R. Kulasiri
A5000703645- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Particle Accelerators and Free-Electron Lasers
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Particle Detector Development and Performance
- Black Holes and Theoretical Physics
- Superconducting Materials and Applications
- Atomic and Subatomic Physics Research
- Distributed and Parallel Computing Systems
- Particle accelerators and beam dynamics
- Nuclear physics research studies
- Neuroendocrine Tumor Research Advances
- Pulsars and Gravitational Waves Research
- Cold Atom Physics and Bose-Einstein Condensates
- Field-Flow Fractionation Techniques
- Cosmology and Gravitation Theories
- Numerical Methods and Algorithms
Kennesaw State University
2016-2023
University of Cincinnati
2001-2020
Duke University
2020
University of the Basque Country
2018-2020
University of Florida
2020
Chonnam National University
2018-2020
Beihang University
2018
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
2018
Laboratoire d’Annecy de Physique des Particules
2018
Institut National de Physique Nucléaire et de Physique des Particules
2018
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 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...
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 the observation of prompt J/psi via double cc; production from e+e- continuum. In this process one pair fragments into a meson while remaining either produces charmonium state or open charm. Both cases have been experimentally observed. find cross sections sigma[e+e- -->J/psieta(c)(gamma)]xB(eta(c)-->>or=4 charged)=(0.033(+0.007)(-0.006)+/-0.009) pb and sigma(e+e- -->J/psiD(*+)X)=(0.53(+0.19)(-0.15)+/-0.14) infer -->J/psicc;)/sigma(e+e- -->J/psiX)=0.59(+0.15)(-0.13)+/-0.12. These...
We report on a search for new resonant states in the process γγ→D¯¯¯D. A candidate C-even charmonium state is observed vicinity of 3.93 GeV/c2. The production rate and angular distribution γγ center-of-mass frame suggest that this previously unobserved χ′c2, 23P2 state.Received 15 December 2005DOI:https://doi.org/10.1103/PhysRevLett.96.082003©2006 American Physical Society
We present the first evidence of decay B -→ τ -ντ , using 414 fb -1 data collected at Υ(4S) resonance with Belle detector KEKB asymmetric-energy e + -collider.Events are tagged by fully reconstructing one mesons in hadronic modes.We detect signal a significance 3.5 standard deviations including systematics, and measure branching fraction to be B(B ) = (1.79+0.56 -0.49(stat) +0.46 -0.51 (syst)) × 10 -4 .This implies that fB 0.229 +0.036 -0.031 (stat) +0.034 -0.037 (syst) GeV is direct...
The Collins effect connects transverse quark spin with a measurable azimuthal dependence in the yield of hadronic fragments around quark's momentum vector. Using two different reconstruction methods, we find evidence statistically significant asymmetries for charged pion pairs e(+)e(-) annihilation at center-of-mass energy 10.52 GeV, which can be attributed to polarization primordial quarks. measurement was performed using sample 79 x 10(6) events collected Belle detector.
We present an improved measurement of the branching fraction for electroweak penguin process $B\ensuremath{\rightarrow}{X}_{s}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, where $\ensuremath{\ell}$ is electron or a muon and ${X}_{s}$ hadronic system containing $s$-quark. The based on sample $152\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $\ensuremath{\Upsilon}(4S)\ensuremath{\rightarrow}B\overline{B}$ events collected with Belle detector at KEKB energy asymmetric...
We present the results of a search for rare decays $B\to h\nu\overline{\nu}$, where $h$ stands $K^+,\:K^0_{\mathrm{S}},\:K^{\ast +},\:K^{\ast 0},\:\pi^+,\:\pi^0,\:\rho^+$ and $\rho^{0}$. The are obtained with $772\times10^{6}$ $B\overline{B}$ pairs collected Belle detector at KEKB $e^+ e^-$ collider. reconstruct one $B$ meson in semileptonic decay require single but nothing else on signal side. observe no significant set upper limits branching fractions. K^0_{\mathrm{S}}\nu\overline{\nu}$,...
We present a measurement of angular observables and test lepton flavor universality in the $B\to K^\ast \ell^+\ell^-$ decay, where $\ell$ is either $e$ or $μ$. The analysis performed on data sample corresponding to an integrated luminosity $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at $Υ(4S)$ resonance with Belle detector asymmetric-energy $e^+e^-$ collider KEKB. result consistent Standard Model (SM) expectations, largest discrepancy from SM prediction...
We present a new measurement of the Cabibbo-Kobayashi-Maskawa matrix element $|{V}_{cb}|$ from ${B}^{0}\ensuremath{\rightarrow}{D}^{*\ensuremath{-}}{\ensuremath{\ell}}^{+}{\ensuremath{\nu}}_{\ensuremath{\ell}}$ decays, reconstructed with full Belle data set $711\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ integrated luminosity. Two form factor parametrizations, originally conceived by Caprini-Lellouch-Neubert (CLN) and Boyd, Grinstein Lebed (BGL) groups, are used to extract product...
Using the entire Belle data sample of 980 ${\rm fb}^{-1}$ $e^+e^-$ collisions, we present results a study excited $\Omega_c$ charmed baryons in decay mode $\Xi_c^+K^-$. We show confirmation four five narrow states reported by LHCb Collaboration: $\Omega_c(3000)$ , $\Omega_c(3050)$, $\Omega_c(3066)$, and $\Omega_c(3090)$.
