24–30 Sept 2017
La Biodola, Isola d'Elba
Europe/Rome timezone

Ultrafast pulsed proton radiolysis in water: Delayed solvation time of electron

28 Sept 2017, 17:00
15m
SB1, Sala Bonaparte 1, HH

SB1, Sala Bonaparte 1, HH

talk WG4 - Applications of Compact and High-Gradient Accelerators WG4_Parallel

Speaker

Dr Brendan Dromey (Queen's University Belfast)

Description

Bursts of laser driven protons have recently been shown to provide the basis for the study of ultrafast ion-matter interactions in both solid [1] and liquid [2] states. This is allowing the first real time study of the evolution of a key species in of water chemistry - the solvated electron. Formed when polar water molecules re-orientate to shield the charge of free ionised electrons, the solvation process leads to the formation of this long lived highly reactive species that can seed the formation of potent radicals. Here we show that the interaction of protons in water leads to a delay in the growth of the photoabsorption band of the solvated electron in comparison to that generated by fast electrons/X-rays. For our conditions we show that this time extends to 100’s of picoseconds (ps, 10^-12s) under proton irradiation. Our initial interpretation is that proton stopping in water leads nanocavitation in the Bragg region which in turns leads to increased thermal motion of the surround water molecules, thus inhibiting the solvation process. [1]Dromey et al., Nat.Comms.,4, 1763 (2013) [2]Senje et al., App. Phys. Letts., 110, 104102 (2017);

Primary author

Dr Brendan Dromey (Queen's University Belfast)

Presentation materials