Jun 7, 2012

More Automated Distance-Finding for Leo IV

Left plot:
Distance modulus versus # stars selected. The yellow line at 750 stars represents the cutoff point; distances which select fewer stars are not included on the right plot (i.e, y-axis values set to zero). This minimum value is chosen to reduce the impact of very small populations on the final distance estimated. It is not a great solution, but in this case it does improve the results.

Right plot: 
Distance modulus versus # max-density (color=255) bins. The distance with the maximum y-value on this plot is returned as the estimated distance.

In this case, this algorithm returns 21.5 as the estimated distance modulus. Actual distance modulus: 20.98 (according to NED). 

Ideally the algorithm should return 21.0 as the estimated distance. This requires a more effective way of quantitatively valuing the different distances. 

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