Measurement of the Polarization Parameter in 24-GeV/c Proton Proton Elastic Scattering at Small Momentum Transfers

Crabb, D.G. ; Green, K. ; Kyberd, P. ; et al.
Nucl.Phys.B 121 (1977) 231-236, 1977.
Inspire Record 124254 DOI 10.17182/hepdata.35517

A measurement of the polarization parameter P 0 in pp elastic scattering has been made at 24 GeV/ c over the range | t | = 0.1 to 0.9 (GeV/ c ) 2 , positive, falling to zero around | t | = 0.8 (GeV/ c ) 2 . For the range 0.1 ⪕ |t| ⪕ 0.4 GeV /c) 2 , P 0 is constant at about 0.03.

1 data table

Axis error includes +- 5/5 contribution (SYS-ERR DUE MAINLY TO UNCERTAINTY IN KNOWLEDGE OF ABSOLUTE VALUE OF TARGET POLARIZATION).


Omega-Meson Production by Virtual Photons

Joos, P. ; Ladage, A. ; Meyer, H. ; et al.
Nucl.Phys.B 122 (1977) 365-382, 1977.
Inspire Record 118808 DOI 10.17182/hepdata.35453

Qausi-elastic ω production by ep scattering in the kinematic region 0.3. < Q 2 < 1.4 GeV 2 and 1.7 < W < 2.8 GeV was studied using a streamer chamber at DESY. The production angular distribution for γ V p → ω p has a strong non-peripheral component for W < 2 GeV. The ω production cross section falls by a factor of 4 as W changes from 1.7 to 2.8 GeV. In contrast the cross section for ω production with | t | < 0.5 GeV 2 is W independent between 1.7 and 2.8 GeV and for W > 2.0 GeV consistent in both W and Q 2 dependence with the predictions of a model based on one-pion exchange and diffraction.

5 data tables

FOR ALL T-VALUES. THE GAMMA* P TOTAL CROSS SECTION WAS TAKEN FROM A FIT TO THE DATA OF S. STEIN ET AL., PR D12, 1884 (1975). 'PPD'.

'PPD'. PERIPHERAL OMEGA PRODUCTION.

No description provided.

More…

Investigation of (K pi) Mass Enhancement Near 1870-MeV in the Reaction K- p --> K- pi+ n at 10-GeV/c and 16-GeV/c

The Aachen-Berlin-CERN-London-Vienna collaboration Grassler, H. ; Laven, H. ; Otter, G. ; et al.
Nucl.Phys.B 125 (1977) 189, 1977.
Inspire Record 119121 DOI 10.17182/hepdata.35408

An enhancement in the (K − π + ) mass distribution at 1871 ± 10 MeV with full width of 285 ± 40 MeV is observed in the charge-exchange reaction K − p → K − π + n at 10 and 16 GeV/ c . The energy dependence of its cross section, the shape of the differential cross section d σ /d t and the decay angular distributions are consistent with a production mechanism by pion exchange. No significant enhancement at the same mass is seen in the non-charge exchange reaction K − p → (K π ) − p. The experimental evidence is reviewed and it is suggested that there may be more than one K ∗ enhancement in the 1700–1900 mass region.

2 data tables

FOR ALL EVENTS WITH 1.7 < M(K- PI+) < 2 GEV. NO FORWARD DIP. 'THETA CUT'.

THE 14.3 GEV/C POINT IS FROM ANALYSING THE DATA OF M. SPIRO ET AL., PL 60B, 389 (1976) IN THE SAME WAY. 'THETA-CUT'.


Amplitudes and Exchange Mechanisms for K* Resonances Produced by the Reactions K+- p --> K*+- p at 10-GeV/c

Baldi, R. ; Bohringer, T. ; Dorsaz, P.A. ; et al.
Phys.Lett.B 70 (1977) 377-382, 1977.
Inspire Record 126179 DOI 10.17182/hepdata.27517

We compare production of the low mass K π -resonances by K + and K − beams in the non-charge-exchange reactions K ± p → K 0 s π ± p at 10 GeV/ c . High statistics data, obtained with the same apparatus, allow extraction of the K ∗ (890) and K ∗ (1420) production amplitudes corresponding to unnatural and natural parity exchange in the t -channel. The NPE-part dominates in both charge states. Its t -dependence shows a strong crossover at t ≈ −0.3 (GeV/ c ) 2 for the K ∗ (1420). For the K ∗ (890) the crossover is weaker but it occurs at the same value of t . This behaviour can be explained by pomeron, f and ω Regge exchange contributions to the NPE amplitude. The UPE amplitudes agree, both in normalisation and t -dependence, with the expectations of π and B exchange as isolated from data for the charge exchange reaction K − p → (K − π + )n.

