Parts | Days | Selection | Search | Updates | Downloads | Help

AKBP: Arbeitskreis Beschleunigerphysik

AKBP 17: Instrumentation III

AKBP 17.2: Talk

Thursday, March 23, 2023, 17:45–18:00, CHE/0183

Acoustic Measurement of the Energy Deposition of Heavy Ions in Water at 4°C — •Anna-Katharina Schmidt, Julia Liese, Alexander Praßelsperger, Felix Balling, Sonja Gerlach, Martin Speicher, Walter Assmann, and Jörg Schreiber — LMU München, Fakultät für Physik - Medizinische Physik, Am Coulombwall 1, 85748 Garching

Energy deposition of ions in water leads to the emission of a pressure, i.e. ionoacoustic wave. It is commonly described in the thermoacoustic approximation, that is, localized heating and volume change is considered as prime cause of the wave. If this was true, no pressure wave is expected at 4°C, which was indeed observed after localized absorption of light. Contrary, when initiated by protons, this minimum is shifted to significantly higher temperatures of around 4.5°C, hinting towards an additional, non-thermal excitation mechanism that has not yet been understood and is referred to as "charge effect" in the literature [1]. We want to investigate this effect, which as of today lacks an explanation, experimentally for femto-second laser induced water plasmas and heavy ions with higher charge than protons for the first time by measuring the polarity change of the pressure wave around the water anomaly at 4°C. Understanding the non-thermal effects has potential implications for completely new measurement principles, could open up new insights into the fast, pre-thermal processes and even help classifying the relevance of mechanically induced radiation damage.This work is supported by GSI-LMU F&E cooperation LMSCH2025.

[1] R. Lahmann et al. Astroparticle Physics 65 (2015): 69-79.