Hongkui Lv

Timing calibration of the LHAASO-KM2A electromagnetic particle detectors

The Large High Altitude Air Shower Observatory (LHAASO) is a multipurpose project focusing on high energy gamma ray astronomy and cosmic ray physics. The 1 km2 array (KM2A) of this observatory will consist of 5242 electromagnetic particle detectors (EDs) and 1171 muon detectors (MDs). The remoteness and numerous EDs extremely demand a robust and automatic calibration procedure. In this paper, a self-calibration method which relies on the measurement of charged particles within the extensive air showers is proposed. The method is fully validated by Monte Carlo simulation and successfully applied in a KM2A prototype array experiment. The self-calibration method can be used to determine the detector time-offset constants at the subnanosecond level, which is adequate to meet the physical requirements of LHAASO experiment.

Calibration and monitoring of LHAASO-KM2A muon detectors with muon decay events

The Large High Altitude Air Shower Observatory (LHAASO) will be constructed at 4400 m asl in Daocheng, Sichuan Province, with the aim of discovering sources of ultra-high energy cosmic rays and studying cosmic ray physics. The whole array includes 1171 muon detectors (MDs), constituting the largest muon detector array in the world. The special high altitude and wide-field environment requires simple and stable calibration as well as monitoring method of MDs. In this paper, the muon decay events will be selected for calibrating the charge and monitoring the water level of each MD. In the prototype muon detector, the simulation and experiment results reveal that the charge of the decay electron is approximately 0.147 times that of the vertical equivalent muon for a standard MD, and the QVEM/Qe shows a linear correlation with the water level.

Long-term stability plastic scintillation for LHAASO-KM2A

In order to study the long-term stability of plastic scintillaotr for LHAASO-KM2A, thermal aging tests of materials (BC-408, ND-100, HND-S2) were made. A forecast of tile operational time was made for normal conditions of usage (20% redution of light output). The plastic scintillator operational time can be estimated and its lifetime is determined from an Arrhenius plot.

Timing Calibration of the LHAASO-KM2A Electromagnetic Particle Detectors Using Charged Particles Within the Extensive Air Showers

The Large High Altitude Air Shower Observatory (LHAASO) is a new generation extensive air shower (EAS) experiment focusing on high energy gamma ray astronomy and cosmic ray physics. In the LHAASO, 5242 electromagnetic particle detectors (EDs) and 1171 muon detectors (MDs), which cover an area of 1.3 km\(^{2}\), are designed to measure the number density and arrival time of EAS secondary particles. The remoteness and numerous detectors extremely demand a robust, automatic calibration method. In this work, a self-calibration method which uses charged particles within the EASs as the calibration beam is developed. The method is implemented in the Monte Carlo simulation and initially applied in a prototype array experiment, from which the precision and efficiency are estimated.