector

New front-end electronics including ASICs and FPGA boards are under development for the ATLAS Monitored Drift Tube (MDT) detector to handle the large data rates and harsh environment expected at high-luminosity LHC runs. A mobile Data Acquisition (miniDAQ) system is designed to perform integration tests of these front-end electronics. In addition, it will be used for surface commissioning of 96 small-radius MDT (sMDT) chambers and for integration and commissioning of new front-end electronics on the present ATLAS MDT chambers. Details of the miniDAQ hardware and firmware are described in this article. Here, the miniDAQ system is also used to read out new front-end electronics on an sMDT prototype chamber using cosmic muons and results obtained are shown.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2022

A signal packet router for the upgrade of the Muon spectrometer at the ATLAS experiment

Here, we present the design, characterization, and production of a signal packet router for the upgrade of the ATLAS forward muon detector. The router serves as a packet switch in one of the primary trigger paths. It handles up to 12 serial inputs at 4.8 Gbps/input from on-detector electronics and outputs four 4.8 Gbps to the trigger processing circuits. In the 12-to-4 packet switching process, the input streams are decoded and synchronized to a common clock domain for data packets forwarding and NULL packets suppression. Challenges in the design include operations of multi-giga hertz serial links with low and constant latency (<100 ns) for packet routing, as well as mitigation of radiation-induced effects in the harsh radiation environment over 10 years of detector operation. The Router design has been fully characterized and demonstrated to meet all specifications. In total 256 Routers were installed in the detector. Its design concept can be used in other similar applications, particularly in a radiation environment.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2020

Design of a Time-to-Digital Converter ASIC and a mini-DAQ system for the Phase-2 upgrade of the ATLAS Monitored Drift Tube detector

We present the second prototype of a time-to-digital (TDC) ASIC for the upgrade of the ATLAS Monitored Drift Tube (MDT) detector for High-Luminosity LHC operations. Compared to the first prototype, triple modular redundancy has been implemented for the configuration and flow control logic. Here, the total power consumption is increased by less than 10 mW while achieving the same time resolution and channel uniformity. A mini-DAQ system has been built to verify the front-end electronics chain with the new prototype together with other ASICs and boards in triggered mode. Cosmic ray tests with a small-diameter MDT chamber indicate that the configuration and data transmission of the readout electronics perform well. It is expected that this prototype design will be used in the final production.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Design and performance of a TDC ASIC for the upgrade of the ATLAS Monitored Drift Tube detector

We present the prototype of a time-to-digital (TDC) ASIC for the upgrade of the ATLAS Monitored Drift Tube (MDT) detector for high-luminosity LHC operation. This ASIC is based on a previously submitted demonstrator ASIC designed for timing performance evaluation, and includes all features necessary for the various operation modes, as well as the migration to the TSMC 130 nm CMOS technology. Here, we present the TDC design with the emphasis on added features and performance optimization. Tests of the timing performance demonstrate that this ASIC meets the design specifications. The TDC has a bin size of about 780 ps, and a timing bin variations within ±40 ps for all 24 channels with leading and trailing edge digitization, while the power consumption has been limited to 250 mW, corresponding to a consumption of about 5.2 mW per edge measurement.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

A multi-layer SEU mitigation strategy to improve FPGA design robustness for the ATLAS muon spectrometer upgrade

We present a multi-layer single-event upset mitigation strategy implemented in a low-cost Xilinx Artix-7 FPGA. The implementation is targeted for a trigger data router for the ATLAS muon spectrometer upgrade. The mitigation strategy employs three layers of protection to improve overall FPGA design robustness: use of triple-modular redundancy for FPGA fabric logic and embedded soft-error mitigation in the first layer; further enhancement with multi-boot FPGA reconfiguration across multiple copies of configuration memory in the second layer; and FPGA power cycling and configuration memory re-initialization in the third layer. Here, the effectiveness of this scheme has been evaluated at two different neutron facilities, LANSCE and NCSR ‘‘Demokritos’’, with 800 MeV and 25 MeV beam energies, respectively. Testing was performed with a similar configuration to that planned for final operation. We discuss the testing strategy and summarize the test results to estimate the expected data loss over 10 years of operation in the ATLAS experiment.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Mass production of a trigger data serializer ASIC for the upgrade of the muon spectrometer at the ATLAS experiment

