Pragmatic Transition Radiation Targets: BL4S 2025 Results from Team XTReme at ELSA

by Rasmus Partzsch (University of Bonn), Saime Gurbuz (uni-bonn)

Thursday 5 Feb 2026, 10:00 → 12:00 Europe/Berlin

Abstract: 

Beamline for Schools (BL4S) is an international outreach and research program that offers high-school students the opportunity to design and carry out a particle physics experiment at a major accelerator facility. In 2025, in addition to DESY and CERN, ELSA too opened its doors to students, inviting a winning team to carry out their experiment.

Team XTReme from Texas, USA, was one of the five winning teams of the competition and were invited to ELSA to perform their experiment. They proposed an experiment to study “Transition Radiation in Multi-Layered Dielectric–Metallic Targets for Soft X-Ray Generation and Beam Diagnostics”. The experiment focused on measuring transition radiation from multilayer dielectric–metallic targets, also including everyday, low-cost materials such as cling wrap, and space blanket foils. The setup combined an EUDET-type beam telescope for precise particle tracking with a TJ-Monopix2 for photon detection. TJ-Monopix2 is a depleted monolithic active pixel sensor (DMAPS). The successor chip OBELIX, is designed for the BELLE II vertex detector upgrade (VTX). Despite the simplicity of the target materials, transition radiation was successfully observed, demonstrating both the sensitivity of the setup and the feasibility of using inexpensive materials as TR targets in particle physics experiments.

In this talk, we present the preparation of various targets by the students, the experimental setup at ELSA, analysis procedures and results. Team XTReme’s measurements confirm that these accessible, low-cost materials can generate transition radiation, showing that with a little creativity, even cling wrap and space blankets can be deployed at particle physics detectors!

Join Zoom Meeting
https://uni-bonn.zoom-x.de/j/66253567797?pwd=R2MrNmNCQnl4K1hSejd6VnBEYXJ2QT09

Meeting ID: 662 5356 7797
Passcode: 599591