D. Bernard
A5004617011- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Radiation Detection and Scintillator Technologies
- Cosmology and Gravitation Theories
- Nuclear physics research studies
- Black Holes and Theoretical Physics
- Radiation Therapy and Dosimetry
- Atomic and Molecular Physics
- Superconducting Materials and Applications
- Radio Astronomy Observations and Technology
- Advanced Data Storage Technologies
- Nuclear Physics and Applications
- Pulsars and Gravitational Waves Research
- Laser-induced spectroscopy and plasma
- Advanced X-ray Imaging Techniques
Centre National de la Recherche Scientifique
2014-2024
École Polytechnique
2014-2024
Laboratoire Leprince-Ringuet
2015-2024
Laboratoire d'Informatique de l'École Polytechnique
1990-2020
American Society for Radiation Oncology
2018
Campbell Collaboration
2009-2014
Johns Hopkins University
2014
University of Pisa
2014
Laboratoire de Physique Nucléaire et de Hautes Énergies
1999-2002
Stanford University
2001
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...
Based on the full BaBar data sample, we report improved measurements of ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B l Nu), where is either e or mu. 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 2.0 sigma 2.7 sigma, respectively. Taken together, our results disagree with these at 3.4 level. This excess cannot be explained boson type II two-Higgs-doublet...
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...
Many models of physics beyond the Standard Model predict existence new Abelian forces with gauge bosons mediating interactions between "dark sectors" and Model. We report a search for dark boson Z' coupling only to second third generations leptons in reaction e+e- -> mu+mu- Z', using 514 fb-1 data collected by BABAR experiment. No significant signal is observed masses range 0.212 - 10 GeV. Limits on parameter g' as low 7x10^-4 are derived, leading improvements bounds compared those...
In a sample of $471\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ events collected with the BABAR detector at PEP-II ${e}^{+}{e}^{\ensuremath{-}}$ collider we study rare decays $B\ensuremath{\rightarrow}{K}^{(*)}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, where ${\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ is either or ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$. We report results on partial branching fractions and isospin...
We search for the flavor-changing neutral-current decays $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, and invisible $J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ $\ensuremath{\psi}(2S)\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ via $B\ensuremath{\rightarrow}{K}^{(*)}J/\ensuremath{\psi}$ $B\ensuremath{\rightarrow}{K}^{(*)}\ensuremath{\psi}(2S)$, respectively, using a data sample of...
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.
Although CP violation in the B meson system has been well established by factories, there no direct observation of time-reversal violation. The decays entangled neutral mesons into definite flavor states (B(0) or B(0)), and J/ψK(L)(0) ccK(S)(0) final (referred to as B(+) B(-)), allow comparisons between probabilities four pairs T-conjugated transitions, for example, B(0) → B(-) B(0), a function time difference two decays. Using 468 × 10(6) BB produced Υ(4S) collected BABAR detector at SLAC,...
We present a search for the decay ${B}^{+}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu}$ using $467.8\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected at $\ensuremath{\Upsilon}(4S)$ resonance with BABAR detector SLAC PEP-II $B$-Factory. select sample of events one completely reconstructed ${B}^{\ensuremath{-}}$ in hadronic mode (${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{(*)0}{X}^{\ensuremath{-}}$ and...
We report the results of a study exclusive charmless semileptonic decays, B^0 --> pi^- l^+ nu, B^+ pi^0 omega eta nu and eta^' (l = e or mu) undertaken with approximately 462x10^6 B\bar{B} pairs collected at Upsilon(4S) resonance BABAR detector. The analysis uses events in which signal B decays are reconstructed loose neutrino reconstruction technique. obtain partial branching fractions several bins q^2, square momentum transferred to lepton-neutrino pair, for nu. From these distributions,...
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 measurements of Collins asymmetries in the inclusive process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}X$, where $\ensuremath{\pi}$ stands for charged pions, at a center-of-mass energy 10.6 GeV. use data sample $468\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected by BABAR experiment PEP-II $B$ factory SLAC, and consider pairs pions produced opposite hemispheres hadronic events. observe clear distributions azimuthal angles two...
The All-sky Medium Energy Gamma-ray Observatory (AMEGO) is a probe class mission concept that will provide essential contributions to multimessenger astrophysics in the late 2020s and beyond. AMEGO combines high sensitivity 200 keV 10 GeV energy range with wide field of view, good spectral resolution, polarization sensitivity. Therefore, key study astrophysical objects have unique signatures gamma-ray regime, such as neutron star mergers, supernovae, flaring active galactic nuclei....
We study the process $e^+e^-\to J/\psi\pi^{+}\pi^{-}$ with initial-state-radiation events produced at PEP-II asymmetric-energy collider. The data were recorded BaBar detector center-of-mass energies 10.58 and 10.54 GeV, correspond to an integrated luminosity of 454 $\mathrm{fb^{-1}}$. investigate $J/\psi \pi^{+}\pi^{-}$ mass distribution in region from 3.5 5.5 $\mathrm{GeV/c^{2}}$. Below 3.7 $\mathrm{GeV/c^{2}}$ $\psi(2S)$ signal dominates, above 4 there is a significant peak due Y(4260). A...
The photon spectrum in the inclusive electromagnetic radiative decays of $B$ meson, $B\ensuremath{\rightarrow}{X}_{s}\ensuremath{\gamma}$ plus $B\ensuremath{\rightarrow}{X}_{d}\ensuremath{\gamma}$, is studied using a data sample $(382.8\ifmmode\pm\else\textpm\fi{}4.2)\ifmmode\times\else\texttimes\fi{}{10}^{6}\mathit{\ensuremath{\Upsilon}}(4S)\ensuremath{\rightarrow}B\overline{B}$ collected by BABAR experiment at SLAC. used to extract branching fraction...
A precise measurement of the cross section for process e+e−→K+K−(γ) from threshold to an energy 5 GeV is obtained with initial-state radiation (ISR) method using 232 fb−1 data collected BABAR detector at e+e− center-of-mass energies near 10.6 GeV. The uses effective ISR luminosity determined e+e−→μ+μ−(γ)γISR same set. corresponding lowest-order contribution hadronic vacuum polarization term in muon magnetic anomaly found be aμKK,LO=(22.93±0.18stat±0.22syst)×10−10. charged kaon form factor...
We study the process $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\omega}$ using a data sample of $519.2\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ recorded by BABAR detector at SLAC PEP-II asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider center-of-mass energies near $\ensuremath{\Upsilon}(nS)$ ($n=2,3,4$) resonances. confirm existence charmoniumlike resonance $X(3915)$ decaying to $J/\ensuremath{\psi}\ensuremath{\omega}$ with...