0000000000132294
AUTHOR
L. W. Wiggers
showing 14 related works from this author
A reanalysis of branching fractions of charmed mesonsD 0,D + andD s +
1992
We combine highly complementary information on branching fractions of charmed mesonsD0,D+ andDs+ coming from two experiments both yielding doublecharm samples. The NA 32 experiment provided exclusive branching fractions for channels with at least two charged decay products while a recent Mark III paper provides results on inclusive charm decay properties. The knowledge of channels withK0's in the former is used to recalculate the charged multiplicity distribution in the latter. We obtain 〈nch〉=2.25±0.08 forD0, 〈nch〉=1.96±0.08 forD+ and 〈nch〉=2.41±0.38 forDs+. In turn the knowledge of the charged multiplicity improves the overall normalization of exclusive branching fractions. This reanalysi…
Measurement of the mass and width of the charmed meson D∗+ (2010)
1992
Abstract Using a high-resolution silicon vertex detector we have observed a very clean signal of 127 D∗+. After a careful study of the experimental resolution of our apparatus we have measured m( D ∗++ )−m( D 0 ) = 145.39±0.06±0.03 MeV . We have also obtained a 90% CL upper limit to γ(D∗+) of 131 keV.
Production of the charmed baryon $\Lambda_{c}^{+}$ in $\pi^{-}$Cu and K$^{-}$Cu interactions at 230 GeV
1990
Abstract We present results from the NA32 experiment at CERN on the production characteristics of the charmed baryon Λ+c in 230 GeV π−Cu and K−Cu interactions. A high resolution vertex detector consisting of change-coupled devices and silicon microstrip detectors allowed the selection of a very clean sample of 154 Λ+c → pK−π+ (and charge conjugate) decays. Results on differential and integrated cross sections are given.
$$\bar K^{0*} (892)$$ andK 0*(892) production at lowp t and the quark parton model
1990
Data on the production of the neutralK*(892) resonances at lowpt by 200 GeVK− and π− is compared with the predictions of various models based on the quark parton model of hadrons.
Measurement of the mass and lifetime of the charmed strange baryon $\Xi_{c}^{+}$
1989
Abstract We have observed six unambiguous decays of the charmed strange baryon Ξc+ (or charge conjugate Ξc−) in the 230 GeV/c negative pions or kaons on a copper target at the CERN SPS using silicon microstrip detectors and charge-coupled devices for vertex reconstruction. Three of them have been reconstructed through the decay chain Ξc+ →Ξ−π+π+, Ξ− →Λ0π−, Λ0 →pπ− and the other three through the decay chain Ξc+ →Σ+K−π+ →pπ0. We present our measurements of the mass, lifetime and production cross-section of the Ξc+, as well as of the branching ration for the two decay modes.
Production properties ofD 0,D +,D *+ andD s + in 230 GeV/c? ? andK ?-Cu interactions
1991
We have studied the hadronic production of charmed mesons in the NA 32 experiment at CERN. A special trigger together with a high resolution vertex detector consisting of charge coupled devices and silicon microstrip detectors allowed the selection of very clean samples of charmed mesons. We have collected 852 fully reconstructed decays: 60D + →K + K −π+, 543D°→K −π+ andK −π+π−π+ as well as 249D +→K −π+π+ (or charge conjugate). 147 mesons out of our $${{D^0 } \mathord{\left/ {\vphantom {{D^0 } {\bar D^0 }}} \right. \kern-\nulldelimiterspace} {\bar D^0 }}$$ sample were produced via chargedD * state. For all charmed mesons we determine the total production cross-section and study thex F andp …
Lifetimes of charged and neutralD mesons
1987
We have measured the lifetimes of hadronically produced charged and neutralD mesons using silicon microstrip detectors and an active silicon target in the NA32 spectrometer at the CERN SPS. We obtainτD± = (10.9±1.51.9)·10−13s andτD(−)10 = (4.2±0.5)·10−13s based on 59 and 90 fully reconstructed decays respectively, giving a ratioτD±/τD(−)10 of 2.6 ±0.5.
