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We report the experimental super-resolution of pairs of point-like fluorescent sources using a modified image inversion interferometer microscope. The technique is inspired by recent developments in the application of quantum parameter…

Flexion-based weak gravitational lensing analysis is proving to be a useful adjunct to traditional shear-based techniques. As flexion arises from gradients across an image, analytic and numerical techniques are required to investigate…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Christopher J. Fluke , Paul D. Lasky

We study the feasibility of applying the Generator Coordinate Method (GCM) of self-consistent mean-field theory to calculate decay widths of composite particles to composite-particle final states. The main question is how well the GCM can…

Nuclear Theory · Physics 2019-03-27 G. F. Bertsch , W. Younes

A computer code is described for the simulation of gravitational lensing data. The code incorporates adaptive mesh refinement in choosing which rays to shoot based on the requirements of the source size, location and surface brightness…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-29 R. Benton Metcalf , Margarita Petkova

Spatial intensity moments computed on images can be used as a probe of the centroid, size, and orientation of pixelized sources such as stars and galaxies. However, all measurements made on images suffer from errors due to undersampling and…

Instrumentation and Methods for Astrophysics · Physics 2020-12-11 Andrew K. Bradshaw

We study the correlations in wave vector space of photon pairs generated by type I spontaneous parametric down conversion using a Gaussian pump beam. We analyze both moderate focused and highly focused regimes taking special attention to…

Quantum Physics · Physics 2015-06-19 Yasser Jeronimo-Moreno , R. Jáuregui

Model equations for describing and efficiently computing the radiation profiles of tightly spherically-focused higher-order electromagnetic beams of vortex nature are derived stemming from a vectorial analysis with the complex-source-point…

Optics · Physics 2020-07-21 F. G. Mitri

We present a new technique to constrain the gravitational potential of a galaxy from the observed stellar mass surface density alone under a number of assumptions. It uses the classical Eddington Inversion Method to compute the phase-space…

Astrophysics of Galaxies · Physics 2025-02-19 Jorge Sanchez Almeida , Ignacio Trujillo , Mireia Montes , Angel R. Plastino

The surface density of submillimeter (sub-mm) galaxies as a function of flux, usually termed the source number counts, constrains models of the evolution of the density and luminosity of starburst galaxies. At the faint end of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 M. Zemcov , A. Blain , M. Halpern , L. Levenson

The Fourier transformation is an effective and efficient operation of Gaussianization at the one-point level. Using a set of N-body simulation data, we verified that the one-point distribution functions of the dark matter momentum…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-05 Ming Li , Jun Pan , Pengjie Zhang , Jie Wang , Longlong Feng , Liang Gao , Xi Kang , Guoliang Li , Weipeng Lin , Haihui Wang

For partially coherent light fields with random fluctuations, the intensity distributions and statistics have been proven to be more propagation robust compared with coherent light. However, its full potential in practical applications has…

Optics · Physics 2023-03-30 Xingyuan Lu , Zhuoyi Wang , Qiwen Zhan , Yangjian Cai , Chengliang Zhao

A probabilistic technique for the joint estimation of background and sources with the aim of detecting faint and extended celestial objects is described. Bayesian probability theory is applied to gain insight into the coexistence of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 F. Guglielmetti , R. Fischer , V. Dose

We study the angular clustering of point sources in The GMRT (Giant Meter Wave Telescope) Sky Survey (TGSS). The survey at 150 MHz with delta > -53.5 degrees has a sky coverage of 3.6 pi steradians, i.e., 90% of the whole sky. We created…

Astrophysics of Galaxies · Physics 2019-06-04 Sandeep Rana , J. S. Bagla

According to literature, while calculating the brightness of synchrotron radiation from wigglers, one needs to account for the so called `depth-of-field' effects. In fact, the particle beam cross section varies along the wiggler. It is…

Accelerator Physics · Physics 2014-12-20 Gianluca Geloni , Vitali Kocharyan , Evgeni Saldin

We present an algorithm capable of detecting diffuse, dim sources of any size in an astronomical image. These sources often defeat traditional methods for source finding, which expand regions around points of high intensity. Extended…

Instrumentation and Methods for Astrophysics · Physics 2016-01-05 T. Butler-Yeoman , M. Frean , C. P. Hollitt , D. W. Hogg , M. Johnston-Hollitt

Ground-based astronomical observations will continue to produce resolution-limited images due to atmospheric seeing. Deconvolution reverses such effects and thus can benefit extracted science in multifaceted ways. We apply the Scaled…

Instrumentation and Methods for Astrophysics · Physics 2025-11-04 Yash Gondhalekar , Richard M. Feder , Matthew J. Graham , Ajit K. Kembhavi , Margarita Safonova , Snehanshu Saha , Ashish A. Mahabal

We prove a gravitational lensing theorem: the magnification of a source of uniform brightness by a foreground spherical lens is mu =1+pi(2R_E^2-R_L^2)/A, where A is the area of the source and R_E and R_L are the Einstein radius and size of…

Astrophysics · Physics 2009-11-07 Eric Agol

Procedures based on current methods to detect sources in X-ray images are applied to simulated XMM images. All significant instrumental effects are taken into account, and two kinds of sources are considered -- unresolved sources…

Astrophysics · Physics 2009-11-06 I. Valtchanov , M. Pierre , R. Gastaud

We show different expressions of distribution functions (DFs) which depend only on the two classical integrals of the energy and the magnitude of the angular momentum with respect to the axis of symmetry for stellar systems with known…

Astrophysics · Physics 2009-06-25 Zhenglu Jiang , Leonid Ossipkov

This paper presents a new method to obtain the deformation distribution on the main reflector of an antenna only by measuring the electric intensity on a spherical surface with the focal point as the center of the sphere, regardless of…

Instrumentation and Methods for Astrophysics · Physics 2021-12-08 Qian Ye , Boyang Wang , Qiang Yao , Jinqing Wang , Qinghui Liu , Zhiqiang Shen