Briere, Roy A.
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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 (?////).


Neutron production in coincidence with fragments from the 40Ca + H reaction at Elab = 357A and 565A MeV

Tuve, C. ; Albergo, S. ; Boemi, D. ; et al.
Phys.Rev.C 59 (1999) 233-238, 1999.
Inspire Record 493470 DOI 10.17182/hepdata.25641

Neutron production, in coincidence with fragments emitted in the 40Ca+H reaction at Elab=357A and 565A MeV, has been measured using a 3-module version of the multifunctional neutron spectrometer MUFFINS. The mean neutron multiplicities for neutrons detected in the angular range covered by MUFFINS (0°−3.2°) have been estimated from the comparison between the neutron cross sections, in coincidence with the fragments, and the elemental cross sections. We have found evidence for a preequilibrium emission of prompt neutrons in superposition to a “slower” deexcitation of the equilibrated remnant by emission of nucleons and fragments, as already seen in inclusive rapidity distributions. The energy dependence of the inclusive neutron production cross sections, measured in a previous work, is here interpreted as due to the stronger neutron focusing in the forward direction at the higher energy. Comparison with a BNV+phase space coalescence model is discussed.

1 data table
Table 1

No description provided.


Pion proton integral cross sections at T(pi) = 40-MeV to 284-MeV.

Kriss, B.J. ; Hoibraten, S. ; Holcomb, M.D. ; et al.
Phys.Rev.C 59 (1999) 1480-1487, 1999.
Inspire Record 500165 DOI 10.17182/hepdata.25638

Integral cross sections for the scattering of pions by protons into angles greater than 30° (lab) have been measured at a wide range of energies spanning the delta resonance using liquid hydrogen targets. Cross sections were measured for π+p scattering at 40 energies from 39.8 to 283.9 MeV and for π−p at 15 energies from 80.0 to 283.9 MeV. Comparisons with phase shift predictions from the Karlsruhe group show good agreement on resonance but significant deviations below 100 MeV.

2 data tables
Table 1

The uncertainties shown include statistical and systematic contributions.

Table 2

The uncertainties shown include statistical and systematic contributions.


Strong absorption radii from reaction cross-section measurements for neutron-rich nuclei

Aissaoui, N. ; Added, N. ; Carlin, N. ; et al.
Phys.Rev.C 60 (1999) 034614, 1999.
Inspire Record 506171 DOI 10.17182/hepdata.25461

Energy-integrated reaction cross sections have been measured at energies ranging from 38 to 80 MeV/nucleon for various exotic neutron-rich isotopes of Al, Si, P, S, Cl, Ar, K, Ca, Sc, and Ti stopping in Si. An experimental technique is employed where Si detectors are used for both particle identification and to serve as the target material. The reduced strong absorption radii r02 are deduced and compared with other experimental results. The radius dependence on the neutron number was studied and a trend of increasing reduced radius with neutron excess was found. This behavior is similar to that seen in lighter systems, although less pronounced than found there. The implications of this result on the conjectured existence of neutron halo or skin nuclei is discussed.

49 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Angular dependence of the pp elastic-scattering analyzing power between 0.8 and 2.8 GeV. II. Results for higher energies

Allgower, C.E. ; Ball, J. ; Beddo, M.E. ; et al.
Phys.Rev.C 60 (1999) 054002, 1999.
Inspire Record 508562 DOI 10.17182/hepdata.25565

Measurements at 18 beam kinetic energies between 1975 and 2795 MeV and at 795 MeV are reported for the pp elastic-scattering single spin parameter Aooon=Aoono=AN=P. The c.m. angular range is typically 60–100°. These results are compared to previous data from Saturne II and other accelerators. A search for energy-dependent structure at fixed c.m. angles is performed, but no rapid changes are observed.

20 data tables
Table 1

Measured values of the P P analysing power at kinetic energy 0.795 GeV. Therelative and additive systematic errors are +- 0.018 and 0.0007.

Table 2

Measured values of the P P analysing power at kinetic energy 1.975 GeV. Therelative and additive systematic errors are +- 0.045 and 0.002.

Table 3

Measured values of the P P analysing power at kinetic energy 2.035 GeV fromrun I. The relative and additive systematic errors are +- 0.044 and 0.002.

