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Differential Ensemble Photometry by Linear Regression

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Kevin B. Paxson
20219 Eden Pines, Spring, TX 77379

Received January 20, 2010; revised January 22, 2010; accepted January 25, 2010

Abstract A linear regression method for multiple star ensemble photometry by
spreadsheet is presented. After initial spreadsheet setup and data entry, a
differential ensemble magnitude estimate is calculated along with a total error.
Ensemble photometry by linear regression allows one to see the distribution of
comparison star errors, yields variable star estimates with enhanced confidence,
and identifies potential problems with the comparison stars, validating the
Johnson V magnitude sequence. Spreadsheet construction is described and two
linear regression ensemble examples are illustrated and discussed.

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