A novel method for the absolute fluorescence yield measurement by AIRFLY

TL;DR

This paper presents a new technique for measuring the absolute fluorescence yield of air induced by electrons, reducing systematic uncertainties by comparing fluorescence to Cerenkov emission, with preliminary results from multiple facilities.

Contribution

A novel method using Cerenkov emission as a reference to measure fluorescence yield with reduced calibration uncertainties.

Findings

Preliminary measurements at Frascati with 350 MeV electrons.

Application of the technique at lower energies at Argonne with 14 MeV electrons.

Potential for improved precision in fluorescence yield measurements.

Abstract

One of the goals of the AIRFLY (AIR FLuorescence Yield) experiment is to measure the absolute fluorescence yield induced by electrons in air to better than 10% precision. We introduce a new technique for measurement of the absolute fluorescence yield of the 337 nm line that has the advantage of reducing the systematic uncertainty due to the detector calibration. The principle is to compare the measured fluorescence yield to a well known process - the Cerenkov emission. Preliminary measurements taken in the BFT (Beam Test Facility) in Frascati, Italy with 350 MeV electrons are presented. Beam tests in the Argonne Wakefield Accelerator at the Argonne National Laboratory, USA with 14 MeV electrons have also shown that this technique can be applied at lower energies.