The Babar experiment, or simply Babar, is an international collaboration of more than 500 physicists and engineers located at the SLAC National Accelerator Laboratory, which is operated by Stanford University for the Department of Energy in California.

It was set up in 1999 to understand the disparity between matter and antimatter in the universe. The BaBar detector ceased operation on 7 April 2008.

Bit Preservation: 

2.7PB of data of which 2PB (budget constraints) will be migrated to new media when supported by SLAC


Data is stored on tape at SLAC and CC-IN2P3 (back-up only); Active data on disk accessed via xrootd.


All the most used and fundamental information have been checked, updated and moved to a Media Wiki server, the BaBar WIKI. Internal documents are stored on disk and backed up on tape and are accessible to the Collaboration via web applications. All published papers are available through the BaBar web and arXiv/inSPIRE.


Software releases: C++ Object Oriented 32 bit. They build and run on SL4, SL5, SL6 32 and 64 bit (or corresponding RH). Other software: Tcl, Perl, Phyton, SQL (MySQL, Oracle). Software releases, even in frozen virtual environment, still preserve their full capability to handle data processing, data analysis, and future extensions (new analyses, new physics models).

Use Cases: 

Continued analyses by BaBar Collaboration members.


Primarily the BaBar Collaboration.


Quantitative measures (# papers, PhDs, etc.) exist.

More than 30 analyses are on track for publication, about 20 have less clear future.


Data will not be superseded by LHC – some by Belle II (for example, not the Y(3S) data sample).


0.35 FTE computing support for BaBar at SLAC by end 2015


The BaBar Collaboration is still very active and engaged even if resources are dwindling.


Much of the hardware is aging; Sun OS 5.10 support will stop at SLAC within 2 years and corresponding h/w will be decommissioned


Aim to preserve data for on-going analyses until 2018 with extension to 2020+ to match Belle II schedule.

The technology at the base of the future operating model will be virtualization – all the services now running on physical hardware will soon run on virtual machines

Host Lab: 

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