Date

New Results on the Reaction $e^+ e^- \to \mu^+ \mu^-$ at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.D 31 (1985) 2352, 1985.
Inspire Record 212767 DOI 10.17182/hepdata.3935

We have measured the process e+e−→μ+μ− at √s =29 GeV using the High Resolution Spectrometer at SLAC PEP. The forward-backward charge asymmetry is Aμμ=-(4.9±1.5±0.5)% based on 5057 events. A subsample of 3488 μ+μ− events in the angular range ‖cosθ‖<0.55 gives a cross-section ratio of Rμμ=0.990±0.017±0.030. The resulting couplings of the weak neutral current are gaegaμ=0.208±0.064± 0.021 and gvegvμ=0.027 ±0.051±0.089. The QED cutoff parameters are Λ+>170 GeV and Λ−>146 GeV at 95% C.L.

4 data tables match query

Corrected for acceptance and O(alpha**3) QED radiation. Numerical values taken from SUGANO-ANL-HEP-CP-84-90.

Forward-backward asymmetry based on fit to angular distribution. Result is given combined with earlier data from BENDER et al.

No description provided.

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PROPERTIES OF D* PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.
HRS-CP-83-3, 1983.
Inspire Record 192098 DOI 10.17182/hepdata.13343

None

2 data tables match query

D* FRAGMENTATION FUNCTION.

R VALUE IS RADIATIVELY CORRECTED (BUT NOT CROSS SECTION).


Comparison of Charged Particle Multiplicities in Quark and Gluon Jets Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Phys.Lett.B 165 (1985) 449-453, 1985.
Inspire Record 17442 DOI 10.17182/hepdata.30286

The charged particle multiplicities of the quark and gluon jets in the three-fold symmetric e + e − → q q g events at √ s = 29 GeV have been studied using the high resolution spectrometer at PEP. A value of 〈 n 〉 g = 6.7 −2.1 +1.1 ±1.0 for gluon jet s with an energy of 9.7 −2.0 +1.5 GeV is measured. The ratio, 〈 n 〉 g /〈 n 〉 q , is 1.29 −0.41 +0.21 ±0.20, which i s significantly lower than the value of 9 4 naively expected from the ration of the gluon-to-quark color charges.

1 data table match query

Mean jet charged particle interpretations for gluon and quark jets as described above.


Inclusive Charged Particle Production Near the Kinematic Limit in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Kooijman, P. ; Loos, J.S. ; et al.
Phys.Lett.B 164 (1985) 199-202, 1985.
Inspire Record 17255 DOI 10.17182/hepdata.30327

Inclusive production of charged particles has been studied in e + e − annihilation at s s=29 GeV using the high resolution spectrometer at PEP. Differential cross sections are presented in the range of scaled energy 0.1< z <1.0. The data for z <0.5 show the (1− z ) 2 behavior predicted by the dimensional counting rules. Comparisons are made with predictions of the Lund string model and the Webber cluster model.

1 data table match query

Data requested from authors.


Precision Test of {QED} by Direct Comparison of $e^+ e^- \to \gamma \gamma$ and $e^+ e^- \to e^+ e^-$ at 29-{GeV}

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Phys.Lett.B 166 (1986) 468-472, 1986.
Inspire Record 17510 DOI 10.17182/hepdata.30311

The ratio of differential cross sections for the reactions e + e − → γγ and e + e − → e + e − is measured at s = 29 GeV in the central polar angle region, |cos θ | < 0.55, and compared to the same ratio calculated by QED to order α 3 . The ratio of these ratios, integrated over this angular region, is 1.007±0.009±0.008, demonstrating excellent agreement between theory and experiment. The 95% confidence limits on the QED cut-off parameters for the γγ final state are Λ + > 59 GeV and Λ - > 59 GeV.

1 data table match query

No description provided.


Comparison of Light Quark and Charm Quark Fragmentation

Kesten, P. ; Akerlof, C. ; Bonvicini, G. ; et al.
Phys.Lett.B 161 (1985) 412-416, 1985.
Inspire Record 17116 DOI 10.17182/hepdata.30349

Separate samples of charm quark and light quark (u, d, s) jets have been isolated in an experiment studying e + e − annihilations at s = 29 GeV . The results come from data corresponding to an integrated luminosity of 111 pb −1 collected by the High Resolution Spectrometer. Differences were observed in charged multiplicities, momentum distributions, and rapidity of the size expected from the different fragmentation functions and leading particle decay properties of the two samples.

