D. G. Hitlin
A5001073596- 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
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Computational Physics and Python Applications
- Black Holes and Theoretical Physics
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Muon and positron interactions and applications
- Nuclear physics research studies
- Nuclear Physics and Applications
- Particle accelerators and beam dynamics
- Cosmology and Gravitation Theories
- Advanced Data Storage Technologies
- Atomic and Molecular Physics
- Stochastic processes and statistical mechanics
- Radiation Therapy and Dosimetry
- Astrophysics and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- International Science and Diplomacy
California Institute of Technology
2015-2024
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2019-2021
Fermi National Accelerator Laboratory
2021
Joint Institute for Nuclear Research
2021
Istituto Nazionale di Fisica Nucleare, Sezione di Lecce
2021
Yale University
2021
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2021
Istituto Nazionale di Fisica Nucleare, Sezione di Trieste
2021
Stanford University
1978-2018
SLAC National Accelerator Laboratory
1985-2018
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...
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 study the reaction e+e−→e+e−π0 in single tag mode and measure differential cross section dσ/dQ2 γγ∗→π0 transition form factor momentum transfer range from 4 to 40 GeV2. At Q2>10 GeV2 measured exceeds asymptotic limit predicted by perturbative QCD. The analysis is based on 442 fb−1 of integrated luminosity collected at PEP-II with BABAR detector e+e− center-of-mass energies near 10.6 GeV.16 MoreReceived 29 May 2009DOI:https://doi.org/10.1103/PhysRevD.80.052002©2009 American Physical Society
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...
A precise measurement of the cross section process e+ e- to pi+ pi- (gamma) from threshold an energy 3 GeV is obtained with initial state radiation (ISR) method using 232 fb^-1 data collected BABAR detector at center-of-mass energies near 10.6 GeV. The ISR luminosity determined a study leptonic mu+ mu- gamma (gamma). leading-order hadronic contribution muon magnetic anomaly calculated pi measured 1.8 (514.1 +-2.2(stat} +-3.1(syst}) x 10^{-10}.
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...
We report a revised determination of charmed-D-meson absolute branching fractions based on complete reconstruction DD¯ events at the ψ(3770). Two backgrounds, Cabibbo-suppressed and multi-π0 D decays, are addressed in detail. The first measurement decay D0→K−π+π0π0 establishes sensitivity to hitherto unobserved modes. Removal both backgrounds reduces values our previously reported by (21-24)%, leaving their ratios largely unchanged. new unable account fully for deficit charm production...
A precise measurement of the cross section process $e^+e^-\toπ^+π^-(γ)$ from threshold to an energy 3GeV is obtained with initial-state radiation (ISR) method using 232fb$^{-1}$ data collected BaBar detector at $e^+e^-$ center-of-mass energies near 10.6GeV. The ISR luminosity determined a study leptonic $e^+e^-\toμ^+μ^-(γ)γ_{\rm ISR}$, which found agree next-to-leading-order QED prediction within 1.1%. for systematic uncertainty 0.5% in dominant $ρ$ resonance region. leading-order hadronic...
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...
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.
The present report documents the results of Working Group 2: B, D and K decays, workshop on Flavor in Era LHC, held at CERN from November 2005 through March 2007. With advent we will be able to probe New Physics (NP) up energy scales almost one order magnitude larger than it has been possible with accelerator facilities. While direct detection new particles main avenue establish presence NP indirect searches provide precious complementary information, since most probably not measure full...
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...
We present a study of the decay properties charmed D mesons produced near peak ψ''(3770) resonance in e+e− annihilation. Branching fractions for nine Cabibbo-favored and three Cabibbo-suppressed modes are presented along with upper limits on one additional four modes. A Kππ-decay-mode Dalitz plots reveals large quasi-two-body pseudoscalar-vector component D0 decays an apparent nonuniform population plot D+ into K−π+π+. Using tagged events, we measure charged-particle multiplicity...
A new technique is applied to data collected at the $\ensuremath{\psi}(3770)$ resonance derive charmed-$D$-meson branching fractions without relying on measurement of $D$-production cross sections. Measurements are presented for three decay modes ${D}^{0} ({K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}, {D}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{+}, \mathrm{and} {K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0}$ and four...
We report the results of a search for bottomonium ground state eta_b(1S) in photon energy spectrum with sample (109 +/- 1) million Upsilon(3S) recorded at BABAR detector PEP-II B factory SLAC. observe peak E_gamma = 921.2 {+2.1} {-2.8} (stat) 2.4(syst) MeV significance 10 standard deviations. interpret observed as being due to monochromatic photons from radiative transition -> gamma eta_b(1S). This corresponds an mass $9388.9 {+3.1} {-2.3} 2.7(syst) MeV/c2. The hyperfine...
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 report the results of a search for $Z(4430)^-$ decay to $J/\psi\pi^-$ or $\psi(2S)\pi^-$ in $B^{-,0}\to \jpsi\pi^- K^{0,+}$ and \psitwos \pi^- decays. The data were collected with BABAR detector at SLAC PEP-II asymmetric-energy $e^+e^-$ collider operating center mass energy 10.58 \gev, sample corresponds an integrated luminosity 413 fb$^{-1}$. Each $K\pi$ distribution exhibits clear $K^{\ast}(892)$ $K^{\ast}_2(1430)$ signals, efficiency-corrected spectrum is well-described by...