20041221 umwlap001 05 vassilakoopoulos

Graviton production and decay in warped extra dimensions: 

Graviton production and decay in warped extra dimensions V. Vassilakopoulos for the Hampton University ATLAS Group North American ATLAS Physics Workshop, Tucson, AZ, Dec 19-21, 2004

Objectives: 

Objectives Perform the full simulation in ATLAS of graviton production and decay in warped extra dimensions according to Randall & Sundrum model: Phys. Rev. Lett. 83, 3370 (1999) g+gG* l+l- or g+g G* Z0 Z0 f+fG* l+l- or f+f G* Z0 Z0 Using implemented branching ratios as in Pythia v6.221 Do analysis using Physics Analysis Tools.

Signal Issues: 

Signal Issues Signal handles Expect a narrow resonance (TeV scale) Maybe an isolated one… Angular distribution for spin-2 particles A displaced vertex ; it should suppress the background. Will not discuss on this talk. Decay to SM particles.

Simulation Environment: 

Simulation Environment Using Release 9.0.2 Events generated with Pythia v6.221 Graviton mass set to 1 TeV (pythia def.) Checkout packages: SimulationOptionsRome Digitization-00-06-05 AnalysisExamples-00-08-05 RecExCommon-00-02-87

Full Simulation Flow: 

Full Simulation Flow Event generation (evgen.root) G4 simulation (g4sim.root) Digitization (digit.root) ESD creation from RDO (ESD.root) AOD creation from ESD (AOD.root) Root tree and Histos from AOD (Gee.hist.root, Gee.ntuple, etc.)

Event Generation (1): 

Event Generation (1) For G*e+e- Pythia.PythiaCommand += [ "pysubs msel 0", #sub processes must be explicitly switched on "pysubs msub 391 1", #graviton production ffbar, ggbar  G* "pysubs msub 392 1", # acc to Randall-Sundrum model. "pysdat3 mdcy 347 1 1", # Graviton decays "pydat3 mdme 4158 1 0", #all graviton decay modes turned off but… … "pydat3 mdme 4166 1 1", # … the decay G*e+e- … "pydat3 mdme 4177 1 0" ]

Event Generation (2): 

Event Generation (2) For G*Z0Z0 e+e-m+m- or e+e- e+e- or m+m-m+m- Pythia.PythiaCommand += [ "pysubs msel 0", #sub processes must be explicitly switched on "pysubs msub 391 1", #graviton production ggbar, ffbar  G* "pysubs msub 392 1", #acc to Randall-Sundrum model. "pydat3 mdme 4158 1 0", # all graviton decay modes turned off but… … "pydat3 mdme 4176 1 1", # … the decay G* Z0Z0 "pydat3 mdme 4177 1 0" ]

Event Generation (3): 

Event Generation (3) And then enable the Z0e+e- and Z0 m+m Pythia.PythiaCommand += [ "pydat3 mdcy 23 1 1", # Z0 decays "pydat3 mdme 174 1 0", #all Z0 decay modes turned off but .. "pydat3 mdme 182 1 1", # .. Z0  ee "pydat3 mdme 184 1 1", # and Z0  mm … "pydat3 mdme 189 1 0"]

G4 Simulation: 

G4 Simulation Get the files (from SimulationOptionsRome) RomeSimulationConfig.py (edit for input & output data file, events, DetDescrVersion) RomeGeo2G4.py RomeEnvelopes.mac, RomeEnvelopes.xml, RomeEtaPhiFilter.mac, RomeGeometry.mac, PDGTABLE.MeV Additional lines added in job options for DB access: RDBAccessSvc = Service( "RDBAccessSvc" ) RDBAccessSvc.HostName = "pdb01“

Digitization, ESD : 

Digitization, ESD Get files DigitizationConfig.py (edit for input & output data files, events, DetDescrVersion) AtlasDigitization.py ESD production All misconfigurations in event generation, G4 simulation or digitization will result to a fatal crash here. In addition, problems have been observed with Release during last week. Many obscure explanations circulating in atlas-sw-dev list.

AOD and Analysis: 

AOD and Analysis To look the produced events we modified the very similar examples in the AnalysisExamples of Zll (for Gee) and H4l (for G  ZZ  4l). Working to further customize the code to extract more detailed track information. One of our objectives is to use the convienient Physics Analysis Tools.

