# Posters

2016-06-15
15:54
Behind every great detector, there are lots of great people!
 Reference: Poster-2016-539 Keywords:  ATLAS  Detector  Collaboration  Collage  Portraits  Experiment  Education  Outreach  Poster Original source: AtlasPosterA1.pdf Created: 2008. -1 p Creator(s): Gagnon, Pauline; Goldfarb, Steven Photo collage of the ATLAS detector, using portraits of ATLAS collaboration members. Related links:Outreach Poster © CERN Geneva Access to file

2016-06-10
15:18
CERN Document Server
CERN Document Server

 Reference: Poster-2016-538 Created: 2016. -1 p Creator(s): Marian, Ludmila; Gabancho, Esteban; Witowski, Sebastian; Tzovanakis, Harris; Costa, Flavio [...] CERN Document Server, cds labs poster for OR2016 conference.CERN Document Server, cds labs poster for OR2016 conference. © CERN Geneva Access to files

2016-06-08
10:27
Measurement of the branching fraction ratio ${\cal B}(B_{c}^{+} \to \psi(2S)\pi^+)/{\cal B}(B_{c}^{+} \to J/\psi\pi^+)$
 Reference: Poster-2016-537 Created: 2016. -1 p Creator(s): An, Liupan Using the $pp$ collision data collected by LHCb at center-of-mass energies $\sqrt{s} \, = 7 \, {\rm TeV} \,$ and $8 \, {\rm TeV} \,$, corresponding to an integrated luminosity of $3 \, \mathrm{fb}^{-1} \,$, the ratio of the branching fraction of the $B_{c}^{+} \to \psi(2S)\pi^+$ decay relative to that of the $B_{c}^{+} \to J/\psi\pi^+$ decay is measured to be ${0.268 \pm 0.032\mathrm{\,(stat)} \pm 0.007\mathrm{\,(syst)} \pm 0.006\,(\mathrm{BF}) }$. The first uncertainty is statistical, the second is systematic, and the third is due to the uncertainties on the branching fractions of the $J/\psi \to \mu^{+}\mu^{-}$ and $\psi(2S) \to \mu^{+}\mu^{-}$ decays. To enhance the signal significance with limited $B_{c}^{+}$ statistics, the boosted decision tree selection is used to separate the signal and background effectively. The systematic uncertainties are discussed extensively. This measurement is consistent with the previous LHCb result, and the statistical uncertainty is halved. Related links:Beauty 2016 © CERN Geneva Access to files

2016-05-20
12:21
Measurement of the difference of time-integrated $CP$ asymmetries in $D^0 \to K^+K^-$ and $D^0 \to \pi^+\pi^-$ decays
 Reference: Poster-2016-536 Keywords:  LHCb Created: 2016. -1 p Creator(s): Marino, Pietro We present precision measurement of difference time-integrated $CP$ asymmetries, $\Delta A_{CP}$, in singly Cabibbo-suppressed modes $D^0 \to K^+K^-$ and $D^0 \to \pi^+\pi^-$, based on the full Run I LHCb data sample, corresponding to an integrated luminosity of $3\mathrm{fb}^{-1}$. Related links:The 16th International Conference on B-Physics at Frontier Machines © CERN Geneva Access to files

2016-05-09
16:01
 Reference: Poster-2016-535 Keywords:  HiRadMat facility  CERN  SPS  Targetry  440 GeV  protons Created: 2016. -1 p Creator(s): Charitonidis, Nikolaos; Fabich, Adrian HiRadMat is a facility constructed in 2011, designed to provide high-intensity pulsed beams to an irradiation area where different material samples or accelerator components can be tested. The facility, located at the CERN SPS accelerator complex, uses a 440 GeV proton beam with a pulse length up to 7.2 μs and a maximum intensity up to 1E13 protons / pulse. The facility, a unique place for performing state-of-the art beam-to-material experiments, operates under transnational access and welcomes and financially supports, under certain conditions, experimental teams to perform their experiments. © CERN Geneva Access to files

2016-04-29
10:55
Geant4 hadronic and electromagnetic validation tests in LHCb
 Reference: Poster-2016-534 Keywords:  LHCb Created: 2016. -1 p Creator(s): Griffith, Peter Noel LHCb uses Geant4 to simulate the interactions of particles with the detector material and components. The simulation response can vary significantly due to modification of material description, of detector geometry, or of the Geant4 toolkit itself. Therefore, an extensive variety of tools have been developed to study the effects of Geant4 modification on the LHCb simulation framework and on stand-alone environments within the LHCb software infrastructure. These tools have proven to be very effective for investigating new and alternative models provided by Geant4, and also in identifying and fixing anomalous behaviours that arise from changes. The next goal is to have these validation tests run autonomously and periodically, alerting the relevant users when problems are detected. Quick and easy comparison of the results from different software versions and simulation models will be made possible through the web interface of the LHCb Performance and Regression testing system, LHCbPR. Related links:LHC Students poster session © CERN Geneva Access to files

