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Full-Text Articles in Physical Sciences and Mathematics
Hyperspectral Infrared Imaging Of Surface Phonon-Polaritons In Srtio3, D. J. Lahneman, M. M. Qazilbash
Hyperspectral Infrared Imaging Of Surface Phonon-Polaritons In Srtio3, D. J. Lahneman, M. M. Qazilbash
Arts & Sciences Articles
Polaritons have a demonstrated impact on nanophotonic applications in the midinfrared through visible spectral range. Surface phonon-polaritons (SPhPs) offer a way to bring the potential of polaritons to the longer infrared wavelengths. Strontium titanate (STO) is a perovskite polar dielectric with diverse technologically advantageous properties and it can support SPhPs in a uniquely broad spectral range of the far infrared. Despite these advantages, STO has mostly been overlooked as a nanophotonic material. In this work we investigate SPhP propagation in STO in the far-infrared through midinfrared spectral range using broadband, near-field nanospectroscopy. We developed a tabletop, laser sustained plasma light …
Toponym-Assisted Map Georeferencing: Evaluating The Use Of Toponyms For The Digitization Of Map Collections, Karim Bahgat, Daniel Runfola
Toponym-Assisted Map Georeferencing: Evaluating The Use Of Toponyms For The Digitization Of Map Collections, Karim Bahgat, Daniel Runfola
Arts & Sciences Articles
A great deal of information is contained within archival maps—ranging from historic political boundaries, to mineral resources, to the locations of cultural landmarks. There are many ongoing efforts to preserve and digitize historic maps so that the information contained within them can be stored and analyzed efficiently. A major barrier to such map digitizing efforts is that the geographic location of each map is typically unknown and must be determined through an often slow and manual process known as georeferencing. To mitigate the time costs associated with the georeferencing process, this paper introduces a fully automated method based on map …
Measurement Of The Beam-Normal Single-Spin Asymmetry For Elastic Electron Scattering From ^12c And ^27al, D. Androic, David S. Armstrong, Et Al.
Measurement Of The Beam-Normal Single-Spin Asymmetry For Elastic Electron Scattering From ^12c And ^27al, D. Androic, David S. Armstrong, Et Al.
Arts & Sciences Articles
We report measurements of the parity-conserving beam-normal single-spin elastic scattering asymmetries Bn on 12C and 27Al, obtained with an electron beam polarized transverse to its momentum direction. These measurements add an additional kinematic point to a series of previous measurements of Bn on 12C and provide a first measurement on 27Al. The experiment utilized the Qweak apparatus at Jefferson Lab with a beam energy of 1.158 GeV. The average laboratory scattering angle for both targets was 7.7∘, and the average Q2 for both targets was 0.024 37 GeV2 (Q=0.1561 GeV). The asymmetries are Bn=−10.68±0.90(stat)±0.57(syst) ppm for 12C and Bn=−12.16±0.58(stat)±0.62(syst) ppm …
Predicting Road Quality Using High Resolution Satellite Imagery: A Transfer Learning Approach, Ethan Brewer, Jason Lin, Peter Kemper, John Hennin, Daniel Runfola
Predicting Road Quality Using High Resolution Satellite Imagery: A Transfer Learning Approach, Ethan Brewer, Jason Lin, Peter Kemper, John Hennin, Daniel Runfola
Arts & Sciences Articles
Recognizing the importance of road infrastructure to promote human health and economic development, actors around the globe are regularly investing in both new roads and road improvements. However, in many contexts there is a sparsity—or complete lack—of accurate information regarding existing road infrastructure, challenging the effective identification of where investments should be made. Previous literature has focused on overcoming this gap through the use of satellite imagery to detect and map roads. In this piece, we extend this literature by leveraging satellite imagery to estimate road quality and concomitant information about travel speed. We adopt a transfer learning approach in …
Accurate Determination Of The Neutron Skin Thickness Of ^208pb Through Parity-Violation In Electron Scattering, D. Adhikari, (...), David S. Armstrong, Et Al.
Accurate Determination Of The Neutron Skin Thickness Of ^208pb Through Parity-Violation In Electron Scattering, D. Adhikari, (...), David S. Armstrong, Et Al.
Arts & Sciences Articles
We report a precision measurement of the parity-violating asymmetry APV in the elastic scattering of longitudinally polarized electrons from 208Pb. We measure APV=550±16(stat)±8(syst) parts per billion, leading to an extraction of the neutral weak form factor FW(Q2=0.00616 GeV2)=0.368±0.013. Combined with our previous measurement, the extracted neutron skin thickness is Rn−Rp=0.283±0.071 fm. The result also yields the first significant direct measurement of the interior weak density of 208Pb: ρ0W=−0.0796±0.0036(exp)±0.0013(theo) fm−3 leading to the interior baryon density ρ0b=0.1480±0.0036(exp)±0.0013(theo) fm−3. The measurement accurately constrains the density dependence of the symmetry energy of nuclear matter near saturation density, with implications for the size and …
Partially Metal-Coated Tips For Near-Field Nanospectroscopy, Yujia Zhang, Xinzhong Chen, (...), M. M. Qazilbash, Et Al.
Partially Metal-Coated Tips For Near-Field Nanospectroscopy, Yujia Zhang, Xinzhong Chen, (...), M. M. Qazilbash, Et Al.
Arts & Sciences Articles
Scanning probes with functional optical responses are key components of scanning near-field optical microscopes. For nanospectroscopy performed at IR and terahertz (THz) frequencies, one major challenge is that the commonly used metal-coated silicon tips yield nonadjustable coupling efficiency across the spectrum, which greatly limits the signal-to-noise ratio. Here, we test the possibility of a generic design scheme for wavelength-selective tip enhancement via finite-element numerical modeling. We employ a Si-based tip with various gold-coating lengths on the top, yielding a customizable near-field field strength at the tip apex. Calculations show a wavelength-dependent enhancement factor of the metal-coated tip due to the …