Optimal proper motion measurements with the Wide Field and Planetary Camera
نویسندگان
چکیده
An optimal maximum-likelihood technique for computing point-source image centroids from many, slightly o set, CCD frames is presented. The method is especially useful for measuring stellar proper motions from data taken with the Wide Field and Planetary Camera aboard the HST, and also provides a means to identify very compact non-stellar sources. We work though the example problem of obtaining image centroids of objects in the Hubble Deep Field. Subject headings: astrometry | stars: kinematics | Galaxy: kinematics and dynamics
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تاریخ انتشار 1998