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Related papers: Simulation of optical interstellar scintillation

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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…

High Energy Astrophysical Phenomena · Physics 2018-05-23 Kumar Ravi , Avinash A. Deshpande

Our ability to predict the structure and evolution of stars is in part limited by complex, 3D hydrodynamic processes such as convective boundary mixing. Hydrodynamic simulations help us understand the dynamics of stellar convection and…

Most detected neutral atomic hydrogen (HI) at low redshift is associated with optically bright galaxies. However, a handful of HI clouds are known which appear to be optically dark and have no nearby potential progenitor galaxies, making…

Astrophysics of Galaxies · Physics 2018-05-23 Rhys Taylor , Richard Wünsch , Jan Palouš

We have investigated the degree to which turbulence in the Very Local Interstellar Clouds resembles the highly-studied turbulence in the solar corona and the solar wind. The turbulence diagnostics for the Local Clouds are the absorption…

Astrophysics of Galaxies · Physics 2015-05-28 Steven R. Spangler , Allison H. Savage , Seth Redfield

We review progress in numerical simulations of star cluster formation. These simulations involve the bottom-up assembly of clusters through hierarchical mergers, which produces a fractal stellar distribution at young (~0.5 Myr) ages. The…

Astrophysics of Galaxies · Physics 2015-05-14 Cathie Clarke

Stellar intensity interferometers will achieve stellar imaging with a tenth of a milli- arcsecond resolution in the optical band by taking advantage of the large light collect- ing area and broad range of inter-telescope distances offered…

Instrumentation and Methods for Astrophysics · Physics 2013-03-19 Janvida Rou , Paul D. Nuñez , David Kieda , Stephan LeBohec

Atmospheric turbulence is an important limit to high angular resolution in astronomy. Interferometry resolved this issue by filtering the incoming light with single-mode fibers. Thanks to this technique, we obtained with the IOTA…

Instrumentation and Methods for Astrophysics · Physics 2010-03-18 Sylvestre Lacour

Understanding the properties of interstellar turbulence is a great intellectual challenge and the urge to solve this problem is partially motivated by a necessity to explain the star formation mystery. This review deals with a recently…

Astrophysics · Physics 2007-05-23 A. Lazarian

A large fraction of cool, low-mass stars exhibit brightness fluctuations that arise from a combination of convective granulation, acoustic oscillations, magnetic activity, and stellar rotation. Much of the short-timescale variability takes…

Solar and Stellar Astrophysics · Physics 2015-06-18 Steven R. Cranmer , Fabienne A. Bastien , Keivan G. Stassun , Steven H. Saar

Density fluctuations in the ionised interstellar medium have a profound effect on radio pulsar observations, through angular scattering, intensity scintillations, and small changes in time delays from dispersion. Here we show that it is…

High Energy Astrophysical Phenomena · Physics 2023-04-12 Daniel J. Reardon , William A. Coles

Transport of intensity equation (TIE) exhibits a non-interferometric correlation between intensity and phase variations of intermediate fields (e.g., light and electron) in biological imaging. Previous TIE formulations have generally…

Biological Physics · Physics 2023-07-17 Masaki Watabe , Yasuhiro Hirano , Atsuko Iwane , Osamu Matoba , Koichi Takahashi

It is known that stellar differential rotation can be detected by analyzing the Fourier transform of spectral line profiles, since the ratio of the 1st- and 2nd-zero frequencies is a useful indicator. This approach essentially relies on the…

Solar and Stellar Astrophysics · Physics 2020-02-19 Yoichi Takeda

A physical model and two-dimensional numerical method for computing the evolution and spectra of protostellar clouds are described. The physical model is based on a system of magneto-gasdynamical equations, including ohmic and ambipolar…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. G. Zhilkin , Ya. N. Pavlyuchenkov , S. N. Zamozdra

Molecular clouds are observed to be turbulent, but the origin of this turbulence is not well understood. As a result, there are two different approaches to simulating molecular clouds, one in which the turbulence is allowed to decay after…

Astrophysics · Physics 2009-11-13 Stella S. R. Offner , Richard I. Klein , Christopher F. McKee

Quasi-continuous observations of PSR B03239+54 over 20 days using the Nanshan 25-m telescope at 1540 MHz have been used to study the effects of refractive scintillation on the pulsar flux density and diffractive scintillation properties.…

Astrophysics · Physics 2009-11-13 N. Wang , Z. Yan , R. N. Manchester , H. X. Wang

We derive an analytic prediction for the star formation rate in environments ranging from normal galactic disks to starbursts and ULIRGs in terms of the observables of those systems. Our calculation is based on three premises: (1) star…

Astrophysics · Physics 2010-04-06 Mark R. Krumholz , Christopher F. McKee

We analytically and numerically study the temporal intensity pattern emerging from the linear or nonlinear evolutions of a single or double phase jump in an optical fiber. The results are interpreted in terms of interferences of the…

Optics · Physics 2020-07-07 Anastasiia Sheveleva , Christophe Finot

A subset of magnetic stars exhibit periodic radio pulses produced by the coherent electron cyclotron maser mechanism. These pulses are known to exhibit both temporal and spectral variations, which have been attributed to phenomena intrinsic…

Solar and Stellar Astrophysics · Physics 2026-04-21 J. S. Morgan , B. Das , H. E. Bignall

Extreme scattering events (ESEs) in the interstellar medium (ISM) were first observed in regular flux measurements of compact extragalactic sources. They are characterized by a flux variation over a period of weeks, suggesting the passage…

Previous simulation studies by Menzel et al. [Phys. Rev. X 10, 021002 (2020)] have shown that scattering patterns of light transmitted through artificial nerve fiber constellations contain valuable information about the tissue substructure…

Medical Physics · Physics 2020-07-30 Miriam Menzel , Silvania F. Pereira
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