A5062604318- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Medical Imaging Techniques and Applications
- Computational Physics and Python Applications
- Black Holes and Theoretical Physics
- Nuclear physics research studies
- Radiation Detection and Scintillator Technologies
- Cosmology and Gravitation Theories
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Atomic and Molecular Physics
- CCD and CMOS Imaging Sensors
- Lanthanide and Transition Metal Complexes
- advanced mathematical theories
- Muon and positron interactions and applications
- Cardiac Imaging and Diagnostics
- Bayesian Methods and Mixture Models
- Amino Acid Enzymes and Metabolism
- Astrophysics and Cosmic Phenomena
Ruhr University Bochum
2013-2022
Laboratoire d’Annecy de Physique des Particules
2002-2018
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
2018
University of the Basque Country
2018
Institut National de Physique Nucléaire et de Physique des Particules
2018
Centre National de la Recherche Scientifique
2018
Universitat de Barcelona
2018
Lawrence Berkeley National Laboratory
2012
University of California, Berkeley
2012
Brunel University of London
2009
Based on the full BABAR data sample, we report improved measurements of ratios R(D(*))=B(B[over ¯]→D(*)τ(-)ν[over ¯](τ))/B(B[over ¯]→D(*)ℓ(ℓ)(-)ν[over ¯](ℓ)), where ℓ is either e or μ. These are sensitive to new physics contributions in form a charged Higgs boson. We measure R(D)=0.440±0.058±0.042 and R(D(*))=0.332±0.024±0.018, which exceed standard model expectations by 2.0σ 2.7σ, respectively. Taken together, our results disagree with these at 3.4σ level. This excess cannot be explained...
We study initial-state radiation events, ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\gamma}}_{\mathrm{ISR}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}J/\ensuremath{\psi}$, with data collected the BABAR detector. observe an accumulation of events near $4.26\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ in invariant-mass spectrum ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}J/\ensuremath{\psi}$. Fits to mass indicate that a broad resonance about is...
Searches for lepton-flavor-violating decays of a tau lepton to lighter mass and photon have been performed with the entire data set (963+/-7)x10{6} collected by BABAR detector near Upsilon(4S), Upsilon(3S) Upsilon(2S) resonances. The searches yield no evidence signals we upper limits on branching fractions B(tau{+/-}-->e{+/-}gamma)<3.3x10{-8} B(tau{+/-}-->mu{+/-}gamma)<4.4x10{-8} at 90% confidence level.
Dark sectors charged under a new Abelian interaction have recently received much attention in the context of dark matter models. These models introduce light mediator, so-called photon (A′), connecting sector to standard model. We present search for reaction e+e−→γA′, A′→e+e−, μ+μ− using 514 fb−1 data collected with BABAR detector. observe no statistically significant deviations from model predictions, and we set 90% confidence level upper limits on mixing strength between at 10−4−10−3...
We search for single-photon events in 53 fb−1 of e+e− collision data collected with the BABAR detector at PEP-II B-Factory. look a single high-energy photon and large missing momentum energy, consistent production spin-1 particle A′ through process e+e−→γA′; A′→invisible. Such particles, referred to as "dark photons," are motivated by theories applying U(1) gauge symmetry dark matter. find no evidence such processes set 90% confidence level upper limits on coupling strength mass range mA′≤8...
We present a measurement of the cross section process e(+)e(-)-->pi(+)pi(-)psi(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at SLAC PEP-II e(+)e(-) storage rings. The study is based on 298 fb(-1) data recorded with BABAR detector. A structure observed in not far above threshold, near 4.32 GeV. also investigate compatibility this Y(4260) previously reported by experiment.
The e+e−→pp¯ cross section is determined over a range of pp¯ masses, from threshold to 4.5 GeV/c2, by studying the e+e−→pp¯γ process. data set corresponds an integrated luminosity 232 fb−1, collected with BABAR detector at PEP-II storage ring, e+e− center-of-mass energy 10.6 GeV. mass dependence ratio electric and magnetic form factors, |GE/GM|, measured for masses below 3 GeV/c2; its value found be significantly larger than 1 up 2.2 GeV/c2. We also measure J/ψ→pp¯ ψ(2S)→pp¯ branching...
