Date

A Precision measurement of the prompt photon cross-section in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 2662-2666, 1994.
Inspire Record 375582 DOI 10.17182/hepdata.19680

A prompt photon cross section measurement from the Collider Detector at Fermilab experiment is presented. Detector and trigger upgrades, as well as 6 times the integrated luminosity compared with our previous publication, have contributed to a much more precise measurement and extended PT range. As before, QCD calculations agree qualitatively with the measured cross section, but the data has a steeper slope than the calculations.

1 data table

Note that the sytematic uncertainties are approximately 100 pct correlated bin to bin.


Inclusive pi0 production in p C and p Cu interactions at 4.5-GeV/c

Abraamian, Kh.U. ; Izyurov, V.M. ; Kozhin, M.A. ; et al.
Phys.Atom.Nucl. 59 (1996) 252-256, 1996.
Inspire Record 382328 DOI 10.17182/hepdata.17174

None

1 data table

THE CROSS SECTION HAS BEEN FITTED BY THE FORMULA: D(SIG)/D(PT**2)= CONST*EXP(-SLOPE*PT**2).


Spin asymmetry in muon proton deep inelastic scattering on a transversely-polarized target.

The Spin Muon (SMC) collaboration Adams, D. ; Adeva, B. ; Arik, E. ; et al.
Phys.Lett.B 336 (1994) 125-130, 1994.
Inspire Record 375478 DOI 10.17182/hepdata.48344

We measured the spin asymmetry in the scattering of 100 GeV longitudinally-polarized muons on transversely polarized protons. The asymmetry was found to be compatible with zero in the kinematic range $0.006<x<0.6$, $1<Q~2<30\,\mbox{GeV}~2$. {}From this result we derive the upper limits for the virtual photon--proton asymmetry $A_2$, and for the spin structure function $g_2$. For $x<0.15$, $A_2$ is significantly smaller than its positivity limit $\sqrt{R}$.

2 data tables

No description provided.

Nucleon spin structure function g2.


Proton total reaction cross-sections for Ca-42, Ca-44, and Ca-48 between 21 and 48 MeV

Carlson, R.F. ; Cox, A.J. ; Davison, N.E. ; et al.
Phys.Rev.C 49 (1994) 3090-3097, 1994.
Inspire Record 389447 DOI 10.17182/hepdata.25987

Proton total reaction cross sections (σR) have been measured for the nuclei Ca42, Ca44, and Ca48 at seven energies each between 20.8 and 48.0 MeV. The experimental results plus our previously measured σR values for Ca40 are compared to the results of optical model analyses, both nonrelativistic and relativistic, of an extensive set of elastic scattering data for the same calcium isotopes in this energy range. The experimental results are also compared to global optical model predictions. In general, the theoretical values are in good agreement with the experimental results, with a slight preference for the relativistic analysis. In addition, our results are used in nuclear transparency calculations, which show that over the range of energies studied, the average nuclear transparency decreases by almost 15%.

2 data tables

No description provided.

No description provided.


J / psi, upsilon-prime ---> mu+ mu- and B ---> J / psi, psi-prime cross-sections

The CDF collaboration
FERMILAB-CONF-94-136-E, 1994.
Inspire Record 375758 DOI 10.17182/hepdata.43047

This paper presents a measurement of J/psi,psi(2S) differential cross sections in p-pbar collisions at square root s = 1.8 TeV. The cross sections are measured above 4 GeV/c in the central region (|eta| &lt; 0.6) using the dimuon decay channel. The fraction of events from B decays is measured, and used to calculate b quark cross sections and direct J/psi,psi(2S) cross sections. The direct cross sections are found to be more than an order of magnitude above theoretical expectations.

3 data tables

Cross sections are multiplied on branching ratio of J/PSI or PSI(2S), respectively.

The cross sections was evaluated form the J/PSI spectrum. The error is statistical and systematic errors, added in quadrature.

The cross sections was evaluated form the PSI(2S) spectrum. The error is statistical and systematic errors, added in quadrature.


