Successful cooling of a pixel tracker using gaseous helium: studies with a mock-up and a detector prototype

TL;DR

This paper demonstrates the successful cooling of a pixel detector using gaseous helium, validated through mock-up studies and a prototype, enabling low-mass, effective cooling for high heat density detectors in particle physics.

Contribution

It introduces a practical helium cooling method for pixel detectors, validated by mock-up and prototype tests, expanding cooling options for high-density heat applications.

Findings

Helium cooling effectively manages heat densities up to 400 mW/cm^2.

Mock-up and CFD simulations confirm the cooling approach.

Helium cooling reduces detector mass and minimizes multiple scattering effects.

Abstract

We report the successful operation of a functional pixel detector with gaseous helium cooling. Using an accurate mock-up beforehand, the cooling was validated. We use a miniature turbo compressor to propel the helium at $2\,g/s$ under ambient pressure conditions with gas temperatures above $0^{\circ}C$. Our earlier results based on computational fluid dynamics simulations and a much simpler mock-up are confirmed. With this, we paved the path to cool pixel detectors in experimental particle physics at heat densities up to $400\, mW/cm^2$ using helium. This enables cooling of detectors with very low mass requirements, minimising the effects of multiple Coulomb scattering effectively. The concept presented here is not limited to pixel detector applications and can be used to cool any surface with comparable heat-densities, only limited by shaping the helium gas flow.