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Add Hlt2RD_LbToPpKmPipPimMuMu_MVA line

Add Hlt2RD_LbToPpKmPipPimMuMu_MVA line. Used for searching for rare decay \Lambda_{b}\to p K^-\pi^+\pi^-\mu^+\mu^-, optimized using MVA method

Bandwidth and rate

Tested with scripts in rd-rta-guide/testing-utils

Only this line:

file size bandwidth rate
No MVA 0.22 MB 2.98 MB/s 108.44 Hz
With MVA 0.0 MB 0.0 MB/s. 0.0 Hz

All RD turbo lines:

file size bandwidth
rd-devel-june25 30 MB 406.6413 MB/s
This MR 30 MB 406.6413 MB/s

Got same total bandwidth. The rate comparison is here: compare_rate.log

Selection

Much looser cut compare to Hlt2RD_LbToPpKmPipPimMuMu, especially pions cuts

Background suppressed by a BDT

All cuts are summarized in following tables:

Particles Variable Value
All final states isLong true
Particles Variable Value
Muon isMuon true
p_{\mathrm{T}} >250\mathrm{MeV}/c
p >3000\mathrm{MeV}/c
\chi^2_{\mathrm{IP}} >4
\mathrm{PID}_{\mu} >2
Particles Variable Value
DiMuon Mass [200, 5400]\mathrm{MeV}/c^2
p_{\mathrm{T}} >0\mathrm{MeV}/c
\chi^2_{\mathrm{DOCA}} <20
\chi^2_{\mathrm{vtx}}/\mathrm{ndof} <10
\chi^2_{\mathrm{FD}} >20
Particles Variable Value
Pion hasRich true
p_{\mathrm{T}} >0\mathrm{MeV}/c
\chi^2_{\mathrm{IP}} >4
\mathrm{PID}_{K} <-1
Particles Variable Value
DiPion Mass [0, 4000]\mathrm{MeV}/c^2
p_{\mathrm{T}} >0\mathrm{MeV}/c
\chi^2_{\mathrm{DOCA}} <20
\chi^2_{\mathrm{vtx}}/\mathrm{ndof} <9
Particles Variable Value
Proton hasRich true
p_{\mathrm{T}} >300\mathrm{MeV}/c
p >9\mathrm{GeV}/c
\chi^2_{\mathrm{IP}} >4
\mathrm{PID}_{p} >0
\mathrm{PID}_{p}-\mathrm{PID}_{K} >-2
Particles Variable Value
Kaon hasRich true
p_{\mathrm{T}} >250\mathrm{MeV}/c
p >3.0\mathrm{GeV}/c
\chi^2_{\mathrm{IP}} >4
\mathrm{PID}_{K} >0
Particles Variable Value
pK^-\pi^+\pi^- Mass [0, 5.5]\mathrm{GeV}/c^2
\Sigma p_{\mathrm{T}} >1.5\mathrm{GeV}/c
\Sigma \chi^{2}_{\mathrm{IP}} >20.0
\mathrm{max}(\chi^{2}_{\mathrm{DOCA}}) < 20
\chi^2_{\mathrm{vtx}}/\mathrm{ndof} < 16
Particles Variable Value
\Lambda_b Mass [4800, 6900]\mathrm{MeV}/c^2
p_{\mathrm{T}} >2500\mathrm{MeV}/c
\chi^2_{\mathrm{vtx}} <25
\mathrm{DIRA} >0.995
\chi^2_{\mathrm{IP}} <25
\chi^2_{\mathrm{FD}} >40
\chi^2_{\mathrm{DOCA}} >25

BDT

BDT trained with:

  • Bkg proxy: Hlt2RD_LbToPpKmPipPimMuMu sideband <5100 MeV, >6100 MeV
  • Sig proxy: 2016,2017,2018 MC

Train variables:

  • p_{\mathrm{T}} of all final states except pions
  • Logarithm of \chi^2_{\mathrm{IP}} of all final states and \Lambda_b
  • Sum of p_{\mathrm{T}} of hadronic final states
  • Logarithm of sum of \chi^2_{\mathrm{IP}} of all hadronic final states

Working point: -0.1

Weight file: lhcb-datapkg/ParamFiles!154 (merged)

BDT response:

overtrain_BDT

Edited by Qi Shi

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