English
Related papers

Related papers: Conjugate-plane photometry: Reducing scintillation…

200 papers

To detect Earth-like planets in the visible with a coronagraphic telescope, two major noise sources have to be overcome: the photon noise of the diffracted star light, and the speckle noise due to the star light scattered by instrumental…

In adaptive optics, the tracker and wavefront sensor commonly measure irradiance centroids (in their respective focal planes) to estimate the turbulence-degraded wavefront in the pupil plane. Several factors affect the accuracy of these…

Optics · Physics 2025-05-02 Milo W. Hyde , Eric W. Mitchell , Mark F. Spencer

Observations across the electromagnetic spectrum of radiative processes involving interstellar dust -- emission, extinction, and scattering -- are used to constrain the parameters of dust models and more directly to aid in foreground…

Current cosmological analyses which use Type Ia supernova (SN Ia) observations combine SN samples to expand the redshift range beyond that of a single sample and increase the overall sample size. The inhomogeneous photometric calibration…

Speckle Noise is the dominant source of error in high contrast imaging with adaptive optics system. We discuss the potential for wavefront sensing telemetry to calibrate speckle noise with sufficient precision and accuracy so that it can be…

Pulsar scintillation observations have revealed ubiquitous discrete scintillation screens in the interstellar medium. A major obstacle in identifying the nature of these screens is the uncertainty in their distances, which prevents precise…

Astrophysics of Galaxies · Physics 2026-01-26 Yuanshang Huang , Xun Shi , Jumei Yao , Weiwei Zhu , Yonghua Xu

We discuss several improvements in the detection of atmospheric turbulence using SLOpe Detection And Ranging (SLODAR). Frequently, SLODAR observations have shown strong ground-layer turbulence, which is beneficial to adaptive optics. We…

Astrophysics · Physics 2009-11-13 Michael Goodwin , Charles Jenkins , Andrew Lambert

Compact radio sources such as pulsars and FRBs undergo scintillation in the interstellar medium (ISM) when scattered images interfere at the observer. ``Scintillometry'' refers to the range of techniques to extract astrometric information…

High Energy Astrophysical Phenomena · Physics 2026-01-30 Dylan L. Jow , Delon Shen

Scintillating homogeneous detectors represent the state of the art in electromagnetic calorimetry. Moreover, the currently neglected crystalline nature of the most common inorganic scintillators can be exploited to achieve an outstanding…

The speckle imaging is a photographic technique that resolves objects viewed through severely distorted media. The results are insensitive to the errors caused by apparent size of the isoplanatic patch and the telescope aberrations. In this…

Astrophysics · Physics 2007-05-23 S K Saha

For many pulsars, the scattering structures responsible for scintillation are typically dominated by a single, thin screen along the line of sight, which persists for years or decades. In recent years, an increasing number of doubly-lensed…

Astrophysics of Galaxies · Physics 2025-02-11 Yen-Hua Chen , Samuel Siegel , Daniel Baker , Ue-Li Pen , Dan Stinebring

The simple 3-D radiative transfer model in the atmosphere of the Earth is built for numerical comparison of direct solar radiation and limb scattering background at the definite layer during the deep twilight period at the middle and upper…

Atmospheric and Oceanic Physics · Physics 2025-09-05 Oleg S. Ugolnikov

Quasi-static speckles are a current limitation to faint companion imaging of bright stars. Here we show through simulation and theory that an adaptive pupil mask can be used to reduce these speckles and increase the visibility of faint…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 James Osborn

The image quality budget of many telescopes can have substantial contributions from local seeing, both``mirror'' and ``dome'', which arise from turbulence and temperature variations that are difficult to quantify, measure directly, and…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Christopher W. Stubbs

We propose an improved method for the atmospheric extinction reduction within optical photometry. Our method is based on the simultaneous multicolor observations of photometric standards. Such data are now available within the modern…

Instrumentation and Methods for Astrophysics · Physics 2015-10-06 A. Zakharov , A. Mironov , A. Biryukov , N. Kroussanova , M. Prokhorov , G. Beskin , S. Karpov , S. Bondar , E. Ivanov , A. Perkov , V. Sasyuk

A distribution function approach is applied to describe the dynamics of the laser beam in the Earth atmosphere. Using a formal solution of the kinetic equation for the distribution function, we have developed an iterative scheme for…

Quantum Physics · Physics 2016-03-23 Oleksandr O. Chumak , Roman A. Baskov

WL measurements have well-known shear estimation biases, which can be partially corrected for with the use of image simulations. We present an analysis of simulated images that mimic HST/ACS observations of high-redshift galaxy clusters,…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-26 B. Hernandez-Martin , T. Schrabback , H. Hoekstra , N. Martinet , J. Hlavacek-Larrondo , L. E. Bleem , M. D. Gladders , B. Stalder , A. A. Stark , M. Bayliss

We have carried out photometric follow-up observations of bright transiting extrasolar planets using the CbNUOJ 0.6m telescope. We have tested the possibility of obtaining high photometric precision by applying the telescope defocus…

Solar and Stellar Astrophysics · Physics 2015-06-24 Tobias C. Hinse , Wonyong Han , Jo-Na Yoon , Chung-Uk Lee , Yong-Gi Kim , Chun-Hwey Kim

Currently operating optical superconducting tunnel junction (STJ) detectors, developed in ESA, can simultaneously measure the wavelength (delta lambda = 50 nm at 500 nm) and arrival time (to within ~5 micros) of individual photons in the…

In many astrophysical systems, smoothly-varying large-scale variations coexist with small-scale fluctuations. For example, a large-scale velocity or density gradient can exist in molecular clouds that exhibit small-scale turbulence. In…

Instrumentation and Methods for Astrophysics · Physics 2017-10-20 Jungyeon Cho
‹ Prev 1 4 5 6 7 8 10 Next ›