RAVE – a detector-independent vertex reconstruction toolkit W. Waltenberger, F. Moser, W. Mitaroff Austrian Academy of Sciences Institute of High Energy Physics, Vienna A detector-independent toolkit for vertex reconstruction (RAVE) is being developed, along with a standalone framework (VERTIGO) for testing, analyzing and debugging. Main design goals are ease of use, flexibility for embedding into existing software, extensibility, and openness. A beta release is available. Motivation and goals Track and vertex reconstruction must not compromise the high spatial resolution of modern semiconductor detectors. This goal can be achieved by new, sophisticated methods beyond the traditional least squares or Kalman filter estimators, using robust, non-linear adaptive algorithms. The early stages of data analysis – local pattern recognition, track search and track fitting – are highly detector-dependent, and their software is usually coded from scratch. The next stage – vertex reconstruction – is, however, almost fully detector-independent, and re- coding may be avoided if there exists an adequate, reliable and easy-to-use software toolkit. Such a toolkit should collect the world-best algorithms available for vertex reconstruction, i.e. finding, fitting and kinematics. Its implementation should make extensive use of open standards. Acronyms RAVE = “reconstruction (of vertices) in abstract versatile environments”, VERTIGO = “vertex reconstruction toolkit and interfaces to generic objects”. The RAVE / VERTIGO project 1.Development of an extensible, detector-independent toolkit (RAVE) for vertex reconstruction, to be embedded into various environments: RAVE includes the core algorithms for both vertex finding (a pattern recognition task a.k.a. track bundling) and vertex fitting (estimation of the vertex parameters and covariance matrix). Starting point was the CMS offline reconstruction software (ORCA), coded in C++, which has recently been refactored and ported to a new framework (CMSSW). Principal assets are robust reconstruction algorithms with estimators based on adaptive filters, thus downweighting the influence of “outliers” (tracks not belonging to the vertex being fitted). Thanks to its generic API, the toolkit may easily be embedded into the software environments of various experiments (e.g. CMS at LHC, LDC and SiD at ILC, BELLE at KEKB). 2.Development of a simple standalone framework (VERTIGO) for fast testing, analyzing and debugging of the core algorithms: Framework tools available: visualisation, histogramming, “vertex gun” for artificial events, LCIO input interface, and “data harvester” (abstract persistency solution) for flexible I/O. Emulation of various detector setups is supported by the “skin” concept, introducing an experiment-specific intermediate layer between the RAVE core and VERTIGO. VERTIGO event loop diagramRAVE class diagram (vertex factory) VERTIGO class diagram (event generator)VERTIGO class diagram (observer) VERTIGO functionality Embedding RAVE into non-CMS softwareVERTIGO emulating detector setups Status: Full CMS skin (“native”, i.e. no parameter conversions needed): tested, served as a test bed as long as CMSSW was not fully operational; Simple LDC and SiD skins (no materials): tested, with input from LCIO (switch for standard “L3” or temporary “Brahms” track representations). Status: Fully tested within the “native” new CMS software framework (CMSSW); Finished for C++ environments; tested with MarlinReco/Marlin (temporary solution for “Brahms” track fit parameters and covariance matrix); Java 5 environments need C++ wrapper (SWIG): first tests with org.lcsim. Visualisation of adaptively fitted c-cbar and b-bbar events (simulated for CMS) Outlook 1.Near future: Interfacing RAVE with the ZvTop (topological vertex search) algorithm: developed for SLD at SLC, at present re-coded in C++ (by RAL) and Java (by SLAC); Embedding RAVE into the new Marlin version (standard “L3” track representation); Refinement of the VERTIGO skins for the LDC and SiD detectors at ILC; Embedding RAVE into the org.lcsim (Java based) ILC reconstruction software by means of a C++ wrapper (SWIG). 2.Mid-term future: Augmenting RAVE with the CMS kinematics fitting and b-tagging algorithms; A simple VERTIGO skin for the BELLE detector (“Panther” track representation); Embedding RAVE into the BASF (C++ based) BELLE reconstruction software. 3.Long-term future: Re-coding of RAVE in Java 5, if the C++ wrapper solution proves inefficient. 4.Maintenance and development: We are committed to maintenance, documentation and distribution of RAVE and VERTIGO. A WebSVN repository exists, containing our beta release. 5.Where to look:  Analysis Tools  RAVE/VERTIGO thread;