P. Bargassa
A5100708815- 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
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Medical Imaging Techniques and Applications
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Distributed and Parallel Computing Systems
- Radiation Detection and Scintillator Technologies
- Nuclear physics research studies
- Gamma-ray bursts and supernovae
- Nuclear reactor physics and engineering
- Advanced Data Storage Technologies
- Radiation Therapy and Dosimetry
- Cold Atom Physics and Bose-Einstein Condensates
- Particle accelerators and beam dynamics
- Stochastic processes and statistical mechanics
- Optical properties and cooling technologies in crystalline materials
- International Science and Diplomacy
Rudjer Boskovic Institute
2023-2025
LIP - Laboratory of Instrumentation and Experimental Particle Physics
2016-2025
Institute of High Energy Physics
2012-2024
A. Alikhanyan National Laboratory
2022-2024
University of Antwerp
2024
Joint Institute for Nuclear Research
2014-2023
University of Lisbon
2021
Universidad de Oviedo
2021
Instituto de Telecomunicações
2021
University of Oxford
2008-2020
We report the observation of X(3872) in J/psipi(+)pi(-) channel, with J/psi decaying to mu(+)mu(-), pp collisions at sqrt[s]=1.96 TeV. Using approximately 230 pb(-1) data collected Run II D0 detector, we observe 522+/-100 candidates. The mass difference between state and is measured be 774.9+/-3.1(stat)+/-3.0(syst) MeV/c(2). have investigated production decay characteristics find them similar those psi(2S) state.
We report observation of the electroweak production single top quarks in $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ based on $2.3\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data collected by D0 detector Fermilab Tevatron Collider. Using events containing an isolated electron or muon and missing transverse energy, together with jets originating from fragmentation $b$ quarks, we measure a cross section...
We report on a measurement of the inclusive jet cross section in pp[over ] collisions at center-of-mass energy sqrt[s]=1.96 TeV using data collected by D0 experiment Fermilab Tevatron Collider corresponding to an integrated luminosity 0.70 fb;{-1}. The cover transverse momenta from 50 600 GeV and rapidities range -2.4 2.4. Detailed studies correlations between systematic uncertainties momentum rapidity are presented, measurements found be good agreement with next-to-leading order QCD calculations.
We present the first measurement of integrated forward-backward charge asymmetry in top-quark–top-antiquark pair (t¯t) production proton-antiproton (p¯p) collisions lepton+jets final state. Using a b-jet tagging algorithm and kinematic reconstruction assuming t¯t+X decay, sample 0.9 fb−1 data, collected by D0 experiment at Fermilab Tevatron Collider, is used to measure for different jet multiplicities. The result also set upper limits on via Z′ resonance.Received 7 December...
From an analysis of the flavor-tagged decay ${B}_{s}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\phi}$ we obtain width difference between ${B}_{s}^{0}$ light and heavy mass eigenstates, $\ensuremath{\Delta}{\ensuremath{\Gamma}}_{s}=0.19\ifmmode\pm\else\textpm\fi{}0.07(\mathrm{stat}{)}_{\ensuremath{-}0.01}^{+0.02}(\mathrm{syst})\text{ }\text{ }{\mathrm{ps}}^{\ensuremath{-}1}$, $CP$-violating phase,...
We report results of a study the ${B}_{s}^{0}$ oscillation frequency using large sample semileptonic decays corresponding to approximately $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ integrated luminosity collected by D0 experiment at Fermilab Tevatron Collider in 2002--2006. The amplitude method gives lower limit on $14.8\text{ }{\mathrm{ps}}^{\ensuremath{-}1}$ 95% C.L. At $\ensuremath{\Delta}{m}_{s}=19\text{ }{\mathrm{ps}}^{\ensuremath{-}1}$, deviates from hypothesis $\mathcal{A}=0$...
We present a search for charged Higgs bosons in top quark decays. analyze the \eplus, \muplus, $ee$, $eμ$, $μμ$, \etau and \mutau final states from pair production events, using data about 1${\text{fb}}^{-1}$ of integrated luminosity recorded by \dzero experiment at Fermilab Tevatron Collider. consider different scenarios possible boson decays, one where decays purely hadronically into charm strange quark, another it $τ$ lepton neutrino third both appear. extract limits on branching ratio...
We present a measurement of the shape boson rapidity distribution for $p\overline{p}\ensuremath{\rightarrow}Z/{\ensuremath{\gamma}}^{*}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}+X$ events at center-of-mass energy 1.96 TeV. The is made with electron-positron mass $71<{M}_{ee}<111\text{ }\text{ }\mathrm{GeV}$ and uses $0.4\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data collected Fermilab Tevatron collider D0 detector. This significantly reduces uncertainties on in forward region...
We present first evidence for the production of single top quarks in D0 detector at Fermilab Tevatron ppbar collider. The standard model predicts that electroweak interaction can produce a quark together with an antibottom or light quark, without antiparticle partner is always produced from strong coupling processes. Top were observed pair 1995, and since then, has been searched ever larger datasets. In this analysis, we select events 0.9 fb-1 dataset have electron muon missing transverse...
We present a measurement of the shape $Z/{\ensuremath{\gamma}}^{*}$ boson transverse momentum (${q}_{T}$) distribution in $p\overline{p}\ensuremath{\rightarrow}Z/{\ensuremath{\gamma}}^{*}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}+X$ events at center-of-mass energy 1.96 TeV using $0.98\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data collected with D0 detector Fermilab Tevatron collider. The are found to be consistent resummation prediction low ${q}_{T}$, but above perturbative...
