The response of Low Gain Avalanche Diodes (LGADs), a type of thin silicon detector with internal gain, to X-rays of energies between 6-16~keV was characterized at the Stanford Synchrotron Radiation Lightsource (SSRL). The utilized beamline at SSRL was 7-2, with a nominal beam size of 30~μm, repetition rate of 500~MHz, and with an energy dispersion ΔE/E of 10−4. Multi-channel LGADs, AC-LGADs, and TI-LGADs of different thicknesses and gain layer configurations from Hamamatsu Photonics (HPK) and Fondazione Bruno Kessler (FBK) were tested. The sensors were read out with a discrete component board and digitized with a fast oscilloscope or a CAEN fast digitizer. The devices' energy response, energy resolution, and time resolution were measured as a function of X-ray energy and position. The charge collection and multiplication mechanism were simulated using TCAD Sentaurus, and the results were compared with the collected data.
@article{arxiv.2504.18638,
title = {Synchrotron light source focused X-ray detection with LGADs, AC-LGADs and TI-LGADs},
author = {A. Molnar and Y. Zhao and S. M. Mazza and G. Oregan and M. Davis and S. Beringer and A. Tiernan and J. Ott and H. F. -W. Sadrozinski and A. Seiden and B. Schumm and F. McKinney-Martinez and A. Bisht and M. Centis-Vignali and G. Paternoster and M. Boscardin},
journal= {arXiv preprint arXiv:2504.18638},
year = {2025}
}