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相关论文: Interstellar Seeing. I. Superresolution Techniques…

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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…

高能天体物理现象 · 物理学 2026-01-30 Dylan L. Jow , Delon Shen

To date, the search for radio technosignatures has focused on sky location as a primary discriminant between technosignature candidates and anthropogenic radio frequency interference (RFI). In this work, we investigate the possibility of…

天体物理仪器与方法 · 物理学 2023-07-19 Bryan Brzycki , Andrew P. V. Siemion , Imke de Pater , James M. Cordes , Vishal Gajjar , Brian Lacki , Sofia Sheikh

Comparing the asymmetry coefficients and scintillation indices for observed time variations of the intensity of the radiation of extragalactic sources and the predictions of theoretical models is a good test of the nature of the observed…

天体物理学 · 物理学 2009-11-11 V. I. Shishov , T. V. Smirnova , S. A. Tyul'bashev

Context. Interstellar scintillation (ISS) of pulsar emission can be used both as a probe of the ionised interstellar medium (IISM) and cause corruptions in pulsar timing experiments. Of particular interest are so-called scintillation arcs…

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…

天体物理仪器与方法 · 物理学 2024-02-06 Anna Tsai , Dylan L. Jow , Daniel Baker , Ue-Li Pen

We develop the theory of interstellar scintillation as caused by an irregular plasma having a power-law spatial density spectrum with a spectral exponent of 4 corresponding to a medium with abrupt changes in its density. An ``outer scale''…

天体物理学 · 物理学 2009-10-31 Hendrik Lambert , Barney Rickett

From 1979--1996 the Green Bank Interferometer was used by the Naval Research Laboratory to monitor the flux density from 146 compact radio sources at frequencies near 2 and 8 GHz. We filter the ``light curves'' to separate intrinsic…

天体物理学 · 物理学 2009-11-11 B. Rickett , T. J. W. Lazio , F. D. Ghigo

Observations over the last two decades have shown that a significant fraction of all flat-spectrum, extragalactic radio sources exhibit flux density variations on timescales of a day or less at frequencies of several GHz. It has been…

Intergalactic scintillation of distant quasars is sensitive to free electrons and therefore complements Ly$\alpha$ absorption line experiments probing the neutral intergalactic medium (IGM). We present a new scheme to compute IGM refractive…

宇宙学与河外天体物理 · 物理学 2015-06-16 A. Pallottini , A. Ferrara , C. Evoli

We present a fitting function to describe the statistics of flux modulations caused by interstellar scintillation. The function models a very general quantity: the cross-correlation of the flux observed from a compact radio source of finite…

天体物理学 · 物理学 2009-11-13 J. Goodman , R. Narayan

We derive the distribution of flux density of a compact source exhibiting strong diffractive scintillation. Our treatment accounts for arbitrary spectral averaging, spatially-extended source emission, and the possibility of intrinsic…

天体物理仪器与方法 · 物理学 2012-08-09 Michael D. Johnson , Carl R. Gwinn

Pulsars are the only cosmic radio sources known to be sufficiently compact to show diffractive interstellar scintillations. Images of the variance of radio signals in both time and frequency can be used to detect pulsars in large-scale…

天体物理仪器与方法 · 物理学 2016-08-17 S. Dai , S. Johnston , M. E. Bell , W. A. Coles , G. Hobbs , R. D. Ekers , E. Lenc

Most of the baryons in the low-redshift universe reside in a warm/hot component which is difficult to detect with standard absorption/emission line techniques. We propose to use quasar refractive scintillation as an useful, complementary…

天体物理学 · 物理学 2009-11-06 Andrea Ferrara , Rosalba Perna

We demostrate that the measurement of fluctuations of polarization due to the galactic interstellar scintillations may be used to study the structure of the radiation field at compact radio sources. We develop a mathematical formalism and…

天体物理学 · 物理学 2009-10-31 Mikhail V. Medvedev

A new method for separating intensity variations of a source's radio emission having various physical natures is proposed. The method is based on a joint analysis of the structure function of the intensity variations and the asymmetry…

天体物理学 · 物理学 2009-11-11 V. I. Shishov , T. V. Smirnova

Stars twinkle because their light propagates through the atmosphere. The same phenomenon is expected on a longer time scale when the light of remote stars crosses an interstellar turbulent molecular cloud, but it has never been observed at…

天体物理仪器与方法 · 物理学 2015-06-12 Farhang Habibi , Marc Moniez , Reza Ansari , Sohrab Rahvar

The observed interstellar scintillation pattern of an intra-day variable radio source is influenced by its source structure. If the velocity of the interstellar medium responsible for the scattering is comparable to the earth's, the vector…

天体物理学 · 物理学 2009-11-07 J-P Macquart , D. L. Jauncey

We propose a new method to detect off-pulse (unpulsed and/or continuous) emission from pulsars, using the intensity modulations associated with interstellar scintillation. Our technique involves obtaining the dynamic spectra, separately for…

高能天体物理现象 · 物理学 2018-05-23 Kumar Ravi , Avinash A. Deshpande

The propagation of radio waves from distant compact radio sources through turbulent interstellar plasma in our Galaxy causes these sources to twinkle, a phenomenon called interstellar scintillation. Such scintillations are a unique probe of…

Scintillation noise due to the Earth's turbulent atmosphere can be a dominant noise source in high-precision astronomical photometry when observing bright targets from the ground. Here we describe the phenomenon of scintillation from its…

天体物理仪器与方法 · 物理学 2015-08-06 J. Osborn , D. Föhring , V. S. Dhillon , R. W. Wilson
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