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The amplification obtained using weak values is quantified through a detailed investigation of the signal to noise ratio for an optical beam deflection measurement. We show that for a given deflection, input power and beam radius, the use…

Quantum Physics · Physics 2009-10-14 David J. Starling , P. Ben Dixon , Andrew N. Jordan , John C. Howell

A blind source separation method is described to extract sources from data mixtures where the underlying sources are assumed to be sparse and uncorrelated. The approach used is to detect and analyse segments of time where one source exists…

Signal Processing · Electrical Eng. & Systems 2018-02-06 Malcolm Woolfson

This paper concerns the inverse source scattering problems of recovering random sources for acoustic and elastic waves. The underlying sources are assumed to be random functions driven by an additive white noise. The inversion process aims…

Numerical Analysis · Mathematics 2024-12-10 Yan Chang , Yukun Guo , Zhipeng Yang , Yue Zhao

Transient detection and flux measurement via image subtraction stand at the base of time domain astronomy. Due to the varying seeing conditions, the image subtraction process is non-trivial, and existing solutions suffer from a variety of…

Instrumentation and Methods for Astrophysics · Physics 2016-10-12 Barak Zackay , Eran O. Ofek , Avishay Gal-Yam

The shape of the curves defined by the counts of radio sources per unit area as a function of their flux density was one of the earliest cosmological probes. Radio source counts continue to be an area of interest, used to study the relative…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Ian Heywood , Matt J. Jarvis , James J. Condon

Sensor noise sources cause differences in the signal recorded across pixels in a single image and across multiple images. This paper presents a Bayesian approach to decomposing and characterizing the sensor noise sources involved in imaging…

Flux-resolved X-ray spectroscopy is widely adopted to investigate the spectral variation of a target between various flux levels. In many cases it is done through horizontally splitting a single light curve into multiple flux levels with…

High Energy Astrophysical Phenomena · Physics 2023-01-03 Jia-Lai Kang , Jun-Xian Wang

We present a method of reliably extracting the flux of individual sources from sky maps in the presence of noise and a source population in which number counts are a steeply falling function of flux. The method is an extension of a standard…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 T. M. Crawford , E. R. Switzer , W. L. Holzapfel , C. L. Reichardt , D. P. Marrone , J. D. Vieira

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

Estimating the true background in an astronomical image is fundamental to detecting faint sources. In a typical low-photon count astronomical image, such as in the far and near-ultraviolet wavelength range, conventional methods relying on…

Instrumentation and Methods for Astrophysics · Physics 2024-11-27 Pushpak Pandey , Kanak Saha

We describe a simple method to determine the reliability of source finders based on the detection of sources with both positive and negative total flux. Under the assumption that the noise is symmetric and that real sources have positive…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 P. Serra , R. Jurek , L. Floer

Power spectrum estimation is an important tool in many applications, such as the whitening of noise. The popular multitaper method enjoys significant success, but fails for short signals with few samples. We propose a statistical model…

Statistics Theory · Mathematics 2018-12-10 Joakim Andén , Amit Singer

Quantitative information about variations in the background at J and K' are presented and used to develop guidelines for the acquisition and reduction of ground-based images of faint extended sources in the near-infrared, especially those…

Astrophysics · Physics 2009-11-10 Ovidiu Vaduvescu , Marshall L. McCall

The precision of intensity measurements of the extragalactic X-ray Background (XRB) on an angular scale of about a degree is dominated by spatial fluctuations caused by source confusion noise. X-ray source counts at the flux level…

Astrophysics · Physics 2009-10-30 X. Barcons , A. C. Fabian , F. J. Carrera

The extended source effect on microlensing magnification is non-negligible and must be taken into account for in an analysis of microlensing. However, the evaluation of the extended source magnification is numerically expensive because it…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 Sunao Sugiyama

We present a statistical method based on a maximum likelihood approach to constrain the number counts of extragalactic sources below the nominal flux-density limit of continuum imaging surveys. We extract flux densities from a radio map…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 Ketron Mitchell-Wynne , Mario G. Santos , Jose Afonso , Matt J. Jarvis

The near future of astrophysics involves many large solid-angle, multi-epoch, multi-band imaging surveys. These surveys will, at their faint limits, have data on large numbers of sources that are too faint to be detected at any individual…

Astrophysics · Physics 2014-11-18 Dustin Lang , David W. Hogg , Sebastian Jester , Hans-Walter Rix

We study an inverse problem for the wave equation where localized wave sources in random scattering media are to be determined from time resolved measurements of the waves at an array of receivers. The sources are far from the array, so the…

Mathematical Physics · Physics 2016-07-18 Liliana Borcea , Ilker Kocyigit

If part of a population is hidden but two or more sources are available that each cover parts of this population, dual- or multiple-system(s) estimation can be applied to estimate this population. For this it is common to use the log-linear…

Methodology · Statistics 2023-11-06 Daan B. Zult , Peter G. M. van der Heijden , Bart F. M. Bakker

In high-energy astrophysics, it is common practice to account for the background overlaid with the counts from the source of interest with the help of auxiliary measurements carried on by pointing off-source. In this "on/off" measurement,…

Instrumentation and Methods for Astrophysics · Physics 2014-12-12 Diego Casadei