J. Dalseno
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Particle Detector Development and Performance
- Particle Accelerators and Free-Electron Lasers
- Black Holes and Theoretical Physics
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Nuclear physics research studies
- Radiation Detection and Scintillator Technologies
- Stochastic processes and statistical mechanics
- Cosmology and Gravitation Theories
- Distributed and Parallel Computing Systems
- Advanced NMR Techniques and Applications
- Particle accelerators and beam dynamics
- International Science and Diplomacy
- Astrophysics and Cosmic Phenomena
- Radioactive Decay and Measurement Techniques
- Markov Chains and Monte Carlo Methods
- Cold Atom Physics and Bose-Einstein Condensates
- Electron and X-Ray Spectroscopy Techniques
Universidade de Santiago de Compostela
2018-2025
Instituto de Física Corpuscular
2023
Universitat de València
2023
University of Chinese Academy of Sciences
2020-2023
European Organization for Nuclear Research
2015-2023
École Polytechnique Fédérale de Lausanne
2023
University of Zurich
2014-2023
Institute for Nuclear Research
2023
Kharkiv Institute of Physics and Technology
2023
University of Bristol
2014-2022
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 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.
A distinct peak is observed in the ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\psi}}^{\ensuremath{'}}$ invariant mass distribution near 4.43 GeV $B\ensuremath{\rightarrow}K{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\psi}}^{\ensuremath{'}}$ decays. fit using a Breit-Wigner resonance shape yields and width of $M=4433\ifmmode\pm\else\textpm\fi{}4(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}2(\mathrm{syst})\text{ }\text{ }\mathrm{MeV}$...
The Belle detector at the KEKB electron-positron collider has collected almost 1 billion Y(4S) events in its decade of operation. Super-KEKB, an upgrade is under construction, to increase luminosity by two orders magnitude during a three-year shutdown, with ultimate goal 8E35 /cm^2 /s luminosity. To exploit increased luminosity, been proposed. A new international collaboration Belle-II, being formed. Technical Design Report presents physics motivation, basic methods accelerator upgrade, as...
We study B→K(*)ℓ+ℓ− decays (ℓ=e, μ) based on a data sample of 657×106 BB¯ pairs collected with the Belle detector at KEKB e+e− collider. report differential branching fraction, isospin asymmetry, K* polarization, and forward-backward asymmetry (AFB) as functions q2=Mℓℓ2c2. The fitted AFB spectrum exceeds standard model expectation by 2.7 deviations. measured fractions are B(B→K*ℓ+ℓ−)=(10.7−1.0+1.1±0.9)×10−7 B(B→Kℓ+ℓ−)=(4.8−0.4+0.5±0.3)×10−7, where first errors statistical second systematic,...
This work is on the Physics of B Factories. Part A this book contains a brief description SLAC and KEK Factories as well their detectors, BaBar Belle, data taking related issues. discusses tools methods used by experiments in order to obtain results. The results themselves can be found C. Please note that version 3 archive auxiliary book. uses notation alpha, beta, gamma for angles Unitarity Triangle. nominal phi_1, phi_2 phi_3. cite Eur. Phys. J. C74 (2014) 3026.
The cross section for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\psi}(2S)$ between threshold and $\sqrt{s}=5.5\text{ }\text{ }\mathrm{GeV}$ is measured using $673\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data on off the $\ensuremath{\Upsilon}(4S)$ resonance collected with Belle detector at KEKB. Two resonant structures are observed in...
The cross section for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}J/\ensuremath{\psi}$ between 3.8 and $5.5\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ is measured using a $548\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected on or near the $\ensuremath{\Upsilon}(4S)$ resonance with Belle detector at KEKB. A peak $4.25\text{ }\mathrm{GeV}/{c}^{2}$, corresponding to so called $Y(4260)$, observed. In addition, there another...
We report the observation of a near-threshold enhancement in omegaJ/psi invariant mass distribution for exclusive B-->KomegaJ/psi decays. The results are obtained from 253 fb(-1) data sample that contains 275 x 10(6) BB pairs were collected near Upsilon(4S) resonance with Belle detector at KEKB asymmetric energy e(+)e(-) collider. statistical significance is estimated to be greater than 8sigma.
