= !MadAnalysis 5 LLP (Long Lived Particle) =

== LLP with official Delphes 3.4.1 ==

* ~~Test with commented example~~

* Extensive test with signal regions

* Reference event

* ~~one sample with unknown particle~~


== LLP with special Delphes package for MA5 ==

Delphes-LLP package is a special improvement of the Delphes package. Associated to !MadAnalysis 5 v1.6, it allows the user to perform phenomenological investigations with long-lived particles or to recast existed analysis devoted to this kind of signature.

Current status: the package handles neutral LLPs which decay into leptons in the first layers of the CMS tracker (such as neutralino in the framework of RPV-SUSY).

Package[update 2017/08/25]: [http://madanalysis.irmp.ucl.ac.be/raw-attachment/wiki/Korea00-AnalysisList/ma5track_v1.6.tgz ma5track_v1.6.tgz]


=== Changes in the Delphes dataformat: ===

for leptons:
* D0: impact parameter in tranverse plane wrt the closest approach point
* Z: Z-coordinate of the closest approach point


=== New modules in Delphes: ===

* MA5EfficiencyD0: applying efficiency to tracks according to the D0 parameter

  Efficiency functions is coming from 8-TeV tracking performance of CMS, describing in the following wiki: https://twiki.cern.ch/twiki/bin/view/CMSPublic/DisplacedSusyParametrisationStudyForUser
{{{
set EfficiencyFormula { (d0<=20) * (-5.06107e-7 * d0**6 + 0.0000272756 * d0**5 - 0.00049321 * d0**4 + 0.00287189 * d0**3 + 0.00522007 * d0**2 -0.0917957 * d0 +  0.924921) +
                        (d0>20) * (0.00) }
}}}
 
 

== Recast experimental analyses == 

* CMS EXO-16-022: ongoing
  * Center of mass energy: 13 TeV
  * Integrated luminosity: 2.6  fb^-1
  * A search for new long-lived particles decaying to electrons and muons is presented using data from proton-proton collisions produced in 2015 by the LHC. Events are selected with an electron and muon 
    that both have transverse impact parameter values between 200 μm and 10 cm. Since no significant excess is observed, limits are set on the Displaced Supersymmetry model, with pair production of top 
    squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model. 
  * Link to the collaboration page: http://cms-results.web.cern.ch/cms-results/public-results/preliminary-results/EXO-16-022/
  * Link to CDS: https://cds.cern.ch/record/2205146?ln=fr
  * Link to Inspire: http://inspirehep.net/record/1479633/


== Ongoing development ==