Results 111 to 120 of about 3,790 (296)

Optical Skyrmions with Tunable or Reconfigurable Topology Using Spin‐Decoupled Metaoptics

Laser &Photonics Reviews, EarlyView.
The work introduces advanced optical elements capable of generating and dynamically reconfiguring complex light patterns known as optical skyrmions. By precisely shaping light polarization at the nanoscale, a single engineered metasurface can generate and manipulate robust and tunable polarization textures in an efficient and scalable way.
Andrea Vogliardi, Daniele Bonaldo, Simone Dal Zilio, Vittorio Apolloni, Filippo Romanato, Gianluca Ruffato   +5 more
wiley   +1 more source

The Atacama Cosmology Telescope: Millimeter Observations of a Population of Asteroids or: ACTeroids

The Astrophysical Journal
We present fluxes and light curves for a population of asteroids at millimeter wavelengths, detected by the Atacama Cosmology Telescope (ACT) over 18,000 deg ^2 of the sky using data from 2017 to 2021.
John Orlowski-Scherer, Ricco C. Venterea, Nicholas Battaglia, Sigurd Naess, Tanay Bhandarkar, Emily Biermann, Erminia Calabrese, Mark Devlin, Jo Dunkley, Carlos Hervías-Caimapo, Patricio A. Gallardo, Matt Hilton, Adam D. Hincks, Kenda Knowles, Yaqiong Li, Jeffrey J McMahon, Michael D. Niemack, Lyman A. Page, Bruce Partridge, Maria Salatino, Jonathan Sievers, Cristóbal Sifón, Suzanne Staggs, Alexander van Engelen, Cristian Vargas, Eve M. Vavagiakis, Edward J. Wollack   +26 more
doaj   +1 more source

Antarctic astronomy

, 2008
John Storey is a Professor of Physics at the University of New South Wales. He was awarded the Pawsey Medal by Australian Academy of Science and the Antarctic Service Medal of the US Congress.
Bhathal, Ragbir (R7283)
core  

Optical‐to‐Microcomb Stability Transfer for Ultrastable Timing and Microwave/Millimeter‐Wave Generation

Laser &Photonics Reviews, EarlyView.
This work demonstrates a high‐fidelity stability transfer from an optical reference to a high‐repetition‐rate microcomb using a mode‐locked laser bridge. By employing electro‐optic sampling timing detection, femtosecond‐level synchronization and 10−18‐level fractional frequency stability are achieved.
Changmin Ahn, Junyong Choi, Daewon Suk, Hansuek Lee, Jungwon Kim   +4 more
wiley   +1 more source

Predictions of Dust Continuum Emission from a Potential Circumplanetary Disk: A Case Study of the Planet Candidate AB Aurigae b

The Astrophysical Journal
Gas-accreting planets embedded in protoplanetary disks are expected to show dust thermal emission from their circumplanetary disks (CPDs). However, a recently reported gas-accreting planet candidate, AB Aurigae b, has not been detected in (sub)millimeter
Yuhito Shibaike, Jun Hashimoto, Ruobing Dong, Christoph Mordasini, Misato Fukagawa, Takayuki Muto   +5 more
doaj   +1 more source

Early infrared astronomy

, 2009
International audienceI present a short history of infrared astronomy, from the first scientific approaches of the `radiant heat' in the seventeenth century to the 1970's, the time when space infrared astronomy was developing very rapidly.
Lequeux, James
core  

Four Directions, One Solution: Enabling Rapid Diffusion Tensor MRI for Ultra‐Low Field Using Deep Learning

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose This study revisits the tetrahedral encoding strategy originally proposed to accelerate Diffusion Tensor Magnetic Resonance Imaging (DT‐MRI) by reducing the requisite number of diffusion‐weighted measurements to four. We examine its practical limitations and explore how artificial intelligence (AI) can extend its utility. Specifically,
Joshua Mawuli Ametepe, James Gholam, Leandro Beltrachini, Mara Cercignani, Derek Kenton Jones   +4 more
wiley   +1 more source

Fourier Shell Analysis: k‐Space‐Based Metrics for Assessing Super‐Resolution in 4D Flow MRI

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose To support the emerging field of super‐resolution (SR) in 4D flow MRI by proposing Fourier shell analysis to disentangle resolution enhancement from denoising effects during evaluation. Methods A thoracic aortic 4D flow MRI dataset was synthesized with various degrees of stenosis, providing ground truth flow fields generated using ...
Luuk Jacobs, Pietro Dirix, Sebastian Kozerke   +2 more
wiley   +1 more source

Constraints on the Gas-phase C/O Ratio of DR Tau's Outer Disk from CS, SO, and C2H Observations

The Astrophysical Journal
Millimeter wavelength observations of Class II protoplanetary disks often display strong emission from hydrocarbons and high CS/SO values, providing evidence that the gas-phase C/O ratio commonly exceeds 1 in their outer regions.
Jane Huang, Edwin A. Bergin, Romane Le Gal, Sean M. Andrews, Jaehan Bae, Luke Keyte, J. A. Sturm   +6 more
doaj   +1 more source

Prospective Head Motion Correction in T1‐ and T2‐Weighted Long Echo Train Sequences Using Servo Navigation

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose To integrate MR‐based servo navigation in MPRAGE and 3D‐TSE sequences and demonstrate its potential for prospective head motion correction in structural imaging. Methods Repeated modules of servo navigators were inserted before each preparation pulse of MPRAGE and 3D‐TSE sequences (before‐prep) for rapid convergence of motion parameter
Matthias Serger, Malte Riedel, Rüdiger Stirnberg, Thomas Ulrich, Nicolas Boulant, Klaas P. Pruessmann, Tony Stöcker, Philipp Ehses   +7 more
wiley   +1 more source