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Inclusive detached dilepton mva rate reduction

Reducing the minbias rate/bandwidth of the Inclusive detached dilepton MVA trigger lines. Especially tightening the dielectron selection

Minbias rate calculated using hlt1 filtered 2024 minbias simulation. lhcb/wg/rta/WP3/bandwidth_division/Beam6800GeV-expected-2024-MagDown-nu7.6/hlt1_filtered/30000000/input_x.dst

Trigger line Inclusive rate / kHz Exclusive rate / kHz
e^+ e^- \ (OS) 0.96000 +/- 0.3392 kHz 0.48000 +/- 0.2399 kHz
e^+ e^- \pi^+ \ (OS) 0.96000 +/- 0.3392 kHz 0.12000 +/- 0.1199 kHz
e^+ e^- \pi^+ \ (SS) 0.72 +/- 0.2938 kHz 0.0 +/- 0.0 kHz
e^+ e^- \pi^+ \pi^- \ (OS) 1.08 +/- 0.3598 kHz 0.12000 +/- 0.1199 kHz
e^+ e^- \pi^+ \pi^- \ (SS) 0.96000 +/- 0.3392 kHz 0.12000 +/- 0.1199 kHz
e^+ e^- \ (SS) 0.36 +/- 0.2078 kHz 0.24000 +/- 0.1696 kHz
e^+ e^- N \ (OS) 1.55999 +/- 0.4323 kHz 0.48000 +/- 0.2399 kHz
e^+ e^- N \ (SS) 1.32 +/- 0.3977 kHz 0.36 +/- 0.2078 kHz
e^+ \mu^- \ (OS) 0.24000 +/- 0.1696 kHz 0.12000 +/- 0.1199 kHz
e^+ \mu^- \pi^+ \ (OS) 0.24000 +/- 0.1696 kHz 0.0 +/- 0.0 kHz
e^+ \mu^- \pi+ \ (SS) 0.24000 +/- 0.1696 kHz 0.0 +/- 0.0 kHz
e^+ \mu^- \pi+ \pi^- \ (OS) 0.24000 +/- 0.1696 kHz 0.12000 +/- 0.1199 kHz
e^+ \mu^- \pi+ \pi^- \ (SS) 0.12000 +/- 0.1199 kHz 0.0 +/- 0.0 kHz
e^+ \mu^- \ (SS) 0.24000 +/- 0.1696 kHz 0.12000 +/- 0.1199 kHz
e^+ \mu^- N \ (OS) 0.24000 +/- 0.1696 kHz 0.12000 +/- 0.1199 kHz
e^+ \mu^- N \ (SS) 0.12000 +/- 0.1199 kHz 0.0 +/- 0.0 kHz
\mu^+ \mu^- \ (OS) 1.08 +/- 0.3598 kHz 0.72 +/- 0.2938 kHz
\mu^+ \mu^- \pi^+ \ (OS) 0.36 +/- 0.2078 kHz 0.12000 +/- 0.1199 kHz
\mu^+ \mu^- \pi^+ \ (SS) 0.24000 +/- 0.1696 kHz 0.0 +/- 0.0 kHz
\mu^+ \mu^- \pi^+\pi^- \ (OS) 0.12000 +/- 0.1199 kHz 0.0 +/- 0.0 kHz
\mu^+ \mu^- \pi^+ \pi^- \ (SS) 0.12000 +/- 0.1199 kHz 0.0 +/- 0.0 kHz
\mu^+ \mu^- \ (SS) 0.48000 +/- 0.2399 kHz 0.24000 +/- 0.1696 kHz
\mu^+ \mu^- N \ (OS) 0.24000 +/- 0.1696 kHz 0.0 +/- 0.0 kHz
\mu^+ \mu^- N \ (SS) 0.24000 +/- 0.1696 kHz 0.12000 +/- 0.1199 kHz
Total 7 +/-0.9 kHz

This is a reduction from the current rate of 11 +- 1 kHz

Assuming an events size of 200 kB this corresponds to a bandwidth of 1.33 GB/s

HLT2 Selection efficiencies (CanRecoChildren) for a selection of important decays after tightening the selection

Decay Dimuon eff Dielectron eff MuE eff
B^{0} -> ( K^{*0}(892) -> K+ \pi- ) \mu+ \mu- 0.463 +/- 0.031
B^{0} -> ( K^{*0}(892) -> K+ \pi- ) e+ e- 0.278 +/- 0.033
B^{0} -> ( K^{*0}(892) -> K+ \pi- ) \mu+ e- 0.441 +/- 0.051
B+ -> K+ \mu+ \mu- 0.543 +/- 0.024
B+ -> K+ e+ e- 0.396 +/- 0.030
B+ -> K+ e+ \mu- 0.409 +/- 0.037
Bs0 -> \mu+ \mu- 0.627 +/- 0.022
Bs0 -> e- \mu+ 0.550 +/- 0.033
Bs0 -> e+ e- 0.507 +/- 0.025

HLT2 Selection efficiencies (CanRecoChildren) for some important decays with the current selection in the master branch

Decay Dimuon eff Dielectron eff MuE eff
B^{0} -> ( K^{\star 0}(892) -> K+ \pi- ) \mu+ \mu- 0.471 \pm 0.031
B^{0} -> ( K^{\star 0}(892) -> K+ \pi- ) e+ e- 0.299 \pm 0.033
B^{0} -> ( K^{\star 0}(892) -> K+ \pi- ) \mu+ e- 0.452 \pm 0.052
B+ -> K+ \mu+ \mu- 0.552 \pm 0.023
B+ -> K+ e+ e- 0.427 \pm 0.031
B+ -> K+ e+ \mu- 0.432 \pm 0.037
Bs0 -> \mu+ \mu- 0.627 \pm 0.022
Bs0 -> e- \mu+ 0.571 \pm 0.033
Bs0 -> e+ e- 0.535 \pm 0.025

Tightening the selection leads to the loss of about 1-3 % points in signal efficiency depending on the mode

Edited by Leon David Carus

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