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The ability to accurately measure the shapes of faint objects in images taken with the Advanced Camera for Surveys(ACS) on the Hubble Space Telescope (HST) depends upon detailed knowledge of the Point Spread Function (PSF). We show that…

This paper describes the on-telescope performance of the Wide Field Spectrograph (WiFeS). The design characteristics of this instrument, at the Research School of Astronomy and Astrophysics (RSAA) of the Australian National University (ANU)…

Instrumentation and Methods for Astrophysics · Physics 2010-02-25 Michael Dopita , Jonghwan Rhee , Catherine Farage , Peter McGregor , Gabe Bloxham , Anthony Green , Bill Roberts , Jon Nielson , Greg Wilson , Peter Young

Adaptive optics enables the deployment of interferometer-based spectroscopy without the need for moving parts necessary for scanning the interferometer arms. Here, we employ a Michelson Interferometer in conjunction with a Spatial Light…

Optics · Physics 2025-12-05 Jesneil Lauren Lewis , Ayan Banerjee

The AdS/CFT correspondence has led to important insights into the properties of quantum chromodynamics even though QCD is a broken conformal theory. A holographic model based on a truncated AdS space can be used to obtain the hadronic…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky , G. F. de Teramond

Scattering-assisted synthesis of broadband optical pulses is recognized to have a cross-disciplinary funda-mental and application importance. Achieving full-waveform synthesis generally requires means for assessing the instantaneous…

We model the large-scale linear galaxy bias $b_g(x,z)$ as a function of redshift $z$ and observed absolute magnitude threshold $x$ for broadband continuum emission from the far infrared to ultra-violet, as well as for prominent emission…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-05 Hengxing Pan , Danail Obreschkow , Cullan Howlett , Claudia del P. Lagos , Pascal J. Elahi , Carlton Baugh , Violeta Gonzalez-Perez

Accurate shape measurements are essential to infer cosmological parameters from large area weak gravitational lensing studies. The compact diffraction-limited point-spread function (PSF) in space-based observations is greatly beneficial,…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-20 Xinzhong Er , Henk Hoekstra , Tim Schrabback , Vincenzo F. Cardone , Roberto Scaramella , Roberto Maoli , Martina Vicinanza , Bryan Gillis , Jason Rhodes

This paper introduces the design and implementation of WiField, a WiFi sensing system deployed on COTS devices that can simultaneously identify multiple wavelength-level targets placed flexibly. Unlike traditional RF sensing schemes that…

Signal Processing · Electrical Eng. & Systems 2024-12-10 Fei Shang , Haocheng Jiang , Panlong Yang , Dawei Yan , Haohua Du , Xiang-Yang Li

Fringing in CCD images is troublesome from the aspect of photometric quality and image flatness in the final reduced product. Additionally, defringing during calibration requires the inefficient use of time during the night to collect and…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Steve B. Howell

Periodic photonic structures enable precise control over the light-matter interaction through band structure engineering. Certain lattice geometries exhibit dispersionless flat bands, characterized by vanishing group velocity and diverging…

Elastic light scattering has been extensively used to study samples showing a non uniform refraction index on lengthscales from a fraction of a micrometer to a fraction of a millimeter. Typically, a wide laser beam is sent through the…

Optics · Physics 2009-07-21 Doriano Brogioli

The off-axis location of the Advanced Camera for Surveys (ACS) is the chief (but not sole) cause of strong geometric distortion in all detectors: the Wide Field Camera (WFC), High Resolution Camera (HRC), and Solar Blind Camera (SBC).…

To meet the growing demand for high data rates, cellular systems are expected to evolve towards higher carrier frequencies and larger antenna arrays, but conventional phased arrays face challenges in supporting such a prospection due to…

Signal Processing · Electrical Eng. & Systems 2025-02-06 Zicheng Lin , Shuhao Zeng , Aryan Kaushik , Hongliang Zhang

The interplay between large antenna apertures and high carrier frequencies in future wireless systems gives rise to near-field communications, where the curvature of spherical wavefronts renders traditional far-field beamforming models…

Signal Processing · Electrical Eng. & Systems 2025-12-02 Panagiotis Gavriilidis , George C. Alexandropoulos

We describe the results of atomic-level stick-slip friction measurements performed on chemically-modified graphite, using atomic force microscopy (AFM). Through detailed molecular dynamics simulations, coarse-grained simulations, and…

Materials Science · Physics 2014-06-23 Alex Smolyanitsky , Shuze Zhu , Zhao Deng , Teng Li , Rachel J. Cannara

A Band function has become the standard spectral function used to describe the prompt emission spectra of gamma-ray bursts (GRBs). However, deviations from this function have previously been observed in GRBs detected by BATSE and in…

We have assembled an 8.4 GHz survey of bright, flat-spectrum (alpha > -0.5) radio sources with nearly uniform extragalactic (|b|>10 deg) coverage for sources brighter than S_{4.8 GHz} = 65 mJy. The catalog is assembled from existing…

Investigation of cell structure is hardly imaginable without bright-field microscopy. Numerous modifications such as depth-wise scanning or videoenhancement make this method being state-of-the-art. This raises a question what maximal…

Image and Video Processing · Electrical Eng. & Systems 2020-10-29 Kirill Lonhus , Renata Rychtarikova , Ganna Platonova , Dalibor Stys

The observables in a strong gravitational lens are usually just the image positions and sometimes the flux ratios. We develop a new and simple algorithm which allows a set of models to be fitted exactly to the observations. Taking our cue…

Astrophysics · Physics 2008-11-26 N. W. Evans , H. J. Witt

In the last two decades, Fresnel diffraction (FD) of a plane wave from phase steps has been systematically studied and applied for precise measurements of light wavelength, and height and refractive index of the step. In this study we…

Optics · Physics 2019-06-13 Masoud Ghoorchi-Beygi , Masoomeh Dashtdar
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