pan-starrs image processing pipeline
DESCRIPTION
Pan-STARRS Image Processing Pipeline. Astrometry and Photometry. IFA Pan-STARRS Seminar 735. October 14, 2004. Summary of Topics. Astrometry and Photometry Precision Requirements Summary of the AP Survey Achieving the Photometry Goals Achieving the Astrometry Goals. - PowerPoint PPT PresentationTRANSCRIPT
Pan-STARRS Seminar: IPP Eugene Magnier
IFA Pan-STARRS Seminar 735October 14, 2004
Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
● ●galaxy cluster evolution●rare object searches
●high-z QSOs●extremely red galaxies●low-mass objects (L & T dwarfs)●YSOs
Pan-STARRS Seminar: IPP Eugene Magnier
Pan-STARRS Seminar: IPP Eugene Magnier
●linearize detector flux●apply shutter correction●flatten images●photometer objects●apply image zero point, color correction, airmass correction
Pan-STARRS Seminar: IPP Eugene Magnier
●stable light source + variable exposure time?●calibrated light source?
Pan-STARRS Seminar: IPP Eugene Magnier
●measure shutter fly-over times: dt(x,y)●apply to flat-field or science images●probably small for 30 second exposures (0.1% = 30 ms jitter●may be significant for 5 second exposures...
Pan-STARRS Seminar: IPP Eugene Magnier
●twilight-flat
●pros: continuum source, spatially uniform (usually), bright ●cons: very blue, limited availability, cirrus issues
●dome-flat●pros: continuum source, available anytime, repeatable (?)●cons: spatial structures, low count rates, emission line dangers
●night-sky flat●pros: obtained 'automatically'●cons: low count rates, stellar contaminations,
spatial structures unknown, emission line source
Pan-STARRS Seminar: IPP Eugene Magnier
●correct for geometrical distortion & scattered light●stability time scale?
Pan-STARRS Seminar: IPP Eugene Magnier
●chip-to-chip color terms (possibly linear, small)●internal system vs external system●external transformations are often ambiguous
Pan-STARRS Seminar: IPP Eugene Magnier
●use relative photometry with reference overlaps●measure zero points & atmospheric corrections, apply●combination method (relphot + uniphot)
Pan-STARRS Seminar: IPP Eugene Magnier
●system zero-points vary ~0.1 mag on timescales ~ 100 days
Pan-STARRS Seminar: IPP Eugene Magnier
●variations in time : Cf(t)●variations in space : Cf(ra,dec)●these variations are NOT strongly correlated
Pan-STARRS Seminar: IPP Eugene Magnier
Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
● ●high-quality grid for weak-lensing (starting point)●stellar matching in crowded fields
Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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Pan-STARRS Seminar: IPP Eugene Magnier
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