We report the observation of a narrow peak in K(S)K-pi(+) invariant mass distribution sample exclusive B-->KK(S)K-pi(+) decays collected with Belle detector at KEKB asymmetric e(+)e(-) collider. The measured is M=3654+/-6(stat)+/-8(syst) MeV/c(2), and we place 90% confidence level upper limit on width Gamma<55 MeV/c(2). properties agree heavy-quark potential model expectations for eta(c)(2S) meson, n=2 singlet S charmonium state.
We report the observation of an isotriplet excited charmed baryons, decaying into Lambda(+)(c)pi(-), Lambda(+)(c)pi(0), and Lambda(+)(c)pi(+). measure mass differences M(Lambda(+)(c)pi)-M(Lambda(+)(c)) widths to be 515.4(+3.2+2.1)(-3.1-6.0) MeV/c(2), 61(+18+22)(-13-13) MeV for neutral state; 505.4(+5.8+12.4)(-4.6-2.0) 62(+37+52)(-23-38) charged 514.5(+3.4+2.8)(-3.1-4.9) 75(+18+12)(-13-11) doubly state, where uncertainties are statistical systematic, respectively. These results obtained from...
We report results on a Dalitz analysis of three-body charmless ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}}$ decay including searches for direct $CP$ violation. the first observation ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{f}_{2}(1270){K}^{\ifmmode\pm\else\textpm\fi{}}$ with statistical significance above $6\ensuremath{\sigma}$. also...
We report a measurement of the exclusive e+e−→D(*)±D*∓ cross section as function center-of-mass energy near D(*)±D*∓ threshold with initial-state radiation. A partial reconstruction technique is used to increase efficiency and suppress background. The analysis based on data sample collected Belle detector an integrated luminosity 547.8 fb−1.Received 12 January 2007DOI:https://doi.org/10.1103/PhysRevLett.98.092001©2007 American Physical Society
We present improved measurements of $CP$-violation parameters in ${B}^{0}\ensuremath{\rightarrow}\ensuremath{\phi}{K}^{0}$, ${\ensuremath{\eta}}^{\ensuremath{'}}{K}^{0}$, ${K}_{S}^{0}{K}_{S}^{0}{K}_{S}^{0}$ decays based on a sample $535\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected at the $\ensuremath{\Upsilon}(4S)$ resonance with Belle detector KEKB energy-asymmetric ${e}^{+}{e}^{\ensuremath{-}}$ collider. obtain...
We perform a full amplitude analysis of the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}D\overline{D}$, where $D$ refers to either ${D}^{0}$ or ${D}^{+}$. A new charmoniumlike state ${X}^{*}(3860)$ that decays $D\overline{D}$ is observed with significance $6.5\ensuremath{\sigma}$. Its mass $({3862}_{\ensuremath{-}32}^{+26}{\text{ }}_{\ensuremath{-}13}^{+40})\text{ }\text{ }\mathrm{MeV}/{c}^{2}$, and its width $({201}_{\ensuremath{-}67}^{+154}{\text{...
Received 25 April 2018DOI:https://doi.org/10.1103/PhysRevD.97.099902© 2018 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasFlavor changing neutral currentsParticle decaysParticle interactionsParticles & Fields
We report on a high statistics measurement of the cross section process $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ in ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ invariant mass range $0.8\text{ }\text{ }\mathrm{GeV}/{c}^{2}<W<1.5\text{ }\mathrm{GeV}/{c}^{2}$ with $85.9\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data collected at $\sqrt{s}=10.58\text{ }\mathrm{GeV}$ and 10.52 GeV Belle detector. A...
We report the results of several studies Lambda(c)(+)pi(+)pi(-)X final state in continuum e(+)e(-) annihilation data collected by Belle detector. An analysis angular distributions Lambda(c)(2880)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decays strongly favors a Lambda(c)(2880)(+) spin assignment 5/2 over 3/2 or 1/2. find evidence for Lambda(c)(2880)(+)-->Sigma(c)(2520)(0,++)pi(+,-) decay and measure ratio partial widths Gamma(Sigma(c)(2520)pi)/Gamma(Sigma(c)(2455)pi)=0.225+/-0.062+/-0.025. This...
We report measurements of the properties D(+)(sJ)(2317) and D(+)(sJ)(2457) resonances produced in continuum e(+)e(-) annihilation near sqrt[s]=10.6 GeV. The analysis is based on an 86.9 fb(-1) data sample collected with Belle detector at KEKB. determine masses to be M(D(+)(sJ)(2317))=2317.2+/-0.5(stat)+/-0.9(syst) MeV/c(2) M(D(+)(sJ)(2457))=2456.5+/-1.3(stat)+/-1.3(syst) MeV/c(2). observe radiative decay mode D(+)(sJ)(2457)-->D(+)(s)gamma dipion D(+)(sJ)(2457)-->D(+)(s)pi(+)pi(-) their...
We present an analysis of charm quark fragmentation at 10.6 GeV, based on a data sample $103\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected by the Belle detector KEKB accelerator. consider into main charmed hadron ground states, namely ${D}^{0},{D}^{+},{D}_{s}^{+}$ and ${\ensuremath{\Lambda}}_{c}^{+}$, as well excited states ${D}^{*0}$ ${D}^{*+}$. The functions are important to measure they describe processes low energy scale, where calculations in perturbation theory lead large...