Initial Measurements of Z Boson Resonance Parameters in e+ e- Annihilation

Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.
Phys.Rev.Lett. 63 (1989) 724, 1989.
Inspire Record 280007 DOI 10.17182/hepdata.20034

We have measured the mass of the Z boson to be 91.11±0.23 GeV/c2, and its width to be 1.61−0.43+0.60 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.62±0.23 GeV, corresponding to 3.8±1.4 neutrino species.

1 data table match query

Data now superceded.


CHARM PHOTOPRODUCTION CROSS-SECTION AT 20-GeV

Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.Lett. 51 (1983) 156, 1983.
Inspire Record 189662 DOI 10.17182/hepdata.20508

Forty-seven charm events have been observed in an exposure of the SLAC Hybrid Facility bubble chamber to a 20-GeV backward-scattered laser beam. Thirty-seven events survive all the necessary cuts imposed. Based on this number the total charm cross section is calculated to be 63−28+33 nb.

1 data table match query

No description provided.


A Comparison of K+- n Charge Exchange Reactions at 8.5-GeV/c and 13-GeV/c

Gilchriese, M.G.D. ; Dunwoodie, W.M. ; Fieguth, T.H. ; et al.
Phys.Rev.Lett. 40 (1978) 6, 1978.
Inspire Record 120363 DOI 10.17182/hepdata.20886

The cross sections for the line-reversed reaction pairs K+n→K0p and K−p→K¯0n, and K+p→K0Δ++ and K−n→K¯0Δ− have been determined with high statistics and good relative normalization at 8.36 and 12.8 GeV/c in a spectrometer experiment at Stanford Linear Accelerator Center. The cross sections for the K+-induced reactions are larger than for the K−, contrary to the expectations of weakly-exchange-degenerate Regge-pole models. The ratio of the reaction cross sections is about the same as at lower energies and shows little change with momentum transfer.

4 data tables match query

Axis error includes +- 11/11 contribution.

Axis error includes +- 11/11 contribution.

Axis error includes +- 11/11 contribution.

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Inclusive Photoproduction of Neutral Strange Particles at 20-{GeV}

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.D 29 (1984) 1877, 1984.
Inspire Record 190724 DOI 10.17182/hepdata.23774

We have studied inclusive production of KS0, Λ, and Λ¯ particles in 20-GeV γp interactions and have found features similar to those observed in both hadronic and leptonic interactions. The production cross sections, charged-particle multiplicities, and average Λ polarization are reported. Inclusive distributions of x and pT are shown and discussed in terms of quark fragmentation models. Production cross sections for K*(890) and Σ*(1385) are also reported.

9 data tables match query

No description provided.

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Measurement of CP violating asymmetries in B0 decays to CP eigenstates

The BaBar collaboration Aubert, Bernard ; Boutigny, D. ; De Bonis, I. ; et al.
Phys.Rev.Lett. 86 (2001) 2515-2522, 2001.
Inspire Record 553002 DOI 10.17182/hepdata.50471

We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23 million Upsilon(4S)-->B-anti-B decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events where one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta=0.34 +/- 0.20 (stat) +/- 0.05 (syst).

1 data table match query

Standard Model predicts the time-dependent rate asymmetry as follows: A(t) = (B0(t)-BBAR0(t))/(B0(t)+BBAR0(t)) = SIN(2*BETA)*SIN(Delta(M)*t), where Delta(M) is the mass difference between the two B0 mass eigenstates. The total systematic error equals +0.50 -0.46.


