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Feature Request: spectral lines

Open vnp85 opened this issue 9 months ago • 2 comments

I considered making this a pull/merge-request, but I am not sure what's your expected policy regarding merge-from-branches (squash or entire history with its garbage), and it would also be my first on github, so I'd possibly mess things up for you. Do you have a preferred method?

Anyways,

inside the file astro4j/jsolex/src/main/resources/me/champeau/a4j/jsolex/app/jfx/interesting-lines.txt parsed at https://github.com/melix/astro4j/blob/f47c85417e4d3424c1a89713800a28833aac5dc9/jsolex/src/main/java/me/champeau/a4j/jsolex/app/jfx/SpectrumBrowser.java#L722

according to the semicolon-separated header wavelength_angstrom;element_label;line_label;difficulty_zeroIsSimple

you have several interesting lines, and I would like to add to those. Here's why -- I caught proms, almost right after starting with Sol'Ex at "unexpected" wavelengths, and then studied the He I at 447.15nm, see among others (link 7 and link 8):

Image

Image

Rationale:

  1. I couldn't find a reliable atlas of the flash and prom spectrum. Maybe I am not looking for it the right way.
  2. The NIST spectral line catalog lists lines according to their inspection medium, not the Sun -- which results in the "relative intensity" column to be misleading for any solarist
  3. The literature cited on Bass2000 Solar Spectrum page (link 1), referencing (link 2) refer to the photosphere, which should be fine, but not one's first thought
  4. The monograph I found to be reliable for amateur work at least, is also very old, and I doubt many know about it, and it is rather manual, as it is a scanned book converted to pdf with some ocr (link 3)
  5. Sol'Ex brought these observations into the realm of amateurs like myself, no longer a Harvard question (link 4), see Table 3 in (link 5)
  6. The helium flash at 447.15 nm doesn't appear in either of the sources (link 2 and link3), but is studied in (link 5)

The additions I propose, albeit difficult, so marking with 4 and above, are well within our reach. He I at 447.15nm has been observed by an amateur with a different setup (link 6), inspired by my observations.

3829.365;Mg;Mg I;5

3832.310;Mg;Mg I;4

3838.302;Mg;Mg I;4

3859.922;Fe;Fe I;6

4471.5;He;He I;4

(link 1) https://bass2000.obspm.fr/solar_spect.php (link 2) https://bass2000.obspm.fr/download/solar_spect.pdf (link 3) https://nvlpubs.nist.gov/nistpubs/Legacy/MONO/nbsmonograph61.pdf (link 4) https://ui.adsabs.harvard.edu/abs/1964SvA.....7..643Y/abstract (link 5) https://articles.adsabs.harvard.edu/pdf/1964SvA.....7..643Y (link 6) nickname iulian90 at: https://www.astronomy.ro/forum/viewtopic.php?t=23724&postdays=0&postorder=asc&start=232 (link 7) https://www.asztrofoto.hu/galeria_image/1723760150 (link 8) https://www.asztrofoto.hu/galeria_image/1731324467

vnp85 avatar Mar 17 '25 11:03 vnp85

Hi! I'm happy with a PR. For such a thing a single commit should be good enough. Regarding the "score", the initial intention was to write some kind of "game" in the app to learn the spectrum, with increasing difficulty. I didn't get to it yet :) But it's also used to sort the lines in the selector.

melix avatar Mar 17 '25 17:03 melix

In the meanwhile I got into some even more weird lines. Maybe I need to refine my google skills, but I guess I went where no amateur has gone before. I need to think more about this.

vnp85 avatar Mar 22 '25 18:03 vnp85