Proposal of the Readout Electronics for the WCDA in LHAASO Experiment

TL;DR

This paper presents the design and prototype testing of specialized readout electronics for the WCDA in the LHAASO experiment, enabling precise time and charge measurements across a large detector array.

Contribution

It introduces a novel electronics architecture with multiple gain readout, hybrid data transmission, and precise clock synchronization for large-scale water Cherenkov detectors.

Findings

Prototype modules are under laboratory testing.

Electronics achieve high precision in time and charge measurement.

Techniques support large dynamic range from single P.E. to 4000 P.E.

Abstract

The LHAASO (Large High Altitude Air Shower Observatory) experiment is proposed for very high energy gamma ray source survey, in which the WCDA (Water Cherenkov Detector Array) is the one of the major components. In the WCDA, a total of 3600 PMTs are placed under water in four ponds, each with a size of 150 m x 150 m. Precise time and charge measurement is required for the PMT signals, over a large signal amplitude range from single P.E. (photo electron) to 4000 P.E. To fulfill the high requirement of signal measurement in so many front end nodes scattered in a large area, special techniques are developed, such as multiple gain readout, hybrid transmission of clocks, commands, and data, precise clock phase alignment, and new trigger electronics. We present the readout electronics architecture for the WCDA and several prototype modules, which are now under test in the laboratory.