[en] The JUNO (Jiangmen Underground Neutrino Observatory) experiment is a multi-purpose neutrino experiment designed to determine the neutrino mass hierarchy and precisely measure oscillation parameters. It will be composed of a 20k ton liquid scintillator (LS) central detector equipped with about 18000 20-inch photon-multipliers (PMTs) and 25000 3-inch PMTs, a water Cherenkov detector with about 2000 20-inch PMTs, and a top tracker. Monte-Carlo simulation is a fundamental tool for optimizing the detector design, tuning reconstruction algorithms, and performing physics study. The status of JUNO simulation software will be presented, including generator interface, detector geometry, physics processes, MC truth, pull-mode electronic simulation.

[en] With the development of computing, 64-bit systems are taking place of 32-bit systems, which is both a challenge and opportunity for the BESIII offline software. Updating BESIII offline software to 64-bit systems will improve software performance significantly. But on the other hand BESIII offline software is so large and complicated, and comparing to 32-bit systems, there are significantly changes in many aspects in 64-bit systems, such as data modules, CPU computing model, which make upgrading hard and complicated. In the article, we will describe the procedure of the upgrading, explain the key problems met, and analyze final physics results and performance.(authors)

[en] Monte Carlo method is used to simulate the random noise in the BES II drift chamber and its effect on the performance. noises from both t and q channels are considered on hit and non-hit sense wires respectively. Track efficiency and momentum resolution under different noise levels and different noise distributions are presented

[en] Using experimental data, Monte Carlo tuning is implemented for performance parameters associated with the scintillation counters and readout electronics of the BESⅢ time-of-flight (TOF) system, as part of the full simulation model. The implementation of the tuning is described for simulations designed to reproduce the performance of a number of TOF system parameters, including pulse height, hit efficiency, time resolution, dead channels and background. In addition, comparisons with experimental data are presented. (authors)

[en] The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose neutrino experiment. It consists of a central detector, a water pool and a tracker placed on top. The central detector, which is used for neutrino detection, consists of a 20 kt liquid scintillator target and about 18,000 20-inch photomultiplier tubes (PMTs) to detect scintillation photons. Simulation software is an important part of the JUNO offline software. To speed up the simulation, a parallelized simulation framework has been developed based on the SNiPER framework and Geant4 version 10. The SNiPER task components are in charge of the event loop, which can run in sequential mode, Intel TBB mode and other modes. Based on SNiPER, the simulation framework and its underlying parallel libraries have been decoupled. However, parallelized simulation of correlated events is a challenge. In order to keep the correct event order, a component called global buffer is developed in SNiPER. In this paper, an overview of the parallelized JUNO simulation framework is presented. The global buffer is used in the parallelized event correlation simulation. An event generator produces events with timestamps in sequential mode. These events are put into the global buffer and processed by the detector simulation algorithms in different tasks. After simulation, the events are saved into ROOT files with a ROOT I/O service running in a dedicated thread. Finally, the software performance is presented.

[en] The Beijing Spectrometer III (BESIII) is a general-purpose detector at Beijing Electron Positron Collider II (BEPCII) for the experimental τ-charm physics study. It mainly studies the offline processing of BESIII raw data. Firstly, it introduces the implementation of raw data access by using the raw data conversion service. Then it describes optimizations of the service to improve input/output performance and to meet the requirements of Monte Carlo simulation. Finally, it presents how to reuse the service in the BESIII online system and the solution of raw data filtering. (authors)

[en] The Jiangmen Underground Neutrino Observatory (JUNO) detector is designed to determine the neutrino mass hierarchy and precisely measure oscillation parameters. The general purpose design also allows measurements of neutrinos from many terrestrial and non-terrestrial sources. The JUNO Event Data Model (EDM) plays a central role in the offline software system. It describes the event data entities through all processing stages for both simulated and collected data, and provides persistency via the input/output system. Also, the EDM is designed to enable flexible event handling such as event navigation, as well as the splitting of MC IBD signals and mixing of MC backgrounds. This paper describes the design, implementation and performance of the JUNO EDM. (authors)

[en] SNiPER is a general purpose offline software framework for high energy physics experiment. It provides some features that are attractive to neutrino experiments, such as the event buffer. More than one events are available in the buffer according to a customizable time window, so that it is easy for users to apply events correlation analysis. We also implemented the MT-SNiPER to support multithreading computing based on Intel TBB. In MT-SNiPER, the event loop is split into pieces, and each piece is dispatched to a task. The global buffer, an extension and enhancement to the event buffer, is implemented for MT-SNiPER. The global buffer is available by all threads. It keeps all the events being processed in memory. When there is an available task, a subset of its events is dispatched to that task. There can be overlaps between the subsets in different tasks due to the time window. However, it is ensured that each event is processed only once. In the task side, the subsets of events are locally managed by a normal event buffer. So the global buffer can be transparent to most user algorithms. Within the global buffer, the multithreading computing of MT-SNiPER becomes more practicable.

[en] This paper describes the construction of MDC III, such as the design of framework, construction process, wire tension measurement, high voltage leakage current measurement of the wire and the cosmic ray test. With these careful tests, we conclude that MDC III has reached its design goals

[en] In the JUNO experiment, a geometry management system has been developed in offline software. The system is based on Geometry Description Markup Language (GDML) to provide consistent detector description for different applications, such as simulation, reconstruction, visualization and analysis. It works for different detector designs with flexibility and has been successfully used for detector optimization and performance evaluation with Monte Carlo data.