1. SUSY “Blind Analysis” Plans & Settings
OUTLINE
Reminder of the Project
Tools to be Utilized
Details for the Analyzers
Conclusion and Prospects
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

2. 1. Reminder of the Project
Proposal
Both MC signal and pseudo-data samples to be produced
Pseudo-data=(smeared sum of SM backgrounds) + (all Higgs and SUSY contributions from chosen point in the chosen SUSY X scenario)
High statistics samples of SM background to be produced
Samples are made available to analyzers
Analyzers have to “blindly” determine both the chosen model AND the corresponding parameters (“double challenge”)
Generation and fast simulation tools are made available to analyzers
They can produce additional samples (i.e.: signal templates, larger background statistics,…)
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

3. 1. Reminder of the Project
Goals
Are:
Disentangle different SUSY X scenarios with parameters sets leading to similar topologies
Study the problem posed by the SUSY background to a given SUSY single process (bias on observables measurements due to signal contamination, impact for SUSY parameters fitters)
Solve the « double challenge »
Are not:
To have any reliable detector/trigger simulation
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

4. 3. Tools to be Utilized Event Generation Tools
Pythia v LHAPDF v4.0 + Tauola v(Apr03)
The package is ready and tested
LHC Fast Simulators
ATLFAST v2.20 interfaced to all of the above
Ready and tested
Simplifying Hypotheses
Models: only RPC SUSY
Production processes: restricted to those available in Pythia v6.3
Request to ATLAS Collaborators
If publicly available:
Updated “L3” trigger menus
Updated object ID e vs rejection functions
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

5. 3. Tools to be Utilized Status / Settings PDFs: mt=175 GeV
Preference for LO fits w/ LO aS evolution since Pythia has LO ME, LO aS evolution (for ME and PS)
Would go for Alekhin 2002 LO since there’s a set of 15 PDFs to represent the experimental uncertainties. Also the equivalent sets for NLO and NNLO are available in case one needs to use other generators
mt=175 GeV
No solutions for min.bias events overlay
First tests show that the PAW Ntuples (that include simulated tracks) can only have ~5k entries => will need to set a script doing individual “h2root” plus root-tuples merging
SUSY Signals:
will use SLHA
Pseudo-data:
MC truth infos will be removed
either a single merged root-tuple or blind merges will be provided
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

6. 3. Details for the Analyzers
Normalization:
The process code and statistics will be stored in the root-tuples
The corresponding s will be stored in a ascii file
Trigger:
Some basic “L3” flags are already in the root-tuples
Other menus could be built using the fast reconstructed objects
Analyses will have use only those trigger streams
Statistics:
SM Background sample: at least 100k/sub-process => O(6M events)
Each pseudo-data sample: O(600k events BKGD + 50k SUSY)
Start w/ 2 pseudo-data points
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

7. 3. Details for the Analyzers
CCIN2P3
Production tar file:
Will be provided at cchpssd0:/hpss/in2p3.fr/home/m/muanza/GDR_SUSY/SUSY_Blind/ATLFAST
Background root-tuples & ascii files:
Will be put at cchpssd0:/hpss/in2p3.fr/home/m/muanza/GDR_SUSY/SUSY_Blind/BKGD (w/ 1 sub-directory per process)
Pseudo-data root-tuples & ascii files:
Will be put at
cchpssd0:/hpss/in2p3.fr/home/m/muanza/GDR_SUSY/SUSY_Blind/Pseudo_Data (w/ 1 sub-directory per point)
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005

8. 4. Prospects Things are getting ready
Full speed production could start within a ~2 weeks
A generic ROOT analysis program will be provided
S. Muanza
GDR-SUSY/Colliders LAL October 12th 2005