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Background Subtraction

  • Page ID
    76353
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    All atom reservoirs emit some continuum radiation, and many also emit background lines due to the gases supporting flames or plasmas. In the simplest, linear cases, Iobs, the total observed intensity, is Iatom + Ibkrnd, the intensity of atomic emission from the species of interest plus the intensity of background continuum emission. By measuring emission from line + background, measuring background with the same bandwidth in an adjacent, line-free fregion, and taking the difference, the light due just to the species of interest can be obtained. If there is structure to the background (diatomic molecule emission or emission from a gas atom), one may need to scale the background so that Iatom = Iobs - k × Ibkrnd, where k is experimentally determined to optimize precision of determinations. Such subtraction is frequently employed together with other data reduction approaches.

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    This page titled Background Subtraction is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Alexander Scheeline & Thomas M. Spudich via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.