Exploring high-dose-rate electron irradiation for radiobiology using a 10 PW laser source

Advancements in high-power laser technology have opened new possibilities for electron acceleration, enabling the development of novel irradiation platforms for radiobiology studies. Ultrahigh dose rate (UHDR) radiation delivery is emerging as a promising approach for cancer therapy. The FLASH effect, observed under UHDR irradiation, has demonstrated the ability to preserve antitumor efficacy while reducing damage to healthy tissues. High-intensity petawatt laser systems (such as the one available at ELI-NP) offer a potential solution, capable of generating very high-energy electrons (VHEEs) at extreme dose rates greater than to 1012 Gy/s in ultra-short pulses ( 1 ps). This paper reports for the first time the design, implementation, and characterization of a setup dedicated to the irradiation of live cells (healthy and cancerous) using electrons produced by the interaction of a 10 PW laser with a mixed gas jet target (N2 + He). The experimental setup was optimized to ensure precise evaluation of electron beam parameters like energy distribution, dose rate, and spatial uniformity, making it suitable for controlled biological experiments. Dosimetry was performed using radiochromic films (RCF), ionization chambers (IC), and Optically Stimulated Luminescence detectors (OSL), ensuring accurate dose delivery to cell cultures. To validate the system, in vitro assays were conducted to assess cell viability post-irradiation, confirming the feasibility of using such an electron source for radiobiological studies. This work provides a foundation for further exploration of ultrahigh-dose-rate irradiation and its potential applications in radiotherapy research.