Date

First measurement of the ratio B(t ---> W b) / B(t ---> W q) and associated limit on the CKM element |V(tb)|

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 86 (2001) 3233-3238, 2001.
Inspire Record 538411 DOI 10.17182/hepdata.42945

We present the first measurement of the ratio of branching fraction R= B(t-->wb)/B(t-->Wq) from ppbar collisions at sqrt(s)=1.8 TeV. The data set corresponds to 109 pb-1 of data recorded by the Collider Detector at Fermilab during the 1992-1995 Tevatron run. We measure R=0.94+.31-.24 (stat+syst) or R>0.61 (0.56) at 90 (95) %C.L., in agreement with the standard model predictions. This measurement yields a limit of the Cabibbo-Kobayashi-Maskawa quark mixing matrix element Vtb under the assumption of three generation unitarity.

2 data tables

Charge conjugated states are understood.

No description provided.


Observation of a narrow state decaying into Xi(c)+ pi-

The CLEO collaboration Avery, P. ; Freyberger, A. ; Lingel, K. ; et al.
Phys.Rev.Lett. 75 (1995) 4364-4368, 1995.
Inspire Record 397770 DOI 10.17182/hepdata.47270

Using data recorded by the CLEO-II detector at CESR, we report the first observation of a narrow state decaying into $\Xi_c~+\pi~-$. The state has mass difference $M(\Xi_c~+\pi~-)-M(\Xi_c~+)$ of $178.2\pm0.5\pm1.0$ $\rm{MeV/c~2}$, and a width of $<5.5$ $\rm{MeV/c~2}$ (90\% confidence level limit). The most likely explanation of this new state is that it is the $J=\32$ spin excitation of the $\Xi_c~0$ charmed baryon.

1 data table

No description provided.


Study of Charged Hadronic Four-Body Decays of the $D^0$ Meson

The E687 collaboration Frabetti, P.L. ; Cheung, H.W.K. ; Cumalat, John P. ; et al.
Phys.Lett.B 354 (1995) 486-493, 1995.
Inspire Record 395966 DOI 10.17182/hepdata.21354

Charged hadronic four-body decays of D 0 mesons have been studied in the E687 photoproduction experiment at Fermilab. Branching ratios relative to the D 0 → K − π + π + π − decay mode for the Cabibbo-suppressed decays D 0 → π − π + π − π + , D 0 → K − K + π − π + have been measured and the first evidence of the D 0 → K − K + K − π + decay mode is reported. An analysis of the D 0 → K − K + π − π + resonance structure is also presented.

3 data tables

No description provided.

No description provided.

No description provided.


A Direct measurement of the pseudoscalar decay constant, f(D(s))

The BES collaboration Bai, J.Z. ; Bardon, O. ; Blum, Ira K. ; et al.
Phys.Rev.Lett. 74 (1995) 4599-4602, 1995.
Inspire Record 382314 DOI 10.17182/hepdata.50375

The Beijing Spectrometer (BES) experiment has observed purely leptonic decays of the Ds meson in the reaction e+e−→Ds+Ds− at a c.m. energy of 4.03 GeV. Three events are observed in which one Ds decays hadronically to φπ, K¯*0K, or K¯0K, and the other decays leptonically to μνμ or τντ. With the assumption of μ−τ universality, values of the branching fraction, B(Ds→μνμ)=(1.5−0.6−0.2+1.3+0.3)%, and the Ds pseudoscalar decay constant, fDs=(4.3−1.3−0.4+1.5+0.4)×102 MeV, are obtained.

2 data tables

No description provided.

In this table CONST is the pseudoscalar decay constant, f_[D/S].


Measurement of two photon production of the chi(c2)

The CLEO collaboration Shelkov, V. ; Dominick, J. ; Sanghera, S. ; et al.
Phys.Rev.D 50 (1994) 4265-4271, 1994.
Inspire Record 359316 DOI 10.17182/hepdata.52343

The CLEO II detector is used to search for the production of χc2 states in two-photon interactions. We use the signature χc2→γJ/ψ→γl+l− with l=e,μ. Using 1.49 fb−1 of data taken with beam energies near 5.29 GeV, the two-photon width of the χc2 is determined to be Γ(χc2→γγ)=1.08±0.30(stat)±0.26(syst) keV, in agreement with predictions from perturbative QCD.

2 data tables

Results below were obtained usign J/psi from-factors in the two photon propogators, and assumes that only transversely polarized photons are significant inthe production of the CHI/C2(1P) state.

No description provided.