Measurement of the masses and lifetimes of the charmed mesonsD 0,D + andD s +
1990
We present the final results on the measurement of the masses and lifetimes of the mesonsD0,D+ andD s + in the NA32 experiment at the CERN SPS, using silicon microstrip detectors and charge-coupled devices for vertex reconstruction. We measure the following lifetimes:\(\tau _{D^0 } = 3.88 \pm _{0.21}^{0.23} \cdot 10^{ - 13} s\) using a sample of 479D°→K−π+π−π+ and 162D°→K−π+ decays;\(\tau _{D^ + } = 10.5 \pm _{0.72}^{0.77} \cdot 10^{ - 13} s\) with a sample of 317D+→K−π+π+ decays;\(\tau _{D_s^ + } = 4.69 \pm _{0.86}^{1.02} \cdot 10^{ - 13} s\) with a sample of 54D s + →K+K−π+ decays. We measure the following masses:mD0=1864.6±0.3±1.0 MeV,mD+=1870.0±0.5±1.0 MeV and\(m_{D_s^ + } \)=1967.0±1.0…
A study of λ+c decays into pK−π+, pK−π+π0and pK−π+π0π0
1993
Abstract In the CERN NA32 experiment a high-resolution silicon vertex detector and a purely topological approach were used to collect a clean sample of λ + c decays into pK − π + with or without additional neutral particles. We study the subresonant structure of the λ c + peak obtaining BR (λ c + → p K ∗0 (892)) = 0.35 −0.07 +0.06 ±0.03 with respect to the total λ c + → pK − π + decay. We also determine branching ratios for some channels with neutral decay products, namely BR( λ c + → pK − π + π 0 ) = 0.73±0.12±0.05 and BR( λ c + → pK − π + π 0 π 0 = 0.16±0.07±0.03, again with respect to the total λ c + → pK − π + decay.
Charmed pair correlations in π−Cu interactions at 230 GeV/c
1993
Abstract In the CERN NA32 experiment a high-resolution silicon vertex detector and a purely topological approach were used to collect 557 events consistent with associated charm production, both decay vertices being observed. The pseudorapidity gap distribution appears to be nearly independent of the nature of the charmed hadrons. This distribution is reasonably consistent with the next-to-leading order QCD calculations. However the azimuthal-angle distribution is significantly broader than the above predictions.
First measurement of the lifetime of the charmed strange baryon Ξc0
1990
Abstract We have observed four unambiguous decays of the charmed strange baryon Ξco in the NA32 experiment at CERN. Charge- coupled devices and silicon microstrip detectors were used to reconstruct the decay mode Ξ c o → pK − K ∗ (892) o seen in events produced by the interaction of 230 GeV/c negative poins and kaons on a copper target. We present the first measurement of the lifetime of the Ξco, together with a determination of its mass and production cross section. The resonant components of the Ξco decay are studied. We use our earlier measurement of the mass of the Ξc+ in the determination of the isospin mass splitting of the Ξc states.
Measurement of various decay modes of charmed particlesD 0,D +,D s + andΛ s c
1990
In the CERN NA 32 experiment a high-resolution silicon vertex detector and a purely topological approach have been used to investigate various decays of charmed particles. We observe ∼620 fully reconstructed decays ofD0 in 12 channels and determine the branching ratios. For fourD0 decay modes involving a single (unseen) π0 the small and narrowD*+−D0 mass difference is used to measure their branching ratios. We also observe ∼280 fully reconstructedD+ decays in 10 channels, ∼90Ds+ decays in 11 channels as well as 160Λsc and 18 decay channels ofD+. For theDs+, we measure the branching fractions within a subset of 16 three- and five-prong decay channels. For theΛsc, we determine the branching f…
Inclusive $$\bar K^{0*} (892)$$ andK 0*(892) production on silicon by 200 GeVK − andπ −
1990
The production of the neutralK− (892) resonances by 200 GeVK− andπ− has been studied over the kinematic range 0.0<xf<1.0 andpt2<5.0 GeV2. Longitudinal and transverse momentum distributions are presented. In addition the decay angular distributions inK− fragmentation to\(\bar K^{0*} \) have been investigated.
Production ofD, D * andD s mesons in 200 GeV/c ?? K ? andp-Si interactions
1988
The NA 32 experiment at the CERN SPS has collected 38 million hadronic interactions with incident 200 GeV/c π−,K− andp beam. Using a segmented silicon active target and a telescope of high resolution silicon microstrip counters we have selected fully reconstructedD0→K−π+,D0→K−π+π+π−,D+→K−π+π+,Ds+→K−K+π+π+ and charge conjugate decays. The integrated cross-sections forDo,D+D*+ andDs+ meson production and the dependence of the cross-section on longitudinal and transverse momentum of theD are presented.