Robertson, W.J
Upsilon
[5.0, 10.0]
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rivet Analysis
Inclusive Lambda/c production in e+ e- annihilations at s**(1/2) = 10.54-GeV and in Upsilon(4S) decays.

The BaBar collaboration Aubert, Bernard ; Bona, M. ; Boutigny, D. ; et al.
Phys.Rev.D 75 (2007) 012003, 2007.
Inspire Record 725377 DOI 10.17182/hepdata.22089

We present measurements of the total production rates and momentum distributions of the charmed baryon $\Lambda_c^+$ in $e^+e^- \to$ hadrons at a center-of-mass energy of 10.54 GeV and in $\Upsilon(4S)$ decays. In hadronic events at 10.54 GeV, charmed hadrons are almost exclusively leading particles in $e^+e^- \to c\bar{c}$ events, allowing direct studies of $c$-quark fragmentation. We measure a momentum distribution for $\Lambda_c^+$ baryons that differs significantly from those measured previously for charmed mesons. Comparing with a number of models, we find none that can describe the distribution completely. We measure an average scaled momentum of $\left< x_p \right> = 0.574\pm$0.009 and a total rate of $N_{\Lambda c}^{q\bar{q}} = 0.057\pm$0.002(exp.)$\pm$0.015(BF) $\Lambda_c^+$ per hadronic event, where the experimental error is much smaller than that due to the branching fraction into the reconstructed decay mode, $pK^-\pi^+$. In $\Upsilon (4S)$ decays we measure a total rate of $N_{\Lambda c}^{\Upsilon} = 0.091\pm$0.006(exp.)$\pm$0.024(BF) per $\Upsilon(4S)$ decay, and find a much softer momentum distribution than expected from B decays into a $\Lambda_c^+$ plus an antinucleon and one to three pions.

4 data tables
Table 1

LAMBDA/C+ differential production rate per hadronic event for the continuum at cm energy 10.54 GeV.

Table 2

The integrated number of LAMBDA/C+'s per hadronic event for the continuum at cm energy 10.54 GeV.

Table 3

LAMBDA/C+ differential production rate per UPSILON(4S) decay at cm energy 10.58 GeV.

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Production of upsilon(1S) mesons from chi(b) decays in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 84 (2000) 2094-2099, 2000.
Inspire Record 508395 DOI 10.17182/hepdata.50106

We have reconstructed the radiative decays $\chi_{b}(1P) \to \Upsilon(1S) \gamma $ and $\chi_{b}(2P) \to \Upsilon(1S) \gamma $ in $p \bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV, and measured the fraction of $\Upsilon(1S)$ mesons that originate from these decays. For $\Upsilon(1S)$ mesons with $p^{\Upsilon}_{T}>8.0$ GeV/$c$, the fractions that come from $\chi_{b}(1P)$ and $\chi_{b}(2P)$ decays are $(27.1\pm6.9(stat)\pm4.4(sys))%$ and $(10.5\pm4.4(stat)\pm1.4(sys))%$, respectively. We have derived the fraction of directly produced $\Upsilon(1S)$ mesons to be $(50.9\pm8.2(stat)\pm9.0(sys))%$.

1 data table
Table 1

No description provided.


Measurement of the decay of the Upsilon (1S) and Upsilon (2S) resonances to muon pairs

The Crystal Ball collaboration Kobel, M. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Z.Phys.C 53 (1992) 193-206, 1992.
Inspire Record 306832 DOI 10.17182/hepdata.14771

Using the Crystal Ball detector at thee+e− storage ring DORIS II, we have measured the branching fraction to muon pairsBμμ of the Υ(

2 data tables
Table 1

Corrected cross section. Statistical and point to point systematic errors combined. Additional systematic error given above. The storage ring SQRT(S) has a 7.9 +- 0.2 MeV energy spread around the values given.

Table 2

Corrected cross section. Statistical and point to point systematic errors combined. Additional systematic error given above.The storage ring SQRT(S) has a 8.2 +- 0.3 MeV energy spread around the values given.


rivet Analysis
Determination of $\gamma (e e$) of the $\Upsilon$ (1s) and $\Upsilon$ (2s) Resonances and Measurement of R at $W=9$.39-{GeV}

The Crystal Ball collaboration Jakubowski, Z. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Z.Phys.C 40 (1988) 49, 1988.
Inspire Record 261078 DOI 10.17182/hepdata.15560

Using the Crystal Ball detector operating at the DORIS II storage ring we have measured the leptonic partial widthsГeeof the Υ(1S) and Υ(2S) reson

1 data table
Table 1

No description provided.