[P-EM14] Frontiers in solar physics

[PEM14-P04] Differential Emission Measure (DEM) Analysis of Small-scale Eruptions in AR 12860

*Cheng-Ying Chiang¹, Ya-Hui Yang¹ (1.Department of Space Science and Engineering, National Central University, Taiwan)

Keywords:Solar flare, Differential Emission Measure

NOAA AR 12860 produced numerous small solar flares and one M-class flare during its solar disk passage. In particular, an impulsive enhancement in GOES soft X-ray emission, which is not defined as a flare and would be called uE hereafter, is found following the gradual M4.7 flare on August 28, 2021. By tracing a sequence of AIA images, we find that the occurrences of both uE and the earlier C7.0 flare were accompanied by jets at the edge area of AR 12860, while the M4.7 flare erupted from the core area of AR 12860. To clarify the potential explosion for the uE, the Differential Emission Measure (DEM) analysis using AIA six filters is employed to obtain the spatial distributions of Emission Measure (EM), EM-weighted temperature, and plasma density, as well as the temporal variations of plasma quantities at the regions of jets and footprints. The derived plasma density map also used to estimate the jet speeds. Besides, the evolution of the hot plasma component (i.e., temperature higher than 1 MK) is extracted from the DEM distribution varying with temperature by a polynomial fitting. Our preliminary results reveal that the plasma heating, cooling, and diffusion are observed for both uE and C7.0 flare, verifying the uE is caused by a small-scale eruption. The plasma properties of these two eruptions will be compared quantitatively in this study.