We present a study of the decays B^{0,+} --> J/psi pi^+ pi^- pi^0 K^{0,+}, using 467 10^6 BBbar pairs recorded with BABAR detector. evidence for decay mode X(3872) omega, product branching fractions B(B^+ X(3872)K^+) B(X(3872) omega) =[0.6\pm0.2\stat \pm 0.1\syst ] 10^{-5}, and B(B^0 X(3872)K^0) =[0.6\pm0.3\stat 10^{-5}. A detailed mass distribution from favors negative-parity assignment.
In a search for $B\ensuremath{\rightarrow}c\overline{c}\ensuremath{\gamma}K$ decays with the BABAR detector, where $c\overline{c}$ includes $J/\ensuremath{\psi}$ and $\ensuremath{\psi}(2S)$, $K$ ${K}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}_{S}^{0}$, ${K}^{*}(892)$, we find evidence $X(3872)\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\gamma}$ $X(3872)\ensuremath{\rightarrow}\ensuremath{\psi}(2S)\ensuremath{\gamma}$ $3.6\ensuremath{\sigma}$ $3.5\ensuremath{\sigma}$ significance,...
We search for evidence of a light scalar boson in the radiative decays Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such particle appears extensions standard model, where CP-odd Higgs naturally couples strongly to b quarks. find no such processes mass range 0.212 < or = mA0 9.3 GeV samples 99 x 10(6) 122 collected by BABAR detector at SLAC PEP-II B factory set stringent upper limits on effective coupling quark A0. also limit dimuon branching fraction etab...
The BaBar detector operated successfully at the PEP-II asymmetric e+e− collider SLAC National Accelerator Laboratory from 1999 to 2008. This report covers upgrades, operation, and performance of systems, as well trigger, online offline computing, aspects event reconstruction since beginning data taking.
We present a study of the decays B0,+→J/ψωK0,+ using 383×106 B¯¯¯B events obtained with BABAR detector at PEP-II. observe Y(3940)→J/ψω, mass 3914.6+3.8−3.4(stat)±2.0(syst) MeV/c2, and width 34+12−8(stat)±5(syst) MeV. The ratio B0 B+ decay to YK is 0.27+0.28−0.23(stat)+0.04−0.01(syst), relevant branching fractions are reported.Received 14 November 2007DOI:https://doi.org/10.1103/PhysRevLett.101.082001©2008 American Physical Society
The process e+e- --> p anti-p gamma is studied using 469 fb-1 of integrated luminosity collected with the BABAR detector at PEP-II collider, an center-of-mass energy 10.6 GeV. From analysis invariant mass spectrum, dependence cross section for measured from threshold to 4.5 ratio electric and magnetic form factors, |G_E/G_M|, asymmetry in proton angular distribution are masses below 3 We also measure branching fractions decays J/psi psi(2S) anti p.
We present a study of resonances in exclusive decays $B$ mesons to ${\overline{D}}^{(*)}{D}^{(*)}K$. report the observation $B\ensuremath{\rightarrow}{\overline{D}}^{(*)}{D}_{s1}^{+}(2536)$ where ${D}_{s1}^{+}(2536)$ is reconstructed ${D}^{*0}{K}^{+}$ and ${D}^{*+}{K}_{S}^{0}$ decay channels. also $B\ensuremath{\rightarrow}\ensuremath{\psi}(3770)K$ $\ensuremath{\psi}(3770)$ ${\overline{D}}^{0}{D}^{0}$ ${D}^{\ensuremath{-}}{D}^{+}$. In addition, we an enhancement for...
We study the reactions e+e−→e+e−η(') in single-tag mode and measure γγ∗→η(') transition form factors momentum-transfer range from 4 to 40 GeV2. The analysis is based on 469 fb−1 of integrated luminosity collected at PEP-II with BABAR detector e+e− center-of-mass energies near 10.6 GeV.11 MoreReceived 5 January 2011DOI:https://doi.org/10.1103/PhysRevD.84.052001© 2011 American Physical Society
We study the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\psi}(2S){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ with initial-state-radiation events produced at PEP-II asymmetric-energy collider. The data were recorded BABAR detector center-of-mass energies and near $\mathrm{\ensuremath{\Upsilon}}(\mathrm{nS})$ ($n=2,3,4$) resonances correspond to an integrated luminosity of $520\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$. investigate...
