Zeptosecond dynamics in atoms: fact or fiction?

• Main Authors: Nandi, T, Sharma, Prashant, Chatterjee, Soumya, Mitra, D, Mishra, Adya P, Azuma, Y, Koike, F, Kheifets, A. S
• Format: Journal Article
• Language: English
• Published: 27-07-2021
• Subjects: Physics - Atomic Physics
• DOI: 10.48550/arxiv.2107.13150

Photon exchange due to nuclear bremsstrahlung during nuclear collisions can
cause Coulomb excitation in the projectile and the target nuclei. The
corresponding process originated in nuclear timescales can also be observed in
atomic phenomenon experimentally if it delayed by at least with an attosecond
or longer timescales. We have found that this happens due to a mechanism
involving the Eisenbud-Wigner-Smith time delay process. We have estimated
photoionization time delays in atomic collisions utilizing the nonrelativistic
version of random phase approximation with exchange and Hartree-Fock methods.
We present three representative processes in which we can observe the phenomena
in attosecond timescales even though they originate from excitations in the
zeptosecond timescales. Thus the work represents an investigation of parallels
between two neighboring areas of physics. Furthermore the present work suggests
new possibilities for atomic physics research near the Coulomb barrier energy,
where the laser is replaced by nuclear bremsstrahlung.