XRT vs. AIA Synoptics

Yingna Su2011-Jan-25

• We take a look at the recent XRT 9-filter synoptic observations on Jan 5 (12 UT), Jan 9 (20 UT), and Jan 13 (20 UT). We then compare them with the corresponding AIA images.

• We illustrate our results using the data taken on Jan 5. Two movies with XRT and AIA observations at different filters and channels can be found at: http://hea-www.harvard.edu/trace/SSXG/ynsu/XRT-AIA/XRT-AIA.html

XRT observations

• Thin-Be and Al/poly+Ti/poly are two ideal filters for very dynamic active region observations.

• All three poly filter images look similar. If we need thinner filters for normal active regions, then C-poly and Ti-poly are good options, since spots are more visible in Al-poly images.

• Al-med and Be-med are two good options for the thicker-filter AR observations. Very few features can be identified in Thick-Al images.

XRT vs. AIA• 335 channel in AIA is the one that looks

closest to XRT images.• In all XRT filters, Al-mesh is the one looks

closest to 335 Å image. See Figure 1 in next slide. The AIA 335 Å image in this presentation is summed over 3 minutes.

Figure 1

AIA 335 XRT Al-mesh

• For some active regions, most XRT filters can see structures which are not visible in all AIA filters.

Figure 2

XRT Thin-Be AIA 335

• Large scale loop structures surrounding the active regions and loop structures at the limb are seen in AIA, but are not visible in XRT. AIA can see dark filaments, which are not observed by XRT.

Figure 3

AIA 171 XRT Al/poly+Ti/poly