... cluster

Table 3 is only available in electronic form at http://www.edpsciences.org

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... 2000)

The HST mosaicked ``master'' images of the Orion Nebula are accessible at http://casa.colorado.edu/~bally/HST/HST/master/

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... IRAF

IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.

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... stars

The correlation coefficient r is a measure of the linear association between variables. The strength of this association is sometimes expressed as the square of the correlation coefficient. The resulting statistic is known as variance explained. For example, a correlation of 0.5 means that (0.5)² or 25% of the variance in Y is "explained'' or predicted by the Xvariable. This parameter is used throughout this paper.

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...(1997)

http://www.astro.caltech.edu/~lah/papers/orion_main.table1.working

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