2016-04-29
10:51
Novel Real-time Calibration and Alignment Procedure for LHCb Run II
 Reference: Poster-2016-533 Keywords:  LHCb Created: 2016. -1 p Creator(s): Prouve, Claire In order to achieve optimal detector performance the LHCb experiment has introduced a novel real-time detector alignment and calibration strategy for Run II of the LHC. For the alignment tasks, data is collected and processed at the beginning of each fill while the calibrations are performed for each run. This real time alignment and calibration allows the same constants being used in both the online and offline reconstruction, thus improving the correlation between triggered and offline selected events. Additionally the newly computed alignment and calibration constants can be instantly used in the trigger, making it more efficient. The online alignment and calibration of the RICH detectors also enable the use of hadronic particle identification in the trigger. The computing time constraints are met through the use of a new dedicated framework using the multi-core farm infrastructure for the LHCb trigger. An overview of all alignment and calibration tasks is presented and their performance is shown. Related links:LHC Students poster session © CERN Geneva Access to files

2016-04-29
10:41
Bs semileptonic asymmetry at LHCb
 Reference: Poster-2016-532 Keywords:  LHCb Created: 2016. -1 p Creator(s): Dufour, Laurent When neutral $B^{0}_{s,d}$ mesons evolve in time they can change into their own antiparticles. In this mixing process CP symmetry is not necessarily conserved, as the probability for a $B^{0}$ meson to change into a $\bar{B}^{0}$ meson can be different from the probability for the reverse process. The CP violation in the $B^{0}_{s}$ system as measured using semileptonic decays, defined as $a^{s}_{sl}$, is very small according to the Standard Model. However, earlier measurements of the semileptonic mixing asymmetry in both the $B_s^{0}$ and $B_d^{0}$ systems have shown a $3 \sigma$ deviation with respect to the Standard Model value. A measurement of $a^{s}_{sl}$ performed using $1 \text{fb}^{-1}$ of data collected at the LHCb detector is presented, together with an outlook to the updated $3 \text{fb}^{-1}$ result. Related links:LHC Students poster session © CERN Geneva Access to file

2016-03-29
10:51
$B0 \to Ds^{(*)}Ds^{(*)}$ and outlook of $B0 \to D^{(*)}D$ at LHCb
 Reference: Poster-2016-531 Keywords:  LHCb Created: 2016. -1 p Creator(s): Belloli, Nicoletta The measurement of the inclusive branching fraction of $B0s \to Ds^{(*)+} Ds^{(*)-}$ decay together with its contribution to the determination of $\Delta \Gamma{s}/ \Gamma {s}$ are presented. The branching fraction value is compatible with results from previous experiments, improving the world average. The $B0 \to D^+D^-$ and $B0 \to D^*D^{(*)}$ decays are used to measure the parameters associated with $CP$ Violation in those channels; while the analysis associated to the second channel is at an initial stage the first one is almost concluded, the values obtained for the sensitivity on the $CP$ observables show that LHCb can rival the results obtained by previous experiments. Related links:Conference - LHC students poster session © CERN Geneva Access to file

2016-03-29
10:13
Prospects for |V$_{ub}$| measurements at LHCb
 Reference: Poster-2016-530 Keywords:  LHCb Created: 2016. -1 p Creator(s): Stefkova, Slavomira Precise measurements of the quark coupling strength, $|V_{ub}|$, the least well known CKM element, allow a strong test of the unitarity of the CKM matrix. Previous measurements using exclusive and inclusive methods have resulted in values of $|V_{ub}|$ which are 3$\sigma$ apart. The first measurement of $|V_{ub}|$ at LHCb confirmed this tension using the $\Lambda^{0}_{b} \rightarrow p \mu^{-} \overline{\nu}$ decay. This strengthens the motivation to measure this quantity using different channels, one of them being purely leptonic decay $B^{+} \rightarrow \mu^{+} \mu^{-} \mu^{+} \nu$, which benefits from LHCb's very good muon identification ability. This mode had never been observed before. With recent lattice QCD calculations, LHCb can also constrain $|V_{ub}|$ using the $B^{0}_s \rightarrow K^{+} \mu^{-} \overline{\nu}$ decay where the theoretical uncertainty is significantly smaller. Related links:Conference - LHC students poster session Access to files