Observations of a Radio-quiet Solar Preflare
arXiv:1709.06417 · doi:10.1007/s11207-017-1175-3
Abstract
The preflare phase of the flare SOL2011-08-09T03:52 is unique in its long duration, its coverage by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Nobeyama Radioheliograph, and the presence of three well-developed soft X-ray (SXR) peaks. No hard X-rays (HXR) are observed in the preflare phase. Here we report that also no associated radio emission at 17 GHz was found despite the higher sensitivity of the radio instrument. The ratio between the SXR peaks and the upper limit of the radio peaks is larger by more than one order of magnitude compared to regular flares. The result suggests that the ratio between acceleration and heating in the preflare phase was different than in regular flares. Acceleration to relativistic energies, if any, occurred with lower efficiency.
arXiv comment9 pages, 3 figures, accepted by Solar Physics
References in corpus (13)
- Collisional Plasma Models with APEC/APED: Emission Line Diagnostics of Hydrogen-like and Helium-like Ions
- Global Energetics of Thirty-Eight Large Solar Eruptive Events
- Recent Advances in Understanding Particle Acceleration Processes in Solar Flares
- The spectral evolution of impulsive solar X-ray flares
- Global Energetics of Solar Flares: V. Energy Closure in Flares and Coronal Mass Ejections
- Observations of conduction driven evaporation in the early rise phase of solar flares
- Size dependence of solar X-ray flare properties
- Energy Release and Particle Acceleration in Flares: Summary and Future Prospects
- Are Heating Events in the Quiet Solar Corona Small Flares? - Multiwavelength Observations of Individual Events
- Spectral Hardening of Large Solar Flares
- Thermal to Nonthermal Energy Partition at the Early Rise Phase of Solar Flares
- Plasma heating in the very early phase of solar flares
- Where is the chromospheric response to conductive energy input from a hot pre-flare coronal loop?
Cited by in corpus (5)
- Critical Science Plan for the Daniel K. Inouye Solar Telescope (DKIST)
- Quasi-periodic pulsation detected in Lyman-alpha emission during solar flares
- Observations of Electron-driven Evaporation during a Flare Precursor
- Chromospheric response during the precursor and the main phase of a B6.4 flare on August 20, 2005
- Combined Radio and Space-based Solar Observations: From Techniques to New Results