Read, Alexander L.
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Measurement of the Spin Correlation Parameter A(00nn ($P P$ in a Large Angular Region Between 0.88-{GeV} and 2.7-{GeV}

Lehar, F. ; De Lesquen, A. ; Meyer, J.P. ; et al.
Nucl.Phys.B 294 (1987) 1013-1021, 1987.
Inspire Record 255230 DOI 10.17182/hepdata.33526

The spin correlation parameter A oonn for pp elastic scattering was measured at 0.88, 1.1, 1.3, 1.6, 1.8, 2.1, 2.4 and 2.7 GeV using the SATURNE II polarized proton beam and the Saclay frozen spin polarized target. At the first two energies, the new measurements at θ CM < 50° complete our previous data from 45° to 90°. Between 1.3 and 2.7 GeV the measurements were performed in two overlapping angular regions covering together the CM angles from 28° (at the lower energies) or 18° (at the highest energy) to > 90°. At all energies above 1.3 GeV the angular distribution shows a dip at fixed four-momentum transfer − t ∼ 0.90 (GeV/ c ) 2 . The value of A oonn ( θ CM = 90°) decreases from A oonn (90°) ≅ 0.57 at 0.88 GeV to A oonn (90°) ≅ 0.35 at 2.7 GeV. However, the large value found at 1.8 GeV indicates that the energy dependence is not monotonic.

8 data tables
Table 1

Errors are statistical plus random-like instrumental uncertainties.

Table 2

Errors are statistical plus random-like instrumental uncertainties.

Table 3

Errors are statistical plus random-like instrumental uncertainties.

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Measurement of $N P$ Analyzing Power A(00n0) Using the Deuteron Polarized Beam of Saturne-{II}

Ball, J. ; Lehar, F. ; De Lesquen, A. ; et al.
Nucl.Phys.B 286 (1987) 635-642, 1987.
Inspire Record 248563 DOI 10.17182/hepdata.33621

Both the np and the pp analyzing powers were measured simultaneously using the SATURNE II polarized deuteron beam at 0.550, 0.725, 0.900 and 1.15 GeV/nucleon. The results for the pp analyzing power coincide with the free pp elastic scattering data. We thus can assume that also the np analyzing power is equal to the one for scattering of free polarized neutrons. The np data cover the angular region 90° ≤ θ CM ≤ 125°. Our results for the np analyzing power clarify a discrepancy between earlier data at 0.5 GeV and allow conclusions about the energy dependence of the minimum of polarization at θ CM ⋍ 100° in the region from 0.5 to 0.9 GeV.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the $P P$ Analyzing Power A(00n0) in a Large Angular Region Between 0.88-{GeV} and 2.7-{GeV}

Perrot, F. ; Fontaine, J.M. ; Lehar, F. ; et al.
Nucl.Phys.B 294 (1987) 1001-1012, 1987.
Inspire Record 255229 DOI 10.17182/hepdata.33562

The pp analyzing power was measured using the SATURNE II polarized proton beam and the Saclay frozen spin polarized target. The measurements at 0.88 and 1.1 GeV were carried out in the angular region θ CM from 28° to ≅50° and complete our previous measurements from 45 ° to 90°. Above 1.1 GeV the measurements presented here cover both regions, extending from θ CM = 28° (at the lower energies) or θ CM = 18° (at the higher energies) to θ CM > 90°. The shape of the angular distribution A oono ( pp ) = ƒ(θ CM ) changes considerably with increasing energy. The new data show the onset of a characteristic t -dependence of the analyzing power, with a minimum at − t ≅ 1.0 (GeV/ c ) 2 followed by a second maximum at − t ≅ 1.5 (GeV/ c ) 2 . This structure is present at all energies, from kinematic threshold to 200 GeV.

16 data tables
Table 1

Errors are statistical plus random-like instrumental uncertainties. Results using polarised target.

Table 2

Errors are statistical plus random-like instrumental uncertainties. Results using polarised target.

Table 3

Errors are statistical plus random-like instrumental uncertainties. Results using polarised target.

More…

Measurement of Anti-neutron Proton Total and Annihilation Cross-sections From 100-{MeV}/c to 500-{MeV}/c

The BROOKHAVEN-HOUSTON-PENNSYLVANIA STATE-RICE collaboration Armstrong, T. ; Chu, C. ; Clement, J. ; et al.
Phys.Rev.D 36 (1987) 659-673, 1987.
Inspire Record 253128 DOI 10.17182/hepdata.26943

Total and annihilation n¯p cross sections from 100 to 500 MeV/c are reported, the first such measurements with good statistics in this momentum range. These cross sections are well represented by A+B/p, where p is the incident antineutron momentum, and are in agreement with previous n¯p and p¯n measurements. A comparison of these cross sections with phenomenological potential model calculations is good overall. However, the microscopic quark model gives unsatisfactory predictions. The agreement between previous p¯p annihilation cross sections and n¯p cross sections above 300 MeV/c is excellent. The total n¯p cross section is lower than the total p¯p cross section in this momentum range. Both of these types of behavior are predicted by potential models. The anticipated availability of future p¯p data below 300 MeV/c should indicate whether these trends continue at lower momenta.

