Search results for "D mesons"
showing 10 items of 13 documents
Search for CP violation using T-odd correlations in D-0 -> K+K-pi(+)pi(-) decays
2014
A search for $CP$ violation using $T$-odd correlations is performed using the four-body $D^0 \to K^+K^-\pi^+\pi^-$ decay, selected from semileptonic $B$ decays. The data sample corresponds to integrated luminosities of $1.0\,\text{fb}^{-1}$ and $2.0\,\text{fb}^{-1}$ recorded at the centre-of-mass energies of 7 TeV and 8 TeV, respectively. The $CP$-violating asymmetry $a_{CP}^{T\text{-odd}}$ is measured to be $(0.18\pm 0.29\text{(stat)}\pm 0.04\text{(syst)})\%$. Searches for $CP$ violation in different regions of phase space of the four-body decay, and as a function of the $D^0$ decay time, are also presented. No significant deviation from the $CP$ conservation hypothesis is found.
Measurement of D0, D+, D*+ and D+s production in pp collisions at √s = 5.02 TeV with ALICE
2019
The measurements of the production of prompt D0 , D+ , D∗+ , and D+s mesons in proton–proton (pp) collisions at s√=5.02 TeV with the ALICE detector at the Large Hadron Collider (LHC) are reported. D mesons were reconstructed at mid-rapidity ( |y|<0.5 ) via their hadronic decay channels D0→K−π+ , D+→K−π+π+ , D∗+→D0π+→K−π+π+ , D+s→ϕπ+→K+K−π+ , and their charge conjugates. The production cross sections were measured in the transverse momentum interval 0<pT<36 GeV/c for D0 , 1<pT<36 GeV/c for D+ and D∗+ , and in 2<pT<24 GeV/c for D+s mesons. Thanks to the higher integrated luminosity, an analysis in finer pT bins with respect to the previous measurements at s√=7 TeV was performed, allowing for …
D-Meson Azimuthal Anisotropy in Midcentral Pb-Pb Collisions at √sNN = 5.02 TeV
2018
The azimuthal anisotropy coefficient v 2 of prompt D 0 , D + , D * + , and D + s mesons was measured in midcentral (30%–50% centrality class) Pb-Pb collisions at a center-of-mass energy per nucleon pair √ s N N = 5.02 TeV , with the ALICE detector at the LHC. The D mesons were reconstructed via their hadronic decays at midrapidity, | y | < 0.8 , in the transverse momentum interval 1 < p T < 24 GeV / c . The measured D -meson v 2 has similar values as that of charged pions. The D + s v 2 , measured for the first time, is found to be compatible with that of nonstrange D mesons. The measurements are compared with theoretical calculations of charm-quark transport in a hydrodynamically e…
Measurement of azimuthal correlations of D mesons with charged particles in pp collisions at √s = 7 TeV and p-Pb collisions at √sNN = 5.02 TeV
2017
The azimuthal correlations of D mesons with charged particles were measured with the ALICE apparatus in pp collisions at √s = 7 TeV and p–Pb collisions at √sNN = 5.02 TeV at the Large Hadron Collider. D0, D+, and D∗+ mesons and their charge conjugates with transverse momentum 3 0.3 GeV/c. The yield of charged particles in the correlation peak induced by the jet containing the D meson and the peak width are compatible within uncertainties in the two collision systems. The data are described within uncertainties by Monte-Carlo simulations based on PYTHIA, POWHEG, and EPOS 3 event generators. peerReviewed
Precision measurement of D meson mass differences
2013
Using three- and four-body decays of D mesons produced in semileptonic b-hadron decays, precision measurements of D meson mass differences are made together with a measurement of the D-0 mass. The measurements are based on a dataset corresponding to an integrated luminosity of 1.0 fb(-1) collected in pp collisions at 7 TeV. Using the decay D-0 -> K+K-K-pi(+), the D-0 mass is measured to be M(D-0) = 1864.75 +/- 0.15 (stat) +/- 0.11 (syst) MeV/c(2). The mass differences M(D+) - M(D-0) = 4.76 +/- 0.12 (stat) +/- 0.07 (syst) MeV/c(2), M(D-s(+)) - M(D+) = 98.68 +/- 0.03 (stat) +/- 0.04 (syst) MeV/c(2) are measured using the D-0 -> K+K-pi(+)pi(-) and D-(s)(+) -> K+K-pi(+) modes.
