English
Related papers

Related papers: Enthalpy-based Thermal Evolution of Loops: II. Imp…

200 papers

Observational and theoretical evidence suggests that coronal heating is impulsive and occurs on very small cross-field spatial scales. A single coronal loop could contain a hundred or more individual strands that are heated…

Astrophysics · Physics 2009-11-13 J. A. Klimchuk , S. Patsourakos , P. J. Cargill

Plasma-filled loop structures are common in the solar corona. Because detailed modeling of the dynamical evolution of these structures is computationally costly, an efficient method for computing approximate but quick physics-based…

Solar and Stellar Astrophysics · Physics 2022-01-12 Abhishek Rajhans , Durgesh Tripathi , Stephen Bradshaw , Vinay Kashyap , James Klimchuk

Using the "enthalpy-based thermal evolution of loops" (EBTEL) model, we investigate the hydrodynamics of the plasma in a flaring coronal loop in which heat conduction is limited by turbulent scattering of the electrons that transport the…

Solar and Stellar Astrophysics · Physics 2018-01-31 Nicolas Bian , A. Gordon Emslie , Duncan Horne , Eduard P. Kontar

The Enthalpy Based Thermal Evolution of Loops (EBTEL) approximate model for static and dynamic coronal loops is developed to include the effect of a loop cross-sectional area which increases from the base of the transition region (TR) to…

Solar and Stellar Astrophysics · Physics 2021-11-19 P. J. Cargill , S. J. Bradshaw , J. A. Klimchuk , W. T. Barnes

The structure of the solar corona is made of magnetic flux tubes or loops. Due to the lack of contrast with their environment, observing and studying coronal loops in the quiet Sun is extremely difficult. In this work we use a differential…

Solar and Stellar Astrophysics · Physics 2022-08-17 C. Mac Cormack , M. López Fuentes , C. H. Mandrini , D. G. Lloveras , A. M. Vásquez

The excess temperature of the solar corona over the photosphere poses a challenge. Multiple energetic events contribute to maintaining the corona at such high temperatures. The energy released in different events can vary across several…

Solar and Stellar Astrophysics · Physics 2023-02-21 Abhishek Rajhans

The evolution of a coronal loop is studied by means of numerical simulations of the fully compressible three-dimensional magnetohydrodynamic equations using the HYPERION code. The footpoints of the loop magnetic field are advected by random…

Solar and Stellar Astrophysics · Physics 2016-01-22 R. B. Dahlburg , G. Einaudi , B. D. Taylor , I. Ugarte-Urra , H. P. Warren , A. F. Rappazzo , M. Velli

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

We study a 2D cellular automaton (CA) model for the evolution of coronal loop plasmas. The model is based on the idea that coronal loops are made of elementary magnetic strands that are tangled and stressed by the displacement of their…

Solar and Stellar Astrophysics · Physics 2017-03-22 Marcelo López Fuentes , James A. Klimchuk

The brightness of the emission from coronal loops in the solar atmosphere is strongly dependent on the temperature and density of the confined plasma. After a release of energy, these loops undergo a heating and upflow phase, followed by a…

Solar and Stellar Astrophysics · Physics 2019-03-20 C. D. Johnston , S. J. Bradshaw

We investigate the relative contributions from the transition region and corona of coronal loops observed by the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO). Using EBTEL (Enthalpy-Based Thermal Evolution of…

Solar and Stellar Astrophysics · Physics 2021-01-06 Samuel J. Schonfeld , James A. Klimchuk

We analyze and model an M1.0 flare observed by SDO/AIA and Hinode/EIS to investigate how flare loops are heated and evolve subsequently. The flare is composed of two distinctive loop systems observed in EUV images. The UV 1600 \AA emission…

Solar and Stellar Astrophysics · Physics 2015-06-11 Y. Li , J. Qiu , M. D. Ding

The properties expected of "hot" non-flaring plasmas due to nanoflare heating in active regions are investigated using hydrodynamic modeling tools, including a two-fluid development of the EBTEL code. Here we study a single nanoflare and…

Solar and Stellar Astrophysics · Physics 2016-09-28 W. T. Barnes , P. J. Cargill , S. J. Bradshaw

Due to their characteristic temperature and density, loop structures in active regions (ARs) can be seen bright in extreme ultraviolet (EUV) and soft X-ray images. The semiempirical determination of the three-dimensional (3D) distribution…

Solar and Stellar Astrophysics · Physics 2020-12-16 F. A. Nuevo , C. Mac Cormack , M. López Fuentes , A. M. Vásquez , C. H. Mandrini

Recent observations in extreme-ultraviolet (EUV) wavelengths reveal an EUV late phase in some solar flares that is characterized by a second peak in warm coronal emissions ($\sim3$~MK) several tens of minutes to a few hours after the soft…

Solar and Stellar Astrophysics · Physics 2018-05-02 Yu Dai , Mingde Ding

We model the hydrodynamic evolution of the plasma confined in a coronal loop, 30000 km long, subject to the heating of nanoflares due to intermittent magnetic dissipative events in the MHD turbulence produced by loop footpoint motions. We…

Astrophysics · Physics 2009-11-13 F. Reale , G. Nigro , F. Malara , G. Peres , P. Veltri

To simulate the energy balance of coronal plasmas on macroscopic scales, we often require the specification of the coronal heating mechanism in some functional form. To go beyond empirical formulations and to build a more physically…

Solar and Stellar Astrophysics · Physics 2016-12-14 Cooper Downs , Roberto Lionello , Zoran Mikić , Jon A. Linker , Marco Velli

The nanoflare model of coronal heating is one of the most successful scenarios to explain, within a single framework, the diverse set of coronal observations available with the present instrument resolutions. The model is based on the idea…

Solar and Stellar Astrophysics · Physics 2022-10-06 Marcelo López Fuentes , James A. Klimchuk

The expansion of coronal loops in the transition region may considerably influence the diagnostics of the plasma emission measure. The cross sectional area of the loops is expected to depend on the temperature and pressure, and might be…

Solar and Stellar Astrophysics · Physics 2015-06-18 M. Guarrasi , F. Reale , S. Orlando , A. Mignone , J. A. Klimchuk

Numerous recent X-ray observations of coronal loops in both active regions (ARs) and solar flares have shown clearly that elemental abundances vary with time. Over the course of a flare, they have been found to move from coronal values…

Solar and Stellar Astrophysics · Physics 2024-07-25 Jeffrey W. Reep , John Unverferth , Will T. Barnes , Sherry Chhabra
‹ Prev 1 2 3 10 Next ›