Budker Institute of Nuclear Physics

About: Budker Institute of Nuclear Physics is a facility organization based out in Novosibirsk, Russia. It is known for research contribution in the topics: Large Hadron Collider & Branching fraction. The organization has 4147 authors who have published 6586 publications receiving 235245 citations. The organization is also known as: Federal State Institution of Science Institute of Nuclear Physics. GI Budker, Siberian Branch of the Russian Academy of Sciences.

Test of lepton universality using b^{+}k^{+}ℓ^{+}ℓ^{-} decays

Abstract: A measurement of the ratio of the branching fractions of the B+→K+μ+μ− and B+→K+e+e− decays is presented using proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb−1, recorded with the LHCb experiment at center-of-mass energies of 7 and 8 TeV. The value of the ratio of branching fractions for the dilepton invariant mass squared range 1

Measurement of the negative muon anomalous magnetic moment to 0.7 ppm

Abstract: We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{μ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both μ^{+} and μ^{-}, the new experimental average of a_{μ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

The BABAR detector

Abstract: BABAR, the detector for the SLAC PEP-II asymmetric e+e- B Factory operating at the upsilon 4S resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagentic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by dE/dx measurements in the tracking detectors and in a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

Search for the lepton flavour violating decay μ + → e + γ with the full dataset of the MEG experiment

Abstract: The final results of the search for the lepton flavour violating decay $$\mathrm {\mu }^+ \rightarrow \mathrm {e}^+ \mathrm {\gamma }$$ based on the full dataset collected by the MEG experiment at the Paul Scherrer Institut in the period 2009–2013 and totalling $$7.5\times 10^{14}$$ stopped muons on target are presented. No significant excess of events is observed in the dataset with respect to the expected background and a new upper limit on the branching ratio of this decay of $$ \mathcal{B} (\mu ^+ \rightarrow \mathrm{e}^+ \gamma ) < 4.2 \times 10^{-13}$$ (90 % confidence level) is established, which represents the most stringent limit on the existence of this decay to date.

Performance of the ALICE experiment at the CERN LHC

Abstract: ALICE is the heavy-ion experiment at the CERN Large Hadron Collider. The experiment continuously took data during the first physics campaign of the machine from fall 2009 until early 2013, using proton and lead-ion beams. In this paper we describe the running environment and the data handling procedures, and discuss the performance of the ALICE detectors and analysis methods for various physics observables.