Cho, Kihyeon
E+ E- Scattering
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rivet Analysis
Observation of a near-threshold enhancement in the $e^+e^- \to \Lambda_c^+ \Lambda_c^-$ cross section using initial-state radiation

The Belle collaboration Pakhlova, G. ; Adachi, I. ; Aihara, H. ; et al.
Phys.Rev.Lett. 101 (2008) 172001, 2008.
Inspire Record 791660 DOI 10.17182/hepdata.21861

We report a measurement of the exclusive \$e^+e^- \to \Lambda_c^+ \Lambda_c^-$ cross section as a function of center-of-mass energy near the $\Lambda_c^+ \Lambda_c^-$ threshold. A clear peak with a significance of $8.8\sigma$ is observed in the $\Lambda_c^+ \Lambda_c^-$ invariant mass distribution just above threshold. With an assumption of a resonance origin for the observed peak, a mass and width of $M=(4634^{+8}_{-7} \mathrm{(stat.)} ^{+5}_{-8} \mathrm{(sys.)})\mevc$ and $\Gamma_{\mathrm{tot}}=(92^{+40}_{-24} \mathrm{(stat.)}^{+10}_{-21} \mathrm{(sys.)})\mev$ are determined. The analysis is based on a study of events with initial-state-radiation photons in a data sample collected with the Belle detector at the $\Upsilon(4S)$ resonance and nearby continuum with an integrated luminosity of 695 $\mathrm{fb}^{-1}$ at the KEKB asymmetric-energy $e^+e^_$ collider.

1 data table
Table 1

Cross section for the exclusive process E+ E- --> LAMBDA/C+ LAMBDA/CBAR-.


rivet Analysis
Observation of $\psi(4415)\to D \bar D{}^{*}_2(2460)$ decay using initial-state radiation

The Belle collaboration Pakhlova, G. ; Adachi, I. ; Aihara, H. ; et al.
Phys.Rev.Lett. 100 (2008) 062001, 2008.
Inspire Record 759073 DOI 10.17182/hepdata.21846

We report the first observation of the $\psi(4415)$ resonance in the reaction $\e^+e^-\to D^0 D^-\pi^+$ and a measurement of its cross section in the center-of-mass energy range $4.0\mathrm{GeV}$ to $5.0\mathrm{GeV}$ with initial state radiation. From a study of resonant structure in $\psi(4415)$ decay we conclude that the $\psi(4415)\to D^0 D^-\pi^+$ decay is dominated by $\psi(4415)\to D \bar D{}^{*}_2(2460)$. We obtain $\mathcal{B}(\psi(4415)\to D^0 D^-\pi^+_{\mathrm {non-resonant}})/\mathcal{B}(\psi(4415)\to D \bar D{}^{*}_2(2460)\to D^0 D^-\pi^+)<0.22$ at 90% C.L. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 673 $\mathrm{fb}^{-1}$.

1 data table
Table 1

The measured cross section for E+ E- --> D0 D- PI+.


rivet Analysis
Observation of Two Resonant Structures in e+e- to pi+ pi- psi(2S) via Initial State Radiation at Belle

The Belle collaboration Wang, X.L. ; Yuan, C.Z. ; Shen, C.P. ; et al.
Phys.Rev.Lett. 99 (2007) 142002, 2007.
Inspire Record 756643 DOI 10.17182/hepdata.51373

The cross section for e+e- to pi+ pi- psi(2S) between threshold and \sqrt{s}=5.5 GeV is measured using 673 fb^{-1} of data on and off the \Upsilon(4S) resonance collected with the Belle detector at KEKB. Two resonant structures are observed in the pi+ pi- psi(2S) invariant mass distribution, one at 4361\pm 9\pm 9 MeV/c2 with a width of 74\pm 15\pm 10 MeV/c2, and another at 4664\pm 11\pm 5 MeV/c2 with a width of 48\pm 15\pm 3 MeV/c2, if the mass spectrum is parameterized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states.

