Search arXivSearch

arXiv · 1908.08728

Pulse dependence of prevalent pathways in xenon driven by an x-ray free-electron-laser pulse

Abstract

We study the interaction of xenon with an 850 eV photon energy FEL pulse. We do so by employing a Monte-Carlo technique. We compute the single-photon ionisation cross sections and Auger rates, used in the Monte-Carlo technique, by adopting to atoms a formalism we previously developed for diatomic molecules. We determine the yields of the ion states of driven xenon and compare with previously obtained experimental results. To better understand the yields obtained, we identify the prevalent pathways leading to the formation of each final ion state of xenon. We gain further insight into the high yields of highly-charged ion states by comparing the yields and dominant pathways of these ion states of xenon when driven by different FEL pulses that have the same energy. We show that higher-charged ion states have higher yields when xenon is driven by longer-duration pulses due to Auger cascades taking place between subsequent single-photon ionisations.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Henry I. B. Banks, Antonis Hadjipittas, Agapi Emmanouilidou. 2019-08-23. Pulse dependence of prevalent pathways in xenon driven by an x-ray free-electron-laser pulse. https://arxiv.org/abs/1908.08728

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

$LS/LSJ$ Hybrid Coupling Framework for Auger Angular Distributions of Experimentally Unresolved Multiplets with Isolated Fine-Structure

We present a hybrid $LS/LSJ$ coupling framework for treating state multiplets in the regime $ΔE_\text{int}\sim\hbar/τ_\text{int} \ggΔE_\text{FS}\ggΓ$, where $τ_\text{int}$ is the collision interaction time, $ΔE_\text{FS}$ the fine-structure splitting, and $Γ$ the natural width. In this regime, the collision interaction is fast compared with fine-structure evolution, whereas the individual $J$ levels are well isolated on the scale of their natural widths. The produced multiplet's alignment is therefore described in $LS$ coupling and then projected onto the individual fine-structure $J$ levels before their subsequent decay, described by $LSJ$ coupling. Applied to the multi-open-shell $1s2s2p\,^4\!P_J$ manifold, which closely satisfies these conditions, the hybrid treatment reveals strong suppression and inversion of the Auger angular-distribution anisotropy relative to the traditional pure-$LS$ treatment. It substantially improves agreement with absolute experimental data while using the same $LS$ production cross sections. This hybrid $LS/LSJ$ framework thus provides the appropriate treatment of state multiplets with isolated fine-structure levels, as it retains the $J$-dependent decay dynamics missing from the traditional pure-$LS$ treatment.

physics.atom-ph

A Protocol for Shielding-Enhanced Loading of Single Polar Molecules into Optical Tweezers

We propose the high-fidelity preparation of single bosonic molecules in optical tweezers starting from small tweezer-trapped molecular ensembles. Our scheme combines a static electric field and a microwave field to generate strong, tunable, anisotropic interactions that shield the molecules against two-body collisional loss. We show that this shielding eliminates all long-range bound states, preventing three-body recombination. This elimination persists for all microwave ellipticities, including the experimentally practical limit of linear polarization. Application of an additional electric field gradient can be used to induce controlled spilling of strongly interacting molecules out of the trap until one remains. With realistic experimental parameters, we estimate that single tweezer-trapped NaCs molecules can be isolated from a pair with fidelities exceeding 99\%, and $> 95\%$ per site across an array. These results establish collisional shielding with electric fields as an effective tool for preparing highly-filled tweezer arrays of polar molecules.

physics.atom-ph

Vector Measurements Using Integrated Radio Frequency Atomic Magnetometers

We demonstrate reconstruction of three-dimensional radio-frequency (RF) magnetic-field vectors using a pair of integrated RF atomic magnetometers operated with orthogonal bias-field orientations. A theoretical and experimental analysis identifies a phase-ambiguity dead band that limits reconstruction when the two sensor responses become nearly identical. Measurements performed in an unshielded laboratory environment demonstrate accurate reconstruction of RF magnetic-field orientations and validate the predicted dependence of reconstruction accuracy on signal imbalance. These results establish integrated RF atomic magnetometers as a compact and sensitive platform for directional RF magnetic-field sensing, particularly at low frequencies, and provide a foundation for portable source-localization and field-mapping applications.

physics.atom-ph