Basic information
NuSTAR observation time (orbit 4): 2020-09-12 14:00:00 - 14:23:00
Instrument | Wavelength regime | Cadence | Resolution/px |
---|---|---|---|
NuSTAR | SXR | 20s | low |
XRT Be-Thin | SXR | 200s | 1” |
AIA | EUV | 12 s | 0.6” |
STEREO-A EUVI | EUV | 5 min | 1.6” |
Flare Location

Flare location determined by finding the position of the center of mass of the 90% contour of the XRT submap around the flare area. To align with AIA, this requires ~25” offset in x and ~25” in y from the location in XRT header (coordinates below given in XRT frame).
<SkyCoord (Helioprojective: obstime=2020-09-12 14:10:41, rsun=695508000.0 m, observer=<HeliographicStonyhurst Coordinate (obstime=2020-09-12 14:10:41): (lon, lat, radius) in (deg, deg, m)
( 0., 7.23219551, 1.50542567e+11)>): (Tx, Ty) in arcsec
(-764.11429488, 1.2117822)>
Flare time evolution (AIA and STEREO)
3-minute integrated AIA 193 images
Source | Image | Base Difference | Sobel Filter |
---|---|---|---|
AIA 193 | ![]() |
![]() |
![]() |
Lightcurves
AIA and XRT at native cadence, calculated using 40” box.
STEREO-A at native cadence (5 minutes), calculated using 40” box.
NuSTAR images at 20s cadence (made by Sam), adjusted to counts, calculated using 160” square box.
Masks
Find regions of brightening/dimming by comparing the change in the flare region vs the quiet Sun region. A pixel is included in ‘brightening’ mask if the value of that pixel in the difference image (integrate flare X-ray peak minus integrated pre-flare) is >3x greater than standard deviation of the average flux difference in Quiet Sun ((𝜎_QSdiff) in those same time ranges (details in code below). Likewise with ‘dimming’ mask, only the pixel value is less than -3x 𝜎_QSdiff. The total mask is sum of both masks in each channel.