EPJ D Highlight - Investigating positron scattering from giant molecular targets

Positron scattering from a carbon 60 molecule. Positrons can be an important probe of the quantum properties of larger molecules. Credit: Robert Lea.

New research looks at positron scattering from rare gas atoms encapsulated in carbon 60 to investigate quantum properties that can’t be tested with electrons.

Particle scattering is an important test of the quantum properties of atoms and larger molecules. While electrons have historically dominated these experiments, their positively charged antimatter counterparts — positrons — can be used in promising applications when the negatively charged particles aren’t suitable.

A new paper published in EPJ D examines the scattering of positrons from rare gas atoms stuffed inside the fullerenes — so-called “rare gas endohedrals.” The paper is authored by Km Akanksha Dubey from the Indian Institute of Technology Patna, Patna, Bihta, India, and Marcelo Ciappina, Guangdong Technion-Israel Institute of Technology, Shantou, China.

“Our focus was to investigate positron scattering processes with rare gas endohedrals. As a reference to the endohedral system, we also considered positron scattering from bare C60 targets,” Ciappina says. ““In our study, we chose rare gas atoms for encapsulation inside carbon 60 (C60), as they are probably the most popular and studied endohedrals. Rare gas endohedrals are very stable formations; the encapsulated atoms find their equilibrium position at almost the geometrical centre of the C60.”

The study builds upon the findings of previous studies involving the collision of positrons with giant targets like C60 and rare gas endohedrals. The major difference being that the resonance scattering with different sizes of the encaged atoms is elucidated in comparison to the bare C60 scattering; resonances are also tested under the different scattering fields of the projectile-target complex.

“To our surprise, resonance formations in the rare gas endohedrals are altered as compared to the case of positron-C60 collision, despite the dominant scattering field in positron scattering being repulsive in nature,” Ciappina says. The resonances at the lower energy are significantly affected by various scattering fields considered alternatively.

“Thus, scattering resonances in the positron scattering find their natural abode in the C60 and rare gas endohedrals, and the resonance states can be favourably manipulated by keeping the rare gas atoms inside it.”

With insights into many aspects of such collision processes, potential applications for the findings of the paper could range from fields such as positron beam spectroscopy and the investigation of nanomaterials.

Dubey, K.A., Ciappina, M.F. Positron scattering from C60 and rare gas endohedrals. Eur. Phys. J. D 76, 66 (2022).

This was our first experience of publishing with EPJ Web of Conferences. We contacted the publisher in the middle of September, just one month prior to the Conference, but everything went through smoothly. We have had published MNPS Proceedings with different publishers in the past, and would like to tell that the EPJ Web of Conferences team was probably the best, very quick, helpful and interactive. Typically, we were getting responses from EPJ Web of Conferences team within less than an hour and have had help at every production stage.
We are very thankful to Solange Guenot, Web of Conferences Publishing Editor, and Isabelle Houlbert, Web of Conferences Production Editor, for their support. These ladies are top-level professionals, who made a great contribution to the success of this issue. We are fully satisfied with the publication of the Conference Proceedings and are looking forward to further cooperation. The publication was very fast, easy and of high quality. My colleagues and I strongly recommend EPJ Web of Conferences to anyone, who is interested in quick high-quality publication of conference proceedings.

On behalf of the Organizing and Program Committees and Editorial Team of MNPS-2019, Dr. Alexey B. Nadykto, Moscow State Technological University “STANKIN”, Moscow, Russia. EPJ Web of Conferences vol. 224 (2019)

ISSN: 2100-014X (Electronic Edition)

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