English
Related papers

Related papers: Design and deployment of radiological point-source…

200 papers

Metric and decametric radio-emissions from the Sun are the only direct source of information about the dynamics of non-thermal electrons in the upper corona. In addition, the combination of spectral and imaging (sizes, shapes, and…

Solar and Stellar Astrophysics · Physics 2022-02-09 M. Gordovskyy , E. P. Kontar , D. L. Clarkson , N. Chrysaphi , P. K. Browning

In this paper we explore the maximum precision attainable in the location of a point source imaged by a pixel array detector in the presence of a background, as a function of the detector properties. For this we use a well-known result from…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Rene Mendez , Jorge Silva , Rodrigo Lobos

The multiscale variance stabilization Transform (MSVST) has recently been proposed for Poisson data denoising. This procedure, which is nonparametric, is based on thresholding wavelet coefficients. We present in this paper an extension of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 J. -L. Starck , J. M. Fadili , S. Digel , B. Zhang , J. Chiang

We use Murchison Widefield Array observations of interplanetary scintillation (IPS) to determine the source counts of point ($<$0.3 arcsecond extent) sources and of all sources with some subarcsecond structure, at 162 MHz. We have developed…

Astrophysics of Galaxies · Physics 2018-07-11 R. Chhetri , R. D. Ekers , J. Morgan , J. -P. Macquart , T. M. O. Franzen

Precise subtraction of foreground sources is crucial for detecting and estimating 21cm HI signals from the Epoch of Reionization (EoR). We quantify how imperfect point source subtraction due to limitations of the measurement dataset yields…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Cathryn M. Trott , Randall B. Wayth , Steven J. Tingay

The ability to formulate maps of minimum detectable activities (MDAs) that describe the sensitivity of an ad hoc measurement that used one or more freely moving radiation detector systems would be significantly beneficial for the conduct…

Instrumentation and Detectors · Physics 2025-03-17 Mark S. Bandstra , Daniel Hellfeld , Jaewon Lee , Brian J. Quiter , Marco Salathe , Jayson R. Vavrek , Tenzing H. Y. Joshi

Air sensor networks provide hyperlocal, high temporal resolution data on multiple pollutants that can support credible identification of common pollution sources. Source apportionment using least squares-based non-negative matrix…

We present a point-source detection algorithm that employs the second order Spherical Mexican Hat wavelet filter (SMHW2), and use it on C-BASS northern intensity data to produce a catalogue of point-sources. This catalogue allows us to…

We develop a computational approach to locate the source of a steady-state gradient of diffusing particles from the fluxes through narrow windows distributed either on the boundary of a three dimensional half-space or on a sphere. This…

Statistical Mechanics · Physics 2020-01-07 U. Dobramysl , D. Holcman

We present a pilot search for variable and transient sources at 1.4 GHz with the Australian Square Kilometre Array Pathfinder (ASKAP). The search was performed in a 30 deg$^{2}$ area centred on the NGC 7232 galaxy group over 8 epochs and…

Precise radon measurements are a requirement for various applications, ranging from radiation protection over environmental studies to material screening campaigns for rare-event searches. All of them ultimately depend on the availability…

Instrumentation and Detectors · Physics 2023-01-25 Florian Jörg , Guillaume Eurin , Hardy Simgen

Statistical properties of photon count maps have recently been proven as a new tool to study the composition of the gamma-ray sky with high precision. We employ the 1-point probability distribution function of 6 years of Fermi-LAT data to…

High Energy Astrophysical Phenomena · Physics 2016-08-01 Hannes-S. Zechlin , Alessandro Cuoco , Fiorenza Donato , Nicolao Fornengo , Marco Regis

We develop a potential algorithm to relate the depth development of ultra high energy extensive air showers and the time delay for individual muons. The time distributions sampled at different positions at ground level by a large air shower…

Astrophysics · Physics 2009-11-10 L. Cazon , R. A. Vazquez , E. Zas

A method is proposed, based on scan statistics, to detect, identify, and localize illicit radiological material using mobile sensors in an urban environment. Our method handles varying levels of background radiation that change according to…

Signal Processing · Electrical Eng. & Systems 2020-02-11 Michael D. Porter , Alphonse Akakpo

We present a stacking method that makes use of co-added maps of gamma-ray counts produced from data taken with the Fermi Large Area Telescope. Sources with low integrated gamma-ray fluxes that are not detected individually may become…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 B. Huber , C. Farnier , A. Manalaysay , U. Straumann , R. Walter

Because of the relatively broad angular resolution of current gamma-ray instruments in the MeV-GeV energy range, the photons of a given source are mixed with those coming from nearby sources or diffuse background. This source confusion…

Instrumentation and Methods for Astrophysics · Physics 2019-02-06 P. Bruel

In the context of atmospheric shower arrays designed for $\gamma$-ray astronomy and in the context of the ALTO project, we present: a study of the impact of heavier nuclei in the cosmic-ray background on the estimated $\gamma$-ray detection…

Instrumentation and Methods for Astrophysics · Physics 2023-03-28 M. Punch , M. Senniappan , Y. Becherini , G. Kukec Mezek , S. Thoudam , T. Bylund , J. -P. Ernenwein

We consider filters for the detection and extraction of compact sources on a background. We make a one-dimensional treatment (though a generalization to two or more dimensions is possible) assuming that the sources have a Gaussian profile…

Astrophysics · Physics 2009-11-10 M. Lopez-Caniego , D. Herranz , R. B. Barreiro , J. L. Sanz

Results from the Modified Three Gradient Method (MTGM), applied to a pulsed high intensity electron source, are presented. The MTGM makes possible the non-destructive determination of beam emittance in the space charge presence [1]. We…

Accelerator Physics · Physics 2007-05-23 S. Marghitu , C. Oproiu , C. Dinca , O. Marghitu

Sparse static detector networks in urban environments can be used in efforts to detect illicit radioactive sources, such as stolen nuclear material or radioactive "dirty bombs". We use detailed simulations to evaluate multiple…

Instrumentation and Detectors · Physics 2025-02-13 E. Rofors , N. Abgrall , M. S. Bandstra , R. J. Cooper , D. Hellfeld , T. H. Y. Joshi , V. Negut , B. J. Quiter , M. Salathe