English
Related papers

Related papers: Propagating Intensity Disturbances in Fan-like Cor…

200 papers

On 2011 May 30, quasi-periodic fast propagating (QFP) magnetosonic waves accompanied by a C2.8 flare were directly imaged by the Atomospheric Imaging Assembly instrument on board the Solar Dynamics Observatory. The QFP waves successively…

Solar and Stellar Astrophysics · Physics 2015-06-04 Yuandeng Shen , Yu Liu

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

To study the dynamics of coronal holes and the role of waves in the acceleration of the solar wind, spectral observations were performed over polar coronal hole regions with the SUMER spectrometer on SoHO and the EIS spectrometer on Hinode.…

Solar and Stellar Astrophysics · Physics 2009-05-08 D. Banerjee , L. Teriaca , G. R. Gupta , S. Imada , G. Stenborg , S. K. Solanki

Plasma upflows with a Doppler shift exceeding -10 km/s at active region (AR) boundaries are considered potential sources of the nascent slow solar wind. We investigate the driving mechanisms of a pair of coronal upflow regions on the…

Since their discovery by SDO/AIA in EUV, rapid (phase speeds of 1000 km/s), quasi-periodic, fast-mode propagating wave trains (QFPs) have been observed accompanying many solar flares. They typically propagate in funnel-like structures…

Solar and Stellar Astrophysics · Physics 2018-06-27 Leon Ofman , Wei Liu

In coronal loop modeling, it is commonly assumed that the loops are semi-circular with a uniform cross-sectional area. However, observed loops are rarely semi-circular, and extrapolations of the magnetic field show that the field strength…

Solar and Stellar Astrophysics · Physics 2022-07-20 Jeffrey W. Reep , Ignacio Ugarte-Urra , Harry P. Warren , Will T. Barnes

A comparison between a Coronal Hole (CH) and the adjacent Quiet-Sun (QS) has been performed using spectroscopic diagnostics of Hinode/ the EUV Imaging Spectrometer (EIS). Coronal funnels play an important role in the formation and…

Solar and Stellar Astrophysics · Physics 2015-11-04 P. Kayshap , D. Banerjee , A. K. Srivastava

Active region fan loops in AR 11076 were studied, in search of oscillations, using high cadence spectroscopic observations from EIS on board Hinode combined with imaging sequences from the AIA on board SDO. Spectra from EIS were analyzed in…

Solar and Stellar Astrophysics · Physics 2012-08-08 S. Krishna Prasad , D. Banerjee , Jagdev Singh

One of the major discoveries of Hinode's Extreme-ultraviolet Imaging Spectrometer (EIS) is the presence of upflows at the edges of active regions. As active regions are magnetically connected to the large-scale field of the corona, these…

Observations suggest that in normal period radio pulsars, coherent curvature radiation is excited within 10$\%$ of the light cylinder. The coherence is attributed to Langmuir mode instability in a relativistically streaming one-dimensional…

High Energy Astrophysical Phenomena · Physics 2022-08-15 Sk. Minhajur Rahaman , Dipanjan Mitra , George I. Melikidze

The signatures of energy release and energy transport for a kink-unstable coronal flux rope are investigated via forward modelling. Synthetic intensity and Doppler maps are generated from a 3D numerical simulation. The CHIANTI database is…

Solar and Stellar Astrophysics · Physics 2017-06-21 Ben Snow , Gert J. J. Botha , Stephane Regnier , Richard J. Morton , Erwin Verwichte , Peter R Young

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

The profiles of emission lines formed in the corona contain information on the dynamics and the heating of the hot plasma. Only recently has data with sufficiently high spectral resolution become available for investigating the details of…

Solar and Stellar Astrophysics · Physics 2015-05-18 H. Peter

Coronal loops reveal crucial information about the nature of both coronal magnetic fields and coronal heating. The shape of the corresponding flux tube cross section and how it varies with position are especially important properties. They…

Solar and Stellar Astrophysics · Physics 2020-07-31 James A. Klimchuk , Craig E. DeForest

Metrewave solar type-III radio bursts offer a unique means to study the properties of turbulence across the coronal heights.Theoretical models have shown that the apparent intensity and size of the burst sources evolve at sub-second scales…

Solar and Stellar Astrophysics · Physics 2021-11-24 Atul Mohan

Plasma blobs are observed to be weak density enhancements as radially stretched structures emerging from the cusps of quiescent coronal streamers. In this paper, it is suggested that the formation of blobs is a consequence of an intrinsic…

Solar and Stellar Astrophysics · Physics 2011-02-11 Y. Chen , X. Li , H. Q. Song , Q. Q. Shi , S. W. Feng , L. D. Xia

This work addresses the problem of plasma condensation and ``catastrophic cooling'' in solar coronal loops. We have carried out numerical calculations of coronal loops and find several classes of time-dependent solutions (static, periodic,…

Astrophysics · Physics 2009-11-10 D. A. N. Mueller , H. Peter , V. H. Hansteen

Recent spectroscopic observations have revealed the ubiquitous presence of blueward asymmetries of emission lines formed in the solar corona and transition region. These asymmetries are most prominent in loop footpoint regions, where a…

Solar and Stellar Astrophysics · Physics 2011-08-11 Hui Tian , Scott W. McIntosh , Bart De Pontieu , Juan Martinez-Sykora , Marybeth Sechler , Xin Wang

Using joint observations from Hinode/EIS and the Atmospheric Imaging Array (AIA) on the Solar Dynamics Observatory we explore the asymmetry of coronal EUV line profiles. We find that asymmetries exist in all of the spectral lines studied,…

Solar and Stellar Astrophysics · Physics 2012-01-26 Marybeth Sechler , Scott W. McIntosh , Hui Tian , Bart De Pontieu

Observations reveal a correspondence between chromospheric type II spicules and bright upwardly moving fronts in the corona observed in the EUV band. However, theoretical considerations suggest that these flows are unlikely to be the main…

Solar and Stellar Astrophysics · Physics 2014-09-05 A. Petralia , F. Reale , S. Orlando , J. A. Klimchuk