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Angular dependence of the p p elastic scattering analyzing power between 0.8-GeV and 2.8-GeV. 1. Results for 1.80-GeV to 2.24-GeV

Allgower, C.E. ; Ball, J. ; Barabash, L.S. ; et al.
Phys.Rev.C 60 (1999) 054001, 1999.
Inspire Record 508563 DOI 10.17182/hepdata.25566

Experimental results are presented for the pp elastic-scattering single spin observable Aoono=Aooon=AN=P, or the analyzing power, at 19 beam kinetic energies between 1795 and 2235 MeV. The typical c.m. angular range is 60–100°. The measurements were performed at Saturne II with a vertically polarized beam and target (transverse to the beam direction and scattering plane), a magnetic spectrometer and a recoil detector, both instrumented with multiwire proportional chambers, and beam polarimeters.

21 data tables
Table 1

Measurement values of the P P analysing power at kinetic energy 1.795 GeV. The relative and additive systematic errors are +- 0.106 and 0.003.

Table 2

Measurement values of the P P analysing power at kinetic energy 1.845 GeV. The relative and additive systematic errors are +- 0.068 and 0.001.

Table 3

Measurement values of the P P analysing power at kinetic energy 1.935 GeV. The relative and additive systematic errors are +- 0.091 and 0.003.

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Measurement of the proton and deuteron spin structure functions g2 and asymmetry A(2).

The E155 collaboration Anthony, P.L. ; Arnold, R.G. ; Averett, T. ; et al.
Phys.Lett.B 458 (1999) 529-535, 1999.
Inspire Record 493768 DOI 10.17182/hepdata.27072

We have measured the spin structure functions g2p and g2d and the virtual photon asymmetries A2p and A2d over the kinematic range 0.02 < x < 0.8 and 1.0 < Q^2 < 30(GeV/c)^2 by scattering 38.8 GeV longitudinally polarized electrons from transversely polarized NH3 and 6LiD targets.The absolute value of A2 is significantly smaller than the sqrt{R} positivity limit over the measured range, while g2 is consistent with the twist-2 Wandzura-Wilczek calculation. We obtain results for the twist-3 reduced matrix elements d2p, d2d and d2n. The Burkhardt-Cottingham sum rule integral - int(g2(x)dx) is reported for the range 0.02 < x < 0.8.

4 data tables
Table 1

2.75 degree spectrometer data.

Table 2

5.5 degree spectrometer data.

Table 3

10.5 degree spectrometer data.

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Measurement of gamma p --> K0 Sigma+ at photon energies up to 1.55-GeV.

The SAPHIR collaboration Goers, S ; Barth, J ; Bennhold, C ; et al.
Phys.Lett.B 464 (1999) 331-338, 1999.
Inspire Record 512574 DOI 10.17182/hepdata.27045

The reaction γp → K 0 Σ + has been measured with the SAPHIR detector at the electron stretcher ring ELSA. The total cross section rises up to a peak value of 1.1 μ b at a photon energy of 1.4 GeV. The differential cross sections dσ/dΩ are consistent with being flat throughout the measured energy range. The first measurement of the Σ + polarization in photon induced reactions was obtained.

3 data tables
Table 1

Total cross section for the reaction GAMMA P --> K0 SIGMA+. Errors include statistics and the uncertainty on the acceptance calculation and photon flux.

Table 2

Differential cross section for the reaction GAMMA P --> K0 SIGMA+. Errors are dominated by statistical uncertainties.

Table 3

Measure of SIGMA+ polarization in the reaction GAMMA P --> K0 SIGMA+.


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.


First observation of Sigma- e- elastic scattering in the hyperon beam experiment WA89 at CERN.

The WA89 collaboration Adamovich, M.I. ; Aleksandrov, Yu.A. ; Barberis, D. ; et al.
Eur.Phys.J.C 8 (1999) 59-66, 1999.
Inspire Record 500379 DOI 10.17182/hepdata.43061

We have investigated the elastic scattering of high energy $\Sigma^-$ off electrons from carbon and copper targets using the CERN hyperon beam. Scattering events a

1 data table
Table 1

No description provided.