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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A low-mass dark matter search using ionization signals in XENON100

The XENON collaboration Aprile, E. ; Aalbers, J. ; Agostini, F. ; et al.
Phys.Rev.D 94 (2016) 092001, 2016.
Inspire Record 1463250 DOI 10.17182/hepdata.78548

We perform a low-mass dark matter search using an exposure of 30\,kg$\times$yr with the XENON100 detector. By dropping the requirement of a scintillation signal and using only the ionization signal to determine the interaction energy, we lowered the energy threshold for detection to 0.7\,keV for nuclear recoils. No dark matter detection can be claimed because a complete background model cannot be constructed without a primary scintillation signal. Instead, we compute an upper limit on the WIMP-nucleon scattering cross section under the assumption that every event passing our selection criteria could be a signal event. Using an energy interval from 0.7\,keV to 9.1\,keV, we derive a limit on the spin-independent WIMP-nucleon cross section that excludes WIMPs with a mass of 6\,GeV/$c^2$ above $1.4 \times 10^{-41}$\,cm$^2$ at 90\% confidence level.

1 data table match query

WIMP exclusion limit on the spin-independent WIMP-nucleon scattering cross section at 90% confidence level.


Study of Charm Fragmentation into $D^{*\pm}$ Mesons in Deep-Inelastic Scattering at HERA

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Andreev, V. ; et al.
Eur.Phys.J.C 59 (2009) 589-606, 2009.
Inspire Record 792603 DOI 10.17182/hepdata.45316

The process of charm quark fragmentation is studied using $D^{*\pm}$ meson production in deep-inelastic scattering as measured by the H1 detector at HERA. Two different regions of phase space are investigated defined by the presence or absence of a jet containing the $D^{*\pm}$ meson in the event. The parameters of fragmentation functions are extracted for QCD models based on leading order matrix elements and DGLAP or CCFM evolution of partons together with string fragmentation and particle decays. Additionally, they are determined for a next-to-leading order QCD calculation in the fixed flavour number scheme using the independent fragmentation of charm quarks to $D^{*\pm}$ mesons.

20 data tables match query

Normalised D*+- cross section as a function of zJet for the D*+- jet sample.

Normalised D*+- cross section as a function of zHem for the D*+- jet sample.

Normalised D*+- cross section, corrected to the parton level, as a function of zJet for the D*+- jet sample.

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First measurement of the left-right cross-section asymmetry in Z boson production by e+ e- collisions

The SLD collaboration Abe, K. ; Abt, I. ; Acton, P.D. ; et al.
Phys.Rev.Lett. 70 (1993) 2515-2520, 1993.
Inspire Record 352667 DOI 10.17182/hepdata.19765

We present the first measurement of the left-right cross section asymmetry (ALR) for Z boson production by e+e− collisions. The measurement was performed at a center-of-mass energy of 91.55 GeV with the SLD detector at the SLAC Linear Collider which utilized a longitudinally polarized electron beam. The average beam polarization was (22.4±0.6)%. Using a sample of 10 224 Z decays, we measure ALR to be 0.100±0.044(stat)±0.004(syst), which determines the effective weak mixing angle to be sin2θWeff=0.2378 ±0.0056(stat)±0.0005(syst).

2 data tables match query

R and L refer to Right and Left handed beam polarization.

Effective weak mixing angle.


Local particle densities and global multiplicities in central heavy ion interactions at 3.7-A/GeV, 14.6-A/GeV, 60-A/GeV and 200-A/GeV

The EMU01 collaboration Adamovich, M.I. ; Aggarwal, M.M. ; Alexandrov, Y.A. ; et al.
Z.Phys.C 56 (1992) 509-520, 1992.
Inspire Record 334794 DOI 10.17182/hepdata.9290

The energy and centrality dependence of local particle pseudorapidity densities as well as validity of various parametrizations of the distributions are examined. The dispersion, σ, of the rapidity density distribution of produced particles varies slowly with centrality and is 0.80, 0.98, 1.21 and 1.41 for central interactions at 3.7, 14.6, 60 and 200A GeV incident energy, respectively, σ is found to be independent of the size of the interacting system at fixed energy. A novel way of representing the window dependence of the multiplicity as normalized variance versus inverse average multiplicity is outlined.

4 data tables match query

No description provided.

NUCLEUS IS AGBR, CENTRAL EVENTS.

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