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Related papers: Hardness Ratio Estimation in Low Counting X-ray Ph…

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A commonly used measure to summarize the nature of a photon spectrum is the so-called Hardness Ratio, which compares the number of counts observed in different passbands. The hardness ratio is especially useful to distinguish between and…

In the context of assessing and characterizing structures in X-ray images, we compare different approaches. Most often the intensity level is very low and necessitates a special treatment of Poisson statistics. The method based on wavelet…

Astrophysics · Physics 2009-10-30 Jean-Luc Starck , Marguerite Pierre

Interpretation of x-ray absorption near-edge structure (XANES) experiments is often done via analyzing the role of particular atoms in the formation of specific peaks in the calculated spectrum. Typically, this is achieved by calculating…

Condensed Matter · Physics 2009-11-07 Ondrej Sipr

We present a new technique called "quantile analysis" to classify spectral properties of X-ray sources with limited statistics. The quantile analysis is superior to the conventional approaches such as X-ray hardness ratio or X-ray color…

Astrophysics · Physics 2009-11-10 Jaesub Hong , Eric M. Schlegel , Jonathan E. Grindlay

We present a rigorous description of the general problem of aperture photometry in high energy astrophysics photon-count images, in which the statistical noise model is Poisson, not Gaussian. We compute the full posterior probability…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 F. A. Primini , V. L. Kashyap

X-ray is a ubiquitous imaging modality in clinical diagnostics and industrial inspections, thanks to its high penetration power. Conventional x-ray imaging system, equipped with energy-integrating detectors, collects approximately 1000 to…

Medical Physics · Physics 2020-08-24 Zheyuan Zhu , Shuo Pang

The technique of estimating redshifts using photometric rather than spectroscopic observations has recently received great attention due to its simplicity and the accuracy of the results obtained. In this work, we estimate photometric…

Astrophysics · Physics 2007-05-23 S. Kitsionas , E. Hatziminaoglou , I. Georgantopoulos , A. Georgakakis , O. Giannakis

The compositeness $X$ is defined as the probability to observe the composite structure such as the hadronic molecule component in a bound state. One of the model-independent approaches to calculate $X$ is the weak-binding relation. However,…

High Energy Physics - Phenomenology · Physics 2022-11-30 Tomona Kinugawa , Tetsuo Hyodo

The X-ray color (hardness ratio) of optically undetected X-ray sources can be used to distinguish obscured active galactic nuclei (AGNs) at low and intermediate redshift from viable high-redshift (i.e., z>5) AGN candidates. This will help…

Astrophysics · Physics 2009-11-10 J. X. Wang , S. Malhotra , J. E. Rhoads , C. A. Norman

Kernel density estimation is a convenient way to estimate the probability density of a distribution given the sample of data points. However, it has certain drawbacks: proper description of the density using narrow kernels needs large data…

Data Analysis, Statistics and Probability · Physics 2015-02-27 Anton Poluektov

A method for estimating the relative content of crystalline phases of a multiphase sample, based on probabilistic analysis of the intensities of the diffraction pattern reflexes, has been developed. The method is based on the introduction…

Materials Science · Physics 2023-11-21 S. V. Gabielkov , I. V. Zhyganiuk , A. D. Skorbun

Spectrographs take snapshots of photon spectra with array detectors by dispersing photons of different energies into distinct directions and spacial locations. Spectrographs require optics with a large angular dispersion rate as the key…

Optics · Physics 2013-05-28 Yuri Shvyd'ko , Stanislav Stoupin , Kiran Mundboth , Jungho Kim

Absorption imaging of ultracold atoms is the foundation for quantitative extraction of information from experiments with ultracold atoms. Due to the limited exposure time available in these systems, the signal-to-noise ratio is largest for…

Purpose: Electron density is the most important tissue property influencing photon and ion dose distributions in radiotherapy patients. Dual-energy computed tomography (DECT) enables the determination of electron density by combining the…

Medical Physics · Physics 2017-06-29 Christian Möhler , Patrick Wohlfahrt , Christian Richter , Steffen Greilich

We explore an alternative to the usual procedure of scanning for determining the properties of a narrow $s$-channel resonance. By varying the beam energy resolution while sitting on the resonance peak, the width and branching ratios of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. Casalbuoni , A. Deandrea , S. De Curtis , D. Dominici , R. Gatto , J. F. Gunion

The core theme of X-ray crystallography is reconstructing the electron density distribution of crystals under the constraints of observed diffraction data. Nevertheless, the reconstruction of electron density distribution by straightforward…

Materials Science · Physics 2015-07-14 Hui Li , Meng He , Ze Zhang

The lateral resolution of an X-ray photoelectron spectroscopy instrument, which is equipped with a focused X-ray beam, is limited by the nominal X-ray beam diameter and the long tail intensity distri-bution of the X-ray beam. The long tail…

Instrumentation and Detectors · Physics 2020-12-21 Uwe Scheithauer

High energy resolution, hard X-ray spectroscopies are powerful element selective probes of the electronic and local structure of matter, with diverse applications in chemistry, physics, biology and materials science. The routine application…

Instrumentation and Detectors · Physics 2016-11-03 Zoltán Németh , Jakub Szlachetko , Éva G. Bajnóczi , György Vankó

The determination of fundamental parameters in X-ray luminous (persistent) X-ray binaries has been classically hampered by the large optical luminosity of the accretion disc. New methods, based on irradiation of the donor star and burst…

Astrophysics · Physics 2009-11-11 Jorge Casares , Phil Charles

We present a system of X-ray photometry for the Chandra satellite. X-ray photometry can be a powerful tool to obtain flux estimates, hardness ratios, and colors unbiased by assumptions about spectral shape and independent of temporal and…

Astrophysics · Physics 2008-12-18 H. -J. Grimm , J. McDowell , G. Fabbiano , M. Elvis
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