Paschen Gamma (enhanced) Solar Disk
Using the purpose built spectroheliograph, with stacked filters of 1075nm/50nm and 1100nm/50nm, I observed the Paschen gamma line (λ 10938.1Å), hoping to extract Hydrogen-resembling disk details. Neither the seeing, nor the low winter Sun helped the observation, worsening the already challenging endeavor. For this observation, I used the IMX 585MM camera, instead of the 678MM, hoping to get more photons per pixel, sacrificing some spectral resolution — mixed results.
Still, the image published here, with the signal enhanced, could well be the very first Paschen Gamma Solar Disk, bringing the details to life.
The line itself is much weaker than the He I D3, it is a nebulous blur on the spectrum on the disk center, and is dwarfed by He I 10830 in the flash spectrum. In this respect, it resembles the situation of the (Balmer) epsilon line, which is overwhelmed by the calcium valley, or that of the He I D3 which is somewhat subtly visible while scanning, and is fully revealed only through continuum subtraction.
gong Ha, for reference
my observation, He I 10830, continuum subtracted, for reference
my observation, Balmer epsilon, continuum subtracted, for reference
spectra
the chosen continuum
continuum with gamma
continuum with wavelets
reconstructed PG wavelength
a gamma curve reveals some hydrogen features
wavelets emphasize the weak hydrogen features
And below a table with the hydrogens observed during this session
epsilon prime
gong Ha
Paschen Gamma (enhanced) Solar Disk
