First demonstration of 3D optical readout of a TPC using a single photon sensitive Timepix3 based camera

TL;DR

This paper demonstrates a novel 3D optical readout method for liquid Argon TPCs using a single-photon sensitive Timepix3 camera, enabling detailed event reconstruction with potential scalability and cost benefits.

Contribution

It introduces the first 3D optical readout of a TPC using a Timepix3-based camera combined with an image intensifier, showcasing proof of concept with cosmic rays and alpha sources.

Findings

Successful 3D imaging of cosmic rays and alpha particles in CF4 gas

Effective use of Timepix3 camera for precise hit localization

Potential for scalable and cost-effective TPC readout methods

Abstract

The ARIADNE project is developing innovative optical readout technologies for two-phase liquid Argon time projection chambers (LArTPCs). Optical readout presents an exciting alternative to the current paradigm of charge readout. Optical readout is simple, scalable and cost effective. This paper presents first demonstration of 3D optical readout of TPC, using CF4 gas as a proof of principle. Both cosmic rays and an Americium-241 alpha source have been imaged in 100 mbar CF4. A single-photon sensitive camera was developed by combining a Timepix3 (TPX3) based camera with an image intensifier. When a pixel of TPX3 is hit, a packet containing all information about the hit is produced. This packet contains the x,y coordinates of the pixel, time of arrival (ToA) and time over threshold (ToT) information. The z position of the hit in the TPC is determined by combining drift velocity with ToA information. 3D event reconstruction is performed by combining the pixels x,y location with this calculated z position. Calorimetry is performed using time over threshold, a measure of the intensity of the hit.