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Abstract In this work, we examine the effects of spatial dephasing of coherences on the transmission and reflection probabilities for electrons with energyEincident to a one-dimensional rectangular barrier of heightV0. Statistical models are presented where the coherence between different scattering pathways or ‘Feynman paths’ undergo dephasing over a length scale,Lϕ. For incident waves withE>V0, three different dephasing models that attenuate the contributions of spatial coherence to the transmission and reflection probabilities while preserving unitarity (i.e., conserving charge) were investigated. In the tunneling regime (incident waves withE<V0), however, preserving unitarity requiresLϕ→ ∞ , suggesting that elastic tunneling through a rectangular barrier is 100% spatially coherent for these dephasing models. However, wave absorption models are shown to preserve unitarity in the tunneling regime, which is not the case for scattering above the barrier.
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This content will become publicly available on September 18, 2026
Measurements of the Perpendicular Correlation Length of Coronal Alfvénic Waves with DKIST
Abstract We have measured the perpendicular correlation lengthL⊥of Alfvénic waves in the corona using data from the Daniel K. Inouye Solar Telescope (DKIST) Cryogenic Near Infrared Spectropolarimeter (Cryo-NIRSP) instrument. These data have high spatial resolution and were collected using a raster, enabling us to unambiguously identify the parallel and perpendicular directions with respect to the wave propagation. We find that the measured medianL⊥ ≈ 3.5 Mm, which is about half the value found by previous measurements. We ascribe the smaller value measured here to the improved spatial resolution of DKIST. There is a gradual decrease ofL⊥as a function of frequency. We also computed the spatial correlation length of the observed static density structures and found that their typical correlation lengths of ≈8.4 Mm were significantly larger than those of the waves.
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- PAR ID:
- 10651266
- Publisher / Repository:
- Astrophysical Journal
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 991
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 97
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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