1. European Organization for Nuclear Research Organisation Européenne pour la Recherche Nucléaire High-Energy Physics Data Delivering Data in Science ICSTI Winter Workshop Tim Smith – CERN/IT Department

2. Tim Smith @ ICSTI Workshop, Mar 2012 Delivering Data in HEP Data Storage and Stewardship Distribution and Access Interpretability, Reusability and Citability

3. Tim Smith @ ICSTI Workshop, Mar 2012 LHC and the Data Deluge 150 million sensors 40 million times /sec 22 PB in 2012

4. Tim Smith @ ICSTI Workshop, Mar 2012 4 Just a Drop in the Ocean! …Selection Particle Protons/bunch10 11 Crossing rate40 Million /sec Collision rate1 Billion /sec Parton (quark, gluon) Proton Bunch Filter to 200 /sec

5. Tim Smith @ ICSTI Workshop, Mar 2012 Data Storage 6 GB/s

6. Tim Smith @ ICSTI Workshop, Mar 2012 Data Stewardship: Migration LHC era 60 PB LEP era 100 TB

7. Tim Smith @ ICSTI Workshop, Mar 2012 Data Distribution & Access 11 T1 140 T2 T3s Worldwide LHC Computing Grid

8. Tim Smith @ ICSTI Workshop, Mar 2012 Data Access Publication data Derived physics data Analysis Object Data Reconstructed Data Raw Data / Simulated Data 70 PB Worldwide x N x tens x few 22 PB T0 T1 T2 T3

9. Tim Smith @ ICSTI Workshop, Mar 2012 Data Access ≠ Data Usability

10. Tim Smith @ ICSTI Workshop, Mar 2012 Data Reuse: Raw/Processed Data Reuse of the Reconstructed & Analysis Object Data –Calibrations, Configurations –Conditions DBs: tens of TBs –Reconstruction and identification algorithms –Detector response parameterizations –Software: millions of lines-of-code

11. Tim Smith @ ICSTI Workshop, Mar 2012 Data Reuse: Publication Data Published observables –Model-independent measurements –Distributions and cross-sections –HEPData: tabular –DOIs Rivet routines –Parameterize analysis acceptance –Compare simulated & measured data –http://rivet.hepforge.org/http://rivet.hepforge.org/

12. Tim Smith @ ICSTI Workshop, Mar 2012 Data Reuse: Derived Physics Data Access, ability to reinterpret –Reanalysis with new QCD calculations –Combination with data from future colliders –…serendipitous discovery Pitfalls: Large investment of effort required –Correlations, efficiencies, systematic uncertainties –Backgrounds estimated from data driven techniques Intertwined with event selection criteria Searches…

13. Tim Smith @ ICSTI Workshop, Mar 2012 Data Reuse: Derived Physics Data RECAST –Limits of an existing search for an alternative hypothesis –Brokering service –Collaboration Archives the analysis code Provides authority Digital Preservation in HEP –http://www.dphep.org/http://www.dphep.org/

14. Tim Smith @ ICSTI Workshop, Mar 2012 WLCG Delivering HEP data to scientists around the world

15. Tim Smith @ ICSTI Workshop, Mar 2012 Questions ?

16. Tim Smith @ ICSTI Workshop, Mar 2012 Abstract Particle accelerators such as the LHC generate an ever increasing flow of high-energy physics data. Each year the LHC experiments record large data sets which dwarf those of previous years. Moreover, with analysis teams around the globe, this data must be distributed worldwide for processing, reduction and near-time analysis. The challenges of managing and distributing this data deluge have been addressed by successive eInfrastructure projects over the years which have created and refined the Worldwide LHC Computing Grid. Tim will describe the way CERN data is stored and shared within the community, and touch on the challenges of expanding this outside for universal access and reuse.