Measurement of the B meson differential cross-sections in p anti-p collisions at S**(1/2) = 1.8-TeV using the exclusive decays B+- ---> J / psi K+- and B0 ---> J / psi K*0

The CDF collaboration
FERMILAB-CONF-94-141-E, 1994.
Inspire Record 374778 DOI 10.17182/hepdata.43064

None

4 data tables

Charged B+ or B- meson cross section.

Charged B+ or B- meson cross section.

Neutral B0 or BBAR0 meson cross section.

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Beam flavor dependence in the hadroproduction of D+- and D(s)+- mesons

The E769 collaboration Wallace, A. ; Alves, G.A. ; Amato, S. ; et al.
FERMILAB-CONF-94-184-E, 1994.
Inspire Record 375038 DOI 10.17182/hepdata.43049

None

10 data tables

No description provided.

No description provided.

No description provided.

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Measurement of the electromagnetic form-factor of the proton in the timelike region

Antonelli, A. ; Baldini, R. ; Bertani, M. ; et al.
Phys.Lett.B 334 (1994) 431-434, 1994.
Inspire Record 377833 DOI 10.17182/hepdata.28572

The cross section for the process e + e − → p p has been measured in the s range 3.6–5.9 GeV 2 by the FENICE experiment at the e + e − Adone storage ring and the proton electromagnetic form factor has been extracted.

2 data tables

Cross section measurement.

Proton form-factor measurement.


Measurement of the polarization of Lambda0, anti-Lambda0, Sigma+ and Xi- produced in a Sigma- beam of 330-GeV/c

The WA89 collaboration Adamovich, M.I. ; Albertson, E. ; Alexandrov, Yu. A. ; et al.
Z.Phys.A 350 (1995) 379-386, 1995.
Inspire Record 375458 DOI 10.17182/hepdata.48194

The polarization of Lambda0, AntiLambda0, Sigma+ and Xi- inclusively produced in Sigma- induced interactions at 330 GeV has been measured in the experiment WA89 at CERN. This is the first measurement of polarization of baryons produced by a hyperon beam. No polarization of AntiLambda is observed, as was also the case in proton beam data. At transverse momenta of about 1GeV/c Lambda0 and Sigma+ show little polarization, significantly lower than in the proton beam data, while Xi- have a polarization comparable to the polarization of Lambda0 produced in proton beams.

3 data tables

Target Consisted of a copper and a carbon block arranged side by side.

Target Consisted of a copper and a carbon block arranged side by side.

Target Consisted of a copper and a carbon block arranged side by side.


Measurements of cross-section and charge asymmetry for e+ e- ---> mu+ mu- and e+ e- ---> tau+ tau- at s**(1/2) = 57.8-GeV

The AMY collaboration Velissaris, C. ; Lusin, S. ; Chung, Y.S. ; et al.
Phys.Lett.B 331 (1994) 227-235, 1994.
Inspire Record 373861 DOI 10.17182/hepdata.38344

With data corresponding to 142 pb −1 accumulated at s = 57.8 GeV by the AMY detector at TRISTAN we measure the cross section of the reactions e + e − → μ + μ − and e + e − → τ + τ − and the symmetry in the angular distributions. For the lowest order cross section we obtain σ μμ = 27.54 ± 0.65 ± 0.95 pb and σ ττ = 28.27 ± 0.87 ± 0.69 pb, and for the forward-backward asymmetry, A μμ = 0.303 ± 0.027 ± 0.008 and A ττ = −0.291 ± 0.040 ± 0.019. These measurements agree with the standard model. Assuming e − μ − τ univrsality we extract the vector and axial coupling constants | gν | = 0.00 ± 0.09 and | g A | = 0.476 ± 0.024. A fit of data to composite models places lower bounds (95% confidence level) on the compositeness scale of 2–4 TeV.

5 data tables

Lowest order cross section and forward-backward asymmetry.

Errors are statistical only.

Lowest order cross section and forward-backward asymmetry.

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