English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The spatial and spectral properties of three solar flare coronal X-ray loopsare studied before, during and after the peak X-ray emission. Usingobservations from the Ramaty High Energy Solar Spectroscopic Imager (RHESSI),we deduce the temporal changes in emitting X-ray length, corpulence, volume,position, number density and thermal pressure. We observe a decrease in theloop length, width and volume before the X-ray peak, and an increasing numberdensity and thermal pressure. After the X-ray peak, volume increases and loopcorpulence grows due to an increasing width. The volume variations are morepronounced than the position variations, often known as magnetic linecontraction. We believe this is the first dedicated study of the temporalevolution of X-ray loop lengths and widths. Collectively, the observations alsoshow for the first time three temporal phases given by peaks in temperature,X-ray emission and thermal pressure, with minimum volume coinciding with theX-ray peak. Although the volume of the flaring plasma decreases before the peakin X-ray emission, the relationship between temperature and volume does notsupport simple compressive heating in a collapsing magnetic trap model. Withina low beta plasma, shrinking loop widths perpendicular to the guiding field canbe explained by squeezing the magnetic field threading the region. Plasmaheating leads to chromospheric evaporation and growing number density,producing increasing thermal pressure and decreasing loop lengths as electronsinteract at shorter distances and we believe after the X-ray peak, theincreasing loop corpulence.

Temporal variations of X-ray solar flare loops: length, corpulence, position, temperature, plasma pressure and spectra