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Progress Report for Adapting APASS Data Releases for the Calibration of Harvard Plates


Edward J. Los

Harvard College Observatory, 60 Garden Street, Cambridge, MA 02138

Presented at the 100th Annual Meeting of the AAVSO, October 8, 2011; received November 21, 2011; revised January 31, 2012; accepted January 31, 2012


The Digital Access to a Sky Century @ Harvard (DASCH) has scanned over 19,000 plates and developed a pipeline to calibrate these plates using existing photometric catalogues. This paper presents preliminary results from the use of the AAVSO Photometric All-Sky Survey (APASS) catalogue releases DR1, DR2, and DR3 for DASCH plate calibration. In the optimum magnitude 10–12 range of the DASCH patrol plates, the median light curve RMS with APASS calibration is 0.10–0.12 magnitude, an improvement from the 0.1–0.15 magnitude median light curve RMS with GSC 2.2.3 calibration.

link to article in ADS

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