Measurement of the photon structure function at ALEPH

TL;DR

This paper reports measurements of the photon structure function F2gamma at LEP energies, using advanced unfolding techniques to improve accuracy across various Q^2 values.

Contribution

It introduces a two-dimensional unfolding method based on maximum entropy, enhancing the precision of F2gamma measurements at high energies.

Findings

Measured F2gamma at multiple Q^2 values.

Implemented maximum entropy unfolding to reduce errors.

Provided data consistent with theoretical predictions.

Abstract

The photon structure function F2gamma has been measured with data taken by the ALEPH collaboration at LEP centre-of-mass energies sqrt s = 91 GeV with < Q^2 > of 9.9, 20.7 and 284 GeV^2 and sqrt s = 183 GeV with < Q^2 > of 13.7 and 56.5 GeV^2. For the data at sqrt s = 183 GeV a two-dimensional unfolding method employing the principle of maximum entropy is used, which reduces the errors compared to one-dimensional methods.