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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.


First observation of the reaction gamma gamma ---> pi (2) ---> pi0 pi0 pi0

The Crystal Ball collaboration Antreasyan, D. ; Bartels, H.W. ; Besset, D. ; et al.
Z.Phys.C 48 (1990) 561-568, 1990.
Inspire Record 296523 DOI 10.17182/hepdata.15136

The Crystal Ball detector has been used at the DORIS II storage ring at DESY to study the reactionγγ→π0π0π0 in theπ0π0π0 invariant mass range from 850 MeV/c2 to 2600 MeV/c2. An enhancement around 1750 MeV/c2 is attributed to theπ2(1670) resonance. The observedπ0π0 invariant mass distribution and theπ0 angular distributions are consistent with those expected for the decay chainπ2→π0f2(1270)→π0π0π0. From our measurements we find the following resonance parameters: two photon partial width\(\Gamma _{\pi _2 }^{\gamma \gamma }= (1.41 \pm 0.23 \pm 0.28)keV\), massM(π2)=(1742±31±49)MeV/c2. and total width\(\Gamma _{\pi _2 }^{tot}= (236 \pm 49 \pm 36)MeV\).

2 data tables
Table 1

Data read from graph.

Table 2

Cross section times branching ratio to 3pi0 assuming the decay chain pi2 --> pi0f2 --> 3pi0.


A Measurement of $\pi^0 \pi^0$ Production in Two Photon Collisions

The Crystal Ball collaboration Marsiske, H. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Phys.Rev.D 41 (1990) 3324, 1990.
Inspire Record 294492 DOI 10.17182/hepdata.22923

The reaction e+e−→e+e−π0π0 has been analyzed using 97 pb−1 of data taken with the Crystal Ball detector at the DESY e−e+ storage ring DORIS II at beam energies around 5.3 GeV. For the first time we have measured the cross section for γγ→π0π0 for π0π0 mvariant masses ranging from threshold to about 2 GeV. We measure an approximately flat cross section of about 10 nb for W=mπ0π0<0.8 GeV, which is below 0.6 GeV, in good agreement with a theoretical prediction based on an unitarized Born-term model. At higher invariant masses we observe formation of the f2(1270) resonance and a hint of the f0(975). We deduce the following two-photon widths: Γγγ(f2(1270))=3.19±0.16±0.280.29 keV and Γγγ(f0(975))<0.53 keV at 90% C.L. The decay-angular distributions show the π0π0 system to be dominantly spin 0 for W<0.7 GeV and spin 2, helicity 2 in the f2(1270) region, with helicity 0 contributing at most 22% (90% C.L.).

2 data tables
Table 1

Statistical errors only.

Table 2

Statistical errors only.


rivet Analysis
Hadron Production in $e^+ e^-$ Annihilation From $\sqrt{s}=5$-{GeV} to 7.4-{GeV}

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
SLAC-PUB-5160, 1990.
Inspire Record 294419 DOI 10.17182/hepdata.18758

None

4 data tables
Table 1

Data from Run 1. There is an additional overall systematic uncertainty of 5.2 pct.

Table 2

Data from Run 2. There is an additional overall systematic uncertainty of 5.2 pct.

Table 3

Average R value.

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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.


rivet Analysis
Measurements of Total Hadronic and Inclusive $D^*$ Cross-sections in $e^+ e^-$ Annihilations Between 3.87-{GeV} and 4.5-{GeV}

Osterheld, A. ; Hofstadter, R. ; Horisberger, R. ; et al.
SLAC-PUB-4160, 1986.
Inspire Record 238081 DOI 10.17182/hepdata.18759

None

2 data tables
Table 1

R measurement.

Table 2

D* cross sections.


Formation of Delta (980) and A2 (1320) in Photon-photon Collisions

The Crystal Ball collaboration Antreasyan, D. ; Aschman, D. ; Besset, D. ; et al.
Phys.Rev.D 33 (1986) 1847, 1986.
Inspire Record 217547 DOI 10.17182/hepdata.23518

The reaction γγ→π0η has been investigated with the Crystal Ball detector at the DESY storage ring DORIS II. Formation of δ(980) and A2(1320) has been observed with γγ partial widths Γγγ(A2)=1.14±0.20±0.2 6 keV and Γγγ(δ)B(δ→πη)=0.19±0.07 −0.07+0.10 keV.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
Phys.Lett.B 110 (1982) 82-86, 1982.
Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables
Table 1

Data read from graph. Systematic error on M is of order of 2% or less.

Table 2

Data read from graph.

Table 3

No description provided.


Measurement of Inclusive $\eta$ Production in $e^+ e^-$ Interactions Near Charm Threshold

Partridge, Richard ; Peck, C. ; Porter, F. ; et al.
Phys.Rev.Lett. 47 (1981) 760, 1981.
Inspire Record 165255 DOI 10.17182/hepdata.3280

We have measured the inclusive cross section for η production in e+e− interactions near charm threshold using the Crystal Ball detector. No pronounced structure in the energy dependence is observed. By comparing cross sections above and below charm threshold we obtain the limits (90% confidence limit): R(e+e−→FF¯X)RB(F→ηx)<0.15−0.32 (for Ec.m. from 4.0 to 4.5 GeV), RB(D→ηx)<0.13. Our results are inconsistent with a previous report of a large energy dependence of the η cross section ascribed to the crossing of the FF* and F*F* production thresholds.

7 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////DECAY PI0 --> 2GAMMA//RES-DEF(RES=ETA,BACK=CORRECTED,DEF=340 < M( 2GAMMA ) < 800 MEV)//DECAY-BR(BRN=ETA --> 2GAMMA,BR=38 PCT)).

Table 2

THE 4.028 GEV DATA ARE NOT INCLUDED IN THE 4.005-4.082 GEV BIN. Axis error includes +- 0.0/0.0 contribution (?////DECAY PI0 --> 2GAMMA//RES-DEF(RES=ETA,BACK=CORRECTED,DEF=340 < M( 2GAMMA ) < 800 MEV)//DECAY-BR(BRN=ETA --> 2GAMMA,BR=38 PCT)).

Table 3

AT FIXED ENERGIES.

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Inclusive Production of High-Energy Neutral Pions from Pion-Proton Collisions at 14-GeV/c

O'Neill, L.H. ; Ford, R.L. ; Crawford, J.F. ; et al.
Phys.Rev.D 14 (1976) 2878, 1976.
Inspire Record 109511 DOI 10.17182/hepdata.21929

Measurements of the differential cross section for the inclusive production of high-energy π0's are reported for the reactions π±p→π0X at a laboratory momentum of 14 GeV/c. The kinematic range covered, in terms of the Feynman scaling variable x and the transverse momentum P⊥, is 0.25≤x≤1.0 and 0≤P⊥≤0.7 GeV/c. Two spectrometers, both employing large NaI(Tl) crystals, are used to detect the π0's and to identify them with a mass resolution of 17 MeV (full width at half maximum). The results are in accord with the hypothesis of limiting fragmentation, which regards the measured reactions, in the kinematic range covered, as examples of disfavored fragmentation.

2 data tables
Table 1

No description provided.

Table 2

No description provided.