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Lick Northern Proper Motion Program. III. Lick NPM2 Catalog

Robert B. Hanson·Arnold R. Klemola·Burton F. Jones·David G. Monet
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Abstract

The Lick Northern Proper Motion (NPM) program, a two-epoch (1947-1988) photographic survey of the northern two-thirds of the sky (Dec. > -23 deg), has measured absolute proper motions, on an inertial system defined by distant galaxies, for 380,000 stars from 8 14) anonymous stars for astrometry and galactic studies, 92,000 bright (B < 14) positional reference stars, and 35,000 special stars chosen for astrophysical interest. The NPM2 proper motions are on the ICRS system, via Tycho-2 stars, to an accuracy of 0.5 mas/yr in each field. RMS proper motion precision is 6 mas/yr. Positional errors average 80 mas at the mean plate epoch 1968, and 200 mas at the NPM2 catalog epoch 2000. NPM2 photographic photometry errors average 0.18 mag in B, and 0.20 mag in B-V. The NPM2 Catalog and the updated (to J2000) NPM1 Catalog are available at the CDS Strasbourg data center and on the NPM WWW site (http://www.ucolick.org/~npm). The NPM2 Catalog completes the Lick Northern Proper Motion program after a half-century of work by three generations of Lick Observatory astronomers. The NPM Catalogs will serve as a database for research in galactic structure, stellar kinematics, and astrometry.

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Robert B. Hanson, Arnold R. Klemola, Burton F. Jones, David G. Monet. 2004-06-07. Lick Northern Proper Motion Program. III. Lick NPM2 Catalog. https://doi.org/10.1086/423041

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