Using proton-proton collision data, collected by the LHCb experiment and corresponding to the integrated luminosity of 9 fb
−1
,
the several new
decays to charmonium and three light charged hadrons ...are observed. In particular, following channels are observed
→ ψ(2S)π
+
π
−
π
+
,
→ (ψ(2S) → J/ψπ
+
π
−
)π
+
,
→ J/ψK
+
π
−
π
+
, and
→ J/ψK
+
K
−
K
+
. The first evidence of the
→ ψ(2S)K
+
K
−
π
+
decays is obtained. The branching fractions of these decays are measured with respect to the high-statistic normalization channels.
At present, parallelization technology is a dynamically evolving area in software development. Using parallelization to adapt software to existing multicore and multiprocessor systems, one can ...considerably increase the computational performance and significantly reduce the processing speed for big data arrays. High speed of software operation is important both for real-time data preprocessing and data analysis at all subsequent stages, including data visualization. This is the key requirement for the Large Hadron Collider (LHC) experiments. In this article, the results of using parallelization technology for analyzing LHCb physics data, with the jobs implemented in OSTAP based on pathos and pyROOT, are given.
The first observation of the
→ χ
c
1
(3872)pK
–
decay and the results of precision measurements of χ
c
1
(3872) state parameters in the B
+
→ χ
c
1
(3872)K
+
decays are presented. Relative branching ...fractions of
→ χ
c
1
(3872)pK
–
and
→ ψ(2S)pK
–
decays, as well as B
+
→ χ
c
1
(3872)K
+
and B
+
→ ψ(2S)K
+
are measured. The χ
c
1
(3872) state mass is determined with high accuracy, and the natural particle width is measured for first time. The study is performed using the data collected by the LHCb detector in proton–proton collisions at center-of-mass energies of 7, 8, and 13 TeV.
The results of search for new decays of beauty baryons in the LHCb experiment are presented. In particular the new decays Λ
b
0
→ψ(2
S
)
pπ
−
,
Λ
b
0
→
Λ
c
+
p
p
¯
π
−
, Λ
b
0
→
pK
−
π
+
π
−
, Λ
b
0
...→
pK
−
K
+
K
−
, Ξ
b
0
→
pK
−
π
+
π
−
, Ξ
b
0
→
pK
−
π
+
K
−
are observed and ratios of branching fractions are measured. The results are based on the proton-proton collisions data collected by the LHCb experiment at the Large Hadron Collider.
During the process of designing new devices for the high-speed metallization process, there appears the necessity to define the stable operation range and search for the optimum values of the ...operation mode and design parameters. This paper describes a process of optimization of a device made for depositing low-melting metal coatings, based on the rocket chamber operation principle. The paper presents an analysis of the objective function surface response metallizer operation performance. On the basis of this analysis the optimal values of fuel mass flow rate and excess oxidant ratio were determined. The choice of fuel and oxidizer throttling orifice cross-section areas was substantiated, the value of the throat cross-section for the metallizer flow-path was found. The expected performance of the designed device was also determined.
The production of P-wave quarkonium states, χ
b
, was studied in the LHCb experiment at the Large Hadron Collider (LHC, CERN) in proton–proton collisions at the c.m. energies of 7 and 8 TeV. The ...results obtained on the basis of a measurement of the relative cross sections for χ
b
-meson production, the first ever observation of the decay process χ
b
(3
P
) → ϒ(3
S
)
γ
, and a precise measurement of the mass of the χ
b
1
(3
P
) state are presented in this article.
The paper presents a device for spraying the low-melting metal coating, based on the rocket chamber operation principle. The design of the fuel nozzle, pre-mixing chamber, and radial combustion ...chamber is considered. The processes of electro-spark ignition of the fuel mixture and the flame front stabilization are described. The choice of the critical section area as a place of the coating material feeding in the high-temperature combustion products flow is substantiated.
The Hadron Calorimeter of LHCb (HCAL) is one of the four sub-detectors of the experiment calorimetric system, which also includes: Scintillator Pad Detector (SPD), Pre-Shower Detector (PS), and ...electromagnetic (ECAL) calorimeter. The main purpose of HCAL is to provide data for Level-0 trigger for selection events with high transverse energy hadrons. It is important to have a precise and reliable calibration system which produces result immediately after the calibration run. LHCb HCAL is equipped with a calibration system based on 137Cs radioactive source embedded into the calorimeter structure. It allows to obtain absolute calibration with good precision and monitor technical condition of the detector.
The first ever observation of the decay process
B
0
→
J
/ψη′ is described. The branching ratios were measured for the decay processes
B
(s)
→ J/ψη(′), and the η–η′ mixing angles were determined on ...this basis. The first indication of the occurrence of the decay process
B
s
→ ψ(2
S
)η′ is presented. The respective analysis was performed on the basis of data accumulated with the LHCb detector in proton–proton collisions at the c.m. collision energies of 7 and 8 TeV and the integrated luminosity of 3 fb
−1
.
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