Ref HAL: hal-03926349_v1
Ref Arxiv: 2301.01175
Ref INSPIRE: 2620606
Ref. & Cit.: NASA ADS
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Abstract:

We report an efficient approach to accurately and efficiently compute transmission probabilities in resonant deep tunneling regime. Dynamical systems subjects to this phenomenon prove hard to simulate numerically even with exact methods, which motivates new methodological developments owing to the impact resonant phenomena have in several processes such as chemical reactions and electronic transport. Our approach is based on the original reformulation of stationnary quantum scattering as the propagation of a quantum trajectory in extended phase space. The present paper discusses in detail the node problem occurring to the time-independent quantum trajectory method in this very challenging situation, and introduces an efficient node-skipping scheme to circumvent expensive numerical integration in their vicinity. We illustrate how this numerical extension allows to treat all regimes of quantum tunneling with great versatility by comparison to existing approaches of the litterature. The quantum trajectory thus represents a very promising tool for the study of complex chemical reactions characterized by resonant tunneling effect.

Ref Arxiv: 2210.07210
DOI: 10.1093/mnras/stad512
Ref. & Cit.: NASA ADS
Abstract:

Line-of-sight effects in strong gravitational lensing have long been treated as a nuisance. However, it was recently proposed that the line-of-sight shear could be a cosmological observable in its own right, if it is not degenerate with lens model parameters. Using the formalism introduced by Fleury et al. (2021a), we firstly demonstrate that the line-of-sight shear can be accurately measured from a simple simulated strong lensing image with percent precision. We then extend our analysis to more complex simulated images and stress test the recovery of the line-of-sight shear when using deficient fitting models, finding that it escapes from degeneracies with lens model parameters, albeit at the expense of the precision. Lastly, we check the validity of the tidal approximation by simulating and fitting an image generated in the presence of many line-of-sight dark matter haloes, finding that an explicit violation of the tidal approximation does not necessarily prevent one from measuring the line-of-sight shear.

Comments: 16 + 3 pages, 14 figures, prepared for submission to MNRAS

Ref HAL: hal-03625359_v1
Ref Arxiv: 2203.16491
Ref INSPIRE: 2060145
DOI: 10.1088/1475-7516/2023/02/004
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote