A5025568178- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Neutrino Physics Research
- Medical Imaging Techniques and Applications
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- Black Holes and Theoretical Physics
- Distributed and Parallel Computing Systems
- Radiation Detection and Scintillator Technologies
- Nuclear physics research studies
- advanced mathematical theories
- Astrophysics and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Advanced Data Storage Technologies
- Stochastic processes and statistical mechanics
- International Science and Diplomacy
- Big Data Technologies and Applications
- Advanced NMR Techniques and Applications
- X-ray Spectroscopy and Fluorescence Analysis
University of Iowa
2016-2025
Istanbul University
2023-2024
A. Alikhanyan National Laboratory
2024
SR Research (Canada)
2024
Federación Española de Enfermedades Raras
2024
Atlas Scientific (United States)
2024
The University of Adelaide
2019-2023
Northern Illinois University
2023
Boğaziçi University
2023
Siddaganga Institute of Technology
2021
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...
A fully compensating uranium—scintillator calorimeter was constructed for the ZEUS detector at HERA. Several of barrel modules were subjected to beam tests Fermilab before shipping them DESY installation. The calibrations used beams electrons and hadrons, measuring uniformity response, checking resolution. runs also provided opportunity test a large fraction actual readout system in an integrated environment more than one year HERA turn on. experiment utilized two computer controlled...
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 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...
Evidence is presented for a narrow state, called \ensuremath{\xi}, in the decay modes J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\xi}, \ensuremath{\xi}\ensuremath{\rightarrow}${K}^{+}$${K}^{\mathrm{\ensuremath{-}}}$, and \ensuremath{\xi}\ensuremath{\rightarrow}${K}_{S}^{0}$${K}_{S}^{0}$. In ${K}^{+}$${K}^{\mathrm{\ensuremath{-}}}$ mode, \ensuremath{\xi} has mass of 2.230\ifmmode\pm\else\textpm\fi{}0.006\ifmmode\pm\else\textpm\fi{}0.014 GeV/${c}^{2}$, width...
We have carried out an amplitude analysis of the ${K}_{S}^{0}{K}_{S}^{0}$ system produced in reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}{K}_{S}^{0}{K}_{S}^{0}n$ at 23 GeV/c, based on about 15 000 events low-$t$ region ($|t\ensuremath{-}{t}_{min}|<0.1$ Ge${\mathrm{V}}^{2}$). Below 1.6 GeV/${\mathit{c}}^{2}$, our favored solution is very similar to those from previous analyses. For higher masses, we observe decay $h(2040)$ meson. In addition, $l=0$ partial wave...
Measurements of the exclusive branching fractions B(D0→π−e+νe) and B(D0→K−e+νe), using data collected at ψ(3770) with Mark III detector SLAC e+e− storage ring SPEAR, are used to determine ratio Kobayashi-Maskawa matrix elements ‖Vcd/Vcs∥2 =0.057±+0.0380.015±0.005.Received 30 December 1988DOI:https://doi.org/10.1103/PhysRevLett.62.1821©1989 American Physical Society
We search for the rare flavor-changing neutral current process $B^{+}\rightarrow K^{+}τ^{+}τ^{-}$ using data from BABAR experiment. The sample, collected at center-of-mass energy of $Υ{(4S)}$ resonance, corresponds to a total integrated luminosity 424 fb$^{-1}$ and 471 million $B\overline{B}$ pairs. reconstruct one $B$ meson, produced in $Υ{(4S)}\rightarrow B^{+} B^{-}$ decay, many hadronic decay modes activity compatible with K^{+} τ^{+}τ^{-}$ rest event. Each $τ$ lepton is required...
We study the lepton forward-backward asymmetry ${\mathcal{A}}_{FB}$ and longitudinal ${K}^{*}$ polarization ${F}_{L}$, as well an observable ${P}_{2}$ derived from them, in rare decays $B\ensuremath{\rightarrow}{K}^{*}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, where ${\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ is either ${e}^{+}{e}^{\ensuremath{-}}$ or ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$, using full sample of 471 million...
This paper presents the charged-particle multiplicity distributions for ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$ annihilation at \ensuremath{\surd}s =29 GeV measured in High Resolution Spectrometer. The data, which correspond to an integrated luminosity of 185 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$, were obtained SLAC storage ring PEP. techniques used correct observed prong numbers are discussed. distribution charged particles has a mean value...
Results from a partial-wave analysis of the decay J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\gamma}${\mathit{K}}_{\mathit{S}}^{0}$${\mathit{K}}^{\ifmmode\pm\else\textpm\fi{}}$${\mathrm{\ensuremath{\pi}}}^{\ensuremath{\mp}}$ in ${\mathit{K}}_{\mathit{S}}^{0}$${\mathit{K}}^{\ifmmode\pm\else\textpm\fi{}}$${\mathrm{\ensuremath{\pi}}}^{\ensuremath{\mp}}$ invariant-mass range 1.35--1.6 GeV/${\mathit{c}}^{2}$ are presented. Within isobar model, data this mass best described by mixture...
