HEPData Search

Showing 10 of 44 results

Delbrueck scattering at energies 140-MeV to 450-MeV.

Akhmadalev, S.Z. ; Kezerashvili, G.Ya. ; Klimenko, S.G. ; et al.

BUDKER-INP-1998-51, 1998.

Inspire Record 472470 DOI 10.17182/hepdata.50144

The differential cross section of Delbr\"{u}ck scattering is measured on a bismuth germanate $Bi_4Ge_3O_{12}$ target at photon energies $140 - 450 MeV$ and scattering angles $2.6 - 16.6 mrad$. A good agreement with the theoretical results, obtained exactly in a Coulomb field, is found.

1 data table match query

Table 1

Axis error includes +- 1.5/1.5 contribution (Error of measurement of the initial photons intensity).

Si-28 (S-32) fragmentation at 3.7-A/GeV, 14.6-A/GeV and 200-A/GeV

The EMU1 collaboration Adamovich, M.I. ; Aggarwal, M.M. ; Alexandrov, Y.A. ; et al.

Z.Phys.A 351 (1995) 311-316, 1995.

Inspire Record 407109 DOI 10.17182/hepdata.16506

The fragmentation topology of28Si at 3.7A GeV and 14.6A GeV and32S at 200A GeV in reactions with emulsion nuclei is presented. The fragmentation cross sections are very similar at all three energies. A statistical percolation model can qualitatively describe the data forZ≥ 6. The He production is underestimated and the 3 ≤Z ≤ 5 fragments overestimated by this model.

6 data tables match query

Table 1

JINR.

Table 2

BNL-815.

Table 3

CERN-EMU-001.

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First Measurement of ZZ Production in panti-p Collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Aaltonen, T. ; Adelman, Jahred A. ; Akimoto, T. ; et al.

Phys.Rev.Lett. 100 (2008) 201801, 2008.

Inspire Record 778518 DOI 10.17182/hepdata.42695

We report the first measurement of the cross section for Z boson pair production at a hadron collider. This result is based on a data sample corresponding to 1.9 fb-1 of integrated luminosity from ppbar collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. In the llll channel, we observe three ZZ candidates with an expected background of 0.096^{+0.092}_{-0.063} events. In the llnunu channel, we use a leading-order calculation of the relative ZZ and WW event probabilities to discriminate between signal and background. In the combination of llll and llnunu channels, we observe an excess of events with a probability of $5.1\times 10^{-6}$ to be due to the expected background. This corresponds to a significance of 4.4 standard deviations. The measured cross section is sigma(ppbar -> ZZ) = 1.4^{+0.7}_{-0.6} (stat.+syst.) pb, consistent with the standard model expectation.

1 data table match query

Table 1

Measured cross section. Errors are combined statistics and systematics.

Polarization of J / psi and psi(2S) mesons produced in p anti-p collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Abulencia, A. ; Adelman, Jahred A. ; Affolder, T. ; et al.

Phys.Rev.Lett. 99 (2007) 132001, 2007.

Inspire Record 747876 DOI 10.17182/hepdata.42742

We have measured the polarizations of J/ψ and ψ(2S) mesons as functions of their transverse momentum pT when they are produced promptly in the rapidity range |y|<0.6 with pT≥5 GeV/c. The analysis is performed using a data sample with an integrated luminosity of about 800 pb−1 collected by the CDF II detector. For both vector mesons, we find that the polarizations become increasingly longitudinal as pT increases from 5 to 30 GeV/c. These results are compared to the predictions of nonrelativistic quantum chromodynamics and other contemporary models. The effective polarizations of J/ψ and ψ(2S) mesons from B-hadron decays are also reported.

2 data tables match query

Table 1

Polarization parameter ALPHA for J/PSI production.

Table 2

Polarization parameter ALPHA for PSI(2S) production.

Measurement of the p anti-p ---> t anti-t production cross- section and the top quark mass at s**(1/2) = 1.96-TeV in the all-hadronic decay mode

The CDF collaboration Aaltonen, T. ; Abulencia, A. ; Adelman, J. ; et al.

Phys.Rev.D 76 (2007) 072009, 2007.

