Experimental benchmark data for Monte Carlo simulated radiation effects of gold nanoparticles. Part I: Experiment and raw data analysis

TL;DR

This paper provides detailed experimental data on electron emission spectra from gold nanoparticles exposed to photons, serving as a reference for Monte Carlo radiation simulations, including raw data analysis and calibration procedures.

Contribution

It offers new benchmark data for gold nanoparticle electron emissions under photon interaction, aiding Monte Carlo simulation accuracy.

Findings

Measured electron spectra for gold nanoparticles at various photon energies.

Calibrated photon flux and spectrometer transmission for absolute spectral radiance.

Analyzed limitations of experimental data and raw data procedures.

Abstract

Electron emission spectra of gold nanoparticles (AuNPs) after photon interaction were measured over the energy range between 50 eV and 9500 eV to provide reference data for Monte Carlo radiation-transport simulations. Experiments were performed with the HAXPES spectrometer at the PETRA III high-brilliance beamline P22 at DESY (Hamburg, Germany) for photon energies below and above each of the gold L-edges, i.e., at 11.9 keV, 12.0 keV, 13.7 keV, 13.8 keV, 14.3 keV, and 14.4 keV. The study focused on a sample with gold nanoparticles with an average diameter of 11.0 nm on a thin carbon foil. Additional measurements were performed on a sample with 5.3 nm gold nanoparticles and on reference samples of gold and carbon foils. Further measurements were made to calibrate the photon flux monitor, to characterize the transmission function of the electron spectrometer and to determine the size of the photon beam. This allowed the determination of the absolute values of the spectral particle radiance of secondary electrons per incident photon flux. The paper presents the experimental and raw data analysis procedures, reviews the data obtained for the nanoparticle samples and discusses their limitations.