- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Particle Detector Development and Performance
- Computational Physics and Python Applications
- Black Holes and Theoretical Physics
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Medical Imaging Techniques and Applications
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Nuclear physics research studies
- Astrophysics and Cosmic Phenomena
- Advanced NMR Techniques and Applications
- Distributed and Parallel Computing Systems
- Cosmology and Gravitation Theories
- Algorithms and Data Compression
- advanced mathematical theories
- Atomic and Molecular Physics
- CCD and CMOS Imaging Sensors
- Stochastic processes and statistical mechanics
- Radioactive Decay and Measurement Techniques
- Cold Atom Physics and Bose-Einstein Condensates
Indian Institute of Technology Madras
2016-2025
Centre National de la Recherche Scientifique
1996-2024
Institute of High Energy Physics
2018-2024
Université de Strasbourg
2020-2024
Budker Institute of Nuclear Physics
2024
Siberian Branch of the Russian Academy of Sciences
2024
COMSATS University Islamabad
2024
China University of Geosciences
2024
Institute of Business Administration Karachi
2024
Carnegie Mellon University
2024
The cross section for ee+ e- → π+ π- J/ψ between 3.8 and 5.5 GeV is measured with a 967 fb(-1) data sample collected by the Belle detector at or near Υ(nS) (n = 1,2,…,5) resonances. Y(4260) state observed, its resonance parameters are determined. In addition, an excess of production around 4 observed. This feature can be described Breit-Wigner parametrization properties that consistent Y(4008) was previously reported Belle. study decays, structure observed in M(π(±)J/ψ) mass spectrum 5.2σ...
We report the observation of two narrow structures in mass spectra pi+-Y(nS) (n=1,2,3) and pi+-hb(mP)(m$ (m=1,2) pairs that are produced association with a single charged pion Y(5S) decays. The measured masses widths averaged over five final states M_1=(10607.2+-2.0) MeV/c2, Gamma_1=(18.4+-2.4) MeV M_2=(10652.2+-1.5) Gamma_2=(11.5+-2.2) MeV. results obtained 121.4 1/fb data sample collected Belle detector vicinity resonance at KEKB asymmetric-energy e+e- collider.
We report the first measurement of $\ensuremath{\tau}$ lepton polarization ${P}_{\ensuremath{\tau}}({D}^{*})$ in decay $\overline{B}\ensuremath{\rightarrow}{D}^{*}{\ensuremath{\tau}}^{\ensuremath{-}}{\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ as well a new ratio branching fractions...
We report a measurement of the ratio ${\cal R}(D^*) = {\cal B}(\bar{B}^0 \rightarrow D^{*+} \tau^- \bar{\nu}_{\tau})/{\cal \ell^- \bar{\nu}_{\ell})$, where $\ell$ denotes an electron or muon. The results are based on data sample containing $772\times10^6$ $B\bar{B}$ pairs recorded at $\Upsilon(4S)$ resonance with Belle detector KEKB $e^+ e^-$ collider. select $B^0 \bar{B}^0$ by reconstructing both $B$ mesons in semileptonic decays to $D^{*\mp} \ell^{\pm}$. measure R}(D^*)= 0.302 \pm...
With the full data sample of $772 \times 10^6$ $B{\bar B}$ pairs recorded by Belle detector at KEKB electron-positron collider, decay $\bar{B} \rightarrow D^* \tau^- \bar{\nu}_\tau$ is studied with hadronic $\tau$ decays $\tau^- \pi^- \nu_\tau$ and \rho^- \nu_\tau$. The polarization $P_\tau(D^*)$ in two-body measured, as well ratio branching fractions $R(D^{*}) = \mathcal{B}(\bar {B} \bar{\nu}_\tau) / \mathcal{B}(\bar{B} \ell^- \bar{\nu}_\ell)$, where $\ell^-$ denotes an electron or a muon....
We present a measurement of ${R}_{{K}^{*}}$, the branching fraction ratio $\mathcal{B}(B\ensuremath{\rightarrow}{K}^{*}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})/\mathcal{B}(B\ensuremath{\rightarrow}{K}^{*}{e}^{+}{e}^{\ensuremath{-}})$, for both charged and neutral $B$ mesons. The case ${R}_{{K}^{*+}}$ is first ever performed. In addition, we report absolute fractions individual modes in bins squared dilepton invariant mass ${q}^{2}$. analysis based on data sample $711\text{...