The Trigger Data Serializer (TDS) is a custom ASIC designed for the upgrade of the innermost station of the endcap ATLAS Muon spectrometer. Here, it is a mixed-signal chip with two working modes that can handle up to 128 detector channels. A total of 6000 TDS ASICs have been produced for detector operation. This paper discusses a custom automatic test platform we developed to provide quality control of the TDS ASICs. We introduce the design, illustrate the test procedures, and discuss the experimental results.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Field-free Magnetization Switching by Utilizing the Spin Hall Effect and Interlayer Exchange Coupling of Iridium

Magnetization switching by spin-orbit torque (SOT) via spin Hall effect represents as a competitive alternative to that by spin-transfer torque (STT) used for magnetoresistive random access memory (MRAM), as it doesn’t require high-density current to go through the tunnel junction. For perpendicular MRAM, however, SOT driven switching of the free layer requires an external in-plane field, which poses limitation for viability in practical applications. Here we demonstrate field-free magnetization switching of a perpendicular magnet by utilizing an Iridium (Ir) layer. The Ir layer not only provides SOTs via spin Hall effect, but also induce interlayer exchange coupling with an in-plane magnetic layer that eliminates the need for the external field. Such dual functions of the Ir layer allows future build-up of magnetoresistive stacks for memory and logic applications. Experimental observations show that the SOT driven field-free magnetization reversal is characterized as domain nucleation and expansion. Micromagnetic modeling is carried out to provide in-depth understanding of the perpendicular magnetization reversal process in the presence of an in-plane exchange coupling field.

Science & Technology - Other Topics↗
DOE OSTI2018

Discovery of QCA570 as an Exceptionally Potent and Efficacious Proteolysis Targeting Chimera (PROTAC) Degrader of the Bromodomain and Extra-Terminal (BET) Proteins Capable of Inducing Complete and Durable Tumor Regression

Proteins of the bromodomain and extra-terminal (BET) family are epigenetics “readers” and promising therapeutic targets for cancer and other human diseases. We describe herein a structure-guided design of [1,4]oxazepines as a new class of BET inhibitors and our subsequent design, synthesis, and evaluation of proteolysis-targeting chimeric (PROTAC) small-molecule BET degraders. Our efforts have led to the discovery of extremely potent BET degraders, exemplified by QCA570, which effectively induces degradation of BET proteins and inhibits cell growth in human acute leukemia cell lines even at low picomolar concentrations. We report QCA570 achieves complete and durable tumor regression in leukemia xenograft models in mice at well-tolerated dose-schedules. QCA570 is the most potent and efficacious BET degrader reported to date.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Structure-Based Discovery of CF53 as a Potent and Orally Bioavailable Bromodomain and Extra-Terminal (BET) Bromodomain Inhibitor

We report the structure-based discovery of CF53 (28) as a highly potent and orally active inhibitor of bromodomain and extra-terminal (BET) proteins. By the incorporation of a NH-pyrazole group into the 9H-pyrimido[4,5-b]indole core, we identified a series of compounds that bind to BRD4 BD1 protein with K i values of <1 nM and achieve low nanomolar potencies in the cell growth inhibition of leukemia and breast cancer cells. The most-promising compound, CF53, possesses excellent oral pharmacokinetic properties and achieves significant antitumor activity in both triple-negative breast cancer and acute leukemia xenograft models in mice. Determination of the co-crystal structure of CF53 with the BRD4 BD1 protein provides a structural basis for its high binding affinity to BET proteins. CF53 is very selective over non-BET bromodomain-containing proteins. Furthermore, these data establish CF53 as a potent, selective, and orally active BET inhibitor, which warrants further evaluation for advanced preclinical development.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Experimental Investigation and Finite Element Analysis on Fatigue Behavior of Aluminum Alloy 7050 Single-Lap Joints

