Non-thermal Electron Energization During the Impulsive Phase of an X9.3 Flare Revealed by Insight-HXMT
- 1 September 2021
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 918 (2), 42
- https://doi.org/10.3847/1538-4357/ac0cfb
Abstract
The X9.3 flare SOL20170906T11:55 was observed by the CsI detector aboard the first Chinese X-ray observatory Hard X-ray Modulation telescope (Insight-HXMT). Using the wavelets method, we report 22 s quasiperiodic pulsations during the impulsive phase. The spectra from 100 keV to 800 keV show the evolution with the gamma-ray flux of a power-law photon index from similar to 1.8 before the peak, similar to 2.0 around the flare peak, to similar to 1.8 again. The gyrosynchrotron microwave spectral analysis reveals a 36.'' 6 +/- 0.'' 6 radius gyrosynchrotron source with mean transverse magnetic field around 608.2 Gauss. The penetrated >= 10 keV non-thermal electron density is about 10(6.7) cm(-3) at peak time. The magnetic field strength followed the evolution of high-frequency radio flux. Further gyrosynchrotron source modeling analysis implies that there exists a quite steady gyrosynchrotron source, and the non-thermal electron density and transverse magnetic field evolution are similar to higher-frequency light curves. The temporal spectral analysis reveals that those non-thermal electrons are accelerated by repeated magnetic reconnection, likely from a lower corona source.Funding Information
- National Natural Science Foundation of China (U1838103)
- National Natural Science Foundation of China (11622326)
- National Natural Science Foundation of China (U1838201)
- National Natural Science Foundation of China (U1838202)
- National Natural Science Foundation of China (U1631242)
- National Natural Science Foundation of China (11820101002)
- National Program on Key Research and Development Project (2016YFA0400803)
- National Program on Key Research and Development Project (2016YFA0400800)
This publication has 36 references indexed in Scilit:
- Astropy: A community Python package for astronomyAstronomy & Astrophysics, 2013
- Solar flares at submillimeter wavelengthsThe Astronomy and Astrophysics Review, 2013
- The Relationship Between Solar Radio and Hard X-ray EmissionSpace Science Reviews, 2011
- FAST GYROSYNCHROTRON CODESThe Astrophysical Journal, 2010
- Stationary and impulsive injection of electron beams in converging magnetic fieldAstronomy & Astrophysics, 2009
- Quasi-Periodic Pulsations in Solar FlaresSpace Science Reviews, 2009
- Konus-W gamma-ray burst experiment for the GGS Wind spacecraftSpace Science Reviews, 1995
- Temperature and emission measure from goes soft X-ray measurementsSolar Physics, 1994
- Radio Emission from the Sun and StarsAnnual Review of Astronomy and Astrophysics, 1985
- Simplified expressions for the gyrosynchrotron radiation from mildly relativistic, nonthermal and thermal electronsThe Astrophysical Journal, 1982