Search results for "Identification"
showing 10 items of 1600 documents
On reference star recognition and identification
2014
The paper deals with a research in the area of automation of positional star observations. In order to fully employ recent progress in imaging technologies, star image recognition and reference star identification process should gain comparable level of automation. A software package for this purpose has been developed in the Institute of Geodesy of the University of Latvia. It is capable of near-real-time image processing, star identification and astrometric position determination.
Improved measurement of time-dependentCPasymmetries and theCP-odd fraction in the decayB0→D*+D*−
2007
We present an updated measurement of time-dependent CP asymmetries and the CP-odd fraction in the decay B0-->D*+D*- using 232x10(6)BB pairs collected by the BABAR detector at the SLAC PEP-II B factory. We determine the CP-odd fraction to be 0.125+/-0.044(stat)+/-0.007(syst). The time-dependent CP asymmetry parameters C+ and S+ are determined to be 0.06+/-0.17(stat)+/-0.03(syst) and -0.75+/-0.25(stat)+/-0.03(syst), respectively. The standard model predicts these parameters to be 0 and -sin2beta, respectively, in the absence of penguin amplitude contributions.
Search for prompt production ofχcandX(3872)ine+e−annihilations
2007
We have searched for prompt production of χc1, χc2 and X(3872) in continuum e+e- annihilations using a 386fb-1 data sample collected around s=10.6GeV with the BABAR detector using the γJ/ψ decay mode. After accounting for the feed-down from ψ(2S)→γχc1,2, no significant signal for prompt χc1,2 production is observed. We present improved upper limits at 90% confidence level on the production cross sections of 77fb for χc1 and 79fb for χc2, for events where the χc momentum exceeds 2.0 GeV and there are at least three additional charged tracks. These limits are consistent with NRQCD predictions. We also set an upper limit on the prompt production of X(3872) through the decay X(3872)→γJ/ψ. © 200…
Measurement of theB¯0→D*+ℓ−ν¯ℓdecay rate and|Vcb|
2005
We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ based on a sample of about 53,700 \mbox{$\Bzb \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell}$} decays observed by the \babar\ detector. We obtain the branching fraction averaged over $\ell = e,\mu$, ${\cal B}(\Bzb \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell}) = (4.90 \pm 0.07\mathrm{(stat.)}^{+0.36}_{-0.35}\mathrm{(syst.)})\%$. We measure the differential decay rate as a function of $w$, the relativistic boost $\gamma$ of the $D^{*+}$ in the ${\Bzb}$ rest frame. By extrapolating $d\Gamma/dw$ to the kinematic limit $w \rightarrow 1$, we extract the product of $|V_{cb}|$ and the axial form factor ${\cal A}_1(w=1)$. …
Multivariate searches for single top quark production with the D0 detector
2007
We present a search for electroweak production of single top quarks in the s-channel (p-pbar -> t bbar + X) and t-channel (p-pbar -> tq bbar + X) modes. We have analyzed 230 pb^(-1) of data collected with the D0 detector at the Fermilab Tevatron collider at a center-of-mass energy of sqrt(s) = 1.96 TeV. Two separate analysis methods are used: neural networks and a cut-based analysis. No evidence for a single top quark signal is found. We set 95% confidence level upper limits on the production cross sections using Bayesian statistics, based on event counts and binned likelihoods formed from the neural network output. The limits from the neural network (cut-based) analysis are 6.4 pb (1…
Study of theτ−→3h−2h+ντdecay
2005
The branching fraction of the tau- --> 3h- 2h+ nu decay (h= pi, kaon) is measured with the BaBar detector to be (8.56 +/- 0.05 +/- 0.42)E-04 where the first error is statistical and the second systematic. The observed structure of this decay is significantly different from the phase space prediction, with the rho resonance playing a strong role. The decay tau- --> f1 pi nu with the f1 meson decaying to four charged pions, is observed and the branching fraction is measured to be (3.9 +/- 0.7 +/- 0.5)E-04.
Centrality dependence of the nuclear modification factor of charged pions, kaons, and protons in Pb-Pb collisions atsNN=2.76TeV
2016
Transverse momentum (pT) spectra of pions, kaons, and protons up to pT=20GeV/c have been measured in Pb-Pb collisions at √sNN=2.76TeV using the ALICE detector for six different centrality classes covering 0%–80%. The proton-to-pion and the kaon-to-pion ratios both show a distinct peak at pT≈3GeV/c in central Pb-Pb collisions that decreases for more peripheral collisions. For pT>10GeV/c, the nuclear modification factor is found to be the same for all three particle species in each centrality interval within systematic uncertainties of 10%–20%. This suggests there is no direct interplay between the energy loss in the medium and the particle species composition in the hard core of the quenched…
Identification of Bending Modes of Vibration in Rails by a Laser Doppler Vibrometer on a Moving Platform
2020
This paper introduces a method to identify the bending modes of vibration of railway tracks by using a laser Doppler vibrometer (LDV) mounted on a moving platform. Two sets of experiments were conducted at Transportation Technology Center Inc. (TTCI) in Pueblo Colorado, in order to validate the proposed method. First, the bending vibration modes were identified using the signals collected from a rail span (rail section between two consecutive sleepers) by accelerometers under moving car excitation. Then, vibration measurements from rail spans were obtained by using an LDV mounted on the moving railcar. All tests were carried out at four different rail car speeds: 8 km/h (5 mph), 16 km/h (10…
Recoil-isomer tagging techniques at RITU
2003
Techniques have been developed to study isomeric states in nuclei with the use of RITU (gas filled separator) at the University of Jyvaskyla. The first was the recoil-isomer tagging technique initially, utilised by D.M. Cullen to study the K π = 8− isomeric state in 138Gd [1]. The juro-sphere array was employed in conjunction with ritu and a focal plane array which consisted of several Compton-suppressed Germanium detectors, placed in close geometry around a multi wire proportional counter (mwpc) and a silicon strip detector used for the implantation of recoiling nuclei. This technique correlates prompt and delayed γ-ray transitions across isomeric states and identifies the lifetime of the …
Lifetime measurements of excited states in neutron-rich Ti53 : Benchmarking effective shell-model interactions
2020
Level lifetimes of the yrast (5/2(-)) to 13/2(-) states in the neutron-rich nucleus Ti-53, produced in a multinucleon-transfer reaction, have been measured for the first time. The recoil distance Doppler-shift method was employed and lifetimes of the excited states were extracted by a lineshape analysis aided by GEANT4-based Monte-Carlo simulations. The experiment was performed at the Grand Accelerateur National d'Ions Lourds facility in Caen, France, by using the Advanced Gamma Tracking Array for the gamma-ray detection coupled to the large-acceptance variable mode spectrometer for an event-by-event particle identification and the Cologne plunger for deep-inelastic reactions. Reduced trans…