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Related papers: Elliptical X-Ray Spot Measurement

200 papers

Novel schemes for generating ultra-low emittance electron beams have been developed in the last years and promise compact particle sources with excellent beam quality suitable for future high-energy physics experiments and free-electron…

Accelerator Physics · Physics 2021-01-28 Andreas Seidel , Jens Osterhoff und Matt Zepf

A simple means of detecting and spatially mapping volatile and nonvolatile conductive filaments in metal/oxide/metal cross-point devices is introduced and its application demonstrated. The technique is based on thermal discolouration of a…

Applied Physics · Physics 2018-11-30 Shimul Kanti Nath , Sanjoy Kumar Nandi , Shuai Li , Robert Glen Elliman

Infrared spectroscopy currently requires the use of bulky, expensive, and/or fragile spectrometers. For gas sensing, environmental monitoring, or other applications in the field, an inexpensive, compact, robust on-chip spectrometer is…

Optics · Physics 2024-06-25 S. Mukherjee , S. R. Sitaram , X. Wang , S. Law

This paper summarises two recently developed techniques in power spectral analysis and their application to a sample of X-ray light curves of accreting collapsed objects in active galactic nuclei and X-ray binaries. The first technique is…

Astrophysics · Physics 2007-05-23 L. Stella , E. Arlandi , G. Tagliaferri , G. L. Israel

We describe a self calibrating optical technique that allows to perform absolute measurements of scattering cross sections for the light scattered at extremely small angles. Very good performances are obtained by using a very simple optical…

Optics · Physics 2009-11-10 Doriano Brogioli , Alberto Vailati , Marzio Giglio

This paper indicates that the sensitivity and accuracy of an infrared radiometer for emissivity measurements depends not only on its design and the measurement method, but also on the spurious radiation. This spurious radiation must be…

X-ray polarimetric measurements are based on studying the distribution of the directions of scattered photons or photoelectrons and on the search of a sinusoidal modulation with a period of {\pi}. We developed two tools for investigating…

Instrumentation and Methods for Astrophysics · Physics 2018-01-08 Enrico Massaro , Sergio Fabiani , Riccardo Campana , Enrico Costa , Ettore Del Monte , Fabio Muleri , Paolo Soffitta

The X-ray data around the North Ecliptic Pole (NEP) of the ROSAT All Sky Survey have been used to construct a contiguous area survey consisting of a sample of 445 individual X-ray sources above a flux of ~2x10^-14 erg cm^-2 s^-1 in the…

Astrophysics · Physics 2009-11-10 I. M. Gioia , J. P. Henry , C. R. Mullis , H. Bohringer , U. G. Briel , W. Voges , J. P. Huchra

The pepper-pot method is a widely used technique, originally proposed for measuring the emittance of space-charge-dominated electron beams from radio-frequency photoinjectors. With recent advances in producing high-brightness electron beams…

Accelerator Physics · Physics 2026-01-19 F. C. Salgado , A. Kozan , D. Seipt , D. Hollatz , P. Hilz , M. Kaluza , A. Sävert , A. Seidel , D. Ullmann , Y. Zhao , M. Zepf

A beam line is built after the IHEP RFQ for halo study. To determine transverse emittance and ellipse parameters of the RFQ output beam, beam size data obtained from the first two of 14 wire scanners are employed. By using the transfer…

X-ray polarimetry promises to give new information about high-energy astrophysical sources, such as binary black hole systems, micro-quasars, active galactic nuclei, and gamma-ray bursts. We designed, built and tested a hard X-ray…

In this paper we derive an exact full expression for the 2D probability distribution of the ellipticity of an object measured from data, only assuming Gaussian noise in pixel values. This is a generalisation of the probability distribution…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Massimo Viola , Thomas Kitching , Benjamin Joachimi

Weak lensing by large scale structure induces correlated ellipticities in the images of distant galaxies. The two-point correlation is determined by the matter power spectrum along the line of sight. We use the fully nonlinear evolution of…

Astrophysics · Physics 2009-10-28 Bhuvnesh Jain , Uros Seljak

The launch of the Nuclear Spectroscopic Telescope Array (NuSTAR) heralded a new era of sensitive high energy X-ray spectroscopy for X-ray binaries (XRBs). In this paper we show how multiple physical parameters can be measured from the…

High Energy Astrophysical Phenomena · Physics 2019-01-16 M. L. Parker , D. J. K. Buisson , J. A. Tomsick , A. C. Fabian , K. K. Madsen , D. J. Walton , F. Furst

An unbiased estimator for the ellipticity of an object in a noisy image is given in terms of the image moments. Three assumptions are made: i) the pixel noise is normally distributed, although with arbitrary covariance matrix, ii) the image…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-09 Nicolas Tessore

It is shown that the diffraction on a polycrystal can be used for investigation and diagnostics of X-ray radiation emitted in a forward direction by relativistic charged particles moving in crystalline or other targets or fields. Methods…

Instrumentation and Detectors · Physics 2025-03-07 Alexander V. Shchagin

The electronCT technique is an imaging method based on the multiple Coulomb scattering of relativistic electrons and has potential applications in medical and industrial imaging. It utilizes a pencil beam of electrons in the very high…

The soft X-ray band hosts a larger, more diverse range of variable sources than any other region of the electromagnetic spectrum. They are stars, compact binaries, SMBH's, the X-ray components of Gamma-Ray Bursts, their X-ray afterglows,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Paul Gorenstein

We have setup a simple field mapping measure system to describe graphically the 2D quasi-free-space electromagnetic wave in a parallel plate waveguide at the X-band frequencies. Our apparatus illustrates a potential application in…

Optics · Physics 2009-11-13 L. Zhao , X. Chen , C. K. Ong

In a previous paper, we reviewed theoretically some of the available processing schemes for X-ray wavefront sensing based on random modulation. We here show experimental applications of the technique for characterising both refractive and…

Instrumentation and Detectors · Physics 2020-02-24 Sebastien Berujon , Ruxandra Cojocaru , Pierre Piault , Rafael Celestre , Thomas Roth , Raymond Barrett , Eric Ziegler