Inspire Record 753979 DOI 10.17182/hepdata.42731

We report the measurements of the t anti-t production cross section and of the top quark mass using 1.02 fb^-1 of p anti-p data collected with the CDFII detector at the Fermilab Tevatron. We select events with six or more jets on which a number of kinematical requirements are imposed by means of a neural network algorithm. At least one of these jets must be identified as initiated by a b-quark candidate by the reconstruction of a secondary vertex. The cross section is measured to be sigma_{tt}=8.3+-1.0(stat.)+2.0-1.5(syst.)+-0.5(lumi.) pb, which is consistent with the standard model prediction. The top quark mass of 174.0+-2.2(stat.)+-4.8(syst.) GeV/c^2 is derived from a likelihood fit incorporating reconstructed mass distributions representative of signal and background.

1 data table match query

Table 1

Total cross section measurement. The second DSYS error is the uncertainty on the luminosity.

rivet Analysis
Measurement of the cross section for W-boson production in association with jets in ppbar collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Aaltonen, T. ; Adelman, J. ; Akimoto, T. ; et al.

Phys.Rev.D 77 (2008) 011108, 2008.

Inspire Record 768579 DOI 10.17182/hepdata.42714

We present a measurement of the cross section for W-boson production in association with jets in pbarp collisions at sqrt(s)=1.96$ TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb^-1 collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W+>= n-jet sample ($n= 1 - 4$) we measure sigma(ppbar =>W+>=n$-jet)x BR(W => e nu) with respect to the transverse energy E_T of the n^th-highest E_T jet above 20 GeV, for a restricted W => e nu decay phase space. The cross sections, corrected for all detector effects, can be directly compared to particle level W+ jet(s) predictions. We present here comparisons to leading order and next-to-leading order predictions.

9 data tables match query

Table 1

Measured ET differential cross section of the 1st jet in >= 1 JET plus W < E NU > events.

Table 2

Measured ET differential cross section of the 2nd jet in >= 2 JET plus W < E NU > events.

Table 3

Measured ET differential cross section of the 3rd jet in >= 3 JET plus W < E NU > events.

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Critical behaviour in Au fragmentation at 10.7-A-GeV.

The EMU-1 collaboration Adamovich, M.I. ; Aggarwal, M.M. ; Alexandrov, Y.A. ; et al.

Eur.Phys.J.A 1 (1998) 77-83, 1998.

Inspire Record 467240 DOI 10.17182/hepdata.43765

The complete charge distribution of products from Au nuclei fragmenting in nuclear emulsion at 10.7A GeV has been measured. Multiplicities of produced particles and particles associated with the targe

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
A Measurement of J / psi decay widths

The BES collaboration Bai, J.Z. ; Chen, G.P. ; Chen, H.F. ; et al.

Phys.Lett.B 355 (1995) 374-380, 1995.

Inspire Record 39870 DOI 10.17182/hepdata.28500

The cross sections for e + e − → hadrons, e + e − , μ + μ − have been measured in the vicinity of the J Ψ resonance using the BES detector operated at BEPC. The partial widths for J Ψ to hadrons, electrons, muons and the total width have been determined to be Γ h = 74.1 ± 8.1 keV, Γ e = 5.14 ± 0.39 keV, Γ μ = 5.13 ± 0.52 keV, and Γ = 84.4 ± 8.9 keV, respectively.

1 data table match query

Table 1

No description provided.

Rescattering probed by the emission of slow target associated particles in high-energy heavy ion interactions

The EMU01 collaboration Adamovich, M.I ; Aggarwal, M.M ; Alexandrov, Y.A ; et al.

Phys.Lett.B 363 (1995) 230-236, 1995.

Inspire Record 406952 DOI 10.17182/hepdata.28438

In this letter the distribution of slow target associated particles emitted in Au + Emulsion interactions at 11.6 A GeV/ c is studied. The three models RQMD, FRITIOF and VENUS are used for comparisons and especially their treatment of rescattering is investigated.

6 data tables match query

Table 1

No description provided.

Table 2

PROJECTILE ASSOCIATED HE-FRAGMENTS.

Table 3

No description provided.