We present a measurement of the direct CP violating asymmetry in decay B0-->K+pi(-) using data sample 227x10(6) Upsilon(4S)-->BB decays collected with BABAR detector at PEP-II asymmetric-energy e(+)e(-) collider SLAC. observe total signal yield nK-(pi(+))+nK+(pi(-))=1606+/-51 and measure (nK-(pi(+))-nK+(pi(-)))/(nK-(pi(+))+nK+(pi(-)))=-0.133+/-0.030(stat)+/-0.009(syst). The probability observing such an absence violation is 1.3x10(-5), corresponding to 4.2 standard deviations.
We study the processes e+ e- --> 3(pi+pi-)gamma, 2(pi+pi-pi0)gamma and K+ K- 2(pi+pi-)gamma, with photon radiated from initial state. About 20,000, 33,000 4,000 fully reconstructed events, respectively, have been selected 232 fb-1 of BaBar data. The invariant mass hadronic final state defines effective e+e- center-of-mass energy, so that these data can be compared corresponding direct measurements. From 3(pi+pi-), 2(pi+pi-pi0) 2(pi+pi-) spectra, cross sections for are measured energies...
We study the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathit{\ensuremath{\Lambda}}\overline{\mathit{\ensuremath{\Lambda}}}\ensuremath{\gamma}$, $\mathit{\ensuremath{\Lambda}}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}\ensuremath{\gamma}$, ${\mathit{\ensuremath{\Sigma}}}^{0}{\overline{\mathit{\ensuremath{\Sigma}}}}^{0}\ensuremath{\gamma}$ processes using $230\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity collected by BABAR detector at...
In a study of ${B}^{+}\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\gamma}{K}^{+}$ decays, we find evidence for the radiative decay $X(3872)\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\gamma}$ with statistical significance $3.4\ensuremath{\sigma}$. We measure product branching fractions...
We present evidence for D0-D(0) mixing in D(0)-->K(+)pi(-) decays from 384 fb(-1) of e(+)e(-) colliding-beam data recorded near square root s=10.6 GeV with the BABAR detector at PEP-II storage rings Stanford Linear Accelerator Center. find parameters x('2)=[-0.22+/-0.30(stat)+/-0.21(syst)] x 10(-3) and y(')=[9.7+/-4.4(stat)+/-3.1(syst)] a correlation between them -0.95. This result is inconsistent no-mixing hypothesis significance 3.9 standard deviations. measure R(D), ratio doubly...
A search for the nonconservation of lepton flavor in decay ${\ensuremath{\tau}}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{e}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\gamma}$ has been performed with $2.07\ifmmode\times\else\texttimes\fi{}{10}^{8}$ ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}{\ensuremath{\tau}}^{\ensuremath{-}}$ events collected by BABAR detector at SLAC PEP II storage ring a center-of-mass energy near 10.58 GeV. We find no...
We present measurements of the decays B+ -> X(3872) K+ and B0 K0 with Jpsi pi+ pi-. The data sample used, collected BABAR detector at PEP-II e+e- asymmetric-energy storage ring, corresponds to 455 x 10^6 BBbar pairs. Branching fraction BF(B+ K+) BF(X(3872) pi-) = (8.4 +/- 1.5 0.7) 10^{-6} BF(B0 K0) pi- (3.5 1.9 0.4) are obtained. set an upper limit on natural width Gamma < 3.3 MeV/c^2 90% confidence level.
A search for charmonium and other new states is performed in a study of exclusive initial-state-radiation production $D\overline{D}$ events from electron-positron annihilations at center-of-mass energy 10.58 GeV. The data sample corresponds to an integrated luminosity $384\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ was recorded by the BABAR experiment PEP-II storage ring. mass spectrum shows clear evidence $\ensuremath{\psi}(3770)$ plus structures near 3.9, 4.1, $4.4\text{...