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TOTAL, ELASTIC AND INCLUSIVE SINGLE DIFFRACTIVE CROSS-SECTIONS IN ALPHA-ALPHA COLLISIONS AT THE CERN INTERSECTING STORAGE RINGS

Lloyd Owen, D. ; Paternoster, G. ; Patricelli, S. ; et al.
Nucl.Phys.B 274 (1986) 685-706, 1986.
Inspire Record 227125 DOI 10.17182/hepdata.33694

We present measurements of the total interaction cross section and of the single-diffractive dissociation cross section in αα collisions at √ s = 126 GeV. The result obtained for the total cross section, σ tot = (315±18) mb, is a substantial improvement on the precision of earlier measurements. Earlier elastic data were re-analysed, incorporating, through the optical theorem, the present σ tot measurement, resulting in improved determinations of the forward slope, b − t <0.07 = (87±4) GeV −2 , and of the integrated elastic cross section, σ el = (58±6) mb. The single-diffractive differential cross section falls exponentially with momentum transfer at small values of t with a slope b sd = (19.3 ± 0.6) GeV −2 . The integrated single-diffractive cross section is σ sd = (16.6±2.5) mb. The topology of charged tracks resulting from the disintegration of the α in single-diffractive events reveals a two-component distribution. The cross section data are compared with multiple-scattering models.

2 data tables
Table 1

Total cross section by total rate method. Systematic errors included.

Table 2

Reanalysis using data from ISR experiments R-418, and R-807.


Determination of Proton Nucleon Analyzing Powers and Spin Rotation Depolarization Parameters at 500-{MeV}

Marshall, J.A. ; Barlett, M.L. ; Fergerson, R.W. ; et al.
Phys.Rev.C 34 (1986) 1433-1438, 1986.
Inspire Record 240068 DOI 10.17182/hepdata.26283

500 MeV p→+p elastic and quasielastic, and p→+n quasielastic, analyzing powers (Ay) and spin-rotation-depolarization parameters (DSS, DSL, DLS, DLL, DNN) were determined for center-of-momentum angular ranges 6.8°–55.4° (elastic) and 22.4°–55.4° (quasielastic); liquid hydrogen and deuterium targets were used. The p→+p elastic and quasielastic results are in good agreement; both the p→+p and p→+n parameters are well described by current phase shift solutions.

6 data tables
Table 1

The elastic P P analysing power at 500 MeV incident proton energy. There is an additional overall normalization uncertainty of 1 PCT.

Table 2

The spin depolarization and spin rotation parameters in 500 MeV P P elastic interactions. Additional normalization uncertainty of 1 PCT (2 PCT for DLL and DLS).

Table 3

The elastic P P analysing power at 500 MeV incident proton energy. There is an additional overall normalization uncertainty of 1 PCT.

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Measurement of the Spin Correlation Parameters A(ll) and A(sl) for the Reaction $P P \to D \pi^+$ in the Energy Region 500-{MeV} - 800-{MeV}

Barlow, D.B. ; Saha, A. ; Seth, K.K. ; et al.
Phys.Rev.C 37 (1988) 1977-1986, 1988.
Inspire Record 242361 DOI 10.17182/hepdata.26282

Angular distributions of the spin-correlation parameters Asl and All for the reaction pp→π+d have been measured at pion center-of-mass angles 40°≤θπ+*≤130° at incident energies of 500, 650, and 800 MeV. Additional measurements of All were made at 600, 700, and 750 MeV. The results of the experiment are compared with the predictions of several unified coupled-channel calculations and partial-wave analyses. While the latest partial-wave analyses were found to fit the data reasonably well, all except one of the various model predictions not only do not fit the data well, but also tend to be in disagreement with each other. The data show no clear sign of a need for proposed dibaryon resonances.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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SEARCH FOR THE S MESON IN ANTI-PROTON PROTON INTERACTIONS

Fickinger, W. ; Marino, R. ; Robinson, D.K. ; et al.
Phys.Rev.D 34 (1986) 3332-3342, 1986.
Inspire Record 239036 DOI 10.17182/hepdata.26472

The interaction between antiprotons and protons has been studied in the range 1910 to 1990 MeV center-of-mass energy in a drift-chamber experiment at the Brookhaven Alternating Gradient Synchrotron. The total cross section has been determined at eleven different incident momenta, and the elastic cross section between 8 and 30 deg in the laboratory has been measured with an energy resolution of about 5 MeV. The cross section for annihilation into charged mesons has also been measured, with the same resolution. There is no evidence in any of these channels for the existence of a narrow resonance.

3 data tables
Table 1

Data are for total sample with nuclear physics calculation as described in the paper.

Table 2

Partial elastic cross sections.

Table 3

Partial annihilation cross sections.


Neutral and Charged $D^*$ Production in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 169 (1986) 106-112, 1986.
Inspire Record 227059 DOI 10.17182/hepdata.30268

The first data on the production of D ∗ (2010) are presented as observed in π − -proton interactions at √ s = 27 GeV . It is found that D ∗ (2010) dominates the total charm D-meson production, without a significant non-central component.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Observation of Double $\phi$ Meson Production in the Central Region for the Reactions $\pi^+ P \to \pi^+ (K^+ K^+ K^- K^-$) $P$ and $P P \to P (K^+ K^+ K^- K^-$) $P$ at 85-{GeV}/c

The ATHENS-BARI-BIRMINGHAM-CERN collaboration Armstrong, T.A. ; Bloodworth, I.J. ; Carney, J.N. ; et al.
Phys.Lett.B 166 (1986) 245-248, 1986.
Inspire Record 228698 DOI 10.17182/hepdata.30307

The reactions π + p → π + ( K + K + K − K − ) p and pp → p ( K + K + K − K − ) p in which the K + K + K − K − system is centrally produced have been studied at 85 GeV c . Evidence is found for φφ production. The relative rates for production of φφ , φK + K − and K + K + K − K − have been determined.

1 data table
Table 1

No description provided.


High-energy Photoproduction of Large Transverse Momentum $\pi^0$ Mesons: A Quantitative Test of {QCD}

The NA14 collaboration Auge, E. ; Barate, R. ; Bloch, D. ; et al.
Phys.Lett.B 168 (1986) 163-169, 1986.
Inspire Record 227057 DOI 10.17182/hepdata.30278

The first results on inclusive photoproduction of π 0 at transverse momenta up to 4 GeV/ c , using incident γ energies between 50 and 150 GeV are presented. A comparison is made with inclusive π 0 production obtained, in the same experiment, with incident π − . Using the π − data to parametrize the hadronic behaviour of the photon, significant differences are observed in quantitative agreement with QCD Compton scattering and corrections thereof.

2 data tables
Table 1

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.

Table 2

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.


Analyzing Powers in Free $N$ (Polarized) $P$ Forward Elastic Scattering at Energies From 630-{MeV} to 1000-{MeV}

Korolev, G.A. ; Khanzadeev, A.V. ; Petrov, G.E. ; et al.
Phys.Lett.B 165 (1985) 262-264, 1985.
Inspire Record 228528 DOI 10.17182/hepdata.30310

The analysing powers in free →n p forward elastic scattering have been measured for incident neutron energies of 633, 784, 834, 934 and 985 MeV, and for momentum transfer 0.01 < ‖ t ‖ < 0.10 ( GeV / c ) 2 . The experiment used a recoil detector ionisation chamber which served at the same time as a gas target, and scintillation counters to measure the asymmetry of the scattered neutrons.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Rapidity Dependence of the Charged Particle Multiplicity Distributions in e+ e- Annihilation at 29-GeV

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Phys.Lett.B 168 (1986) 299-304, 1986.
Inspire Record 17794 DOI 10.17182/hepdata.30277

The charged particle multiplicity distribution for e + e − annihilations at s = 29 GeV has been measured using the High Resolution Spectrometer at PEP. The multiplicity distribution, expressed as a function of the mean, shows KNO scaling when compared to e + e − data at other energies. Multiplicity distributions for particles selected in different central rapidity spans are presented. All of these are well presented by the Negative binomial distribution. As the rapidity span is narrowed, the distributions become broader and approach a constant value of the parameter k .

12 data tables
Table 1

KNO charged multiplicity distributions for the Inclusive Data Sample. The numerical values are calculated from the multiplicity distributions given in Derrick et al., PR D34,3304.

Table 2

Folded rapidity distribution measured along the thrust axis of the event. Errors are dominated by systematics. All charged particles are assigned the pion mass.

Table 3

KNO charged multiplicity distribution for the Two Jet Data Sample. The numerical values are calculated from the multiplicity distributions given in Derrick et al., PR D34,3304.

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Atomic Beam Measurement of Parity Nonconservation in Cesium

Gilbert, S.L. ; Wieman, Carl E. ;
Phys.Rev.A 34 (1986) 792-803, 1986.
Inspire Record 237319 DOI 10.17182/hepdata.26392

We present a new measurement of parity nonconservation in cesium. In this experiment, a laser excited the 6S→7S transition in an atomic beam in a region of static electric and magnetic fields. The quantity measured was the component of the transition rate arising from the interference between the parity nonconserving amplitude, scrEPNC, and the Stark amplitude, βE. Our results are ImscrEPNC/β=−1.65±0.13 mV/cm and C2p=-2±2, where C2p is the proton-axial-vector–electron-vector neutral-current coupling constant. These results are in agreement with previous less precise measurements in cesium and with the predictions of the electroweak standard model. We give a detailed discussion of the experiment with particular emphasis on the treatment and elimination of systematic errors. This experimental technique will allow future measurements of significantly higher precision.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).