6533b7d6fe1ef96bd126716d
RESEARCH PRODUCT
Evidence of nonthermal particles in coronal loops heated impulsively by nanoflares
A. M. TitleCharles C. KankelborgFabio RealeJames R. LemenEdward E. DelucaPaola TestaKatharine K. ReevesJean-pierre WuelserSean MckillopSteven H. SaarMats CarlssonJoel C. AllredS. JaeggliB. De PontieuWei LiuNeal E. HurlburtViggo HansteenPaul BoernerLucia KleintAdrian N. DawJuan Martinez-sykoraL. GolubT. D. TarbellHui Tiansubject
High Energy Astrophysical Phenomena (astro-ph.HE)PhysicsMultidisciplinaryFOS: Physical sciencesCoronal holeCoronal loopElectronAstrophysicsCoronaCoronal radiative losses3. Good healthNanoflaresAtmosphereSettore FIS/05 - Astronomia E AstrofisicaAstrophysics - Solar and Stellar Astrophysics13. Climate actionPhysics::Space PhysicsAstrophysics::Solar and Stellar AstrophysicsAstrophysics - High Energy Astrophysical PhenomenaChromosphereSolar and Stellar Astrophysics (astro-ph.SR)description
The physical processes causing energy exchange between the Sun's hot corona and its cool lower atmosphere remain poorly understood. The chromosphere and transition region (TR) form an interface region between the surface and the corona that is highly sensitive to the coronal heating mechanism. High resolution observations with the Interface Region Imaging Spectrograph (IRIS) reveal rapid variability (about 20 to 60 seconds) of intensity and velocity on small spatial scales at the footpoints of hot dynamic coronal loops. The observations are consistent with numerical simulations of heating by beams of non-thermal electrons, which are generated in small impulsive heating events called "coronal nanoflares". The accelerated electrons deposit a sizable fraction of their energy in the chromosphere and TR. Our analysis provides tight constraints on the properties of such electron beams and new diagnostics for their presence in the nonflaring corona.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-10-17 | Science |