The fatigue behavior of single-lap four-riveted aluminum alloy 7050 joints was investigated by using high-frequency fatigue test and scanning electron microscope (SEM). Stress distributions obtained by finite element (FE) analysis help explain the fatigue performance. The fatigue test results showed that the fatigue lives of the joints depend on cold expansion and applied cyclic loads. FE analysis and fractography indicated that the improved fatigue lives can be attributed to the reduction in maximum stress and evolution of fatigue damage at the critical location. The beneficial effects of strengthening techniques result in tearing ridges or lamellar structure on fracture surface, decrease in fatigue striations spacing, delay of fatigue crack initiation, crack deflection in fatigue crack propagation and plasticity-induced crack closure.

36 MATERIALS SCIENCE↗
DOE OSTI2018

High-Affinity Peptidomimetic Inhibitors of the DCN1-UBC12 Protein–Protein Interaction

Cullin-RING ligases (CRLs) regulate the turnover of approximately 20% of the proteins in mammalian cells and are emerging therapeutic targets in human diseases. The activation of CRLs requires the neddylation of their cullin subunit, which is controlled by an activation complex consisting of Cullin-RBX1-UBC12-NEDD8-DCN1. In this paper, we describe the design, synthesis, and evaluation of peptidomimetics targeting the DCN1-UBC12 protein–protein interaction. Starting from a 12-residue UBC12 peptide, we have successfully obtained a series of peptidomimetic compounds that bind to DCN1 protein with KD values of <10 nM. Determination of a cocrystal structure of a potent peptidomimetic inhibitor complexed with DCN1 provides the structural basis for their high-affinity interaction. Cellular investigation of one potent DCN1 inhibitor, compound 36 (DI-404), reveals that it effectively and selectively inhibits the neddylation of cullin 3 over other cullin members. Further optimization of DI-404 may yield a new class of therapeutics for the treatment of human diseases in which cullin 3 CRL plays a key role.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Long non-coding RNA-422 acts as a tumor suppressor in colorectal cancer

Highlights: • LncRNA-422 in CRC tissues was significantly lower than that in adjacent tissues. • The expression of lncRNA-422 was correlated with TNM stage of CRC. • LncRNA-422 inhibits the proliferation, migration and invasion of CRC cells. • LncRNA-422 acts as a tumor suppressor by PI3K/AKT/mTOR pathway in CRC. Colorectal cancer (CRC) is one of the most frequent cancer in numerous of countries worldwidely. The initiation and progression of CRC is an extremely complex process, and have been suggested a correlation with Long non-coding RNAs (lncRNAs). Our results showed that lncRNA-422(ENST00000415820) significantly downregulated in the tissues and serum of CRC patients, and is closely associated with the poor prognosis. Then gain or loss of lncRNA-422 models in SW480 and SW620cells were established. The results showed that lncRNA-422 overexpression inhibited cell proliferation, migration, and invasion. Knockdown of lncRNA-422 promoted tumorigensis. Western blot and qRT-PCR were performed to examine the activity of the PI3K/AKT/mTOR pathway in CRC cells after alternation of lncRNA-422. Results showed that lncRNA-422 acts as a tumor suppressor by PI3K/AKT/mTOR pathway in CRC.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

A programmable time alignment scheme for detector signals from the upgraded muon spectrometer at the ATLAS experiment

We present a programmable time alignment scheme used in an ASIC for the ATLAS forward muon trigger development. The scheme utilizes regenerated clocks with programmable phases to compensate for the timing offsets introduced by different detector trace lengths. Each ASIC used in the design has 104 input channels with delay compensation circuitry providing steps of ~ 3 ns and a full range of 25 ns for each channel. Detailed implementation of the scheme including majority logic to suppress single-event effects is presented. The scheme is flexible and fully synthesizable. Here, the approach is adaptable to other applications with similar phase shifting requirements. In addition, the design is resource efficient and is suitable for cost-effective digital implementation with a large number of channels.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