Required Resources : 

Required Resources About 25 MB required for input data cards & job files.

A Bumpy Road…(1): 

A Bumpy Road…(1) Successfully ran interactively at BNL; the number of events is limited. Running in LSF batch is full of problems: DB servers too busy => timeouts There are continuous patches, modifications in the … released software. Reaching CPU limitations even in the 1 week(?) queue at CERN for 100 evts!

A Bumpy Road…(2): 

A Bumpy Road…(2) And last but not least: Corrupted(?) pool files produced when Nevt>24 ! “Error Severe problem while closing Database. Caught in infinite loop! - ABORT CLOSE.” (see POOL/POOL_1_3_1/src/StorageSvc/src/DbDatabaseObj.cpp) In BNL getting occasional errors “NFS stale file handle” Futile to move to a large scale production now. Need to wait until coming to a ‘stable’ Release !

Initial Data Sample: 

Initial Data Sample One year of running (assume L= 1033 cm-2 s-1) yields ~ 100 events (s~ 10-14 from pythia) Full simulation chain with Rome (initial) conditions 100 evts of G*e+e- 120 evts of G*Z0Z0 e+e- e+e- Standard cuts were used: |h|<2.5 , Ptelec> 20 GeV, etc.

Reconstructed MassGee: 

Reconstructed Mass Gee

Reconstructed MassGZZ  4e: 

Reconstructed Mass GZZ  4e

Reconstructed Mass of Z0: 

Reconstructed Mass of Z0

Some Track quantities: 

Some Track quantities

Summary: 

Summary Successfully fully simulated in ATLAS graviton decay events. Fill ESDs, AODs start doing analysis using Physics Analysis Tools. Start planning for Rome Physics workshop…

Columbia-Nevis Group : 

Columbia-Nevis Group Dominik Dannheim dannheim@nevis.columbia.edu Kamal Benslama benslama@nevis.columbia.edu John Parsons parsons@nevis.columbia.edu http://www.nevis.columbia.edu/~dannheim/tucson/nevis_graviton_tucson_dec_2004.ppt

RS graviton in full simulation: 

RS graviton in full simulation Invariant mass distribution Angular distribution in e+e- CMS gg  G*  e+e-, mG*=500 GeV, generated with PYTHIA including QED-FSR 860 events processed in full simulation, DC 2 layout, software release 9.0.2 Default reconstruction options, no further cuts Analysis on AODs Mass resolution ~3x worse than in ATLFAST Further studies needed to understand the cause of this Columbia - Nevis

Slide23: 

500 GeV G*  e+e- in ATLANTIS event display

Plans for Rome: 

Plans for Rome Fully simulate more graviton decay events to study the kinematics and acceptances. Explore discovery potential for lower graviton masses. Modify standard cuts and apply additional cuts if necessary.

Rome Plans (2): 

Rome Plans (2) Include background High mass SUSY, other exotics Understand calibrations, resolutions Explore the effect of pileup and how it will affect the background. Explore Graviton decays to other SM particles (specifically muons) Expect to proceed to full simulation production in January using GRID.

END: 

END

Gravitons in warped extra dimensions: 

Gravitons in warped extra dimensions Predictions for . . . Dark energy Higgless mass generation Dark matter Hierarchy problem . . .

Graviton Decay Width: 

Graviton Decay Width Total decay width for each KK mode G~3*10-5*N*(k/M)3(mn/L)8(Dm) Lifetime, t of each KK mode: G-1~104*(M/k)3(L8/Dm9) Dm is the mass gap between KK modes. Chang and Yamaguchi, hep-ph/9909523(1999) Randall and Sundrum, Phy. Rev. Let. 83, 3370 (1999)

Dark Energy Signatures in ATLAS: 

Dark Energy Signatures in ATLAS Looking for displaced vertex in TRT (R>56 cm) When rc has some intermediate value Dm may get finite value KK mode lifetime may be ~ fraction of second When Dm ~ 10-3 eV get displaced vertex ~ 1 meter correct scale to describe recently discovered dark energy

Angular Distribution: 

Angular Distribution Spin-2 particles