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We have developed a new technique called Direct Shear Mapping (DSM) to measure gravitational lensing shear directly from observations of a single background source. The technique assumes the velocity map of an un-lensed, stably-rotating…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-26 Catherine O. de Burgh-Day , Edward N. Taylor , Rachel L. Webster , Andrew M. Hopkins

We investigate the fluctuations of linear spectral statistics of a Wigner matrix $W\_N$ deformed by a deterministic diagonal perturbation $D\_N$, around a deterministic equivalent which can be expressed in terms of the free convolution…

Probability · Mathematics 2020-03-17 Sandrine Dallaporta , Maxime Fevrier

We consider a random dynamical system obtained by switching between the flows generated by two smooth vector fields on the 2d-torus, with the random switchings happening according to a Poisson process. Assuming that the driving vector…

Dynamical Systems · Mathematics 2018-03-22 Yuri Bakhtin , Tobias Hurth , Sean D. Lawley , Jonathan C. Mattingly

We study the prospects for three-dimensional mapping of the dark matter to high redshift through the shearing of faint galaxies images at multiple distances by gravitational lensing. Such maps could provide invaluable information on the…

Astrophysics · Physics 2009-08-12 Wayne Hu , Charles R. Keeton

We demonstrate a technique for obtaining the density of atomic vapor, by doing a fit of the resonant absorption spectrum to a density-matrix model. In order to demonstrate the usefulness of the technique, we apply it to absorption in the…

Atomic Physics · Physics 2017-06-15 Harish Ravi , Mangesh Bhattarai , Vasant Natarajan

There is widespread interest in estimating the fluorescence properties of natural materials in an image. However, the separation between reflected and fluoresced components is difficult, because it is impossible to distinguish reflected and…

Computer Vision and Pattern Recognition · Computer Science 2016-05-16 Henryk Blasinski , Joyce Farrell , Brian Wandell

In this work, we explore a numerical approach for performing the inverse Laplace transformation, with an emphasis on achieving stability and robustness under noisy conditions. Our quadrature-based method integrates reparameterization, data…

High Energy Physics - Lattice · Physics 2026-03-03 Marco Aliberti , Francesco Di Renzo , Petros Dimopoulos , Demetrianos Gavriel

Quantitative thermodynamical, dynamical and magnetic properties of the solar and stellar plasmas are obtained by interpreting their emergent non-polarized and polarized spectrum. This inference requires the selection of a set of spectral…

Solar and Stellar Astrophysics · Physics 2016-05-25 A. Asensio Ramos , J. de la Cruz Rodriguez , M. J. Martinez Gonzalez , A. Pastor Yabar

The deduction from solar flare X-ray photon spectroscopic data of the energy dependent model-independent spectral index is considered as an inverse problem. Using the well developed regularization approach we analyze the energy dependency…

Astrophysics · Physics 2009-11-11 Eduard P. Kontar , Alexander L. MacKinnon

We study the fluctuations of the light emitted by two identical incoherent point sources in a disordered environment. The intensity-intensity correlation function and the speckle contrast, obtained after proper temporal and configurational…

Optics · Physics 2015-02-09 R. Carminati , G. Cwilich , L. S. Froufe-Pérez , J. J. Sáenz

X-ray photon correlation spectroscopy (XPCS) allows for the resolution of dynamic processes within a material across a wide range of length and time scales. X-ray speckle visibility spectroscopy (XSVS) is a related method that uses a single…

Numerical Analysis · Mathematics 2023-01-09 Shaswat Mohanty , Christopher B. Cooper , Hui Wang , Mengning Liang , Wei Cai

In this paper, the problem of assessing the twistability of a given bona fide cross-spectral density is tackled for the class of Schell-model sources, whose shift-invariant degree of coherence is represented by a real and symmetric…

Optics · Physics 2025-01-07 Riccardo Borghi

A shearing interferometer is presented which uses polarization control to shear the wavefront and to modulate the interference pattern. The shear is generated by spatial walk-off in a birefringent crystal. By adjusting the orientation of…

Optics · Physics 2012-12-11 Peter Beyersdorf , Mark Cordier

Large-amplitude isothermal fluctuations in the dark matter energy density, parameterized by $\Phi\equiv\delta\rhodm/\rhodm$, are studied within the framework of a spherical collapse model. For $\Phi \ga 1$, a fluctuation collapses in the…

Astrophysics · Physics 2009-10-22 Edward W. Kolb , Igor I. Tkachev

Spectra derived from fast Fourier transform (FFT) analysis of time-domain data intrinsically contain statistical fluctuations whose distribution depends on the number of accumulated spectra contributing to a measurement. The tail of this…

Solar and Stellar Astrophysics · Physics 2015-06-19 Gelu M. Nita , Gregory D. Fleishman , Dale E. Gary , William Marin , Kristine Boone

In this note, we study the convergence from the discrete to the continuous non-linear Fourier transform. Relations between spectral problems and questions in complex function theory provide a new approach to the study of scattering problems…

Classical Analysis and ODEs · Mathematics 2024-08-16 Ashley R. Zhang

We present inversion techniques aiming at recovering the stellar content (age, metallicity, extinction) and kinematics of a stellar population from its absorption line spectrum. These techniques use new synthetic high resolution spectra…

Astrophysics · Physics 2007-05-23 P. Ocvirk , C. Pichon , A. Lancon

We derive spectral sum rules in the shear channel for conformal field theories at finite temperature in general $d\geq 3$ dimensions. The sum rules result from the OPE of the stress tensor at high frequency as well as the hydrodynamic…

High Energy Physics - Theory · Physics 2017-12-12 Subham Dutta Chowdhury , Justin R. David , Shiroman Prakash

We derive in this paper expressions for the covariance matrix of the cosmic shear two-point correlation functions which are readily applied to any survey geometry. Furthermore, we consider the more special case of a simple survey geometry…

Astrophysics · Physics 2009-11-07 Peter Schneider , Ludovic van Waerbeke , Martin Kilbinger , Yannick Mellier

Neutron direct-geometry time-of-flight chopper spectroscopy is instrumental in studying fundamental excitations of vibrational and/or magnetic origin. We report here that techniques in super-resolution optical imagery (which is in…

Data Analysis, Statistics and Probability · Physics 2020-01-08 Fahima Islam , Jiao Y. Y. Lin , Richard Archibald , Douglas L. Abernathy , Iyad Al-Qasir , Anne A. Campbell , Matthew B. Stone , Garrett E. Granroth
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