We report a measurement of the exclusive e+ e- -->Lambda+_(c)Lambda-_(c) cross section as function center-of-mass energy near Lambda+_(c)Lambda-_(c) threshold. A clear peak with significance 8.2sigma is observed in invariant mass distribution just above With an assumption resonance origin for peak, and width M=[4634 (+8)_(-7)(stat)(+5)_(-8)(syst)] MeV/c(2) Gamma_(tot)=[92 (+40)_(-24)(stat)(+10)_(-21)(syst)] MeV are determined. The analysis based on study events initial-state-radiation...
We report the first observation of a charmoniumlike state recoiling from J/psi in inclusive process e+e- -->J/psi+anything at mass (3.943+/-0.006+/-0.006) GeV/c{2}. also observe decay this into D*D[over ] and determine its intrinsic width to be less than 52 MeV/c{2} 90% C.L. These results are obtained 357 fb{-1} data sample collected with Belle detector near Upsilon(4S) resonance, KEKB asymmetric-energy collider.
We report the first observation of two charmed strange baryons that decay into Lambda(c)(+)Kappa(-)pi(+). The broader states is measured to have a mass 2978.5+/-2.1+/-2.0 MeV/c2 and width 43.5+/-7.5+/-7.0 MeV/c2. narrow state are be 3076.7+/-0.9+/-0.5 MeV/c;{2} 6.2+/-1.2+/-0.8 MeV/c2, respectively. also perform search for isospin partner Lambda(c)(+)Kappa(0)/(s)pi(-) observe significant signal at 3082.8+/-1.8+/-1.5 data used this analysis were accumulated or near Upsilon(4S) resonance, using...
We report the first observation of two resonance-like structures in pi+ chi_c1 invariant mass distribution near 4.1 GeV/c^2 exclusive B0-bar --> K- decays. From a Dalitz plot analysis which are represented by Breit-Wigner resonance amplitudes, we determine masses and widths of: M_1 = (4051 +-14 +20-41) MeV/c^2, Gamma_1 (82 +21-17 +47-22) MeV, M_2 (4248 +44-29 +180-35}) Gamma_2 =(177 +54-39 +316-61) MeV; product branching fractions BF(B0-bar Z+_1,2) x BF(Z+_1,2 chi_c1) (3.0 +1.5-0.8 +3.7-1.6)...
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 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 observe evidence for D0−¯¯¯D0 mixing by measuring the difference in apparent lifetime when a D0 meson decays to CP eigenstates K+K− and π+π− it final state K−π+. find relative of lifetimes yCP be [1.31±0.32(stat)±0.25(syst)]%, 3.2 standard deviations from zero. also search asymmetry between ¯¯¯D0 decays; no violation is found. These results are based on 540 fb−1 data recorded Belle detector at KEKB e+e− collider.Received 31 March 2007DOI:https://doi.org/10.1103/PhysRevLett.98.211803©2007...
We report a high-statistics measurement of the branching fraction for tau^- --> pi^- pi^0 nu_tau and invariant mass spectrum produced system using 72.2 fb^-1 data recorded with Belle detector at KEKB asymmetric-energy e^+ e^- collider. The obtained is (25.24 +/- 0.01 0.39)%, where first error statistical second systematic. unfolded used to determine resonance parameters rho(770), rho'(1450), rho"(1700) mesons. also use this estimate hadronic (2pi) contribution anomalous magnetic moment muon...
We report the first observation of a near-threshold enhancement in D(0)D[over](0)pi(0) system from B-->D(0)D[over](0)pi(0)Kappa decays using 414 fb(-1) data sample collected at Upsilon(4S) resonance. The peaks mass M=3875.2+/-0.7(+0.3)/(-1.6) +/-0.8 MeV/c2 and branching fraction for events peak is B(B-->D(0)D[over](0)pi(0)Kappa)=(1.22+/-0.31(+0.23)/(-0.30))x10(-4). were with Belle detector KEKB energy-asymmetric e+ e- collider.
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...