We report a measurement of the process $\ensuremath{\gamma}{\ensuremath{\gamma}}^{*}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}$ with $759\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample recorded Belle detector at KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. The pion transition form factor, $F({Q}^{2})$, is measured for kinematical region $4\text{ }{\mathrm{GeV}}^{2}\ensuremath{\lesssim}{Q}^{2}\ensuremath{\lesssim}40\text{ }{\mathrm{GeV}}^{2}$, where...
We perform a full amplitude analysis of B0→ψ′K+π− decays, with ψ′→μ+μ− or e+e−, to constrain the spin and parity Z(4430)−. The JP=1+ hypothesis is favored over 0−, 1−, 2− 2+ hypotheses at levels 3.4σ, 3.7σ, 4.7σ 5.1σ, respectively. based on 711 fb−1 data sample that contains 772×106 BB¯ pairs collected Υ(4S) resonance by Belle detector asymmetric-energy e+e− collider KEKB.7 MoreReceived 20 June 2013DOI:https://doi.org/10.1103/PhysRevD.88.074026© 2013 American Physical Society
We present results from a study of $X(3872)\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi}J/\ensuremath{\psi}$ decays produced via exclusive $B\ensuremath{\rightarrow}KX(3872)$ decays. determine the mass to be ${M}_{X(3872)}=(3871.85\ifmmode\pm\else\textpm\fi{}0.27(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.19(\mathrm{syst}))\text{ }\text{ }\mathrm{MeV}$, 90% confidence level upper limit on natural width ${\ensuremath{\Gamma}}_{X(3872)}<1.2\text{ product branching fraction...
We present the results of an amplitude analysis anti-B0 -> J/psi K- pi+ decays. A new charged charmoniumlike state Zc(4200)+ decaying to is observed with a significance 6.2 sigma. The mass and width are 4196 +31-29 +17-13 MeV/c^2 370 +70-70 +70-132 MeV, respectively; preferred assignment quantum numbers J^P = 1^+. In addition, we find evidence for Zc(4430)+ pi+. based on 711 fb^-1 data sample collected by Belle detector at asymmetric-energy e+ e- collider KEKB.
We measure the branching fraction of B−→τ−¯ντ using full Υ(4S) data sample containing 772×106 B¯¯¯B pairs collected with Belle detector at KEKB asymmetric-energy e+e− collider. Events are tagged by reconstructing one B mesons decaying into hadronic final states, and candidates detected in recoil. find evidence for a significance 3.0 standard deviations including systematic errors B(B−→τ−¯ντ)=[0.72+0.27−0.25(stat)±0.11(syst)]×10−4.Received 16 November...
We report the first observations of spin-singlet bottomonium states hb(1P) and hb(2P). The are produced in reaction e+e−→hb(nP)π+π− using a 121.4 fb−1 data sample collected at energies near Υ(5S) resonance with Belle detector KEKB asymmetric-energy e+e− collider. determine M[hb(1P)]=(9898.2+1.1+1.0−1.0−1.1) MeV/c2 M[hb(2P)]=(10 259.8±0.6+1.4−1.0) MeV/c2, which correspond to P-wave hyperfine splittings ΔMHF=(+1.7±1.5) (+0.5+1.6−1.2) respectively. significances hb(2P) 5.5σ 11.2σ, find that...
We present a determination of the magnitude Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ using decay $B\to D\ell\nu_\ell$ ($\ell=e,\mu$) based on 711 fb$^{-1}$ $e^+e^-\to \Upsilon(4S)$ data recorded by Belle detector and containing $772 \times 10^6$ $B\bar{B}$ pairs. One $B$ meson in event is fully reconstructed hadronic mode while other, signal side, partially from charged lepton either $D^+$ or $D^0$ total 23 modes. The isospin-averaged branching fraction found to be...
We report measurement of the cross section $e^+e^-\to \pi^+\pi^-\psi(2S)$ between 4.0 and $5.5 {\rm GeV}$, based on an analysis initial state radiation events in a $980 \rm fb^{-1}$ data sample recorded with Belle detector. The properties $Y(4360)$ $Y(4660)$ states are determined. Fitting mass spectrum $\pi^+\pi^-\psi(2S)$ two coherent Breit-Wigner functions, we find solutions identical width but different couplings to electron-positron pairs: $M_{Y(4360)} = (4347\pm 6\pm 3) MeV}/c^2$,...