Measurement of CP asymmetry in D 0 → K - K + and D 0 → π - πdecays
2014
Time-integrated $CP$ asymmetries in $D^0$ decays to the final states $K^- K^+$ and $\pi^- \pi^+$ are measured using proton-proton collisions corresponding to $3\mathrm{\,fb}^{-1}$ of integrated luminosity collected at centre-of-mass energies of $7\mathrm{\,Te\kern -0.1em V}$ and $8\mathrm{\,Te\kern -0.1em V}$. The $D^0$ mesons are produced in semileptonic $b$-hadron decays, where the charge of the accompanying muon is used to determine the initial flavour of the charm meson. The difference in $CP$ asymmetries between the two final states is measured to be \begin{align} \Delta A_{CP} = A_{CP}(K^-K^+)-A_{CP}(\pi^-\pi^+) = (+0.14 \pm 0.16\mathrm{\,(stat)} \pm 0.08\mathrm{\,(syst)})\% \ . \nonu…
Elliptic flow and $$R_{AA}$$ of $$\text {D}$$ mesons at FAIR comparing the UrQMD hybrid model and the coarse-graining approach
2019
The European physical journal / C Particles and fields C 79(1), 52 (2019). doi:10.1140/epjc/s10052-019-6537-6
Measurement of the mass of the D^{0} meson
2013
We report a measurement of the D-0 meson mass using the decay chain D* (2010) + -> D-0 pi(+) with D-0 -> K-K-K+pi(+). The data were recorded with the BABAR detector at center-of-mass energies at and near the Upsilon(4S) resonance, and correspond to an integrated luminosity of approximately 477 fb(-1). We obtain m(D-0) (1864: 841 +/- 0: 048 +/- 0: 063) MeV, where the quoted errors are statistical and systematic, respectively. The uncertainty of this measurement is half that of the best previous measurement.
Measurement of the mass and lifetime of the Ω(−)(b) baryon
2016
A proton-proton collision data sample, corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by LHCb at $\sqrt{s}=7$ and 8 TeV, is used to reconstruct $63\pm9$ $\Omega_b^-\to\Omega_c^0\pi^-$, $\Omega_c^0\to pK^-K^-\pi^+$ decays. Using the $\Xi_b^-\to\Xi_c^0\pi^-$, $\Xi_c^0\to pK^-K^-\pi^+$ decay mode for calibration, the lifetime ratio and absolute lifetime of the $\Omega_b^-$ baryon are measured to be \begin{align*} \frac{\tau_{\Omega_b^-}}{\tau_{\Xi_b^-}} &= 1.11\pm0.16\pm0.03, \\ \tau_{\Omega_b^-} &= 1.78\pm0.26\pm0.05\pm0.06~{\rm ps}, \end{align*} where the uncertainties are statistical, systematic and from the calibration mode (for $\tau_{\Omega_b^-}$ only). A measurement …
Exploring the D* rho system within QCD sum rules
2013
We present a study of the D* rho system made by using the method of QCD sum rules to determine the mass of possible resonances generated in the same system. Using isospin and spin projectors, we investigate the different configurations and obtain evidences for three D* mesons with isospin I = 1/2, spin S = 0, 1, 2 and with masses 2500 +/- 67, 2523 +/- 60, and 2439 +/- 119 MeV, respectively. The last state can be associated with D-2*(2460) ( spin 2) listed by the Particle Data Group, while one of the first two might be related to D* (2640), with unknown spin parity. In the case of I = 3/2 we also find evidences of three states with spin 0, 1, and 2, respectively, with masses 2467 +/- 82, 242…