2017/03/31 by I. N. Sharykin, Ivan N Sharykin, A. G. Kosovichev +7 · 2 citations
Earth and Planetary Sciences · Physics and Astronomy · #Chromosphere #Earthquake Detection and Analysis #Flare #Helioseismology #Ionosphere and magnetosphere dynamics #On board #Photosphere #Radiative transfer #Solar and Space Plasma Dynamics #Solar flare #Solar physics #astro-ph.SR
paper · pdf · doi:10.3847/1538-4357/aa77f1
23 pages, 7 figures
arxiv created 2017/06/08 · openalex publication_date 2017/07/01 · openalex created_date 2017/07/14 · arxiv updated 2017/07/19 · openalex updated_date 2026/08/05
Abstract The X-class solar flare of 2012 October 23 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 the energy release with high temporal and spatial resolutions, using photospheric data from the Helioseismic Magnetic Imager (HMI) on board Solar Dynamics Observatory , and hard X-ray observations made by RHESSI . For this analysis we use level-1 HMI data (filtergrams), obtained by scanning the Fe i line (6731 Å) with the time cadence of ∼3.6 s and spatial resolution of ∼0.″5 per pixel. It is found that the photospheric disturbances caused by the flare spatially coincide with the region of hard X-ray emission but are delayed by ≲4 s. This delay is consistent with predictions of the flare hydrodynamics RADYN models. However, the models fail to explain the magnitude of variations observed by the HMI. The data indicate that the photospheric impact and helioseismic wave might be caused by the electron energy flux, which is substantially higher than that in the current flare radiative hydrodynamic models.