Search for CP violation in the Bs/Bs-bar system

We present studies from the LHCb experiment leading to the measurement of the weak phase {\phi}s. At first, flavor tagging is established by measuring the B0s oscillation frequency \Deltams. Then, flavor tagging is used to perform a measurement of the well known CKM angle sin 2{\beta} in B0 \rightarrow J/{\psi} KS0, before we constrain {\phi}s through an amplitude analysis of B0s \rightarrow J/{\psi} {\phi} decays. These studies use about 35 inverse pb of data taken in 2010. In addition, we present the measurement of B(B+\rightarrowJ/{\psi}{\pi}+)/B(B+\rightarrowJ/{\psi}K+) and the first observation of B0s \rightarrowJ/{\psi}f2'(1525).Comment: 3 pages, 6 figures, The 19th Particles & Nuclei International Conference (PANIC11), MIT, Boston, July 24th-29th, 201

Using a new multivariate technique in high energy physics

This project focuses on testing and developing algorithms for multivariate data analysis, that separate signal processes from abundant backgrounds and on helping with organizing and filtering colossal amounts of raw data, gathered from the Large Hadron Collider beauty (LHCb) experiment, to find extremely rare events of interest. Moreover, working on this project also meant trying to apply new, faster method to take the place of systems that are now used at CERN to pare down the relevant data, but require relatively extensive processing and analysis to determine relevance and usefulness

Improved constraints on γ\gamma: CKM2014 update

I report on an updated combination of all currently available tree-level measurements of the CKM angle $\gamma$ from LHCb. This combination currently gives LHCb's most precise value of $\gamma = (73^{+9}_{-10})^\circ$ obtained from $B\to DK$-like decays. For the first time in a single experiment, the uncertainty has dropped below $10^\circ$. When using $B\to D\pi$ decays in addition, the situation becomes more difficult to interpret.Comment: on behalf of the LHCb collaboration. Proceedings of the 8th International Workshop on the CKM Unitarity Triangle (CKM 2014), Vienna, Austria, September 8-12, 201

Results on direct CP Violation on B decays in LHCb

I present three studies from the LHCb experiment on the subject of direct CP violation in $B^0$ and $B_s$ decays. First, we measure the CP asymmetry in $B^\pm\to\psi K^\pm$ decays, with $\psi=J/\psi, \psi(2S)$, using 0.35 $fb^{-1}$ of $pp$ collisions at $\sqrt{s}=7 TeV$. We find no evidence for CP violation. Second, using the same data sample, we see the first evidence of CP violation in the decays of $B_s$ mesons to $K^\pm\pi^-\pi^+$ pairs, $A_{CP}(B_s\to K\pi) = 0.27 \pm 0.08 {\rm (stat)}\pm 0.02 {\rm (syst)}$ ($3.3\sigma$). Third, using 1.0 $fb^{-1}$ of data, measurements of CP sensitive observables of the $B^\pm\to D K^\pm$ system are presented. They include the first observation of the suppressed mode $B^\pm\to[\pi^\pm K^\mp]_D K^\pm$. Combining several $D$ final states, CP violation in $B^\pm\to D K^\pm$ decays is observed with a significance of $5.8\sigma$.I present three studies from the LHCb experiment on the subject of direct CP violation in $B^0$ and $B_s$ decays. First, we measure the CP asymmetry in $B^\pm\to\psi K^\pm$ decays, with $\psi=J/\psi, \psi(2S)$, using 0.35 $fb^{-1}$ of $pp$ collisions at $\sqrt{s}=7 TeV$. We find no evidence for CP violation. Second, using the same data sample, we see the first evidence of CP violation in the decays of $B_s$ mesons to $K^\pm\pi^-\pi^+$ pairs, $A_{CP}(B_s\to K\pi) = 0.27 \pm 0.08 {\rm (stat)}\pm 0.02 {\rm (syst)}$ ($3.3\sigma$). Third, using 1.0 $fb^{-1}$ of data, measurements of CP sensitive observables of the $B^\pm\to D K^\pm$ system are presented. They include the first observation of the suppressed mode $B^\pm\to[\pi^\pm K^\mp]_D K^\pm$. Combining several $D$ final states, CP violation in $B^\pm\to D K^\pm$ decays is observed with a significance of $5.8\sigma$

Measurement of \gamma\ from B->Dh decays at LHCb---including the effect of D0-D0bar mixing

I present a measurement of the CKM angle gamma from a combination of three LHCb measurements using the tree decays B -> DK and B -> Dpi. These measurements are based on a dataset corresponding to 1.0fb-1, collected in 2011. In contrast to what was presented at FPCP, these proceedings fully include the effect of D0--D0b mixing on the combination. I also report on the inclusion of new, preliminary results on the Dalitz analysis of B->DK, D->KShh, using a dataset corresponding to 3fb-1, collected in 2011--2012.I present a measurement of the CKM angle gamma from a combination of three LHCb measurements using the tree decays B -> DK and B -> Dpi. These measurements are based on a dataset corresponding to 1.0fb-1, collected in 2011. In contrast to what was presented at FPCP, these proceedings fully include the effect of D0--D0b mixing on the combination. I also report on the inclusion of new, preliminary results on the Dalitz analysis of B->DK, D->KShh, using a dataset corresponding to 3fb-1, collected in 2011--2012