Banerjee, S.
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Study of anti-n p --> phi pi+ and anti-n p --> omega pi+ annihilation reactions in flight.

The OBELIX collaboration Filippi, A. ; Agnello, M. ; Balestra, F. ; et al.
Nucl.Phys.A 655 (1999) 453-494, 1999.
Inspire Record 512679 DOI 10.17182/hepdata.36158

The results of a study of the annihilation reactions n p → θπ + and n p → ωπ + are reported; the data were collected by the OBELIX apparatus, with antineutrons annihilating in flight (momenta from ∼ 50 MeV/ c to 405 MeV/ c ). Annihilation frequencies and annihilation cross sections have been deduced, for both channels, as a function of antineutron momentum. From the cross section ratio, a substantial deviation from OZI rule expectations is observed. An s s quark content in the nucleon offers a fairly plausible explanation for such an effect.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Antinuclei production in heavy ion collisions at CERN SPS.

The NA52 collaboration Arsenescu, R. ; Baglin, C. ; Beck, H.P. ; et al.
Nucl.Phys.A 661 (1999) 177-184, 1999.
Inspire Record 514756 DOI 10.17182/hepdata.36135

Besides the dedicated search for strangelets NA52 measures light (anti)particle and (anti)nuclei production over a wide range of rapidity. Compared to previous runs the statistics has been increased in the 1998 run by more than one order of magnitude for negatively charged objects at different spectrometer rigidities. At a rigidity of −20 GeV/ c we measured 10 6 p , 10 3 d and one 3 He without any centrality requirements. These preliminary results together with previous measurements near central rapidity are discussed in the framework of a thermodynamical and a coalescence model.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of W and Z boson production cross-sections

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.D 60 (1999) 052003, 1999.
Inspire Record 494696 DOI 10.17182/hepdata.42125

DO has measured the inclusive production cross section of W and Z bosons in a sample of 13 pb$^{-1}$ of data collected at the Fermilab Tevatron. The cross sections, multiplied by their leptonic branching fractions, for production in pbar-p collisions at sqrt{s}=1.8 TeV are sigma_W*B(W->e nu) = 2.36+-0.02+-0.08+-0.13 nb, sigma_W*B(W->mu nu) = 2.09+-0.06+-0.22+-0.11 nb, sigma_Z*B(Z->e+ e-) = 0.218+-0.008+-0.008+-0.012 nb, and sigma_Z*B(Z->mu+ mu-) = 0.178+-0.022+-0.021+-0.009 nb, where the first uncertainty is statistical and the second systematic; the third reflects the uncertainty in the integrated luminosity. For the combined electron and muon analyses, we find sigma_W*B(W->l mu)/sigma_Z*B(Z->l+ l-) = 10.90+-0.52. Assuming standard model couplings, we use this result to determine the width of the W boson, and obtain Gamma(W) = 2.044+-0.097 GeV.

2 data tables
Table 1

No description provided.

Table 2

Combined electron and muon analysis.


Measurement of the top quark pair production cross section in the all-jets decay channel

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 83 (1999) 1908-1913, 1999.
Inspire Record 494099 DOI 10.17182/hepdata.42119

We present a measurement of tbar-t production using multijet final states in pbar-p collisions at a center-of-mass energy of 1.8 TeV, with an integrated luminosity of 110.3 pb(-1). The analysis has been optimized using neural networks to achieve the smallest expected fractional uncertainty on the tbar-t production cross section, and yields a cross section of 7.1 +/- 2.8(stat.) +/- 1.5(syst.) pb, assuming a top quark mass of 172.1 GeV/c^(2). Combining this result with previous D0 measurements, where one or both of the W bosons decay leptonically, gives a tbar-t production cross section of 5.9 +/- 1.2(stat) +/- 1.1(syst) pb.

1 data table
Table 1

No description provided.


Differential cross section for the reaction C-12(d,p)X at a primary momentum of 9-GeV/c and its tensor and vector analyzing powers.

Azhgirei, L.S. ; Arkhipov, V.V. ; Afanasev, S.V. ; et al.
Phys.Atom.Nucl. 62 (1999) 1673-1686, 1999.
Inspire Record 513982 DOI 10.17182/hepdata.17059

None

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Deep-subthreshold eta and pi0 production probing pion dynamics in the reaction Ar + Ca at 180-A-MeV.

