Remarks on statistical errors in equivalent widths

Abstract

Equivalent width measurements for rapid line variability in atomic spectral lines are degraded by increasing error bars with shorter exposure times. We derive an expression for the error of the line equivalent width $\sigma (W_{\lambda })$ with respect to pure photon noise statistics and provide a correction value for previous calculations.

4 pages, 1 figure, accepted by Astronomical Notes

Cited by in corpus (78)

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