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arXiv · 2410.14271

Low-energy elastic scattering of electrons from 2H-pyran and 4H-pyran with time delay analysis of resonances

Abstract

Elucidating the significance of low-energy electrons in the rupture of DNA/RNA and the process involved in it is crucial in the field of radiation therapy. Capturing of the incident electron in one of the empty molecular orbitals and the formation of a temporary negative ion (TNI) is considered to be a stepping stone towards the lesion of DNA/RNA. This TNI formation manifests itself as a resonance peak in the cross-sections determined for the electron-molecule interaction. In the present work, we have reported the integral (ICS), differential (DCS), and momentum transfer (MTCS) cross-sections for the elastic scattering of low-energy electrons from the isomers, 2H-pyran and 4H-pyran $\rm{(C_5H_6O)}$, which are analogues of the sugar backbone of DNA. The single-center expansion method has been employed for the scattering calculations. Further, we have used the time delay approach to identify and analyze the resonance peaks. Our results for the ICS and DCS compare well with the only data available in the literature. MTCS data for 2H-pyran and 4H-pyran have been reported for the first time. Moreover, we have also identified an extra peak for each molecule, from time delay analysis, which might be a potential resonance.

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Snigdha Sharma, Dhanoj Gupta. 2024-10-18. Low-energy elastic scattering of electrons from 2H-pyran and 4H-pyran with time delay analysis of resonances. https://arxiv.org/abs/2410.14271

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