S. Chakrabarti
A5090573028- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Ionosphere and magnetosphere dynamics
- Atmospheric Ozone and Climate
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Optical Systems and Laser Technology
- Particle Detector Development and Performance
- Stellar, planetary, and galactic studies
- Earthquake Detection and Analysis
- Adaptive optics and wavefront sensing
- Astronomy and Astrophysical Research
- Photocathodes and Microchannel Plates
- Calibration and Measurement Techniques
- Planetary Science and Exploration
- Dark Matter and Cosmic Phenomena
- Spacecraft Design and Technology
- Geophysics and Gravity Measurements
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Cosmology and Gravitation Theories
- GNSS positioning and interference
- Atmospheric and Environmental Gas Dynamics
University of Massachusetts Lowell
2015-2024
Indian Centre for Space Physics
2005-2022
State University of New York
2009-2017
Stony Brook University
2009-2017
S.N. Bose National Centre for Basic Sciences
2005-2017
Universidade Federal do ABC
2010-2016
University of Science and Technology of China
2011-2016
Charles University
2010-2016
Institut National de Physique Nucléaire et de Physique des Particules
2006-2016
Centre National de la Recherche Scientifique
2010-2016
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 a measurement of forward-backward asymmetry in top quark-antiquark production proton-antiproton collisions the final state containing lepton and at least four jets. Using dataset corresponding to an integrated luminosity $5.4\,\mathrm {fb}^{-1}$, collected by \DZ\ experiment Fermilab Tevatron Collider, we measure \ttbar\ be $(9.2 \pm 3.7)$% reconstruction level. When corrected for detector acceptance resolution, is found $(19.6 6.5)$%. also based on from quark decay, $(15.2...
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 measure the charge asymmetry A ≡ (N++ - N--)/(N++ + N--) of like-sign dimuon events in 6.1 fb-1 pp collisions recorded with D0 detector at a center-of-mass energy square root(s) = 1.96 TeV Fermilab Tevatron collider. From we extract semileptonic b-hadron decays: A(sl)(b) -0.009 57 ± 0.002 51(stat) 0.001 46(sys). It differs by 3.2 standard deviations from model prediction A(sl)(b)(SM) (-2.3(-0.6)(+0.5)) × 10(-4), and provides first evidence anomalous CP violation mixing neutral B mesons.
We have used a sample of $\ensuremath{\gamma}+3$ jets events collected by the D0 experiment with an integrated luminosity about $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ to determine fraction double parton scattering (${f}_{\mathrm{DP}}$) in single $p\overline{p}$ collision at $\sqrt{s}=1.96\text{ }\mathrm{TeV}$. The DP and effective cross section (${\ensuremath{\sigma}}_{\mathrm{eff}}$), process-independent scale parameter related density inside nucleon, are measured three...
We report evidence of a narrow structure, $X(5568)$, in the decay sequence $X(5568) \rightarrow B_s^0 π^{\pm}$, $B_s^0 J/ψϕ$, $J/ψ\rightarrow μ^+ μ^-$, $ϕ\rightarrow K^+K^-$. This is for first instance hadronic state with valence quarks four different flavors. The mass and natural width this are measured to be $m = 5567.8 \pm 2.9 {\rm \thinspace (stat)} ^{+0.9}_{-1.9} (syst)}$ MeV/$c^2$ $Γ= 21.9 6.4 ^{+5.0}_{-2.5} (syst)} $ MeV/$c^2$. If B_s^* π^{\pm} γπ^{\pm}$ an unseen $γ$, $m(X(5568))$...
We measure the charge asymmetry $A$ of like-sign dimuon events in 6.1 fb$^{-1}$ $p\bar{p}$ collisions recorded with D0 detector at a center-of-mass energy $\sqrt{s} = 1.96$ TeV Fermilab Tevatron collider. From $A$, we extract semileptonic $b$-hadron decays: $\aslb -0.00957 \pm 0.00251 ({\rm stat}) 0.00146 syst})$. This result differs by 3.2 standard deviations from model prediction $\aslb(SM) (-2.3^{+0.5}_{-0.6}) \times 10^{-4}$ and provides first evidence anomalous CP-violation mixing...
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 an updated measurement of the anomalous like-sign dimuon charge asymmetry Aslb for semi-leptonic $b$-hadron decays in 9.0 fb^-1 p pbar collisions recorded with D0 detector at a center-of-mass energy sqrt{s} = 1.96 TeV Fermilab Tevatron collider. obtain (-0.787 +- 0.172(stat) 0.093 (syst))%. This result differs by 3.9 standard deviations from prediction model and provides evidence anomalously large CP violation neutral B decay. The dependence on muon impact parameter is consistent...
We present the results of a search for flavor changing neutral current decay B_s^0->mu^+mu^- using 6.1 fb^-1 ppbar collisions at sqrt(s) = 1.96 TeV collected by D0 experiment Fermilab Tevatron Collider. The observed number B_s^0 candidates is consistent with background expectations. resulting upper limit on branching fraction BR(B_s^0->mu^+mu^-) < 5.1 x 10^-8 95% C.L. This factor 2.4 better than that previous analysis and best to date.
We present a measurement of the W boson mass using data corresponding to 4.3fb^-1 integrated luminosity collected with D0 detector during Run II at Fermilab Tevatron p\bar{p} collider. With sample 1,677,394 -> e\nu candidate events, we measure M_W = 80.367 +/- 0.026 GeV. This result is combined an earlier determined independent sample, 1fb^-1 luminosity, yield 80.375 0.023
We report an updated measurement of the $CP$-violating phase, ${\ensuremath{\phi}}_{s}^{J/\ensuremath{\psi}\ensuremath{\phi}}$, and decay-width difference for two mass eigenstates, $\ensuremath{\Delta}{\ensuremath{\Gamma}}_{s}$, from flavor-tagged decay ${B}_{s}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}\ensuremath{\phi}$. The data sample corresponds to integrated luminosity $8.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ accumulated with D0 detector using $p\overline{p}$ collisions...
We present a measurement of the forward–backward asymmetry in top quark–antiquark production using full Tevatron Run II data set collected by D0 experiment at Fermilab. The is performed lepton+jets final states new kinematic fitting algorithm for events with four or more jets and partial reconstruction only three jets. Corrected detector acceptance resolution effects, evaluated to be AFB=(10.6±3.0)%. Results are consistent standard model predictions which range from 5.0% 8.8%. also...
We present the observation of doubly-produced $J/\psi$ mesons with D0 detector at Fermilab in $p\bar{p}$ collisions $\sqrt{s}=1.96$ TeV. The production cross section for both singly and is measured using a sample an integrated luminosity 8.1fb$^{-1}$. For first time, double separated into contributions due to single parton scatterings. Using these measurements, we determine effective $\sigma_{eff}$, parameter characterizing spatial area parton-parton interactions related density inside nucleon.
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...
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...