before, and during the flare. Hα for reference

Did I just record a solar flare, its imprint in some form, in the infrared oxygen triplet’s O I 7772 line? I think there is something in the data, I just don’t know what exactly.

Using a modified* Sol’Ex, I recorded the Sun at the infrared oxygen triplet, together with the neutral iron Fe I 7781. Passing clouds and some haze made the session less than ideal. The recordings have been reconstructed in JSolEx, and further processed with JSolEx’s ImageMath module.

The oxygen triplet lights up in an obvious manner near and beyond the disk edge, and prominences are visible after applying curves or subtracting a continuum from the disk at the wavelength. This is what I expected, based on what I read in the literature.

Between around 10:30Z-11:00Z, local time 12:30-13:00, there was a flare on the Sun, and for the second half of it, I recorded, still between the clouds.

blink compare: bad seeing and the clouds didn’t help

The average, showing O I 7771.954, O I 7774.17, O I 7775.39, Fe I 7780.568, and slit issues

oxygen lit up at/beyond the disk edge

oxygen lit up at/beyond the disk edge

Below two moments of the time series, UTC 2026-01-25 09:40 and UTC 2026-01-25 10:40, showing the clouds, and the disks with various processing methods, continuum subtraction, division by the continuum, log, etc. And reference images from GONG and SDO/AIA.

2026.01.25. 09:40 UTC the iron line

2026.01.25. 10:40 UTC the iron line

2026-01-25-0940 9-Sun-7772 2026.01.25. divi1Rot

2026-01-25-0940 9-Sun-7772 2026.01.25. dividaRot

2026-01-25-0940 9-Sun-7772 2026.01.25. lineDiviAvg

2026-01-25-0940 9-Sun-7772 2026.01.25. lineDiviMulRot

2026-01-25-0940 9-Sun-7772 2026.01.25. deltaPromLogRot

2026-01-25-1040 3-Sun-7772 2026.01.25. divi1Rot

2026-01-25-1040 3-Sun-7772 2026.01.25. dividaRot

2026-01-25-0940 9-Sun-7772 2026.01.25. kontinuumDiskRot

2026-01-25-0940 9-Sun-7772 2026.01.25. oxygenDiskRot

2026-01-25-1040 3-Sun-7772 2026.01.25. lineDiviAvg

2026-01-25-1040 3-Sun-7772 2026.01.25. lineDiviMulRot

2026-01-25-1040 3-Sun-7772 2026.01.25. deltaPromLogRot

2026-01-25-1040 3-Sun-7772 2026.01.25. kontinuumDiskRot

2026-01-25-1040 3-Sun-7772 2026.01.25. oxygenDiskRot

20260125093222Th gong

20260125104022Th gong

2026.01.25. 093348 1024 0094

2026.01.25. 104141 1024 1700

2026.01.25. 104151 1024 1600

2026.01.25. 104436 1024 0094

*grating switched to 1800 ln/mm instead of the stock 2400 grating; bandpass filters used for energy rejection, 62/400 scoped stepped down to ~42/400 by the 2″ full aperture bandpass filter

We are doing this, but in a lunch break. https://articles.adsabs.harvard.edu//full/1935KodOB…4..363R/0000389P000.html