Precise measurements of CP violation provide stringent tests of the Standard
Model towards the search for signs of new physics. Using LHC proton-proton
collision data, collected by the LHCb detector during 2015 and 2016 at the centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 1.9 fb−1
,
presented is the latest measurement of the CP -violating phase, ϕs
, using B
0
s →
J/ψϕ decays. The machine-learning-based data selection, data-driven corrections
to simulated event samples, and the control of systematic effects using dedicated
samples are discussed. The values ϕs = −0.083±0.041±0.006 rad, ∆Γs = 0.077±
0.008±0.003 ps−1
(i.e. the decay width difference between the light and the heavy
mass eigenstates in the B
0
s
system) and Γs −Γd = −0.0041±0.0024±0.0015 ps−1
(i.e. the difference of the average B
0
s
and B
0
d meson decay widths) are obtained,
yielding the World’s most precise determination of these quantities 1
.
Furthermore, shown are the efforts and contributions towards the LHCb Upgrade:
the quality assurance and testing of the LHCb RICH Upgrade components,
and the redesign and upgrade of the fully online software trigger – LHCb HLT
Upgrade. Regarding the former, an original implementation of a parallelised,
robust and highly available automation system is introduced. In connection to
the latter, a novel neural network architecture and optimisation methods are
laid out, enabling complex machine learning to be performed in a low latency
high-throughput environment. Those directly influence the future deployment of
the experiment and its data collecting and analysis capabilities. Thus, they are
essential for future more precise and stringent research
