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Related papers: Density Fluctuations in a Polar Coronal Hole

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Intermittency has been studied extensively in the fast and slow solar winds but to a far lesser extent in interplanetary coronal mass ejections (ICMEs). While ICMEs are often characterized by their relatively smooth, large-scale magnetic…

Solar and Stellar Astrophysics · Physics 2025-07-08 Julia Ruohotie , Simon Good , Christian Möstl , Emilia Kilpua

We present coronal density profiles derived from low-frequency (80-240 MHz) imaging of three type III solar radio bursts observed at the limb by the Murchison Widefield Array (MWA). Each event is associated with a white light streamer at…

Solar and Stellar Astrophysics · Physics 2018-10-17 Patrick I. McCauley , Iver H. Cairns , John Morgan

Alfv\'enic waves are known to be prevalent throughout the corona and solar wind. Determining the Poynting flux supplied by the waves is required for constraining their role in plasma heating and acceleration, as well as providing a…

Solar and Stellar Astrophysics · Physics 2025-01-24 Richard J. Morton , Micah J. Weberg , N. Balodhi , James A. McLaughlin

We examine the dynamical behavior of white light polar plume structures in the inner corona that are observed from the ground during total solar eclipses, based on their EUV hot and cool emission line counterparts observed from space. EUV…

Solar and Stellar Astrophysics · Physics 2018-10-17 E. Tavabi , S. Koutchmy , L. Golub

It has been suggested that under solar coronal conditions, drift waves may contribute to coronal heating. Specific properties of the drift waves to be expected in the solar corona have, however, not yet been determined using more advanced…

Solar and Stellar Astrophysics · Physics 2024-08-14 Michaela Brchnelova , MJ Pueschel , Stefaan Poedts

We combine results from deep ALMA observations of massive ($M_*>10^{10}\;M_{\odot}$) galaxies at different redshifts to show that the column density of their inter stellar medium (ISM) rapidly increases towards early cosmic epochs. Our…

Sun-as-a-star coronal plasma composition, derived from full-Sun spectra, and the F10.7 radio flux (2.8 GHz) have been shown to be highly correlated (r = 0.88) during solar cycle 24. However, this correlation becomes nonlinear during…

We propose a method to determine the power spectrum of \HI column density fluctuations using radio-interferometric observations of 21-cm emission from the ISM of galaxies. We have used this to estimate the power spectra of six nearly face…

Astrophysics of Galaxies · Physics 2015-06-16 Prasun Dutta , Somnath Bharadwaj

Slow magnetosonic waves associated with flares were observed in coronal loops by SOHO/SUMER, SDO/AIA in various EUV bandpasses, and other instruments. The excitation and damping of slow magnetosonic waves provides information on the…

Solar and Stellar Astrophysics · Physics 2022-02-23 Leon Ofman , Tongjiang Wang

While previous work explored the fractality and self-organized criticality (SOC) of flares and nanoflares in wavelengths emitted in the solar corona (such as in hard X-rays, soft X-rays, and EUV wavelenghts), we focus here on impulsive…

Solar and Stellar Astrophysics · Physics 2022-07-27 Markus J. Aschwanden , Nived Vilangot Nhalil

The intensity of the \oiv~2s$^{2}$ 2p $^{2}$P-2s2p$^{2}$ $^{4}$P and \siv~3 s$^{2}$ 3p $^{2}$P- 3s 3p$^{2}$ $^{4}$ P intercombination lines around 1400~\AA~observed with the \textit{Interface Region Imaging Spectrograph} (IRIS) provide a…

Solar and Stellar Astrophysics · Physics 2016-10-19 V. Polito , G. Del Zanna , J. Dudík , H. E. Mason , A. Giunta , K. K. Reeves

Cluster abundance measurements are among the most sensitive probes of the amplitude of matter fluctuations in the universe, which in turn can help constrain other cosmological parameters, like the dark energy equation of state or neutrino…

Astrophysics · Physics 2010-10-27 Rachel Mandelbaum , Uros Seljak

Coronal loops act as resonant cavities for low frequency fluctuations that are transmitted from the deeper layers of the solar atmosphere and are amplified in the corona, triggering nonlinear interactions. However trapping is not perfect,…

Solar and Stellar Astrophysics · Physics 2015-06-03 Andrea Verdini , Roland Grappin , Marco Velli

Across a large range of scales, accreting sources show remarkably similar patterns of variability, most notably the log-normality of the luminosity distribution and the linear root-mean square (rms)-flux relationship. These results are…

High Energy Astrophysical Phenomena · Physics 2024-01-30 Samuel G. D. Turner , Christopher S. Reynolds

We explore the effect of an inhomogeneous mass density field on frequencies and wave profiles of torsional Alfven oscillations in solar coronal loops. Dispersion relations for torsional oscillations are derived analytically in limits of…

Astrophysics · Physics 2019-08-19 T. V. Zaqarashvili , K Murawski

The tandem mirror GAMMA 10 utilizes an electron cyclotron resonance heating (ECRH) for forming a confinement potential. Density fluctuation is observed using microwaves, such as interferometer, reflectometry and Fraunhofer diffraction (FD)…

Plasma Physics · Physics 2007-05-23 A. Itakura , S. Tsunoda , M. Fukuhara , H. Higaki , H. Hojo , M. Ichimura , K. Ishii , Y. Shima , H. Takiue , M. Yoshikawa , T. Cho

We demonstrate that measurements of atom-number fluctuations in a trapped dipolar condensate can reveal the presence of the elusive roton excitation. The key signature is a super-Poissonian peak in the fluctuations as the size of the…

Quantum Gases · Physics 2013-06-28 R. N. Bisset , P. B. Blakie

We report observations of solar spicules at millimeter wavelengths (mm-$\lambda$) using the Atacama Large Millimeter/submillimeter Array (ALMA). These are supplemented by observations in optical (O), ultraviolet (UV) and extreme ultraviolet…

Solar and Stellar Astrophysics · Physics 2025-04-09 T. S. Bastian , C. Alissandrakis , A. Nindos , M. Shimojo , S. M. White

Galaxy clustering provides a powerful way to probe cosmology. This requires understanding of the background mean density of galaxy samples, which is estimated from the survey itself by averaging the observed galaxy number density over the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-30 Jaiyul Yoo , Daniel Eisenstein