Fluorescence Efficiency and Visible Re-emission Spectrum of Tetraphenyl Butadiene Films at Extreme Ultraviolet Wavelengths

TL;DR

This study measures the fluorescence efficiency and visible re-emission spectrum of TPB films when illuminated with EUV light, providing essential data for neutrino and dark matter detection experiments.

Contribution

It offers new measurements of TPB's re-emission spectrum and fluorescence efficiency across relevant EUV wavelengths, aiding detector design.

Findings

Re-emission spectrum characterized at multiple EUV wavelengths

Fluorescence efficiency measured from 120 to 250 nm

Data supports optimized use of TPB in scintillation detection

Abstract

A large number of current and future experiments in neutrino and dark matter detection use the scintillation light from noble elements as a mechanism for measuring energy deposition. The scintillation light from these elements is produced in the extreme ultraviolet (EUV) range, from 60 - 200 nm. Currently, the most practical technique for observing light at these wavelengths is to surround the scintillation volume with a thin film of Tetraphenyl Butadiene (TPB) to act as a fluor. The TPB film absorbs EUV photons and reemits visible photons, detectable with a variety of commercial photosensors. Here we present a measurement of the re-emission spectrum of TPB films when illuminated with 128, 160, 175, and 250 nm light. We also measure the fluorescence efficiency as a function of incident wavelength from 120 to 250 nm.