1,752 research outputs found
Properties and Decays of the meson
Recent studies of properties and decays of the meson by the LHC
experiments are presented. Mass and lifetime measurements are discussed and
some of the many new observed decays are reported.Comment: Presented at the 2014 Flavor Physics and CP Violation (FPCP-2014),
Marseille, France, May 26-30 2014, 10 pages, 6 figure
Fast Data-Driven Simulation of Cherenkov Detectors Using Generative Adversarial Networks
The increasing luminosities of future Large Hadron Collider runs and next
generation of collider experiments will require an unprecedented amount of
simulated events to be produced. Such large scale productions are extremely
demanding in terms of computing resources. Thus new approaches to event
generation and simulation of detector responses are needed. In LHCb, the
accurate simulation of Cherenkov detectors takes a sizeable fraction of CPU
time. An alternative approach is described here, when one generates high-level
reconstructed observables using a generative neural network to bypass low level
details. This network is trained to reproduce the particle species likelihood
function values based on the track kinematic parameters and detector occupancy.
The fast simulation is trained using real data samples collected by LHCb during
run 2. We demonstrate that this approach provides high-fidelity results.Comment: Proceedings for 19th International Workshop on Advanced Computing and
Analysis Techniques in Physics Research. (Fixed typos and added one missing
reference in the revised version.
Towards Reliable Neural Generative Modeling of Detectors
The increasing luminosities of future data taking at Large Hadron Collider
and next generation collider experiments require an unprecedented amount of
simulated events to be produced. Such large scale productions demand a
significant amount of valuable computing resources. This brings a demand to use
new approaches to event generation and simulation of detector responses. In
this paper, we discuss the application of generative adversarial networks
(GANs) to the simulation of the LHCb experiment events. We emphasize main
pitfalls in the application of GANs and study the systematic effects in detail.
The presented results are based on the Geant4 simulation of the LHCb Cherenkov
detector.Comment: 6 pages, 4 figure
Muon identification for LHCb Run 3
Muon identification is of paramount importance for the physics programme of
LHCb. In the upgrade phase, starting from Run 3 of the LHC, the trigger of the
experiment will be solely based on software. The luminosity increase to
cms will require an improvement of the muon
identification criteria, aiming at performances equal or better than those of
Run 2, but in a much more challenging environment. In this paper, two new muon
identification algorithms developed in view of the LHCb upgrade are presented,
and their performance in terms of signal efficiency versus background reduction
is shown
Fabrication and Characterisation of 3D Diamond Pixel Detectors With Timing Capabilities
Diamond sensors provide a promising radiation hard solution to the challenges posed by the future experiments at hadron machines. A 3D geometry with thin columnar resistive electrodes orthogonal to the diamond surface, obtained by laser nanofabrication, is expected to provide significantly better time resolution with respect to the extensively studied planar diamond sensors. We report on the development, production, and characterisation of innovative 3D diamond sensors achieving 30% improvement in both space and time resolution with respect to sensors from the previous generation. This is the first complete characterisation of the time resolution of 3D diamond sensors and combines results from tests with laser, beta rays and high energy particle beams. Plans and strategies for further improvement in the fabrication technology and readout systems are also discussed
Measurement of the mass and lifetime of the baryon
A proton-proton collision data sample, corresponding to an integrated
luminosity of 3 fb collected by LHCb at and 8 TeV, is used
to reconstruct , decays. Using the , decay mode for calibration, the lifetime ratio and absolute
lifetime of the baryon are measured to be \begin{align*}
\frac{\tau_{\Omega_b^-}}{\tau_{\Xi_b^-}} &= 1.11\pm0.16\pm0.03, \\
\tau_{\Omega_b^-} &= 1.78\pm0.26\pm0.05\pm0.06~{\rm ps}, \end{align*} where the
uncertainties are statistical, systematic and from the calibration mode (for
only). A measurement is also made of the mass difference,
, and the corresponding mass, which
yields \begin{align*} m_{\Omega_b^-}-m_{\Xi_b^-} &= 247.4\pm3.2\pm0.5~{\rm
MeV}/c^2, \\ m_{\Omega_b^-} &= 6045.1\pm3.2\pm 0.5\pm0.6~{\rm MeV}/c^2.
\end{align*} These results are consistent with previous measurements.Comment: 11 pages, 5 figures, All figures and tables, along with any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-008.htm
- …