Coupled-channels density-matrix approach to low-energy nuclear reaction dynamics

TL;DR

This paper introduces a coupled-channels density-matrix method to quantify quantum decoherence effects in low-energy nuclear reactions, addressing limitations of traditional models and applying it to astrophysically relevant collisions.

Contribution

It presents a novel density-matrix approach that incorporates quantum decoherence into low-energy nuclear reaction modeling, improving upon traditional coupled-channels methods.

Findings

Quantifies the role of quantum decoherence in nuclear reactions.

Provides a unified quantum dynamical framework for weakly-bound nuclei.

Applied to $^{12}$C + $^{12}$C collision, highlighting astrophysical relevance.

Abstract

Atomic nuclei are complex, quantum many-body systems whose structure manifests itself through intrinsic quantum states associated with different excitation modes or degrees of freedom. Collective modes (vibration and/or rotation) dominate at low energy (near the ground-state). The associated states are usually employed, within a truncated model space, as a basis in (coherent) coupled channels approaches to low-energy reaction dynamics. However, excluded states can be essential, and their effects on the open (nuclear) system dynamics are usually treated through complex potentials. Is this a complete description of open system dynamics? Does it include effects of quantum decoherence? Can decoherence be manifested in reaction observables? In this contribution, I discuss these issues and the main ideas of a coupled-channels density-matrix approach that makes it possible to quantify the role and importance of quantum decoherence in low-energy nuclear reaction dynamics. Topical applications, which refer to understanding the astrophysically important collision $^{12}$C + $^{12}$C and achieving a unified quantum dynamical description of relevant reaction processes of weakly-bound nuclei, are highlighted.