HEPData Search

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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

Table 1

Data now superceded.

Determination of $alpha_{s}$ in second order {QCD} from hadronic $Z$ decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.

Z.Phys.C 54 (1992) 55-74, 1992.

Inspire Record 333272 DOI 10.17182/hepdata.14603

Distributions of event shape variables obtained from 120600 hadronicZ decays measured with the DELPHI detector are compared to the predictions of QCD based event generators. Values of the strong coupling constant αs are derived as a function of the renormalization scale from a quantitative analysis of eight hadronic distributions. The final result, αs(MZ), is based on second order perturbation theory and uses two hadronization corrections, one computed with a parton shower model and the other with a QCD matrix element model.

9 data tables match query

Table 1

Experimental differential Thrust distributions.

Table 2

Experimental differential Oblateness distributions.

Table 3

Experimental differential C-parameter distributions.

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rivet Analysis
Charged particle multiplicity distributions in restricted rapidity intervals in Z0 hadronic decays.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.

Z.Phys.C 52 (1991) 271-281, 1991.

Inspire Record 324035 DOI 10.17182/hepdata.14860

The multiplicity distributions of charged particles in restricted rapidity intervals inZ0 hadronic decays measured by the DELPHI detector are presented. The data reveal a shoulder structure, best visible for intervals of intermediate size, i.e. for rapidity limits around ±1.5. The whole set of distributions including the shoulder structure is reproduced by the Lund Parton Shower model. The structure is found to be due to important contributions from 3-and 4-jet events with a hard gluon jet. A different model, based on the concept of independently produced groups of particles, “clans”, fluctuating both in number per event and particle content per clan, has also been used to analyse the present data. The results show that for each interval of rapidity the average number of clans per event is approximately the same as at lower energies.

15 data tables match query

Table 1

Data for both hemispheres.

Table 2

Data for both hemispheres.

Table 3

Data for both hemispheres.

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rivet Analysis
Masses, lifetimes and production rates of Xi- and anti-Xi+ at LEP 1.

The DELPHI collaboration Abdallah, J. ; Abreu, P. ; Adam, W. ; et al.

Phys.Lett.B 639 (2006) 179-191, 2006.

Inspire Record 719387 DOI 10.17182/hepdata.26952

Measurements of the Xi- and anti-Xi+ masses, mass differences, lifetimes and lifetime differences are presented. The anti-Xi+ sample used is much larger than those used previously for such measurements. In addition, the Xi production rates in Z -> b anti-b and Z -> q anti-q events are compared and the position xi* of the maximum of the xi distribution in Z -> q anti-q events is measured.

3 data tables match query

Table 1

Corrected LN(1/X) distribution for (XI- + XIBAR+) production.

Table 2

Measured and extrapoplated production rates.

Table 3

Extrapolated production rate in b-bbar events.

Large angle k+ p elastic scattering at 10 gev/c

Baglin, C. ; Briandet, P. ; Carlson, P.J. ; et al.

Phys.Lett.B 47 (1973) 89-92, 1973.

Inspire Record 95211 DOI 10.17182/hepdata.28014

K + p elastic scattering has been measured over nearly the whole angular range at an incident momentum of 10 GeV/ c . The differential cross-section is found to decrease smoothly in the forward direction to - t ≈ 2 (GeV/ c ) 2 , where there is a change in slope, followed by a further decrease to - t ≈ 6 (GeV/ c ) 2 . Around 90° c.m. the cross-section is approximately 1 nb/(GeV/ c ) 2 , which is more than two orders of magnitude lower than at 5 GeV/ c . The backward peak has no structure.

1 data table match query

Table 1

THESE DATA ARE REPORTED MORE FULLY IN C. BAGLIN ET AL., NP B98, 365 (1975).

NEW RESULTS ON NEUTRAL D MESON PROPERTIES IN 360-GeV/c pi- p INTERACTIONS

Aguilar-Benitez, M. ; Allison, W.W. ; Barr, V.M. ; et al.

IFVE-85-21, 1985.

Inspire Record 223942 DOI 10.17182/hepdata.40961

None

1 data table match query

Table 1

No description provided.

Search for new phenomena using single photon events in the DELPHI detector at LEP

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.

Z.Phys.C 74 (1997) 577-586, 1997.

Inspire Record 415746 DOI 10.17182/hepdata.41128

Data are presented on the reaction e+e− → γ + no other detected particle at centre-of-mass energies of 89.48, 91.26 and 93.08 GeV. The cross-section for this reaction is related directly to the number of light neutrino generations which couple to the Z° boson, and to several other possible phenomena such as the production of excited neutrinos, the production of any invisible ‘X’ particle, and the magnetic moment of the tau neutrino. Based on the observed number of single photon events, the number of light neutrinos that couple to the Z° is measured to be Nv = 2.89 ± 0.38. No evidence is found for anomalous production of energetic single photons, and upper limits at 95% confidence level are determined for excited neutrino production (BR < 4 − 8 × 10−6 depending on its mass), production of an invisible ‘X’ particle (σ, < 0.1 pb for masses below 60 GeV), and the magnetic moment of the tau neutrino (< 5.1 × 10-6 μB).

3 data tables match query

Table 1

No description provided.

Table 2

Limit on an anomalous magnetic moment for tau-neutrino from '1GAMMA + nothing' events. Magnetic moment in Bohr magnetons.

Table 3

Here UNSPEC is invisible particle.

Large angle pi+ p elastic scattering at 10 gev/c

Baglin, C. ; Briandet, P. ; Carlson, P.J. ; et al.

Phys.Lett.B 47 (1973) 85-88, 1973.

Inspire Record 95213 DOI 10.17182/hepdata.28033

The angular distribution of π + p elastic scattering has been measured at an incident momentum of 10 GeV/ c . Nearly the whole angular range was covered in one experimental set-up. The pronounced dip at − t = 2.8 (GeV/ c ) 2 , observed at lower momenta, has diminished and is essentially a shoulder at 10 GeV/ c . The other structure at larger momentum transfers are also different in detail from what we observed at 5 GeV/ c . In the 90° c.m. region the differential cross-section is approximately one nb/(GeV/ c ) 2 , which is more than two orders of magnitude lower than at 5 GeV/ c .

1 data table match query

Table 1

THESE DATA ARE REPORTED MORE FULLY IN C. BAGLIN ET AL., NP B98, 365 (1975).

Anti-p p annihilation into pi+ rho- at 5 gev/c

Eide, A. ; Lehmann, P. ; Lundby, A. ; et al.

Phys.Lett.B 41 (1972) 225-228, 1972.

Inspire Record 75630 DOI 10.17182/hepdata.28228

We have measured the differential cross-section for the reaction p p → π + Λ − at 5 GeV /c , the π + being in t he cm angular range 0.47 < cos θ p π + cm < 0.98 , corresponding to 0.12 < − t < 2.40 (GeV/ c ) 2 . The angular distribution has a forward peak with a differential cross-section d σ d ω = 4.1 ± 1.6 μ b / sr for 0.94 < cos θ p π + cm < 0.96 .

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.