Abstract
5 For the first time, we simulate the detailed spectral line emission
from a solar active 6 region (AR) with the Alfvén Wave Solar Model
(AWSoM). We select an AR appearing 7 near disk center on 2018 July 13
and use an NSO/HMI synoptic magnetogram to specify 8 the magnetic field
at the model’s inner boundary. To resolve smaller-scale magnetic 9
features, we apply adaptive mesh refinement to resolve the AR with a
horizontal spatial 10 resolution of 0.35 • (4.5 Mm), four times higher
than the background corona. We then 11 apply the SPECTRUM code informed
with CHIANTI spectral emissivities to calculate 12 spectral lines
forming at temperatures ranging from 0.5 to 3 MK. Comparisons are 13
made between the simulated line intensities and those observed by the
Hinode/EIS 14 instrument where we find close agreement (about 20%
relative error for both loop top 15 and footpoints at a temperature of
about 1.5 MK) across a wide range of loop sizes and 16 temperatures. We
also simulate and compare Doppler velocities and find that simulated 17
flow patterns are of comparable magnitude to what is observed. Our
results demonstrate 18 the broad applicability of the low-frequency
Alfvén wave balanced turbulence theory 19 for explaining the heating of
coronal loops. 20