1 data table
Table 1

Measured cross section.


rivet Analysis
Measurement of $e^+e^- \to \pi^+\pi^-J/\psi$ Cross Section via Initial State Radiation at Belle

The Belle collaboration Yuan, C.Z. ; Shen, C.P. ; Wang, P. ; et al.
Phys.Rev.Lett. 99 (2007) 182004, 2007.
Inspire Record 756012 DOI 10.17182/hepdata.50926

The cross section for e^+e^- to pi^+pi^-J/psi between 3.8 and 5.5 GeV/c^2 is measured using a 548 fb^{-1} data sample collected on or near the Upsilon(4S) resonance with the Belle detector at KEKB. A peak near 4.25 GeV/c^2, corresponding to the so called Y(4260), is observed. In addition, there is another cluster of events at around 4.05 GeV/c^2. A fit using two interfering Breit-Wigner shapes describes the data better than one that uses only the Y(4260), especially for the lower mass side of the 4.25 GeV enhancement.

1 data table
Table 1

Measured cross section. Statistical errors only.


rivet Analysis
Measurements of the meson photon transition form factors of light pseudoscalar mesons at large momentum transfer.

The CLEO collaboration Gronberg, J. ; Hill, T.S. ; Kutschke, Robert K. ; et al.
Phys.Rev.D 57 (1998) 33-54, 1998.
Inspire Record 446031 DOI 10.17182/hepdata.47203

Using the CLEO~II detector, we have measured the differential cross sections for exclusive two-photon production of light pseudoscalar mesons $\pi^0$, $\eta$, and $\eta^{\prime}$. From our measurements we have obtained the form factors associated with the electromagnetic transitions $\gamma^*\gamma$ $\to$ meson. We have measured these form factors in the momentum transfer ranges from 1.5 to 9, 20, and 30 GeV$^2$ for $\pi^0$, $\eta$, and $\eta^{\prime}$, respectively, and have made comparisons to various theoretical predictions.

10 data tables
Table 1

The results of PI0 --> GAMMA GAMMA analysis assuming Br(PI0-->2GAMMA)=0.99.

Table 2

The results of ETA --> GAMMA GAMMA analysis assuming Br(ETA-->2GAMMA)=0.39.

Table 3

The results of ETA --> 3PI0 analysis assuming Br(ETA-->3PI0)*Br(PI0-->2GAM MA)**3 = 0.31.

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rivet Analysis
Measurement of the total cross section for e+ e- --> hadrons at s**(1/2) = 10.52-GeV.

The CLEO collaboration Ammar, R. ; Baringer, Philip S. ; Bean, A. ; et al.
Phys.Rev.D 57 (1998) 1350-1358, 1998.
Inspire Record 445351 DOI 10.17182/hepdata.47132

Using the CLEO detector at the Cornell Electron Storage Ring, we have made a measurement of R=sigma(e+e- ->hadrons)/sigma(e+e- ->mu+mu-) =3.56+/-0.01+/-0.07 at ECM=10.52 GeV. This implies a value for the strong coupling constant of alpha_s(10.52 GeV)=0.20+/-0.01+/-0.06, or alpha_s(M_Z)=0.13+/-0.005+/-0.03.

2 data tables
Table 1

Corrected for background and radiactive effects.

Table 2

Value of ALPHAS, the strong coupling constant, from the measurement of R. CT,= ALPHAS also given evolved to the Z0 mass.


rivet Analysis
First observation of inclusive B decays to the charmed strange baryons Xi/c0 and Xi/c+.

