Study of charging-up of PCB planes for neutrino experiment readout

TL;DR

This paper investigates the charging-up effects on PCB planes used in liquid argon TPCs for neutrino detection, demonstrating how charge accumulation influences electron trajectories and proposing a new anode configuration.

Contribution

It introduces a novel PCB-based anode design for liquid argon TPCs and provides experimental evidence of charge focusing effects on electron drift.

Findings

Charge accumulation affects electron trajectories in PCB anodes.

The new anode design shows promising charge readout capabilities.

Experimental results confirm focusing effects due to insulator surface charges.

Abstract

The use of double-faced, metallized, perforated PCB planes, segmented into strips for the anodic read-out of ionization signals in liquid argon TPCs, is emerging as a promising technology for charge readout in liquid argon TPCs used in large volume detectors.As a proof of concept, a prototype liquid Argon TPC hosting this new anode configuration based on single side perforated PCB planes has been constructed and exposed to cosmic rays at LNL in Italy. Tests were performed with both the metallized and insulating sides of the anode facing the drift volume, providing the first evidence of the focusing effect on drift electron trajectories through the PCB holes due to charge accumulation on the insulator surface.