4 ms·

"FE I remains undetected" Remains Undetected. Pretty crystal clear.

• ccgreg 1y ago
  No. Undetected iron and zero iron are different. Source: astronomer.
  • galacticaactual 1y ago
    "Undetected" is not an "upper bound." Source: computer scientist.
    • ccgreg 1y ago
      Undetected means you can compute an upper bound, based on the performance of your instrument. Again, these are undergraduate level concepts.
      • galacticaactual 1y ago
        Again, you’re being obtuse but well leave it there. Good day.