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Related papers: The ROSAT HRI Point Spread Function

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Current measurements of the weak lensing signal induced by large scale structure provide useful constraints on a range of cosmological parameters. However, the ultimate succes of this technique depends on the accuracy with which one can…

Astrophysics · Physics 2009-11-07 Henk Hoekstra

Published analyses of very long baseline interferometry (VLBI) data for the sources included in the third International Celestial Reference Frame (ICRF3) catalog have revealed object-specific, excess astrometric variability and…

Astrophysics of Galaxies · Physics 2024-11-27 Valeri V. Makarov , Phil Cigan , David Gordon , Megan C. Johnson , Christopher DiLullo , Sébastien Lambert

We present results of a study of the localization capability of Fermi-LAT, using a large set of blazars with precise radio locations. Since the width of the PSF decreases with energy, the performance is typically dominated by a few high…

High Energy Astrophysical Phenomena · Physics 2009-12-22 T. H. Burnett , M. Kerr , M. Roth

Ultrasound is widely used in medical diagnostics allowing for accessible and powerful imaging but suffers from resolution limitations due to diffraction and the finite aperture of the imaging system, which restricts diagnostic use. The…

Computer Vision and Pattern Recognition · Computer Science 2024-08-08 Felix Duelmer , Walter Simson , Mohammad Farid Azampour , Magdalena Wysocki , Angelos Karlas , Nassir Navab

The MRS is one of the four observing modes of JWST/MIRI. Using JWST in-flight data of unresolved (point) sources, we can derive the MRS absolute spectral response function (ASRF) starting from raw data. Spectral fringing plays a critical…

Previous studies determining which astronomical photometry software is best suited for a particular dataset are usually focused on speed, source classification, and/or meeting a sensitivity requirement. For faint objects in particular, the…

Instrumentation and Methods for Astrophysics · Physics 2013-05-27 Sarah Sonnett , Karen Meech , Robert Jedicke , Schelte Bus , John Tonry , Olivier Hainaut

Synthetic aperture sonar (SAS) image resolution is constrained by waveform bandwidth and array geometry. Specifically, the waveform bandwidth determines a point spread function (PSF) that blurs the locations of point scatterers in the…

Computer Vision and Pattern Recognition · Computer Science 2021-12-17 Albert Reed , Thomas Blanford , Daniel C. Brown , Suren Jayasuriya

Astrophysical sources such as radio halos and relics in galaxy clusters, supernova remnants and radio galaxies have angular sizes from a few to several $10$s of arcminutes. In radio interferometric imaging of such sources, the largest…

Instrumentation and Methods for Astrophysics · Physics 2017-09-13 Deepak Kumar Deo , Ruta Kale

In collaboration with the Observatories of Palermo and Rome and the SAX-SDC we are constructing a multi-site interactive archive system featuring specific analysis tools. In this context we developed a detection algorithm based on the…

Point spread function (PSF) engineering of the emitter can code higher spatial frequency information of an image to break diffraction limit but suffer from the complexed optical systems. Here we present a robust strategy to simultaneously…

Optics · Physics 2021-02-23 Chaohao Chen , Baolei Liu , Yongtao Liu , Jiayan Liao , Xuchen Shan , Fan Wang , Dayong Jin

This study presents a comprehensive end-to-end simulation analysis of the optical imaging performance of the China Survey Space Telescope (CSST) under in-orbit conditions. An integrated system model incorporating five static and two dynamic…

Instrumentation and Methods for Astrophysics · Physics 2025-11-11 Zhang Ban , Xiao-Bo Li , Xun Yang , Yu-Xi Jiang , Hong-Cai Ma , Wei Wang , Jin-guang Lv , Cheng-Liang Wei , De-Zi Liu , Guo-Liang Li , Chao Liu , Nan Li , Ran Li , Peng Wei

This paper investigates the capabilities and effectiveness of backward localization centered on reconfigurable intelligent surfaces (RISs). In the backward sensing paradigm, the region of interest (RoI) is illuminated using a set of diverse…

Signal Processing · Electrical Eng. & Systems 2025-12-15 Fuhai Wang , Tiebin Mi , Chun Wang , Rujing Xiong , Zhengyu Wang , Robert Caiming Qiu

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 develop a new method to estimate gravitational shear by adopting an elliptical weight function to measure background galaxy images. In doing so, we introduce a new concept of "zero plane" which is an imaginal source plane where shapes of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Yuki Okura , Toshifumi Futamase

In order to enhance accuracy of astrophysical estimates obtained on Adaptive-optics (AO) images, such as photometry and astrometry, we investigate a new concept to constrain the Point Spread Function (PSF) model called PSF Reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-06-26 O. Beltramo-Martin , C. M. Correia , S. Ragland , L. Jolissaint , B. Neichel , T. Fusco , P. L. Wizinowich

As part of the astrometric Hubble Space Telescope (HST) large program GO-12911, we conduct an in-depth study to characterize the point spread function (PSF) of the Uv-VISual channel (UVIS) of the Wide Field Camera 3 (WFC3), as a necessary…

Instrumentation and Methods for Astrophysics · Physics 2017-07-05 J. Anderson , L. R. Bedin

The spatial resolution of astronomical images is limited by atmospheric turbulence and diffraction in the telescope optics, resulting in blurred images. This makes it difficult to accurately measure the brightness of blended objects because…

Instrumentation and Methods for Astrophysics · Physics 2023-05-31 Kevin Michalewicz , Martin Millon , Frédéric Dux , Frédéric Courbin

Context: in astronomy, observing large fractions of the sky within a reasonable amount of time implies using large field-of-view (fov) optical instruments that typically have a spatially varying Point Spread Function (PSF). Depending on the…

Computer Vision and Pattern Recognition · Computer Science 2017-03-20 F. M. Ngolè Mboula , J. -L. Starck

Rotating-PSF imaging via spiral phase engineering can localize point sources over large focal depths in a snapshot mode. This letter presents a full vector-field analysis of the rotating-PSF imager that quantifies the PSF signature of the…

Optics · Physics 2014-12-22 Zhixian Yu , Sudhakar Prasad

About 200 X-ray sources from a sample of spectrally hard ROSAT PSPC sources, given in the catalog of Haberl & Pietsch (1999), and observed in a ~60 square degree field of the LMC during several archival pointed observations with a wide…

Astrophysics · Physics 2009-11-07 P. Kahabka
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