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Related papers: Macro-microturbulence in the solar photosphere

200 papers

In order to investigate the origin of the interstellar turbulence, detailed observations in the CO J=1--0 and 3--2 lines have been carried out in an interacting region of a molecular cloud with an HII region. As a result, several 1,000 to…

We perform numerical simulations of solid particle motion in a shearing box model of a protoplanetary disc. The accretion flow is turbulent due to the action of the magnetorotational instability. Aerodynamic drag on the particles is…

Astrophysics · Physics 2009-11-13 Augusto Carballido , James M. Stone , Neal J. Turner

The Sun's internal rotation {\Omega}(r,{\Theta}) has previously been measured using helioseismology techniques and found to be a complex function of co-latitude, {\theta}, and radius, r. From helioseismology and observations of apparently…

Solar and Stellar Astrophysics · Physics 2017-02-08 Ian Cunnyngham , Marcelo Emilio , Jeff Kuhn , Isabelle Scholl , Rock Bush

A new set of accurately measured frequencies of solar oscillations are used to infer the rotation rate inside the Sun, as a function of radial distance as well as latitude. We have adopted a regularized least squares technique with…

Astrophysics · Physics 2009-10-30 H. M. Antia , Sarbani Basu , S. M. Chitre

Fluctuations in the Sun's photospheric magnetic field are the primary source of the turbulence that can heat and accelerate the solar atmosphere, and thus play an important role in the production and evolution of the solar wind that…

Solar and Stellar Astrophysics · Physics 2025-11-26 Rohit Chhiber , Raphael Attie , William H. Matthaeus , Sohom Roy , Barbara J. Thompson

The interaction of magnetic fields and convection is investigated in the context of the coronal heating problem. We study the motions of photospheric magnetic elements using filtergrams obtained at the Swedish Vacuum Solar Telescope at La…

Velocity anisotropy induced by MHD turbulence is investigated using computational simulations and molecular line observations of the Taurus molecular cloud. A new analysis method is presented to evaluate the degree and angle of velocity…

Astrophysics · Physics 2009-11-13 Mark Heyer , Hao Gong , Eve Ostriker , Christopher Brunt

We made high-resolution spectroscopic observations of limb-spicules in H-alpha using the Vertical Spectrograph of Domeless Solar Telescope at Hida Observatory. While more than half of the observed spicules have Gaussian line-profiles, some…

Solar and Stellar Astrophysics · Physics 2015-05-18 Makiko Shoji , Takara Nishikawa , Reizaburo Kitai , Satoru Ueno

We present the first observational study of the onset and evolution of solar flare turbulence in the lower solar atmosphere on an unprecedented time scale of 1.7 s using the Interface Region Imaging Spectrograph observing plasma at a…

Solar and Stellar Astrophysics · Physics 2018-12-27 N. L. S. Jeffrey , L. Fletcher , N. Labrosse , P. J. A. Simões

We present the first measurement of the scale-dependent power anisotropy of Elsasser variables in imbalanced fast solar wind turbulence. The dominant Elsasser mode is isotropic at lower spacecraft frequencies but becomes increasingly…

Plasma Physics · Physics 2015-05-19 R. T. Wicks , T. S. Horbury , C. H. K. Chen , A. A. Schekochihin

The Rossiter-McLaughlin effect observed for transiting exoplanets often requires prior knowledge of the stellar projected equatorial rotational velocity. This is usually provided by measuring the broadening of spectral lines, however this…

Solar and Stellar Astrophysics · Physics 2015-06-22 Amanda P. Doyle , Guy R. Davies , Barry Smalley , William J. Chaplin , Yvonne Elsworth

Radial differential rotation is an important factor in stellar dynamo theory. In the Sun, helioseismology has revealed a near surface shear layer in the upper 5 to 10% of the convection zone. At low to midlatitudes, the rotation velocity…

Solar and Stellar Astrophysics · Physics 2025-10-15 T. Corbard , M. Faurobert , B. Gelly , R. Douet , D. Laforgue

In this paper, I review the results of 3-D evolution of the inner heliosphere over the solar cycle #23, based on observations of interplanetary scintillation (IPS) made at 327 MHz using the Ooty Radio Telescope. The large-scale features of…

Solar and Stellar Astrophysics · Physics 2011-04-04 P. K. Manoharan

Observations from Parker Solar Probe's first five orbits are used to investigate the helioradial evolution of probability density functions (PDFs) of fluctuations of magnetic field components, between \(\sim 28\) - 200 \(\rs\).…

Solar and Stellar Astrophysics · Physics 2022-11-09 Rohit Chhiber

We study the anisotropy with respect to the local magnetic field of turbulent magnetic fluctuations at magnetofluid scales in the solar wind. Previous measurements in the fast solar wind obtained axisymmetric anisotropy, despite that the…

Solar and Stellar Astrophysics · Physics 2019-01-31 Andrea Verdini , Roland Grappin , Olga Alexandrova , Sonny Lion

Open star clusters from the MWSC (Milky Way Star Clusters) catalogue have been used to determine the Galactic rotation parameters. The circular rotation velocity of the solar neighborhood around the Galactic center has been found from data…

Astrophysics of Galaxies · Physics 2016-09-30 V. V. Bobylev , A. T. Bajkova , K. S. Shirokova

We study a granular-sized magnetic flux emergence event that occurred in NOAA 11024 in July 2009. The observations were made with the CRISP spectropolarimeter at the Swedish 1 m Solar Telescope achieving a spatial resolution of 0.14".…

Solar and Stellar Astrophysics · Physics 2015-06-18 Ada Ortiz , Luis Bellot Rubio , Viggo Hansteen , Jaime de la Cruz Rodriguez , Luc Rouppe van der Voort

Magnetic turbulence is anisotropic as the directions of motion are constrained by the magnetic field. Such anisotropy can be observed in velocity centroids obtained from spectroscopic observations. We use magnetohydrodynamics (MHD)…

Astrophysics of Galaxies · Physics 2020-08-13 D. Hernández-Padilla , A. Esquivel , A. Lazarian , D. Pogosyan , D. Kandel , J. Cho

Using high cadence observations from the Hydrogen-alpha Rapid Dynamics camera imaging system on the Dunn Solar Telescope, we present an investigation of the statistical properties of transverse oscillations in spicules captured above the…

Solar and Stellar Astrophysics · Physics 2022-05-18 W. Bate , D. B. Jess , V. M. Nakariakov , S. D. T. Grant , S. Jafarzadeh , M. Stangalini , P. H. Keys , D. J. Christian , F. P. Keenan

We measure the power and spectral index anisotropy of high speed solar wind turbulence from scales larger than the outer scale down to the ion gyroscale, thus covering the entire inertial range. We show that the power and spectral indices…

Space Physics · Physics 2015-05-18 R. T. Wicks , T. S. Horbury , C. H. K. Chen , A. A. Schekochihin