The CLEO collaboration Barish, B. ; Chadha, M. ; Chan, S. ; et al.
Phys.Rev.Lett. 79 (1997) 3599-3603, 1997.
Inspire Record 442910 DOI 10.17182/hepdata.47081

Using data collected in the region of the Upsilon(4S) resonance with the CLEO II detector operating at the Cornell Electron Storage Ring CESR, we present the first observation of B mesons decaying into the charmed strange baryons Xi_c0 and Xi_c+. We find 79 +/- 27 Xi_c0 and 125 +/- 28 Xi_c+ candidates from B decays, leading to product branching fractions of BR(Bbar -> Xi_c0 X)BR(Xi_c0 -> Xi- pi+) = (0.144 +/- 0.048 +/- 0.021) x 10~-3 and BR(Bbar -> Xi_c+ X)BR(Xi_c+ -> Xi- pi+ pi+) = (0.453 +/- 0.096 +0.085-0.065) x 10~-3.

2 data tables
Table 1

Charge conjugated states are included. P(P=4,C=MAX) equals sqrt(Ebeam**2 - m(XI/C)**2). The kinematic limit is : (P(XI/C) / P(P=4,C=MAX)) < 0.5.

Table 2

Charge conjugated states are included. P(P=4,C=MAX) equals sqrt(Ebeam**2 - m(XI/C)**2). The kinematic limit is : (P(XI/C) / P(P=4,C=MAX)) < 0.5.


rivet Analysis
Lambda Antilambda production in two-photon interactions at CLEO.

The CLEO collaboration Anderson, S. ; Kubota, Y. ; Lattery, M. ; et al.
Phys.Rev.D 56 (1997) R2485-R2489, 1997.
Inspire Record 439745 DOI 10.17182/hepdata.47140

Using the CLEO detector at the Cornell $e~+e~-$ storage ring, CESR, we study the two-photon production of $\Lambda \overline{\Lambda}$, making the first observation of $\gamma \gamma \to \Lambda \overline{\Lambda}$. We present the cross-section for $ \gamma \gamma \to \Lambda \overline{\Lambda}$ as a function of the $\gamma \gamma$ center of mass energy and compare it to that predicted by the quark-diquark model.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Study of gluon versus quark fragmentation in Upsilon --> g g gamma and e+ e- --> q anti-q gamma events at s**(1/2) = 10-GeV.

The CLEO collaboration Alam, M.S. ; Athar, S.B. ; Ling, Z. ; et al.
Phys.Rev.D 56 (1997) 17-22, 1997.
Inspire Record 439530 DOI 10.17182/hepdata.47233

Using data collected with the CLEO II detector at the Cornell Electron Storage Ring, we determine the ratio R(chrg) for the mean charged multiplicity observed in Upsilon(1S)->gggamma events, to the mean charged multiplicity observed in e+e- -> qqbar gamma events. We find R(chrg)=1.04+/-0.02+/-0.05 for jet-jet masses less than 7 GeV.

1 data table
Table 1

No description provided.


Measurement of the direct photon spectrum in Upsilon(1S) decays.

The CLEO collaboration Nemati, B. ; Richichi, S.J. ; Ross, W.R. ; et al.
Phys.Rev.D 55 (1997) 5273-5281, 1997.
Inspire Record 425927 DOI 10.17182/hepdata.52340

Using data taken with the CLEO II detector at the Cornell Electron Storage Ring, we have determined the ratio of branching fractions: $R_{\gamma} \equiv \Gamma(\Upsilon(1S) \rightarrow \gamma gg)/\Gamma(\Upsilon(1S) \rightarrow ggg) = (2.75 \pm 0.04(stat.) \pm 0.15(syst.))%$. From this ratio, we have determined the QCD scale parameter $\Lambda_{\overline{MS}}$ (defined in the modified minimal subtraction scheme) to be $\Lambda_{\overline{MS}}= 233 \pm 11 \pm 59$ MeV, from which we determine a value for the strong coupling constant $\alpha_{s}(M_{\Upsilon(1S)}) = 0.163 \pm 0.002 \pm 0.014$, or $\alpha_{s}(M_{Z}) = 0.110 \pm 0.001 \pm 0.007$.

1 data table
Table 1

The ALPHAS at MZ is extrapolation from M(UPSI).