We report a study of $B\to (J/\psi \gamma) K$ and (\psi' \gamma)K$ decay modes using $772\times 10^{6}$ $B\bar{B}$ events collected at the \Upsilon(4S)$ resonance with Belle detector KEKB energy-asymmetric $e^+ e^-$ collider. observe $X(3872) \to J/\psi \gamma$ first evidence for $\chi_{c2} in (X_{c\bar{c}}\gamma) decays, while search \psi' no significant signal is found. measure branching fractions, $\mathcal{B}(B^{\pm} X(3872) K^{\pm}) \mathcal{B}(X(3872) J/\psi\gamma)$ $=$...
We report on a search for heavy neutrinos in B-meson decays. The results are obtained using data sample that contains 772x10^6 BB-bar pairs collected at the Upsilon(4S) resonance with Belle detector KEKB asymmetric-energy e+e- collider. No signal is observed and upper limits set mixing of left-handed Standard Model mass range 0.5 - 5.0 GeV/c^2.
We report the results of a study exclusive semileptonic decays B->pi0lnu, B->pi+lnu, B->rho0lnu, B->rho+lnu and B->omegalnu, where l represents an electron or muon. The events are tagged by fully reconstructing second B meson in event hadronic decay mode. measured branching fractions Br(B->pi0lnu) = (0.80 +- 0.08 0.04)x10^-4, Br(B->pi+lnu) (1.49 0.09 0.07)x10^-4, Br(B->rho0lnu) (1.83 0.10 0.10)x10^-4, Br(B->rho+lnu) (3.22 0.27 0.24)x10^-4, Br(B->omegalnu) =(1.07 0.16 first error is...
We report the first determination of relative strong-phase difference between D^0 -> K^0_S,L K^+ K^- and D^0-bar K^-. In addition, we present updated measurements pi^+ pi^- pi^-. Both exploit quantum coherence a pair mesons produced from psi(3770) decays. The differences measured are important for determining Cabibbo-Kobayashi-Maskawa angle gamma/phi_3 in B^- D^0-tilde decays, where is or meson decaying to K^0_S h^+ h^- (h=pi,K), manner independent model assumed describe decay. Using our...
Using the entire CLEO-c \psi(3770)-> D\bar{D} event sample, corresponding to an integrated luminosity of $818 pb^-1 and approximately 5.4 million events, we present a study decays D^0 -> \pi^- e^+ \nu_e, K^- D^+ \pi^0 \bar{K}^0 \nu_e. Via tagged analysis technique, in which one D is fully reconstructed hadronic mode, partial rates for semileptonic by other are measured several q^2 bins. We fit these using form factor parameterizations report results, including shape parameters branching...
Using the CLEO-c detector at Cornell Electron Storage Ring, we have measured inclusive and exclusive cross sections for production of D+, D0 Ds+ mesons in e+e- annihilations thirteen center-of-mass energies between 3.97 4.26 GeV. Exclusive are presented final states consisting two charm (DD, D*D, D*D*, Ds+Ds-, Ds*+Ds-, Ds*+Ds*-) processes which charm-meson pair is accompanied by a pion. No enhancement any state observed energy Y(4260).
We measure the branching ratio of purely leptonic decay D+ meson with unprecedented precision as B(D+ -> mu+ nu) = (3.82 +/- 0.32 0.09)x10^(-4), using 818/pb data taken on psi(3770) resonance CLEO-c detector at CESR collider. use this determination to derive a value for pseudoscalar constant fD+, combining measurements lifetime and assuming |Vcd| |Vus|. find fD+ (205.8 8.5 2.5) MeV. The rate asymmetry [B(D+ nu)-B(D- mu- nu)]/[B(D+ nu)+B(D- nu)] 0.08 0.08, consistent no CP violation. also set...
We present the first model-independent measurement of absolute branching fraction Λ(c)(+) → pK(-)π(+) decay using a data sample 978 fb(-1) collected with Belle detector at KEKB asymmetric-energy e(+)e(-) collider. The number baryons is determined by reconstructing recoiling D((*)-) pπ(+) system in events type pπ(+)Λ(c)(+). measured to be B(Λ(c)(+) pK(-)π(+)) = (6.84 ± 0.24(-0.27)(+0.21))%, where and second uncertainties are statistical systematic, respectively.