English
Related papers

Related papers: Can Proton Beam Heating Flare Models Explain Sunqu…

200 papers

Sunquakes are one of the more distinct secondary phenomena related to solar flares, where energy deposition in the lower layers of the Sun's atmosphere excites acoustic waves easily visible in Helioseismic and Magnetic Imager (HMI)…

Solar and Stellar Astrophysics · Physics 2021-02-04 John T. Stefan , Alexander G. Kosovichev

Analysis of the hydrodynamic and helioseismic effects in the photosphere during the solar flare of July 23, 2002, observed by Michelson Doppler Imager (MDI) on SOHO, and high-energy images from RHESSI shows that these effects are closely…

Astrophysics · Physics 2009-11-13 A. G. Kosovichev

The first significant sunquake event of Solar Cycle 25 was observed during the X1.5 flare of May 10, 2022, by the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory. We perform a detailed spectro-polarimetric…

Solar and Stellar Astrophysics · Physics 2023-09-15 Alexander G. Kosovichev , Viacheslav M. Sadykov , John T. Stefan

Several mechanisms have been proposed to explain the transient seis- mic emission, i.e., sunquakes, from some solar flares. Some theories associate high-energy electrons and/or white-light emission with sunquakes. High-energy charged…

Solar and Stellar Astrophysics · Physics 2015-12-09 J. C. Buitrago-Casas , J. C. Martinez Oliveros , C. Lindsey , B. Calvo-Mozo , S. Krucker , L. Glesener , S. Zharkov

While solar flares are primarily associated with enhanced ultraviolet and X-ray emission, a subset of flares exhibit significant continuum brightening in visible light and are classified as white-light flares (WLFs). Despite extensive…

Solar and Stellar Astrophysics · Physics 2026-01-01 Samuel Granovsky , Alexander G. Kosovichev , Irina N. Kitiashvili , Alan A. Wray

One of the leading hypotheses for sunquake generation suggests that flare-accelerated particles originating from the reconnection site in the corona travel down to the chromosphere and photosphere, where they deposit energy through…

Solar and Stellar Astrophysics · Physics 2025-09-09 John Stefan , Alexander Kosovichev

Solar flares involve complex processes that are coupled and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present results from simulations that…

Solar and Stellar Astrophysics · Physics 2015-11-18 Fatima Rubio da Costa , Wei Liu , Vahe' Petrosian , Mats Carlsson

We perform an analysis of the line-of-sight (LOS) observables of the SDO/HMI for models of the solar atmosphere heated by precipitating high-energy electrons during solar flares. The radiative hydrodynamic (RADYN) flare models are obtained…

Solar and Stellar Astrophysics · Physics 2020-04-15 Viacheslav M Sadykov , Alexander G Kosovichev , Irina N Kitiashvili , Graham S Kerr

The solar atmosphere is extremely dynamic, and many important phenomena develop on small scales that are unresolved in observations with the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). For…

Solar and Stellar Astrophysics · Physics 2015-08-06 Irina N. Kitiashvili , Sebastien Couvidat , Andreas Lagg

Sunquakes observed in the form of expanding wave ripples on the surface of the Sun during solar flares represent packets of acoustic waves excited by flare impacts and traveling through the solar interior. The excitation impacts strongly…

Solar and Stellar Astrophysics · Physics 2019-09-04 Alexander G. Kosovichev

The solar active region photospheric magnetic field evolves rapidly during major eruptive events, suggesting appreciable feedback from the corona. Previous studies of these "magnetic imprints" are mostly based on line-of-sight only or…

Solar and Stellar Astrophysics · Physics 2017-04-26 Xudong Sun , J. Todd Hoeksema , Yang Liu , Maria Kazachenko , Ruizhu Chen

The X-class solar flare of October 23, 2012, generated continuum photospheric emission and a strong helioseismic wave ("sunquake") that points to an intensive energy release in the dense part of the solar atmosphere. We study properties of…

Solar and Stellar Astrophysics · Physics 2017-07-19 Ivan N Sharykin , Alexander G Kosovichev , Viacheslav M Sadykov , Ivan V Zimovets , Ivan I Myshyakov

We investigate the cause of the suppressed Balmer series and the origin of the white-light continuum emission in the X1.0 class solar flare on 2014 June 11. We use radiative hydrodynamic simulations to model the response of the flaring…

Solar and Stellar Astrophysics · Physics 2018-08-08 Ondřej Procházka , Aaron Reid , Ryan O. Milligan , Paulo J. A. Simões , Joel C. Allred , Mihalis Mathioudakis

Sunquakes are helioseismic power enhancements initiated by solar flares, but not all flares generate sunquakes. It is curious why some flares cause sunquakes while others do not. Here we propose a hypothesis to explain the disproportionate…

Solar and Stellar Astrophysics · Physics 2021-03-16 Ruizhu Chen , Junwei Zhao

Helioseismic data from the HMI instrument have revealed a sunquake associated with the X1 flare SOL2014-03-29T17:48 in active region NOAA 12017. We try to discover if acoustic-like impulses or actions of the Lorentz force caused the…

Solar and Stellar Astrophysics · Physics 2015-06-22 Philip G. Judge , Lucia Kleint , Alina Donea , Alberto Sainz Dalda , Lyndsay Fletcher

We present radiative hydrodynamic simulations of solar flares generated by the RADYN and RH codes to study the perturbations induced in photospheric Fe I lines by electron beam heating. We investigate how variations in the beam parameters…

Solar and Stellar Astrophysics · Physics 2021-07-07 Aaron J. Monson , Mihalis Mathioudakis , Aaron Reid , Ryan Milligan , David Kuridze

The X2.2-class solar flare of February 15, 2011, produced a powerful sunquake event, representing a helioseismic response to the flare impact in the solar photosphere, which was observed with the HMI instrument on the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2015-05-28 Alexander G. Kosovichev

We present analysis of C7.0 solar flare of Febrary 17, 2013, revealing a strong helioseismic response (sunquake) caused by a very compact impact in the photosphere. This is the weakest known C-class flare generating a sunquake event. To…

Solar and Stellar Astrophysics · Physics 2015-07-15 I. N. Sharykin , A. G. Kosovichev , I. V. Zimovets

Solar Orbiter's four in-situ instruments have recorded numerous energetic electron events at heliocentric distances between 0.5 and 1au. We analyse energetic electron fluxes, spectra, pitch angle distributions, associated Langmuir waves,…

Recent results of a mixed shell model heated asymmetrically by transient increases in nuclear burning indicate the transient generation of small hot spots inside the Sun somewhere between 0.1 and 0.2 solar radii. These hot bubbles are…

Solar and Stellar Astrophysics · Physics 2015-05-18 Attila Grandpierre
‹ Prev 1 2 3 10 Next ›