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Atlantis tutorial. Jon Couchman (UCL), Hans Drevermann (CERN), Gary Taylor (UCSC). Atlas software week/CERN. 16 May 2003. Outline. Introduction Data visualization – Hans Drevermann Basic concepts (presentation) Hands on demonstration of basic functionality User session
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Atlantis tutorial Jon Couchman (UCL), Hans Drevermann (CERN), Gary Taylor (UCSC) Atlas software week/CERN 16 May 2003
Outline • Introduction • Data visualization – Hans Drevermann • Basic concepts (presentation) • Hands on demonstration of basic functionality • User session ---- Coffee ---- • Advanced features (presentation) • Hands on demonstration of advanced features • User session • Access to events – Jon Couchman • Questions & answers
Atlantis goals Primary • visual investigation and physical understanding of complete Atlas events. Secondary • help develop reconstruction and analysis algorithms • debugging during commissioning • pictures and animations for publications, presentations and exhibitions • event display for simple test-beams • online event display
Data The following data may currently be visualized by the program • 3D silicon points, silicon strip clusters and TRT straws • Simulated tracks, neutral particles and vertices • Reconstructed tracks iPatRec, xKalman • Hit-to-track associations (kine, iPatRec only) • Reconstructed secondary vertices • LAr, TILE, HEC and FCAL calorimeter cells and clusters. • MDT, RPC, TGC, CSC hits and CSC clusters • Simulated and reconstructed muon tracks (MOORE)
Detector/Data oriented projections 3D Cartesian coordinates x,y,z are not always optimal for colliding beam experiments More natural and useful are the non-linear combinations which reflect the design of ATLAS r = (x2+y2), f = atan2(y, x), h = log( z/r + ((z/r)2+1) , where x, y, z need to be slightly modified to take into account the primary vertex of the underlying event (xvtx yvtx zvtx ) x' = x-xvtx , y' = y-yvtx , z' = z-zvtx
f/r projection – like Y/X, butprompt tracks are straight lines
r/Z projection – calorimeters, muon hits (rsector) (intuitive)
X'/Z projection – muon hits and their association to Moore tracks
f/Z projection – TRT and LAr endcaps, HEC, TGC phi strips TGC TRT
f/h projection and the V-Plot r = rMax V-Plot • Draw each space point twice at • F,h+k*(r-rMax) • and • F,h-k*(r-rMax) • 3D information • For tracks can judge • f • h • pt (slope of V arms) • charge ( L -ve • V +ve) f low p, -ve r = 2 cm h Distorted V’s track not from IP high p, +ve
f/h projection – track to calorimeter associations (30 GeV electron) LAr Presampler Pt=29.3 GeV E =31.2 GeV Cell geometry LAr Layer 2 LAr Layer 3 LAr Layer 1 Track (enters LAr here) Area a E Island (guides eye)
User interface Window Control (zoom,copy, DnD) Menu bar (IO,preferences,help) Interaction Control Commands Projections Parameters Parameter groups Output window
Online help – available for every component Hover for tool-tip help Right click on component for online help (hyper-linked HTML)
Interactions • ZMR - zoom, move and rotate w.r.t defined center • Rubberband - selection and zooming • Pick - pick and move to (selection and query) • Fisheye - relative expansion of central region • Clock - relative expansion of angular region • Synchro-cursors - correlation between different projections • Scale - copy scales between windows Mostly mouse driven with sometimes a modifier key pressed on the keyboard
Input Data Atlantis is a JAVA application It communicates with Athena via dedicate XML files produced by JiveXML ( see talk by J.Couchman) These files are best grouped and compressed inside zip files Single design luminosity event is approx 20 MB (XML) 4 MB (zip)
Detector Geometry • Used to convey quickly to the user the context in which hits are to be viewed. • Idealized geometry is adequate and desirable. (e.g. LAr pre-sampler is only 1 cm thick and would be invisible if drawn as such • Stored in two separate XML files. • muon geometry derived from parameter book.
