Date

Measurement of alpha-s (M(Z)**2) from hadronic event observables at the Z0 resonance

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Rev.D 51 (1995) 962-984, 1995.
Inspire Record 378545 DOI 10.17182/hepdata.22450

The strong coupling alpha_s(M_Z^2) has been measured using hadronic decays of Z^0 bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O(alpha_s^2), and including resummed analytic formulae based on the next-to-leading logarithm approximation. In this comprehensive analysis we studied event shapes, jet rates, particle correlations, and angular energy flow, and checked the consistency between alpha_s(M_Z^2) values extracted from these different measures. Combining all results we obtain alpha_s(M_Z^2) = 0.1200 \pm 0.0025(exp.) \pm 0.0078(theor.), where the dominant uncertainty is from uncalculated higher order contributions.

16 data tables match query

Final average value of alpha_s. The second (DSYS) error is from the uncertainty on the theoretical part of the calculation.

TAU is 1-THRUST.

RHO is the normalized heavy jet mass MH**2/EVIS**2.

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Inclusive $\pi^0$ Production in 360-{GeV} $p p$ Interactions Using the European Hybrid Spectrometer

The EHS-RCBC collaboration Bailly, J.L. ; Bartl, W. ; Bruyant, F. ; et al.
Z.Phys.C 22 (1984) 119, 1984.
Inspire Record 193697 DOI 10.17182/hepdata.2106

The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσπ°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1−x) dependence is given for differentpT regions.

3 data tables match query

No description provided.

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Axis error includes +- 4/4 contribution.


Neutral $D$ Meson Properties in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Bagnaia, P. ; et al.
Phys.Lett.B 146 (1984) 266-272, 1984.
Inspire Record 202656 DOI 10.17182/hepdata.30495

Based on a sample of 22 four-prong D 0 / D 0 decays produced in hydrogen by 360 GeV/ c π − , we present the following new results: mean lifetime τ = (3.5 −0.9 +1.4 ) x 10 −13 s ; production cross section for x F > 0.0, σ = (10.3 ± 3.5) ωb ; the D → K ± π ± π + π − branching ratio = (7.1 ± 2.5)%.

1 data table match query

No description provided.


Neutral and Charged $D^*$ Production in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 169 (1986) 106-112, 1986.
Inspire Record 227059 DOI 10.17182/hepdata.30268

The first data on the production of D ∗ (2010) are presented as observed in π − -proton interactions at √ s = 27 GeV . It is found that D ∗ (2010) dominates the total charm D-meson production, without a significant non-central component.

4 data tables match query

No description provided.

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Inclusive Properties of d Mesons Produced in 360-GeV pi- p Interactions

The NA27 & LEBC-EHS collaborations Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 161 (1985) 400-406, 1985.
Inspire Record 216596 DOI 10.17182/hepdata.30352

The inclusive cross sections for forward D meson production at s =26 GeV in π − p interactions have been measured to be: σ(π − p → D 0 / D 0 + X ) x F >0 = (10.1±2.2)μ b , σ(π − p → D ±+ X ) x F >0 = (5.7±1.6)μ b . The distribution in x F for all D and for x F >0 has the form d σ/ d x F =107 −37 +39 (1−x F ) 7.5 −1.7 +2.5 +5.4 −3.8 +6.0 (1−x F ) 0.7 −0.7 1.0 μ b , with evidence for leading D production. The p T 2 distribution is exponential with slope parameter [−1.18 −0.16 +0.18 ]( GeV / c) −2 . The data are compared with predictions from first-order quark/gluon fusion calculations.

3 data tables match query

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A Search for F Production in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 156 (1985) 444-450, 1985.
Inspire Record 214934 DOI 10.17182/hepdata.30417

We present the results of a search for charm F mesons in 360 GeV/ c π − p interactions. Several methods have been used; all yield no evidence for the F and are interpreted as 90% confidence level cross section upper limits.

2 data tables match query

D/S+- lifetime was assumed tau = 3.2*10**-13 s.

D/S+- lifetime was assumed tau = 3.2*10**-13 s.


Measurement of the charged multiplicities in b, c and light quark events from Z0 decays.

