Blum, Ira K.
BES
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Search for psi(2S) production in e+ e- annihilations at 4.03-GeV

The BES collaboration Bai, J.Z. ; Bian, J.G. ; Blum, I. ; et al.
Phys.Rev.D 57 (1998) 3854-3859, 1998.
Inspire Record 468969 DOI 10.17182/hepdata.22270

A search is performed for the production of the ψ(2S) in e+e− annihilation at a center-of-mass energy of 4.03 GeV using the BES detector operated at the Beijing Electron Positron Collider (BEPC). The kinematic features of the reconstructed ψ(2S) signal are consistent with its being produced only in association with an energetic photon resulting from initial state radiation (ISR). Limits are placed on ψ(2S) production from the decay of unknown charmonia or metastable hybrids that might be produced in e+e− annihilations at 4.03 GeV. Under the assumption that the observed cross section for ψ(2S) production is due entirely to ISR, the partial width Γee of the ψ(2S) is measured to be 2.07±0.32keV.

1 data table
Table 1

PSI(UNSPEC) is considered as a new 3D2 charmonium state. CHI/C(UNSPEC) is considered as any unknown charmonium state. EXOTIC is considered as a metastable hybrid.


Measurement of the pseudoscalar decay constant, f(D).

The BES collaboration Bai, J.Z. ; Bardon, O. ; Blum, Ira K. ; et al.
SLAC-PUB-7147, 1996.
Inspire Record 421008 DOI 10.17182/hepdata.18760

None

2 data tables
Table 1

No description provided.

Table 2

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
Table 1

No description provided.

Table 2

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