| | 1 | == Star / Galaxy / CR Separation in PS1 == |
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| | 3 | -- Eddie Schlafly & Eugene Magnier |
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| | 5 | We have used GPC1 observations of Stripe 82 to define the PS1 Star / Galaxy / CR separation. The advantage of this region is that SDSS data exists for both single pass and deep stack analysis. |
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| | 7 | We looked at several parameters measured by the IPP psphot tool which may be sensitive to the difference between stars and galaxies. We used the SDSS star/galaxy separation from both the single pass and the deep stack images as 'truth'. Our main conclusion is that a simple comparison between the PSF and Kron magnitudes for objects does a good job of reproducing the SDSS star/galaxy separation for signal-to-noise > 10.0 For signal-to-noise between ~6.5 and 10.0, the two populations start to blurred together significantly. For S/N < 6.5, we are unable to distinguish stars and galaxies. |
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| | 9 | We found that the moments did not improve the star/galaxy separation. Instead, because of the variable PSF, including moment information tended to increase the noise in the measurement. |
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