3 data tables match query

Charm Quark Jet Trigger. Characteristics of Jet Opposite the Trigger Jet.

Light Quark Jet Trigger. Characteristics of Jet Opposite the Trigger Jet.

No description provided.


Rapidity Dependence of the Charged Particle Multiplicity Distributions in e+ e- Annihilation at 29-GeV

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Phys.Lett.B 168 (1986) 299-304, 1986.
Inspire Record 17794 DOI 10.17182/hepdata.30277

The charged particle multiplicity distribution for e + e − annihilations at s = 29 GeV has been measured using the High Resolution Spectrometer at PEP. The multiplicity distribution, expressed as a function of the mean, shows KNO scaling when compared to e + e − data at other energies. Multiplicity distributions for particles selected in different central rapidity spans are presented. All of these are well presented by the Negative binomial distribution. As the rapidity span is narrowed, the distributions become broader and approach a constant value of the parameter k .

12 data tables match query

KNO charged multiplicity distributions for the Inclusive Data Sample. The numerical values are calculated from the multiplicity distributions given in Derrick et al., PR D34,3304.

Folded rapidity distribution measured along the thrust axis of the event. Errors are dominated by systematics. All charged particles are assigned the pion mass.

KNO charged multiplicity distribution for the Two Jet Data Sample. The numerical values are calculated from the multiplicity distributions given in Derrick et al., PR D34,3304.

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Neutral $K^*$ (890) and $\rho^0$ Meson Production in $e^+ e^-$ Annihilation at the $\sqrt{s}=29$-{GeV}

Derrick, M. ; Kooijman, P. ; Loos, J.S. ; et al.
Phys.Lett.B 158 (1985) 519-524, 1985.
Inspire Record 16663 DOI 10.17182/hepdata.30388

The production of neutral K ∗ (890) and ρ 0 mesons was studied in e + e − annihilation at s =29 GeV using the High Resolution Spectrometer at PEP. Differential cross sections are presented as a function of the scaled energy variable z and compared to π 0 and K 0 production. The measured multiplicities are 0.84±0.08 ϱ 0 mesons and 0.57±0.09 K ∗0 (890) mesons per event for a meson momentum greater than 725 MeV/ c . The ratios of vector meson to pseudoscalar meson production for (u,d), s and c quark are compared to predictions of the Lund model.

3 data tables match query

Data requested from authors.

No description provided.

No description provided.


$\Lambda$ Production in $e^+ e^-$ Annihilations at 29-{GeV}: A Comparison With Lund Model Predictions

Baringer, Philip S. ; Abachi, S. ; Beltrami, I. ; et al.
Phys.Rev.Lett. 56 (1986) 1346, 1986.
Inspire Record 17781 DOI 10.17182/hepdata.20257

This paper presents measurements of the inclusive production cross sections of Λ baryons in e+e− annihilations at s=29 GeV. The data sample corresponds to an integrated luminosity of 256 pb−1 collected with the High-Resolution Spectrometer at the SLAC storage ring PEP. Comparisons are made to the predictions of the Lund model. The data are well described with use of a strange-diquark suppression parameter, (usud)(sd), of 0.89 ± 0.10−0.16+0.56, and the measured Λc→Λ+X branching ratio of (23 ± 10)%.

3 data tables match query

No description provided.

Rapidity relative to thrust axis.

Corrected for unobserved moment regions.


Production of $\phi$ and F (1970) $\to \phi \pi$ in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 54 (1985) 2568, 1985.
Inspire Record 213242 DOI 10.17182/hepdata.20340

Data from the high-resolution spectrometer at PEP have been used to study the inclusive production of φ mesons and F± mesons decaying into φπ±. Fragmentation functions and cross sections are presented and compared to existing data. The total φ cross section at 29 GeV is 40±6 pb. The observed F signal in the region z>0.4, given the assumption that R(F)[R(F)+R(D)]=0.15, corresponds to an F→φπ branching ratio of (3.3±1.1)%. The measured F mass is 1963±3±3 MeV/c2.

5 data tables match query

No description provided.

No description provided.

WITH THE FOLLOWING ANGLE CUTS ON THE DECAY REGIONS. PHI DECAY - ABS(COS(THETA)) >0.5.

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