English
Related papers

Related papers: Unresolved fine-scale structure in solar coronal l…

200 papers

We carry out a study of the global three-dimensional (3D) structure of the electron density and temperature of the quiescent inner solar corona ($r<1.25 R_\odot$) by means of tomographic reconstructions and magnetohydrodynamic simulations.…

Solar and Stellar Astrophysics · Physics 2020-06-17 D. G. Lloveras , A. M. Vásquez , F. A. Nuevo , C. Mac Cormack , N. Sachdeva , W. Manchester , B. Van der Holst , R. A. Frazin

Several items on the diagnostics and interpretation of coronal loop observations are under debate. In this work, we analyze a well-defined loop system detected in a time-resolved observation in several spectral bands. The dataset includes…

Astrophysics · Physics 2009-11-11 Fabio Reale , Angela Ciaravella

Tomography of the solar corona can provide cruicial constraints for models of the low corona, unique information on changes in coronal structure and rotation rates, and a valuable boundary condition for models of the heliospheric solar…

Instrumentation and Methods for Astrophysics · Physics 2015-09-11 Huw Morgan

Some high-resolution observations have revealed that the active-region solar corona is filled with myriads of thin strands even in apparently uniform regions with no resolved loops. This fine structure can host collective oscillations…

Solar and Stellar Astrophysics · Physics 2019-08-28 Manuel Luna , Ramon Oliver , Patrick Antolin , Inigo Arregui

Evidence for small amounts of very hot plasma has been found in active regions and might be the indication of an impulsive heating, released at spatial scales smaller than the cross section of a single loop. We investigate the heating and…

Solar and Stellar Astrophysics · Physics 2016-01-13 E. Tajfirouze , F. Reale , A. Petralia , P. Testa

The observed solar activity is believed to be driven by the dissipation of nonpotential magnetic energy injected into the corona by dynamic processes in the photosphere. The enormous range of scales involved in the interaction makes it…

Solar and Stellar Astrophysics · Physics 2015-06-12 Vadim M. Uritsky , Joseph M. Davila , Leon Ofman , Aaron J. Coyner

The motion of faint propagating disturbances (PD) in the solar corona reveals an intricate structure which must be defined by the magnetic field. Applied to quiet Sun observations by the Atmospheric Imaging Assembly (AIA)/Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2022-07-20 Huw Morgan , Marianna Korsos

High resolution spectra from the Hinode EUV Imaging Spectrometer (EIS) have revealed that coronal spectral line profiles are sometimes asymmetric, with a faint enhancement in the blue wing on the order of 100 km/s. These asymmetries could…

Solar and Stellar Astrophysics · Physics 2015-06-11 David H. Brooks , Harry P. Warren

Within the coronae of stars, abundances of those elements with low first ionization potential (FIP) often differ from their photospheric values. The coronae of the Sun and solar-type stars mostly show enhancements of low-FIP elements (the…

Coronal loops trace out bipolar, arch-like magnetic fields above the Sun's surface. Recent measurements that combine rotational tomography, extreme ultraviolet imaging, and potential-field extrapolation have shown the existence of large…

Solar and Stellar Astrophysics · Physics 2016-11-15 Avery J. Schiff , Steven R. Cranmer

Previous solar observations have shown that coronal loops near 1 MK are difficult to reconcile with simple heating models. These loops have lifetimes that are long relative to a radiative cooling time, suggesting quasi-steady heating. The…

The bulk of solar coronal radiative loss consists of soft X-ray emission from quasi-static loops at the cores of Active Regions. In order to develop diagnostics for determining the heating mechanism of these loops from observations by…

Astrophysics · Physics 2014-11-18 P. C. H. Martens

The variation of the vector magnetic field along structures in the solar corona remains unmeasured. Using a unique combination of spectropolarimetry and stereoscopy, we infer and compare the vector magnetic field structure and…

Solar and Stellar Astrophysics · Physics 2016-12-14 Thomas A. Schad , Matthew J. Penn , Haosheng Lin , Philip G. Judge

The condensations composing coronal rain, falling down along loop-like structures observed in cool chromospheric lines such as H$\alpha$ and \ion{Ca}{2} H, have long been a spectacular phenomenon of the solar corona. However, considered a…

Solar and Stellar Astrophysics · Physics 2015-05-28 Patrick Antolin , Erwin Verwichte

We present a new model for the coronal structure of rapidly rotating solar-type stars. The presence of prominences trapped in co-rotation 2 to 5 stellar radii above the stellar surface has been taken as evidence that the coronae of these…

Astrophysics · Physics 2009-11-11 M. Jardine , A. A. van Ballegooijen

How the solar corona is heated to high temperatures remains an unsolved mystery in solar physics. In the present study we analyse observations of 50 whole active-region loops taken with the Extreme-ultraviolet Imaging Spectrometer (EIS) on…

Solar and Stellar Astrophysics · Physics 2017-06-28 Haixia Xie , Maria S. Madjarska , Bo Li , Zhenghua Huang , Lidong Xia , Thomas Wiegelmann , Hui Fu , Chaozhou Mou

The Wide-field Imager for Parker Solar Probe (WISPR) captures unprecedented white-light images of the solar corona and inner heliosphere. Thanks to the uniqueness of Parker Solar Probe's (PSP) orbit, WISPR is able to image ``locally''…

Stars like our Sun form in self-gravitating dense and cold structures within interstellar clouds, called pre-stellar cores. Although much is known about the physical structure of dense clouds just before and soon after the switch-on of a…

Coronal loops are fundamental building blocks of the solar active regions and the corona. Therefore, a clear understanding of the physics of coronal loops will help us understand the physics of active region heating in particular and…

Solar and Stellar Astrophysics · Physics 2011-02-11 D. Tripathi , H. E. Mason , B. N. Dwivedi , G. Del Zanna , P. R. Young

Above the top of the solar corona, the young slow solar wind transitions from low-beta, magnetically structured flow dominated by radial structures, to high-beta, less structured flow dominated by hydrodynamics. This transition, long…

Solar and Stellar Astrophysics · Physics 2016-09-21 C. E. DeForest , W. H. Matthaeus , N. M. Viall , S. R. Cranmer
‹ Prev 1 4 5 6 7 8 10 Next ›