NASAs ADS Abstract Service The Digital Library in

NASA’s ADS Abstract Service The Digital Library in Astronomy: An Example of a Worldwide Collaboration of Information Providers G. Eichhorn, A. Accomazzi, C. S. Grant, M. J. Kurtz, S. S. Murray Harvard-Smithsonian Center for Astrophysics 60 Garden Street Cambridge, MA 02138 USA gei@cfa. harvard. edu • 1

NASA’s ADS Abstract Service Overview • What is the Digital Library • ADS Data holdings • ADS Mirror sites • ADS Query example • ADS Usage patterns • Future plans • 2

NASA’s ADS Abstract Service Connectivity in the Digital Library • 3

NASA’s ADS Abstract Service History of the ADS • 1991: Classic ADS • 1993: Abstract Service • 1994: WWW Interface • 1995: Article Service • 5

NASA’s ADS Abstract Service What is the ADS today • Abstract search system with abstracts from various sources for journals, conference proceedings, technical reports, Ph. D theses, etc. Organized in 4 databases (Astronomy/Planetary Sciences, Physics/Geophysics, Instrumentation, Ar. Xiv Preprints) • Scanned journals and conference proceedings in Astronomy. Complete to volume 1 for many • 6 journals

NASA’s ADS Abstract Service Abstracts database • Astronomy/Planetary Sciences: 815, 000. Most journals complete to volume 1. • Physics/Geophysics: 1. 2 million. Complete Phys. Rev from volume 1. • Instrumentation: 630, 000, including SPIE • Ar. Xiv: All of the Ar. Xiv preprint database • 7

NASA’s ADS Abstract Service Scanned Articles • 2 million scanned pages in 280, 000 articles. – Most astronomy journals back to Vol. 1 • Historical literature: – 300, 000 scanned pages of historical observatory publications • 8

NASA’s ADS Abstract Service Links • 6. 8 million links – 3. 3 million external links – 3. 5 million internal links • Types of links – On-line journals – On-line data – References and citations • 9

NASA’s ADS Abstract Service Mirror Sites • USA • England • France • China • Japan • India • Chile • Russia • Germany • Brazil • 10

NASA’s ADS Abstract Service Mirror architecture • Sun/Solaris – 5 mirror sites • PC/Linux – 5 mirror sites • 11

NASA’s ADS Abstract Service Mirror Requirements • 25 Gb disk space (abstract service) • 400 Gb disk space (scanned articles) • 512 Mb RAM • 12

NASA’s ADS Abstract Service Query Examples • Query form • Query results • Also-read query • References • Citations • 13

NASA’s ADS Abstract Service Access Statistics • 60, 000 users/month • 1 million queries/month • 40 million records/month • 1. 4 million scanned pages/month • 290, 000 article requests/month • 37

NASA’s ADS Abstract Service ADS Usage by Region • 38

NASA’s ADS Abstract Service Future plans • More mirror sites • Stand-alone ADS – How to update them – Funding • 39

NASA’s ADS Abstract Service Access the ADS http: //ads. harvard. edu • 40