CERNLIB

CERNLIB
Name	CERNLIB
Developer	CERN
Released	1970s
Latest release	1990s
Programming languages	FORTRAN
Operating system	Unix, VMS, Microsoft Windows
Genre	Scientific library

CERNLIB is a collection of physics-oriented software libraries developed at CERN for use in particle physics experiments and data analysis. The project provided numerical, mathematical, histogramming, input/output and detector-simulation tools used by collaborations at facilities such as CERN, Fermilab, DESY, SLAC, and KEK. Originally assembled during the 1970s and maintained through the 1990s, the suite supported major experiments at the Super Proton Synchrotron, LEP, and early LHC efforts.

History

CERN engineers and physicists began assembling reusable code during the 1970s to support detectors in projects at CERN and cooperating laboratories such as BNL and TRIUMF. Influential figures and groups at CERN coordinated versions, aligned with standards from EDM initiatives and collaborated with teams from SLAC and DESY on portability. Over time, stewardship shifted as software engineering practices evolved alongside work at LEP experiments like ALEPH and DELPHI, and as projects such as ROOT and Geant4 emerged from communities including CERN and CERN openlab. The suite was gradually deprecated in favor of object-oriented systems developed during the 1990s and 2000s, paralleling transitions at LHC collaborations and research centers like Fermilab.

Components and Libraries

The collection included foundational modules widely used by collaborations such as ATLAS and CMS before their migrations. Key components comprised: - Mathematical libraries derived from algorithms used at CERN and influenced by work at NAG and contributions from researchers associated with DESY and KEK. - Histogramming and data-analysis packages analogous to tools later found in ROOT and used by experiments at LEP and SPS. - Input/output and file-format utilities enabling interoperability with standards supported by CERN computing centers and partners like SLAC and Fermilab. - Detector-simulation interfaces that prefigured concepts implemented in Geant3 and later in Geant4, used by collaborations such as ALEPH and L3. - Graphics and visualization modules that interworked with plotting systems developed at CERN and laboratories including DESY.

These modules were integrated into experiment-specific frameworks for projects run by institutions like Oxford University, University of Cambridge, Imperial College London, and national labs including BNL.

Software Architecture and Languages

The codebase was primarily written in FORTRAN, following conventions used in scientific computing at CERN and partner institutions such as SLAC and DESY. Interfaces bridged to C and later to object-oriented systems influenced by developments at CERN and research groups at LAPP and INFN. The architecture favored modular libraries with well-specified APIs to permit reuse across experiments like NA49 and WA97, and supported procedural programming idioms common in collaborations at Fermilab and KEK. Build and distribution practices aligned with standards adopted by computing centers at CERN and community-driven efforts involving groups at UC Berkeley and University of Manchester.

Platforms and Compatibility

Binaries and source were produced for operating systems used by research facilities: Unix variants prevalent at CERN and SLAC, VMS at legacy installations including BNL, and later ports to Microsoft Windows for desktop analysis at universities like Oxford and Cambridge. Compatibility layers accommodated compilers from vendors used by laboratories such as IBM and Hewlett-Packard and integrated with batch systems at computing centers including CERN’s central services. The portability strategy mirrored efforts by institutions such as DESY and FNAL to enable distributed analysis workflows across heterogeneous clusters.

Usage in High-Energy Physics

Researchers at experiments like ALEPH, DELPHI, L3, UA1, and UA2 relied on the libraries for reconstruction, calibration, and statistical analysis. Graduate students and postdocs from universities including University of Oxford, University of Cambridge, ETH Zurich, and University of Tokyo used the suite in data reduction pipelines interfacing with services at CERN and Fermilab. The tools supported workflows connecting detector readout systems at facilities such as SPS to analysis clusters managed by groups at DESY and SLAC, and formed the backbone of many pre-ROOT analysis chains.

Legacy and Succession

The decline of the suite mirrored the rise of object-oriented frameworks developed by communities around CERN and institutions such as LAL and INFN. Successor projects included ROOT and Geant4, which were adopted by experiments at LHC and laboratories like Fermilab and KEK. Historical influence persisted in numerical algorithms preserved in repositories maintained by groups at CERN and archiving efforts by national labs including BNL and DESY. Academic programs at universities such as Imperial College London and University of Manchester document migration paths from the legacy suite to modern frameworks.

Documentation and Support

Documentation was provided through technical notes, user guides, and contributions from support teams at CERN and collaborating centers like SLAC and DESY. Training and local support came from computing groups at universities including Oxford University and University of Cambridge and from national labs such as Fermilab and BNL. As official maintenance ceased, community archives and institutional mirrors at places like CERN and DESY continued to host manuals and example code used by historians of computing and researchers migrating legacy analyses.

Category:Physics software CERN