We present measurements of the two-body decays J/\ensuremath{\psi} into a vector and pseudoscalar meson. The data, taken with Mark III detector at SLAC ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$ storage ring SPEAR, consist 5.8\ifmmode\times\else\texttimes\fi{}${10}^{6}$ produced J/\ensuremath{\psi}'s. branching ratios for \ensuremath{\rho}\ensuremath{\pi}, \ensuremath{\rho}\ensuremath{\eta}, \ensuremath{\rho}\ensuremath{\eta}', \ensuremath{\omega}${\ensuremath{\pi}}^{0}$,...
An angular analysis of the decay ${\overline{B} \rightarrow D^\ast \ell^- \overline{\nu}_\ell}$, $\ell\in\{e,\mu\}$, is reported using full $e^+e^-$ collision data set collected by \babar experiment at $\Upsilon(4S)$ resonance. One $B$ meson from ${\Upsilon(4S)\to B\overline{B}}$ fully reconstructed in a hadronic mode, which constrains kinematics and provides determination neutrino momentum vector. The semileptonic described di-lepton mass squared, $q^2$, three angles. first unbinned fit to...
We present a search for neutral, long-lived particle L that is produced in e+ e- collisions and decays at significant distance from the interaction point into various flavor combinations of two oppositely charged tracks. The analysis uses an data sample with luminosity 489.1 fb(-1) collected by BABAR detector ϒ(4S), ϒ(3S), ϒ(2S) resonances just below ϒ(4S). Fitting two-track mass distribution signal peak, we do not observe signal, set 90% confidence level upper limits on product production...
We study the process $e^+e^- \to \pi^+\pi^-\eta \gamma$, where photon is radiated from initial state. About 8000 fully reconstructed events of this are selected BaBar data sample with an integrated luminosity 469~fb$^{-1}$. Using $\pi^+\pi^-\eta$ invariant mass spectrum we measure \pi^+\pi^-\eta$ cross section in $e^+e^-$ center-of-mass energy range 1.15 to 3.5 GeV. The well described by Vector-Meson Dominance model four $\rho$-like states. observe $49\pm9$ $J/\psi$ decay $\pi^+\pi^-\eta$,...
We study the processes $\gamma \gamma \to \eta_c \eta' K^+ K^-$, $\eta' \pi^+ \pi^-$, and $\eta \pi^-$ using a data sample of 519 $fb^{-1}$ recorded with BaBar detector operating at SLAC PEP-II asymmetric-energy $e^+e^-$ collider center-of-mass energies near $\Upsilon(nS)$ ($n = 2,3,4$) resonances. This is first observation decay $\eta_c K^-$ we measure branching fraction $\Gamma(\eta_c K^-)/(\Gamma(\eta_c \pi^-)=0.644\pm 0.039_{\rm stat}\pm 0.032_{\rm sys}$. Significant interference...
Measurements of the branching ratios ten Cabibbo-suppressed hadronic weak decays ${D}^{+}$ and ${D}^{0}$ are presented from data collected with Mark III detector SPEAR. In addition to previously observed channels ${D}^{0}$\ensuremath{\rightarrow}${K}^{\mathrm{\ensuremath{-}}}$${K}^{+}$ ${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\pi}}^{+}$, we report new measurements...
Absolute branching fractions for the ${\mathit{D}}_{\mathit{l}3}$ and ${\mathit{D}}_{\mathit{l}4}$ decays ${\mathit{D}}^{+}$\ensuremath{\rightarrow}K\ifmmode\bar\else\textasciimacron\fi{} $^{0}$${\mathit{e}}^{+}$${\ensuremath{\nu}}_{\mathit{e}}$,${\mathit{D}}^{+}$\ensuremath{\rightarrow}K\ifmmode\bar\else\textasciimacron\fi{} $^{0}\mathrm{\ensuremath{\mu}}^{+}$${\ensuremath{\nu}}_{\mathrm{\ensuremath{\mu}}}$, $^{\mathrm{*}0}$${\mathit{e}}^{+}$${\ensuremath{\nu}}_{\mathit{e}}$,...
Data from the High Resolution Spectrometer at SLAC storage ring PEP have been used to study inclusive production of baryons and mesons. Time-of-flight measurements are identify charged hadrons. Neutral hadrons identified effective-mass peaks associated with their decay into two particles. Cross sections other characteristics presented for ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}^{\ifmmode\pm\else\textpm\fi{}}$, ${K}^{0}$ (K${\ifmmode\bar\else\textasciimacron\fi{}}^{0}$)...
We report a measurement of the reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}\ensuremath{\phi}\ensuremath{\phi}n$ at 22.6 GeV/c. The $\ensuremath{\phi}\ensuremath{\phi}$ effectivemass spectrum shows concentration events from threshold to about 2.4 GeV/${\mathit{c}}^{2}$. From data near 2.8 GeV/${\mathit{c}}^{2}$ effective mass, we place an upper limit on $\ensuremath{\sigma}$ times branching ratio 2 nb (90% confidence level) for production ${\ensuremath{\eta}}_{c}$...