140 likes | 264 Views
Object Oriented reconstruction of the CMS muon chambers. CHEP 2000 7-11 February, Padova. Annalina Vitelli - INFN Torino. Items. The CMS Muon Chamber Detector What the software has to do? A glance to the past ... Software design First applications Conclusions.
E N D
Object Oriented reconstruction of the CMS muon chambers CHEP 2000 7-11 February, Padova Annalina Vitelli - INFN Torino
Items • The CMS Muon Chamber Detector • What the software has to do? • A glance to the past ... • Software design • First applications • Conclusions
The CMS Muon Chamber Detector • Muon Identification • Muon Trigger • p measurement • ...
What the software has to do? • GEANT Hits access • Digitization: detector response (time) • Calibration :time-space conversion • Local reconstruction :reconstruction of track segments inside a chamber • Standalone fit: p measurement using only the muon system
A glance to the past ... • September 1998: ORCA_1 release • GEANT3 access (geometry+hits) • digitization • local reconstruction • April 1999 : ORCA_2 release • complete integration to CARF • first track fit prototype • November 1999 : ORCA_3 release • first experience with a Objectivity DB • extensive application of the "on demand" CARF mechanism
The Software design This section could be called: The Muon Chamber & The TrackFinder an example of OO A&D process
The way we proceed is: Build the model describing a scenario • find the basic objects • identify their responsibilities • define the relations among objects
The scenario:find a track from a defined seed Starting from the first layer, then: • find the compatible DetUnit in this layer • for each DetUnit check the compatible clusters • add the best cluster to the track • go to the next layer if no cluster are found restart from the next layer
Who? • Digitization and local reconstruction should be provided by the chamber • the output of the local reconstruction are objects "detachable" from the detectors • these objects are used to perform physics reconstruction and the analysis of the "Event"
How? Looking at the chamber: • we want to be fast! • we want clusterize, digitize etc. , just the interesting stuff • at next step we don't want to re-compute what has been done before • ...
The Chamber (detector reconstruction level) SimHitLoader Detector Element The three actions under the chamber responsibility are done only on demand Digitizer Chamber Local reconstruction
Track Finder(event reconstruction level) User The fit is performed only on demand The regional reconstruction can be easily provided using the navigability of the DetUnit and the "on demand" reconstruction mechanism Event Tracks Rec<Tracks> Detector Element Rhit
First applications • The first application of the OO reconstruction package was the analysis of the data taken in the August 1999 test beam • in November 1999 a production of Monte Carlo events was performed using the digitization software to store the data in a objectivity DB, and the reconstruction packages to provide the muon tracks fit
Conclusions After 1.5 year the muon software has been done with most of the requested functionalities The "on demand" mechanism was clearly useful to solve most of our requirements The extensive use of the code allowed to test, besides its performances, the versatility and the handiness of the software!