Thermal characteristics and the differential emission measure distribution during a B8.3 flare on July 04, 2009

Abstract

We investigate the evolution of differential emission measure distribution (DEM[T]) in various phases of a B8.3 flare, which occurred on July 04, 2009. We analyze the soft X-ray (SXR) emission in 1.6-8.0 keV range, recorded collectively by Solar Photometer in X-rays (SphinX; Polish) and Solar X-ray Spectrometer (SOXS; Indian) instruments. We make a comparative investigation of the best-fit DEM[T] distributions derived by employing various inversion schemes viz. single gaussian, power-law, functions and Withbroe-Sylwester (W-S) maximum likelihood algorithm. In addition, SXR spectrum in three different energy bands viz. 1.6-5.0 keV (low), 5.0-8.0 keV (high) and 1.6-8.0 keV (combined) is analyzed to determine the dependence of the best-fit DEM[T] distribution on the selection of energy interval. The evolution of DEM[T] distribution, derived using W-S algorithm, reveals the plasma of multi-thermal nature during the rise to the maximum phase of the flare, while of isothermal nature in the post-maximum phase of the flare. Thermal energy content is estimated considering the flare plasma to be of 1) iso-thermal and 2) multi-thermal nature. We find that the energy content during the flare, estimated from the multi-thermal approach, is in good agreement with that derived using the iso-thermal assumption except during the maximum of the flare. Further, (multi-) thermal energy estimated employing low-energy band of the SXR spectrum result in higher values than that derived from the combined-energy band. On the contrary, the analysis of high-energy band of SXR spectrum lead to lower thermal energy than that estimated from the combined-energy band.

arXiv commentAccepted for publication in the ApJ, 12 Figures, 14 Pages

References in corpus (15)

• An Observational Overview of Solar Flares
• CHIANTI - An atomic database for Emission Lines. Version 8
• Evidence of Non-Thermal Particles in Coronal Loops Heated Impulsively by Nanoflares
• RHESSI Line and Continuum Observations of Super-hot Flare Plasma
• Global Energetics of Solar Flares: I. Magnetic Energies
• Global Energetics of Solar Flares: II. Thermal Energies
• Can the Differential Emission Measure constrain the timescale of energy deposition
• Benchmark Test of Differential Emission Measure Codes and Multi-Thermal Energies in Solar Active Regions
• Can we explain non-typical solar flares?
• Solar Flare Composition and Thermodynamics from RESIK X-ray Spectra
• Diagnostics of non-thermal distributions in solar flare spectra observed by RESIK and RHESSI
• Sphinx measurements of the 2009 solar minimum x-ray emission
• Multi-wavelength Diagnostics of the Precursor and Main phases of an M1.8 Flare on 2011 April 22
• Energy-Dependent Timing of Thermal Emission in Solar Flares
• Probing the Role of Magnetic-Field Variations in NOAA AR 8038 in Producing Solar Flare and CME on 12 May 1997

Cited by in corpus (3)

• Soft X-ray Spectral Diagnostics of Multi-thermal Plasma in Solar Flares with Chandrayaan-2 XSM
• Chromospheric response during the precursor and the main phase of a B6.4 flare on August 20, 2005
• Study of temporal and spectral characteristics of the X-ray emission from solar flares