English
Related papers

Related papers: Are Coronal Loops Isothermal or Multithermal? Yes!

200 papers

Rapidly decaying long-period oscillations often occur in hot coronal loops of active regions associated with small (or micro-) flares. This kind of wave activity was first discovered with the SOHO/SUMER spectrometer from Doppler velocity…

Solar and Stellar Astrophysics · Physics 2021-10-01 Tongjiang Wang , Leon Ofman , Ding Yuan , Fabio Reale , Dmitrii Y. Kolotkov , Abhishek K. Srivastava

A complete understanding of Doppler shift in active region loops can help probe the basic physical mechanism involved into the heating of those loops. Here we present observations of upflows in coronal loops detected in a range of…

Solar and Stellar Astrophysics · Physics 2015-06-05 Durgesh Tripathi , Helen Mason , Giulio Del Zanna , Steven Bradshaw

Using the observations recorded by Atmospheric Imaging Assembly (AIA) on-board the Solar Dynamics Observatory (SDO), the Interface Region Imaging Spectrograph (IRIS) and the Extreme-ultraviolet Imaging Spectrometer (EIS) and X-Ray Telescope…

Solar and Stellar Astrophysics · Physics 2018-05-07 G. R. Gupta , Aveek Sarkar , Durgesh Tripathi

The aim of this paper is to validate a methodology for connecting the emission measure of individual solar coronal loops to the integrated emission measure of the entire solar corona, and using this connection to deduce the energetic…

Astrophysics · Physics 2009-11-07 G. Peres , S. Orlando , F. Reale , R. Rosner

EUV observations of warm coronal loops suggest that they are bundles of unresolved strands that are heated impulsively to high temperatures by nanoflares. The plasma would then have the observed properties (e.g., excess density compared to…

Solar and Stellar Astrophysics · Physics 2011-02-11 S. Patsourakos , J. A. Klimchuk

Context: One of the most prominent processes suggested to heat the corona to well above 10^6 K builds on nanoflares, short bursts of energy dissipation. Aims: We compare observations to model predictions to test the validity of the…

Solar and Stellar Astrophysics · Physics 2015-11-04 Leping Li , Hardi Peter , Feng Chen , Jun Zhang

Standing long-period (with the periods longer than several minutes) oscillations in large hot (with the temperature higher than 3 MK) coronal loops have been observed as the quasi-periodic modulation of the EUV and microwave intensity…

Solar and Stellar Astrophysics · Physics 2016-06-15 Sanjay Kumar , V. M. Nakariakov , Y. -J. Moon

We study the propagation properties of slow magneto-acoustic waves in a multi-thermal coronal loop using a 3D MHD model, for the first time. A bundle of 33 vertical cylinders, each of 100{\,}km radius, randomly distributed over a circular…

Solar and Stellar Astrophysics · Physics 2024-06-06 S. Krishna Prasad , T. Van Doorsselaere

Context. Transverse oscillations of coronal structures are currently intensively studied to explore the associated magnetohydrodynamic wave physics and perform seismology of the local medium. Aims. We make a first attempt to measure the…

Solar and Stellar Astrophysics · Physics 2020-07-01 C. R. Goddard , G. Nisticò

The Coronal Multichannel Polarimeter (CoMP) measures not only the polarization of coronal emission, but also the full radiance profiles of coronal emission lines. For the first time, CoMP observations provide high-cadence image sequences of…

Solar and Stellar Astrophysics · Physics 2016-10-05 H. Tian , S. Tomczyk , S. W. McIntosh , C. Bethge , G. de Toma , S. Gibson

We apply a new method to determine the magnetic field in coronal loops using observations of coronal loop oscillations. We analyze seven Doppler shift oscillation events detected by SUMER in the hot flare line Fe XIX to obtain oscillation…

Astrophysics · Physics 2008-11-26 Tongjiang Wang , Davina E. Innes , Jiong Qiu

Aims: On 13 June 1998, the TRACE satellite was fortuitously well placed to observe the effects of a flare-induced EIT wave in the corona, and its subsequent interaction with coronal magnetic loops. In this study, we use these TRACE…

Solar and Stellar Astrophysics · Physics 2015-05-30 I. Ballai , D. B. Jess , M. Douglas

Spicules have been proposed as significant contributors to the mass and energy balance of the corona. While previous observations have provided a glimpse of short-lived transient brightenings in the corona that are associated with spicules,…

Solar and Stellar Astrophysics · Physics 2017-10-19 Bart De Pontieu , Ineke De Moortel , Juan Martinez-Sykora , Scott McIntosh

Condensations in the more than 10^6 K hot corona of the Sun are commonly observed in the extreme ultraviolet (EUV). While their contribution to the total solar EUV radiation is still a matter of debate, these condensations certainly provide…

Solar and Stellar Astrophysics · Physics 2012-09-06 H. Peter , S. Bingert , S. Kamio

Intensity oscillations of coronal bright points (BPs) have been studied for past several years. It has been known for a while that these BPs are closed magnetic loop like structures. However, initiation of such intensity oscillations is…

Solar and Stellar Astrophysics · Physics 2015-09-23 K. Chandrashekhar , Aveek Sarkar

Coronal loops, seen in solar coronal images, are believed to represent emission from magnetic flux tubes with compact cross-sections. We examine the 3D structure of plasma above an active region in a radiative magnetohydrodynamic simulation…

Solar and Stellar Astrophysics · Physics 2022-03-09 A. Malanushenko , M. C. M. Cheung , C. E. DeForest , J. A. Klimchuk , M. Rempel

We use a combination of analytical theory, numerical simulation, and data analysis to study the propagation of acoustic waves along coronal loops. We show that the intensity perturbation of a wave depends on a number of factors, including…

Astrophysics · Physics 2009-11-10 J. A. Klimchuk , S. E. M. Tanner , I. De Moortel

Coronal loops interconnecting two active regions, called as interconnecting loops (ILs), are prominent large-scale structures in the solar atmosphere. They carry a significant amount of magnetic flux, therefore are considered to be an…

Solar and Stellar Astrophysics · Physics 2018-06-27 Guohui Du , Yao Chen , Chunming Zhu , Chang Liu , Lili Ge , Bing Wang , Chuanyang Li , Haimin Wang

How magnetic energy is injected and released in the solar corona, keeping it heated to several million degrees, remains elusive. Coronal heating generally increases with increasing magnetic field strength. From comparison of a non-linear…

Solar and Stellar Astrophysics · Physics 2017-07-19 Sanjiv K. Tiwari , Julia K. Thalmann , Navdeep K. Panesar , Ronald L. Moore , Amy R. Winebarger

The heating of the solar chromosphere and corona to the observed high temperatures, imply the presence of ongoing heating that balances the strong radiative and thermal conduction losses expected in the solar atmosphere. It has been…