The D0 Collaboration presents first evidence for the production of single top quarks at Fermilab Tevatron pp¯ collider. Using a 0.9 fb−1 dataset, we apply multivariate analysis to separate signal from background and measure σ(pp¯→tb+X,tqb+X)=4.9±1.4 pb. probability cross section this value or higher in absence is 0.035%, corresponding 3.4 standard deviation significance. We use measurement directly determine Cabibbo-Kobayashi-Maskawa matrix element that describes Wtb coupling find...
A data sample corresponding to an integrated luminosity of 2.1 fb-1 collected by the D0 detector at Fermilab Tevatron Collider was analyzed search for squarks and gluinos produced in ppbar collisions a center-of-mass energy 1.96 TeV. No evidence production such particles observed topologies involving jets missing transverse energy, 95% C.L. lower limits 379 GeV 308 were set on squark gluino masses, respectively, within framework minimal supergravity with tan(beta)=3, A0=0, mu<0. The...
We report the first direct observation of strange $b$ baryon ${\ensuremath{\Xi}}_{b}^{\ensuremath{-}}({\overline{\ensuremath{\Xi}}}_{b}^{+})$. reconstruct decay ${\ensuremath{\Xi}}_{b}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}{\ensuremath{\Xi}}^{\ensuremath{-}}$, with $J/\ensuremath{\psi}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$, and...
We combine measurements of the top quark pair production cross section in p¯p collisions ℓ+jets, ℓℓ, and τℓ final states (where ℓ is an electron or muon) at a center mass energy √s=1.96 TeV 1 fb−1 data collected with D0 detector. For 170 GeV/c2, we obtain σt¯t=8.18+0.98−0.87 pb agreement theoretical prediction. Based on predictions from higher order quantum chromodynamics, extract for combined t¯t section, consistent world average mass. In addition, ratios sections different are used to set...
A fully reconstructed ${B}_{c}\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\pi}$ signal is observed with the D0 detector at Fermilab Tevatron $p\overline{p}$ collider using $1.3\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity. The consists $54\ifmmode\pm\else\textpm\fi{}12$ candidates a significance that exceeds 5 standard deviations, and confirms earlier observations this decay. measured mass ${B}_{c}$ meson...
We present the first measurement of dijet angular distributions in pp collisions at square root(s) = 1.96 TeV Fermilab Tevatron Collider. The is based on a dataset corresponding to an integrated luminosity 0.7 fb(-1) collected with D0 detector. Dijet have been measured over range masses, from 0.25 above 1.1 TeV. data are good agreement predictions perturbative QCD and used constrain new physics models including quark compositeness, large extra dimensions, TeV(-1) scale dimensions. For all...
We present a measurement of the $W$ boson mass in $W\ensuremath{\rightarrow}e\ensuremath{\nu}$ decays using $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data collected with D0 detector during Run II Fermilab Tevatron collider. With sample 499830 candidate events, we measure ${M}_{W}=80.401\ifmmode\pm\else\textpm\fi{}0.043\text{ }\mathrm{GeV}$. This is most precise from single experiment.
The cross section for the inclusive production of isolated photons has been measured in pp¯ collisions at s=1.96TeV with DØ detector Fermilab Tevatron Collider. span transverse momenta 23 to 300 GeV and have pseudorapidity |η|<0.9. is compared results from two next-to-leading order perturbative QCD calculations. theoretical predictions agree measurement within uncertainties.
Correlations in the azimuthal angle between two largest transverse momentum jets have been measured using D0 detector $p\overline{p}$ collisions at a center-of-mass energy $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$. The analysis is based on an inclusive dijet event sample central rapidity region corresponding to integrated luminosity of $150\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$. Azimuthal correlations are stronger larger momenta. These well described perturbative QCD next-to-leading...
We report the observation of doubly strange b baryon Ω−b in decay channel Ω−b→J/ψΩ−, with J/ψ→μ+μ− and Ω−→ΛK−→(pπ−)K−, p¯p collisions at √s=1.96 TeV. Using approximately 1.3 fb−1 data collected D0 detector Fermilab Tevatron Collider, we observe 17.8±4.9(stat)±0.8(syst) signal events a mass 6.165±0.010(stat)±0.013(syst) GeV. The significance observed is 5.4σ, corresponding to probability 6.7×10−8 it arising from background fluctuation.Received 29 August...
We present a measurement of the muon charge asymmetry from W boson decays using 0.3 fb−1 data collected at s=1.96 GeV between 2002 and 2004 with D0 detector Fermilab Tevatron pp¯ Collider. compare our findings expectations next-to-leading-order calculations performed CTEQ6.1M MRST04 NLO parton distribution functions. Our can be used to constrain future function fits.Received 27 September 2007DOI:https://doi.org/10.1103/PhysRevD.77.011106©2008 American Physical Society
We report the direct observation of excited L=1 state B_(s2)(*) in fully reconstructed decays to B+K-. The mass meson is measured be 5839.6+/-1.1(stat)+/-0.7(syst) MeV/c(2), and its production rate relative B+ [1.15+/-0.23(stat)+/-0.13(syst)]%.