A5065782890- 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
- Particle Accelerators and Free-Electron Lasers
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Radiation Detection and Scintillator Technologies
- Nuclear physics research studies
- Cosmology and Gravitation Theories
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Advanced Data Storage Technologies
- Distributed and Parallel Computing Systems
- Advanced NMR Techniques and Applications
- Lanthanide and Transition Metal Complexes
- Muon and positron interactions and applications
- CCD and CMOS Imaging Sensors
- Pulsars and Gravitational Waves Research
Indian Institute of Technology Guwahati
2016-2025
Korea Institute of Science & Technology Information
2023
Laboratoire d’Annecy de Physique des Particules
2005-2018
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
Austrian Academy of Sciences
2018
Institute of High Energy Physics
2018
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 a measurement of the branching fraction ratios R(D(*)) Bbar -> D(*) tau- nubar_tau relative to D()* l- nubar_l (where l = e or mu) using full Belle data sample 772 x 10^6 BBbar pairs collected at Y(4S) resonance with detector KEKB asymmetric-energy e+e- collider. The measured values are R(D)= 0.375 +- 0.064(stat.) 0.026(syst.) and R(D*) 0.293 0.038(stat.) 0.015(syst.). analysis uses hadronic reconstruction tag-side B meson purely leptonic tau decays. results consistent earlier...
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...
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 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...
Experiment E949 at Brookhaven National Laboratory has observed three new events consistent with the decay K+→π+ν¯ν in pion momentum region 140<Pπ<199 MeV/c an exposure of 1.71×1012 stopped kaons estimated total background 0.93±0.17(stat)+0.32−0.24(syst) events. This brings number to seven. Combining this observation previous results, assuming spectrum predicted by standard model, results a branching ratio B(K+→π+ν¯ν)=(1.73+1.15−1.05)×10−10. An interpretation for alternative models...
We present a measurement of angular observables and test lepton flavor universality in the $B\ensuremath{\rightarrow}{K}^{*}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ decay, where $\ensuremath{\ell}$ is either $e$ or $\ensuremath{\mu}$. The analysis performed on data sample corresponding to an integrated luminosity $711\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ containing $772\ifmmode\times\else\texttimes\fi{}1{0}^{6}$ $B\overline{B}$ pairs, collected at...
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...
The preponderance of matter over antimatter in the early universe, dynamics supernovae that produced heavy elements necessary for life, and whether protons eventually decay—these mysteries at forefront particle physics astrophysics are key to understanding evolution our its current state, eventual fate. Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated addressing these questions as it searches leptonic charge-parity symmetry violation, stands...
The NOvA experiment has made a $4.4\sigma$-significant observation of $\bar\nu_{e}$ appearance in 2 GeV $\bar\nu_{\mu}$ beam at distance 810 km. Using $12.33\times10^{20}$ protons on target delivered to the Fermilab NuMI neutrino beamline, recorded 27 $\bar\nu_{\mu} \rightarrow \bar\nu_{e}$ candidates with background 10.3 and 102 \bar\nu_{\mu}$ candidates. This new antineutrino data is combined measure oscillation parameters $|\Delta m^2_{32}| = 2.48^{+0.11}_{-0.06}\times10^{-3}$ eV$^2/c^4$,...
We report results from the first search for νμ→νe transitions by NOvA experiment. In an exposure equivalent to 2.74×1020 protons on target in upgraded NuMI beam at Fermilab, we observe 6 events Far Detector, compared a background expectation of 0.99±0.11(syst) based Near Detector measurement. A secondary analysis observes 11 with 1.07±0.14(syst). The 3.3σ excess observed primary disfavors 0.1π<δCP<0.5π inverted mass hierarchy 90% C.L.Received 19 January...
The experimental results on the ratios of branching fractions R(D)=B(B[over ¯]→Dτ^{-}ν[over ¯]_{τ})/B(B[over ¯]→Dℓ^{-}ν[over ¯]_{ℓ}) and R(D^{*})=B(B[over ¯]→D^{*}τ^{-}ν[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}), where ℓ denotes an electron or a muon, show long-standing discrepancy with standard model predictions, might hint at violation lepton flavor universality. We report new simultaneous measurement R(D) R(D^{*}), based data sample containing 772×10^{6} BB[over ¯] events recorded ϒ(4S) resonance...
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....
The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is determined, based on a full simulation, reconstruction, and event selection far detector simulation parameterized analysis near detector. Detailed uncertainties due flux prediction, interaction model, effects are included. DUNE will resolve mass ordering precision 5$\sigma$, for all $\delta_{\mathrm{CP}}$ values, after 2 years running with nominal design beam configuration. It has potential observe...
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 present updated results from the NOvA experiment for $\nu_\mu\rightarrow\nu_\mu$ and $\nu_\mu\rightarrow\nu_e$ oscillations an exposure of $8.85\times10^{20}$ protons on target, which represents increase 46% compared to our previous publication. The utilize significant improvements in both simulations analysis data. A joint fit data $\nu_\mu$ disappearance $\nu_e$ appearance gives best point as normal mass hierarchy, $\Delta m^2_{32} = 2.44\times 10^{-3}{{\rm eV}^2}/c^4$,...
The Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are forefront of astrophysics and particle physics research. DUNE will study pertaining to preponderance matter over antimatter in early universe, dynamics supernovae, subtleties neutrino interaction physics, a number beyond Standard Model topics accessible powerful beam. A critical component program involves changes beam neutrinos,...
The preponderance of matter over antimatter in the early universe, dynamics supernovae that produced heavy elements necessary for life, and whether protons eventually decay—these mysteries at forefront particle physics astrophysics are key to understanding evolution our its current state, eventual fate. DUNE is an international world-class experiment dedicated addressing these questions as it searches leptonic charge-parity symmetry violation, stands ready capture supernova neutrino bursts,...
The Deep Underground Neutrino Experiment (DUNE), a 40-kton underground liquid argon time projection chamber experiment, will be sensitive to the electron-neutrino flavor component of burst neutrinos expected from next Galactic core-collapse supernova. Such an observation bring unique insight into astrophysics core collapse as well properties neutrinos. general capabilities DUNE for neutrino detection in relevant few- few-tens-of-MeV energy range described. As example, DUNE's ability...
We search for the rare decay <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msup><a:mi>B</a:mi><a:mo>+</a:mo></a:msup><a:mo stretchy="false">→</a:mo><a:msup><a:mi>K</a:mi><a:mo>+</a:mo></a:msup><a:mi>ν</a:mi><a:mover accent="true"><a:mi>ν</a:mi><a:mo stretchy="false">¯</a:mo></a:mover></a:math> in a <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:mn>362</f:mn><f:mtext> </f:mtext><f:mtext>...
Three events for the decay K+→π+ν¯ν have been observed in pion momentum region below K+→π+π0 peak, 140<Pπ<199 MeV/c, with an estimated background of 0.93±0.17(stat.)+0.32−0.24(syst.) events. Combining this observation previously reported results yields a branching ratio B(K+→π+ν¯ν)=(1.73+1.15−1.05)×10−10 consistent standard model prediction.Received 18 August 2008DOI:https://doi.org/10.1103/PhysRevLett.101.191802©2008 American Physical Society
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...