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New Test of Nucleon-Nucleon Potential Models

Holslin, D. ; McAninch, J. ; Quin, P.A. ; et al.

Phys.Rev.Lett. 61 (1988) 1561-1564, 1988.

Inspire Record 945156 DOI 10.17182/hepdata.20124

We present new measurements of the analyzing power for np scattering at 10.03 MeV accurate to ± 1 × 10−3. A new source of systematic error, related to resonances in n−C12 scattering in the neutron detectors, is discussed. The interaction of the neutron magnetic moment with the Coulomb field of the proton is found to make a significant contribution to the analyzing power at the present level of accuracy. The results are compared to predictions of nucleon-nucleon potential models. New, improved values are reported for the p and d-wave spin-orbit phase-shift splittings.

1 data table

Table 1

No description provided.

rivet Analysis
The Pion Electromagnetic Form-factor in the Timelike Energy Range 1.35-{GeV} $\le \sqrt{s} \le$ 2.4-{GeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.

Phys.Lett.B 220 (1989) 321-327, 1989.

Inspire Record 267118 DOI 10.17182/hepdata.29829

The e + e − → π + π − cross section has been measured from about 280 events (an order of magnitude more than the previous world statistics) in the energy interval 1.35 ⩽ s ⩽ 2.4 GeV with the DM2 detector at DCI. The pion squared form factor | F π | 2 shows a deep minimum around 1.6 GeV/ c 2 and is better fit under the hypothesis of two ϱ-like resonance ⋍0.25 GeV/ c 2 wide with 1.42 and 1.77 GeV/ c 2 masses.

1 data table

Table 1

Statistical errors only.

rivet Analysis
A Measurement of $\gamma \gamma \to \rho^+ \rho^-$

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.

Phys.Lett.B 217 (1989) 205-210, 1989.

Inspire Record 266416 DOI 10.17182/hepdata.29853

The reaction γγ → ϱ + ϱ − → π + π − π 0 π 0 has been studied with the ARGUS detector at the e + e − storage ring DORIS II at DESY. Near threshold, the cross section for this reaction is about four times smaller than for the reaction γγ → ϱ 0 ϱ 0 .

4 data tables

Table 1

Data read from graph.

Table 2

Data read from graph.

Table 3

Data read from graph.

More…

rivet Analysis
$K^0(s$) $K \pi$ Production in Tagged and Untagged $\gamma \gamma$ Interactions

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.

Z.Phys.C 42 (1989) 367, 1989.

Inspire Record 266414 DOI 10.17182/hepdata.15529

We have searched for resonance production in the reaction γγ→Ks0Kπ. No signal was found for theηc and an upper limit for the radiative with$\Gamma _{\gamma \gamma }^{\eta _c } $ keV (95% c.l.) is obtained. For the glueball candidate η(1440) (previouslyi) the upper limit$\Gamma _{\gamma \gamma }^{\eta (1440)} B(\eta (1440) \to K\bar K\pi )< 1.2keV(95\% c.l.)$ is derived. In the tagged data sample resonance formation of a spin 1 state at 1420 MeV is observed, which is absent in the untagged data. The mass and width of this state are consistent with those of thef1(1420); an analysis of decay angular distributions favours positive parity.

1 data table

Table 1

Data read from graph.. Additional overall systematic error decreasing from 25% in the lowest mass bins to 15% for M > 2.0 GeV.

Cross-section Measurement of $\pi^- p \to \pi^- \pi^+ n$ Reaction Near Threshold

The OMICRON collaboration Kernel, G. ; Korbar, D. ; Krizan, P. ; et al.

Phys.Lett.B 216 (1989) 244-248, 1989.

Inspire Record 264989 DOI 10.17182/hepdata.29858

Result of cross section measurements for the reaction π − p → π − π + n are presented. They cover a range of incident pion momenta between 295 and 450 MeV/ c . It is the first time that the cross section has been measured so close to threshold. The experiment was performed with Omicron, a large-solid-angle spectrometer, which enables a measurement of the full set of kinematic variables. In the region of overlap there is a good agreement with other experiments. The extracted value for the chiral-symmetry-breaking parameter ξ is seen to be largely extrapolition dependent but the measured value of -0.5±0.8 leaves Weinberg's prediction of ξ =0 the only remaining choice.

1 data table

Table 1

No description provided.

Observation of a New $\Omega^*$- at 2.47-{GeV}/$c^2$ in $K^- p$ Interactions at 11-{GeV}/$c$

Aston, D. ; Awaji, N. ; Bienz, T. ; et al.

Phys.Lett.B 215 (1988) 799-804, 1988.

Inspire Record 264666 DOI 10.17182/hepdata.29872

Clear evidence is presented for an Ω ∗− resonance of mass 2474±12 MeV c 2 and width 72±33 MeV c 2 in K − p interactions at 11 GeV c . The state is observed in the Ω − π + π − decay mode, and the corresponding inclusive cross section, corrected for Ω − π 0 π 0 decay, is estimated to be 290±90 nb.

1 data table

Table 1

Estimated inclusive production cross section in the (omega- pi+ pi-) decay mode (after correction for the omega- 2pi0 decay).

The Transverse Energy Distributions of $^{32}$S Nucleus Collisions at 200-{GeV} Per Nucleon

The HELIOS collaboration Akesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.

Phys.Lett.B 214 (1988) 295-302, 1988.

Inspire Record 265090 DOI 10.17182/hepdata.29873

Transverse-energy distributions have been measured for the collisions of the 32 S nucleus with Al, Ag, W, Pt, Pb, and U target nuclei, at an incident energy of 200 GeV per nucleon. The shapes of these distribution reflect the geometry of the collisions, including the deformation effects. For central collisions, the transverse-energy production in the region −0.1< η lab <2.9 increases approximately as A 0.5 , where A is the atomic mass number of the target. This increase is accompanied by a relative depletion in the forward region η lab > 2.9. These results are compared with those obtained under similar conditions with incident 16 O nuclei. A comparison is also made with the predictions of a Monte Carlo generator based on the dual parton model. Finally, we give estimates of the energy density reached and its dependence on the atomic mass number of the projectile.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.