The SLD collaboration Abe, K. ; Abt, I. ; Akagi, T. ; et al.
Phys.Lett.B 386 (1996) 475-485, 1996.
Inspire Record 422172 DOI 10.17182/hepdata.28349

Average charged multiplicities have been measured separately in $b$, $c$ and light quark ($u,d,s$) events from $Z~0$ decays measured in the SLD experiment. Impact parameters of charged tracks were used to select enriched samples of $b$ and light quark events, and reconstructed charmed mesons were used to select $c$ quark events. We measured the charged multiplicities: $\bar{n}_{uds} = 20.21 \pm 0.10 (\rm{stat.})\pm 0.22(\rm{syst.})$, $\bar{n}_{c} = 21.28 \pm 0.46(\rm{stat.}) ~{+0.41}_{-0.36}(\rm{syst.})$ $\bar{n}_{b} = 23.14 \pm 0.10(\rm{stat.}) ~{+0.38}_{-0.37}(\rm{syst.})$, from which we derived the differences between the total average charged multiplicities of $c$ or $b$ quark events and light quark events: $\Delta \bar{n}_c = 1.07 \pm 0.47(\rm{stat.})~{+0.36}_{-0.30}(\rm{syst.})$ and $\Delta \bar{n}_b = 2.93 \pm 0.14(\rm{stat.})~{+0.30}_{-0.29}(\rm{syst.})$. We compared these measurements with those at lower center-of-mass energies and with perturbative QCD predictions. These combined results are in agreement with the QCD expectations and disfavor the hypothesis of flavor-independent fragmentation.

3 data tables match query

Average charge multiplicity in B-tagged events.

Average charge multiplicity in C-tagged events.

Average charge multiplicity in light quark (uds) events.


Reaction K- p --> Lambda pi0 from 1647-MeV to 1715-MeV

Ponte, R.A. ; Hertzbach, Stanley S. ; Button-Shafer, Janice ; et al.
Phys.Rev.D 12 (1975) 2597-2609, 1975.
Inspire Record 104824 DOI 10.17182/hepdata.24846

This paper contains the results of a study of the reaction K−p→Λπ0 in the center-of-mass-system-energy region of 1647 to 1715 MeV. An energy-dependent partial-wave analysis was performed in this channel. Two allowable solutions were obtained. The first solution in this region contains the D13[t=0.08±0.01, Γ(ER)=44±11 MeV, and ER=1671±3 MeV] partial wave as the only resonant amplitude; the second solution contains both the P11[t=0.16±0.01, Γ(ER)=81±10 MeV, and ER=1671±2 MeV] and the D13[t=0.17±0.01, Γ(ER)=76±5 MeV, and ER=1655±2 MeV] partial wave as resonant.

3 data tables match query

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LAMBDA DECAY-ASYMMETRY PARAMETER TIMES COEFFICIENTS OF ASSOCIATED LEGENDRE POLYNOMIAL EXPANSION.

No description provided.


Multiple Meson Production in Proton-Proton Collisions at 2.85 Bev

Hart, E.L. ; Louttit, R.I. ; Luers, D. ; et al.
Phys.Rev. 126 (1962) 747-756, 1962.
Inspire Record 47769 DOI 10.17182/hepdata.26782

Measurements have been made on 753 four-prong events obtained by exposing the Brookhaven National Laboratory 20-in. liquid hydrogen bubble chamber to 2.85-Bev protons. The partial cross sections observed for multiple meson production reactions are: pp+−(p+p→p+p+π++π−), 2.67±0.13; pn++−, 1.15±0.09; pp+−0, 0.74±0.07; d++−, 0.06±0.02; four or more meson production, 0.04±0.02, all in mb. Production of two mesons appears to occur mainly in peripheral collisions with relatively little momentum transfer. In cases of three-meson production, however, the protons are typically deflected at large angles and are more strongly degraded in energy. The 32, 32 pion-nucleon resonance dominates the interaction; there is some indication that one or both of the T=12, pion-nucleon resonances also play a part. The recently discovered resonance in a T=0, three-pion state appears to be present in the pp+−0 reaction. Results are compared with the predictions of the isobaric nucleon model of Sternheimer and Lindenbaum, and with the statistical model of Cerulus and Hagedorn. The cross section for the reaction π0+p→π++π−+p is derived using an expression from the one-pion exchange model of Drell.

1 data table match query

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Factorial and Cumulant Moments in $e^{+}e^{-}\to$ Hadrons at the Z$^0$ Resonance

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Lett.B 371 (1996) 149-156, 1996.
Inspire Record 415576 DOI 10.17182/hepdata.41682

We present the first experimental study of the ratio of cumulant to factorial moments of the charged-particle multiplicity distribution in high-energy particle interactions, using hadronic Z$^0$ decays collected by the SLD experiment at SLAC. We find that this ratio, as a function of the moment-rank $q$, decreases sharply to a negative minimum at $q=5$, which is followed by quasi-oscillations. These features are insensitive to experimental systematic effects and are in qualitative agreement with expectations from next-to-next-to-leading-order perturbative QCD.

1 data table match query

CONST is the cumulant to factorial moments ratio. See text for definition.