English
Related papers

Related papers: The stellar scintillation on large and extremely l…

200 papers

We present an analysis of rotation measure (RM) fluctuations from the Test Region of the Southern Galactic Plane Survey (SGPS), along with emission measure (EM) fluctuations in the same field taken from the Southern H-Alpha Sky Survey…

The turbulence induced decay of orbital angular momentum (OAM) entanglement between two photons is investigated numerically and experimentally. To compare our results with previous work, we simulate the turbulent atmosphere with a single…

Quantum Physics · Physics 2015-06-16 Alpha Hamadou Ibrahim , Filippus S. Roux , Melanie McLaren , Thomas Konrad , Andrew Forbes

Analyzing data from GLAST's Large Area Telescope (LAT) will require sophisticated techniques. The PSF and effective area are functions of both photon energy and the position in the field-of-view. During most of the mission the observatory…

Astrophysics · Physics 2009-11-10 David L. Band , Seth W. Digel , the GLAST LAT Collaboration , the GSSC

In this paper we calculate the delay of the arrival times of visible photons on the focal plane of a telescope and its fluctuations as function of local atmospheric conditions (temperature, pressure, chemical composition, seeing values) and…

Instrumentation and Methods for Astrophysics · Physics 2011-12-16 Stefano Cavazzani Sergio Ortolani , Cesare Barbieri

It is proposed to search for scintillation of extragalactic sources through the last unknown baryonic structures. Appropriate observation of the scintillation process described here should allow one to detect column density stochastic…

Astrophysics · Physics 2007-05-23 Marc Moniez

We investigate turbulent gas motions in spiral galaxies and their importance to star formation in far outer disks, where the column density is typically far below the critical value for spontaneous gravitational collapse. Following the…

Astrophysics of Galaxies · Physics 2017-02-22 Erin Maier , Li-Hsin Chien , Deidre A. Hunter

The daily variation of the solar photocenter over some 11 years is derived from the Mount Wilson data reprocessed by Ulrich et al. 2010 to closely match the surface distribution of solar irradiance. The standard deviations of astrometric…

Solar and Stellar Astrophysics · Physics 2015-05-19 V. V. Makarov , D. Parker , R. K. Ulrich

We study the low-energy two-body scattering in optical lattices with all higher-band effects included in an effective potential, using a renormalization group approach. As the potential depth reaches a certain value, a resonance of low…

Quantum Gases · Physics 2010-04-22 Xiaoling Cui , Yupeng Wang , Fei Zhou

The characteristic outer scale of turbulence and the ratio of the random to ordered components of the magnetic field are key parameters to characterise magnetic turbulence in the interstellar gas, which affects the propagation of cosmic…

We derive limits for wave optics simulations of plane wave propagation in non-Kolmogorov turbulence using the split-step method and thin phase screens. These limits are used to inform two simulation campaigns where the relationship between…

Optics · Physics 2023-01-18 Jeremy P. Bos , Stephen Grulke , Jeff Beck

Ground-based thermal infrared observations face substantial challenges in correcting the predominant background emitted as thermal radiation from the atmosphere and the telescope itself. With the upcoming 40\,m class ELTs, unprecedented…

Instrumentation and Methods for Astrophysics · Physics 2024-08-29 J. R. Sauter , W. Brandner , J. Heidt , F. Cantalloube

Bright single and binary stars were observed at the 4.1-m telescope with a fast electron-multiplication camera in the regime of partial turbulence correction by the visible-light adaptive optics system. We compare the angular resolution…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 A. Tokovinin , R. Cantarutti , R. Tighe , P. Schurter , N. van der Bliek , M. Martinez , E. Mondaca

We propose a novel means of directly measuring cosmological distances using scintillated microlensing of fast radio bursts (FRBs). In standard strong lensing measurements of cosmic expansion, the main source of systematic uncertainty lies…

Instrumentation and Methods for Astrophysics · Physics 2024-02-06 Anna Tsai , Dylan L. Jow , Daniel Baker , Ue-Li Pen

At Paranal Observatory, the least predictable parameter affecting the short-term scheduling of astronomical observations is the optical turbulence, especially the seeing, coherence time and ground layer fraction. These are critical…

Instrumentation and Methods for Astrophysics · Physics 2019-10-31 J. Milli , R. Gonzalez , P. R. Fluxa , A. Chacon , J. Navarette , M. Sarazin , E. Pena , R. Carrasco-Davis , A. Solarz , J. Smoker , C. Martayan , C. Melo , E. Sedaghati , S. Mieske , O. Hainaut , L. Tacconi-Garman

The advent of Extremely Large Telescopes ELTs, ground-based optical or infrared observatories with primary mirrors exceeding 20 m heralds a transformative epoch in observational astronomy. This article examines the dawn of this new era and…

Popular Physics · Physics 2026-05-22 Priya Hasan

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

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

We report on the simultaneous Giant Metrewave Radio Telescope (GMRT) and Algonquin Radio Observatory (ARO) observations at 550-750 MHz of the scintillation of PSR B1508+55, resulting in a $\sim$10,000-km baseline. This regime of measurement…

High Energy Astrophysical Phenomena · Physics 2021-08-18 V. R. Marthi , D. Simard , R. A. Main , U. -L. Pen , M. H. van Kerkwijk , K. Vanderlinde , Y. Gupta , C. Roberts , B. M. Quine

Microturbulence, i.e. enhanced fluctuations of plasma density, electric and magnetic fields, is of great interest in astrophysical plasmas, but occurs on spatial scales far too small to resolve by remote sensing, e.g., at ~ 1-100 cm in the…

Astrophysics · Physics 2009-11-13 Gelu M. Nita , Dale E. Gary , Gregory D. Fleishman