Printing File => print => EPS, PNG, GIF EPS – high quality vector graphics good for posters, publications (file size 200KB - 2MB) PNG – compressed bitmap good for ppt presentations + web (file size 20-50 KB)
Web page • www.cern.ch/atlantis • How to download, install and run Atlantis • Picture database (example event displays) • Presentations
Contibutors Many people contributed to the development of Atlantis. In particular Gary Taylor (UC Santa Cruz) Principal developer Hans Drevermann (CERN/EP) Original ideas, FORTRAN version Dumitru Petrusca (Siegen/CERN) Initial work on GUI, calorimeters Jon Couchman (UCL) Athena algorithm (JiveXML) Frans Crijns (Nijmegen) Muon geometry Peter Klok (Nijmegen) Picture database
Atlantis tutorial-2 Jon Couchman (UCL), Hans Drevermann (CERN), Gary Taylor (UCSC) Atlas software week/CERN 16 May 2003
Analysis Techniques Data to be viewed may be Cut - e.g. by pT, energy, association… Colored - by associations , layer, sub-detector more powerful when used in combination e.g. selected only hits belonging to kine tracks and color them by their associated reconstructed track ( inconsistencies indicate problems) Superimposed – iPatRec tracks over true tracks
Check track reconstruction in difficult design luminosity event • Selected event has two high pt (>560GeV) jets ( DC1dataset 2045) • Luminosity 1034 • Silicon space points 27,000 • TRT hits 240,000 • Reconstructed tracks 1,200 • Reconstructed in 20 minutes
2D projections of Inner Detector data not very useful at design luminosity (TRT -ve barrel only)
V-Plot silicon space points Fh calorimeters
Filtering of space points available inside Atlantis Filter space points with a histogram based technique which selects hits consistent with tracks originating from the primary vertex. Time = 1 sec/event ATLAS note in preparation
Filtered hits iPatRec tracks True tracks 34 tracks 410 GeV 236 tracks 440 GeV 25 tracks 222 GeV 27 tracks 270 GeV
Tracks lost in core of central jet iPat,S3D(Filter,iPat) STr,iPat,S3D(STr,iPat) iPat, xKal
Lists Up till now we have seen how to investigate data and association present on the input file. Lists allow user to dynamically create and manage their own associations grouping of object perform context dependent operations e.g. vertex a set of reconstructed tracks
Identifying secondary vertices Look for a group of nearby kinked V’s in the VPlot True tracks Reconstructed tracks D B
Y/X projection – region around the primary vertex • Region around primary vertex B D 3s error ellipse Primary Reconstructed tracks True tracks
Secondary vertex region best displayed in abstract 3D Box Ellipses represent track error (1s) Plane containing primary vertex Plane containing secondary vertex secondary vertex primary vertex
Space point formation from silicon strip clusters v-strip S3D missing? f-strip u-strip iPatRec track 50 mm S3D (pixel)
Comparison of muon and inner detector track fits f p = 28 GeV Dp = 5 GeV Df = 1.5 deg Dh = 0.02 muon tracks Inner detector tracks p = 25 GeV Dp = 4 GeV Df = 1 deg Dh = 0.01 V-Plot allows comparison of f, h and pt h
Cell clustering and Jet reconstruction – AtlFast (DC1- QCD event) Details of cell clustering Cells coloured by cluster (Area a E) Jet (Area a E) ? E= 13 GeV SE= 347 GeV Bug ?
Contibutors Many people contributed to the development of Atlantis. In particular Gary Taylor (UC Santa Cruz) Principal developer Hans Drevermann (CERN/EP) Original ideas, FORTRAN version Dumitru Petrusca (Siegen/CERN) Initial work on GUI, calorimeters Jon Couchman (UCL) Athena algorithm (JiveXML) Frans Crijns (Nijmegen) Muon geometry Peter Klok (Nijmegen) Picture database