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Related papers: Macro-microturbulence in the solar photosphere

200 papers

The rotation curve is significant to research on dark matter and the structure of the Milky Way. But it is a great challenge to measure rotation curve accurately, and different ways obtain distinct results. In this work, we use a DIY small…

Astrophysics of Galaxies · Physics 2024-04-30 Hong-Yu Li , Jia-Hao Hu

The self-correlation level contours at the 1010 cm scale reveal a 3D isotropic feature in the slow solar wind and a quasi-anisotropic feature in the fast solar wind. However, the 1010 cm scale is approximately near the lowfrequency break…

Space Physics · Physics 2019-12-18 Honghong Wu , Chuanyi Tu , Xin Wang , Jiansen He , Linghua Wang

The effects of turbulence on the mixing of gases and dust in the outer Solar nebula are examined using 3-D MHD calculations in the shearing-box approximation with vertical stratification. The turbulence is driven by the magneto-rotational…

Astrophysics · Physics 2009-11-13 N. J. Turner , K. Willacy , G. Bryden , H. W. Yorke

We confirm, quantify, and provide a table of the coherent velocity substructure of the Milky Way disk within 2 kpc of the Sun towards the Galactic anticenter, with 0.2 kpc resolution. We use the radial velocities of ~340,000 F-type stars…

Astrophysics of Galaxies · Physics 2017-10-11 Alan N. Pearl , Heidi Jo Newberg , Jeffrey L. Carlin , R. Fiona Smith

The first two orbits of the Parker Solar Probe (PSP) spacecraft have enabled the first in situ measurements of the solar wind down to a heliocentric distance of 0.17 au (or 36 Rs). Here, we present an analysis of this data to study solar…

Instabilities and turbulence extending to the smallest dynamical scales play important roles in the deposition of energy and momentum by gravity waves throughout the atmosphere. However, these dynamics and their effects have been impossible…

Instrumentation and Methods for Astrophysics · Physics 2015-10-08 A. D. Miller , D. C. Fritts , D. Chapman , G. Jones , M. Limon , D. Araujo , J. Didier , S. Hillbrand , C. B. Kjellstrand , A. Korotkov , G. Tucker , Y. Vinokurov , K. Wan , L. Wang

Paper I presents the magnetic structure of a filament that developed in active region (AR) NOAA 10781. In this paper we complement those results with the velocities retrieved from Doppler shifts measured at the chromosphere and the…

Solar and Stellar Astrophysics · Physics 2014-01-14 C. Kuckein , V. Martinez Pillet , R. Centeno

We report a chromospheric jet lasting for more than 1 hr observed by Hinode Solar Optical Telescope in unprecedented detail. The ejection occurred in three episodes separated by 12-14 min, with the amount and velocity of material decreasing…

Solar and Stellar Astrophysics · Physics 2012-08-17 Wei Liu , Thomas E. Berger , Alan M. Title , Theodore D. Tarbell

We present radial velocities for 2045 stars in the Small Magellanic Cloud (SMC), obtained from the 2dF survey by Evans et al. (2004). The great majority of these stars are of OBA type, tracing the dynamics of the young stellar population.…

Astrophysics · Physics 2014-11-18 Christopher J. Evans , Ian D. Howarth

The motions of small-scale magnetic flux elements in the solar photosphere can provide some measure of the Lagrangian properties of the convective flow. Measurements of these motions have been critical in estimating the turbulent diffusion…

Solar and Stellar Astrophysics · Physics 2018-02-27 Piyush Agrawal , Mark P. Rast , Milan Gosic , Luis R. Bellot Rubio , Matthias Rempel

Guided by the duality of turbulence (random versus coherent we seek coherent structures in the turbulent velocity field of molecular clouds, anticipating their importance in cloud evolution. We analyse a large map (40' by 20') obtained with…

Astrophysics of Galaxies · Physics 2015-05-13 Pierre Hily-Blant , Edith Falgarone

Using turbulent MHD simulations (magnetic Reynolds numbers up to 8000) and Hinode observations, we study effects of turbulence on measuring the solar magnetic field outside active regions. Firstly, from synthetic Stokes V profiles for the…

Astrophysics · Physics 2011-02-11 Jonathan Pietarila Graham , Sanja Danilovic , Manfred Schuessler

We measure the Galactic rotation curve and its first two vertical derivatives in the first and fourth quadrants of the Milky Way using the 21 cm VGPS and SGPS. We find tangent velocities of the atomic gas as a function of galactic longitude…

Astrophysics · Physics 2009-06-23 E. S. Levine , Carl Heiles , Leo Blitz

This paper reports results on the statistical analysis of HI turbulence in the Small Magellanic Cloud (SMC). We use 21 cm channel maps, obtained with the Australia Telescope Compact Array and the Parkes telescope, and analyze the spectrum…

Astrophysics · Physics 2016-08-16 S. Stanimirović , A. Lazarian

This paper provides two families of flexible and simple galaxy models. Representatives of many of the families possess the important cosmological cusps, with the density behaving like 1/r or 1/r^1.33 or 1/r^1.5 at small radii. The density…

Astrophysics · Physics 2007-05-23 J. H. an , N. W. Evans

Magnetic flux is continuously being removed and replenished on the solar surface. To understand the removal process we carried out 3D radiative MHD simulations of the evolution of patches of photospheric magnetic field with equal amounts of…

Solar and Stellar Astrophysics · Physics 2015-05-30 Robert Cameron , Alexander Voegler , Manfred Schuessler

The scaling anisotropy is crucial to interpret the nonlinear interactions in solar wind turbulence. Previous observations provide diverse results and the structure function analyses are also reported to be an approach to investigate the…

Space Physics · Physics 2020-11-23 Honghong Wu , Chuanyi Tu , Xin Wang , Jiansen He , Liping Yang , Linghua Wang

Intermittency and anisotropy are two important aspects of plasma turbulence, which the solar wind provides a natural laboratory to investigate. However, their forms and nature are still under debate, making it difficult to achieve a…

Solar and Stellar Astrophysics · Physics 2025-05-21 Honghong Wu , Jiansen He , Liping Yang , Xin Wang , Shiyong Huang , Zhigang Yuan

Photospheric waves in sunspots moving radially outwards at speeds faster than the characteristic wave velocities have been recently detected. It has been suggested that they are the visual pattern of $p-$modes excited around 5 Mm beneath…

Solar and Stellar Astrophysics · Physics 2017-02-22 T. Felipe , E. Khomenko

Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause following the intensity distribution of galactic cosmic ray protons above 200 MeV energy. Before this component reached…

Solar and Stellar Astrophysics · Physics 2015-09-09 J. J. Quenby , W. R. Webber