Martinez, G. ; Charbonnier, Y. ; Aphecetche, L. ; et al.
Phys.Rev.Lett. 83 (1999) 1538-1541, 1999.
Inspire Record 508818 DOI 10.17182/hepdata.19447

We report on a measurement of subthreshold η and π0 mesons in the reaction Ar+Ca at 180A MeV. We find that the ratio of the η to π0 meson-production cross section is more than a factor of 20 smaller than the one expected from threshold-energy scaling of meson production. In addition, the multiplicity of high mt π0 increases faster with the centrality of the reaction than the multiplicity of the bulk of π0 mesons. This behavior is explained by the rescattering of π mesons in nuclear matter at the origin of most energetic particles.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


New measurement of the anomalous magnetic moment of the positive muon

Carey, R.M. ; Earle, W. ; Efstathiadis, E. ; et al.
Phys.Rev.Lett. 82 (1999) 1632-1635, 1999.
Inspire Record 500172 DOI 10.17182/hepdata.19493

The muon anomalous magnetic moment has been measured in a new experiment at Brookhaven. Polarized muons were stored in a superferric ring, and the angular frequency difference, ωa, between the spin precession and orbital frequencies was determined by measuring the time distribution of high-energy decay positrons. The ratio R of ωa to the Larmor precession frequency of free protons, ωp, in the storage-ring magnetic field was measured. We find R=3.707220(48)×10−3. With μμ/μp=3.18334547(47) this gives aμ+=1165925(15)×10−9 ( ±13ppm), in good agreement with the previous CERN measurements for μ+ and μ− and of approximately the same precision.

1 data table
Table 1

The anomalous g value is related to the gyromagnetic ratio by MOM(NAME=ANOMALOUS MAGNETIC) = (G-2)/2. The beam momentum spread is about 1 PCT.


Analyzing powers and partial wave decomposition of p n --> p p((1)S(0)) pi- at low energies.

Hahn, H. ; Duncan, F.A. ; Aclander, J. ; et al.
Phys.Rev.Lett. 82 (1999) 2258-2261, 1999.
Inspire Record 500174 DOI 10.17182/hepdata.19495

Analyzing powers for p→n→pp(S01)π− were measured at beam energies 353, 404, and 440 MeV by extracting the quasifree process from p→d→pppπ−. Partial wave amplitude analysis yields a significant contribution from the isospin 1, s-wave channel. This contribution is relatively much larger than that expected from theoretical models which have been successful in describing the isospin 1, s-wave channel behavior of pp→ppπ0 cross sections at threshold.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////).


rivet Analysis
Precise measurement of the total hadronic cross section in e+ e- annihilation at s**(1/2) = 57.77-GeV.

The VENUS collaboration Yusa, K. ; Hamasaki, H. ; Mori, S. ; et al.
Phys.Lett.B 447 (1999) 167-177, 1999.
Inspire Record 500179 DOI 10.17182/hepdata.5548

The total hadronic cross section in e + e − annihilation has been measured at s = 57.77 GeV using 290 pb −1 data sample collected with the VENUS detector at KEK TRISTAN. The cross section obtained is 140.3 ±1.8 pb for s ′/ s ≥0.5, where s ′ is the square of the invariant mass of the final state hadrons. The present result together with the recent results from the LEP collaborations is used to determine the hadronic γ − Z 0 interference parameter, j tot had , to be 0.196±0.083. The result is in good agreement with the Standard Model prediction of 0.220.

2 data tables
Table 1

The statistical and systematic errors are added in quadrature.

Table 2

No description provided.


Simultaneous multiplicity and forward energy characterization of particle spectra in Au + Au collisions at 11.6-A-GeV/c.

The E-802 collaboration Ahle, L. ; Akiba, Y. ; Ashktorab, K. ; et al.
Phys.Rev.C 59 (1999) 2173-2188, 1999.
Inspire Record 501648 DOI 10.17182/hepdata.4988

In this paper Au+Au collisions at 11.6A GeV/c are characterized by two global observables: the energy measured near zero degrees (EZCAL) and the total event multiplicity. Particle spectra are measured for different event classes that are defined in a two-dimensional grid of both global observables. For moderately central events (σ/σint<12%) the proton dN/dy distributions do not depend on EZCAL but only on the event multiplicity. In contrast the shape of the proton transverse spectra shows little dependence on the event multiplicity. The change in the proton dN/dy distributions suggests that different conditions are formed in the collision for different event classes. These event classes are studied for signals of new physics by measuring pion and kaon spectra and yields. In the event classes doubly selected on EZCAL and multiplicity there is no indication of any unusual pion or kaon yields, spectra, or K/π ratio even in the events with extreme multiplicity.

48 data tables
Table 1

Table for event classification (from CLASS1 to CLASS8) where ZCAL energy solely used for event selection. Number of Projectile Participants Npp=197*(1-E(P=3)/EKIN(P=1)).

Table 2

CLASS1 (see Table for event classification).

Table 3

CLASS1 (see Table for event classification).

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