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Cataloging the Northern Sky Using a new Generation of Software Technology

Weir, N. and Djorgovski, S. and Fayyad, U. and Smith, J. D. and Roden, J. (1994) Cataloging the Northern Sky Using a new Generation of Software Technology. In: Astronomy from Wide-Field Imaging. International Astronomical Union. No.161. Springer , Dordrecht, pp. 205-212. ISBN 978-0-7923-2879-7.

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We have developed a system, called SKICAT, for producing, managing and analyzing catalogs from the digitized POSS-II survey. The system classifies and matches catalogs from multiple, overlapping plate scans as well as CCD calibration sequences; and it can be used for the scientific analysis of the resulting catalogs. It incorporates a number of novel machine-learning and AI tools, including the star/galaxy classification using decision tree algorithms. This results in star/galaxy separation accurate to 90% or better down to B_j, ∼ 21^m, i.e. ∼ 1^m above the plate limit The final catalog is expected to contain at least 5 x 10^7 galaxies and > 2 x 10^9 stars. We present preliminary results on galaxy counts from a test region near the NGP. We find a mild excess over the no-evolution models, smaller than previously found by the APM group. A search for z > 4 quasars and the two-point correlation analysis of this data set are in progress.

Item Type:Book Section
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URLURL TypeDescription ReadCube access
Djorgovski, S.0000-0002-0603-3087
Smith, J. D.0000-0003-1545-5078
Additional Information:© 1994 Springer Science+Business Media Dordrecht. This work: was supported at Caltech in part by the NASA AISRP contract NAS5-31348, Caltech President's fund, and the NSF PYI award AST-9157412, and at the JPL under a contract with the NASA. The POSS-II is partially funded by grants to Caltech from the Eastman Kodak Co., the National Geographic Society, the Samuel Oschin Foundation, the NSF grants AST 84-08225 and AST 87-19465, and the NASA grants NGL 05002140 and NAGW 1710. We acknowledge the efforts of the POSS-II team at Palomar, and the scanning team at STScl. We thank the conference organizers for a partial travel support, and an enjoyable meeting.
Funding AgencyGrant Number
Caltech President’s FundUNSPECIFIED
Eastman Kodak CompanyUNSPECIFIED
National Geographic SocietyUNSPECIFIED
Samuel Oschin FoundationUNSPECIFIED
NSFAST 84-08225
NSFAST 87-19465
NASANGL 05002140
Subject Keywords:Decision Tree Algorithm; Stellar Object; Decision Tree Induction; Plate Scan; Object Catalog
Series Name:International Astronomical Union
Issue or Number:161
Record Number:CaltechAUTHORS:20190724-084632067
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:97382
Deposited By: Tony Diaz
Deposited On:24 Jul 2019 16:25
Last Modified:12 May 2020 21:41

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