1 data table
Table 1

No description provided.


Forward and Transverse Energy Distributions in Oxygen Induced Reactions at 60-agev and 200-agev

The WA80 collaboration Albrecht, R. ; Awes, T.C. ; Baktash, C. ; et al.
Phys.Lett.B 199 (1987) 297-303, 1987.
Inspire Record 254598 DOI 10.17182/hepdata.30059

Results are presented from reactions of 60 A GeV and 200 A GeV 16 O projectiles with C, Cu, Ag, and Au nuclei. Energy spectra measured at zero degrees and transverse energy distributions in the pseudorapidity range from 2.4 to 5.5 are shown. The average transverse energy per participant is found to be nearly independent of target mass. Estimates of nuclear stopping and of attained energy densities are made.

1 data table
Table 1

STOPPING POWER IS THE QUANTITY GIVEN IN THIS TABLE. IT IS DEFINED AS ( D(ET(EXP)/D(ETA) / D(ET(THEORY)/D(ETA) ) AND THE DENOMINATOR IS TAKEN TO BE 0.5*E(HADRON IN CM). ETA IS THE PSEUDO-RAPIDITY.


Measurement of the Two Photon Reaction $\gamma \gamma \to \pi^+ \pi^- \pi^+ \pi^-$ at Large Values of $Q^2$

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 41 (1988) 353-357, 1988.
Inspire Record 250570 DOI 10.17182/hepdata.15557

The process γγ→π+π−π+π− has been investigated in reactions of the typee+e−→e+e−π+π−π+π− in the single tag mode. The range of the four momentum squared of one of the virtual photons was 0.28 GeV2/c2≦Q2≦3.6 GeV2/c2, the average being 〈Q2〉=0.92 GeV2/c2; the other photon was quasi real. The reaction is mainly described by the channels γγ→ρ0ρ0 and γγ→4π (phase space), occuring with about equal probability. TheQ2-dependence of the cross section is in agreement with the ρ form factor.

2 data tables
Table 1

Data read from graph.. Additional overall systematic error 25%.

Table 2

Data read from graph.. Additional overall systematic error 25%.. The Q**2 approx 0 datum is deduced from the earlier TASSO paper, Brandelik et al, Phys. Lett. 97B(1980)448, (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1151> RED = 1151 </a>) on rho0 rho0 production.


Single Diffraction Dissociation in $\pi^+ p$ and $K^+ p$ Interactions at 250-{GeV}/$c$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Almeida, F.M.L., Jr. ; et al.
Z.Phys.C 39 (1988) 301, 1988.
Inspire Record 254506 DOI 10.17182/hepdata.15646

None

1 data table
Table 1

No description provided.


NEUTRAL STRANGE PARTICLE PRODUCTION IN HIGH TRANSVERSE MOMENTUM pi- NUCLEUS INTERACTIONS AT approximately 40-GeV/c

The RISK collaboration Barwolff, H. ; Dreher, C. ; Friebel, W. ; et al.
Z.Phys.C 37 (1988) 337, 1988.
Inspire Record 251304 DOI 10.17182/hepdata.15678

Measurements ofKs0, Λ and\(\bar \Lambda \) production in π− nucleus (C, Cu, Pb) interactions are presented. The experiment was carried out with the streamer chamber spectrometer RISK using a π− beam of ∼40 GeV/c and a trigger requiring a secondary charged particle with transverse momentum above 1.1 GeV/c. Production cross sections, relative production rates and distributions of Feynmanx and transverse momentum squared as well as correlations between theV0 and the trigger particle are presented. The results are compared and found to be in agreement withKs0, Λ and\(\bar \Lambda \) data from untriggered π−p and π−C interactions, except for the relative production rate of antilambdas which is about to times larger in high-pt collisions. Our results can be well interpreted within the dual topological unitarization model.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


E+ E- PAIR PRODUCTION BY A SYNCHROTRON RADIATION PHOTON ON A COUNTER BEAM ELECTRON. (IN RUSSIAN)

Blinov, A.E. ; Bondar, A.F. ; Bukin, A.D. ; et al.
Yad.Fiz. 45 (1987) 1008-1014, 1987.
Inspire Record 256613 DOI 10.17182/hepdata.17424

None

3 data tables
Table 1

Axis error includes +- 2/2 contribution (Error in counter efficiency determination).

Table 2

Electron momentum distribution.

Table 3

Electron-positron pairs mass distribution.


Observation of the Tensor X (1810) Meson in 300-{GeV} Central $\pi^- N$ Collisions (In Russian)

The IHEP-IISN-LANL-LAPP-PISA collaboration Alde, D. ; Bellazzini, R. ; Binon, F.G. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 810-812, 1988.
Inspire Record 254776 DOI 10.17182/hepdata.10167

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.