1 data table

No description provided.


Momentum Analysis of Kaon and Pion Pairs Produced from Timelike Photons at 1.6-GeV Energy

Esposito, B. ; Felicetti, F. ; Marini, A. ; et al.
Phys.Lett.B 67 (1977) 239-242, 1977.
Inspire Record 124109 DOI 10.17182/hepdata.27574

We present results for the total cross section of e + e − annihilation into two hadrons at 1.6 GeV: σ ππ = σ KK = (1.8 ± 1.1) × 10 -33 cm 2 .From these values we obtain the time-like electromagnetic form factors these mesons: | F π | 2 = 0.24 ± 0.14 and | F K | 2 = 0.46 ± 0.26.

1 data table

No description provided.


Study of the Reaction d (p, pi+) t at t(p) = 410-MeV, 605-MeV and 809-MeV

Aslanides, E. ; Bertini, R. ; Bing, O. ; et al.
Phys.Rev.Lett. 39 (1977) 1654-1656, 1977.
Inspire Record 126515 DOI 10.17182/hepdata.20981

Pion production on a CD2 target has been measured using the high-resolution magnetic spectrometer SPES I. Differential cross sections for the reaction D(p, π+)T have been determed at Tp=410, 605, and 809 MeV. The present data, together with previous results establish a complete angular distribution of the reaction D(p, π+)T at ∼ 600 MeV and the energy dependence of the differential cross section for this reaction at several constant momentum transfers.

2 data tables

No description provided.

No description provided.


Photoproduction of rho0 and rho- Mesons at 3-GeV

Bapu, P. ; Endorf, R. ; Meadows, B. ; et al.
Phys.Rev.D 15 (1977) 26, 1977.
Inspire Record 123802 DOI 10.17182/hepdata.24621

The photoproduction of ρ0 and ρ− mesons has been studied at 3 GeV in the reactions γd→dπ±π−, γd→psnπ+π−, and γd→pspπ−π0. For ρ0 and ρ− production in these reactions we present the total and differential cross sections, the decay angular distributions, and the spin density matrix elements. The photoproduction of the ρ0 is found to be consistent with s-channel helicity conservation and is dominated by natural-parity exchange. The ρ− meson production has approximately equal natural- and unnatural-parity-exchange contributions. The unnatural-parity-exchange contribution is consistent with one-pion exchange and is used to estimate the value of Γρπγ.

6 data tables

No description provided.

No description provided.

No description provided.

More…

Search for xi* Production in K- p Interactions at 2.87-GeV/c

Briefel, E. ; Gourevitch, S.A. ; Kirsch, L. ; et al.
Phys.Rev.D 16 (1977) 2706, 1977.
Inspire Record 118843 DOI 10.17182/hepdata.24494

Evidence is presented for production of Ξ* resonances, decaying into Ξπ, Ξ(1530)π, ΛK¯, and ΣK¯, in K−p interactions at 2.87 Gev/c. The data represent final combined results from a 30-events/μb hydrogen exposure and an 18-events/μb exposure in deuterium designed to study Ξ* production in the mass interval 1.46-2.07 GeV/c2. In addition to Ξ(1820) and Ξ(1940), signals have been observed at masses of 1630 MeV/c2 and 1860 MeV/c2 decaying into Ξ−π+ and YK¯, respectively. Reaction cross sections have been measured for all final states containing two visible signs of strangeness, and for the final states ΛK−K+ and Σ0K−K+.

4 data tables

CROSS SECTIONS ARISING FROM VARIOUS TOPOLOGIES.

K- P CROSS SECTIONS FROM DEUTERIUM TARGET EXPERIMENT. RESULTS ARE IN GOOD AGREEMENT WITH THE HYDROGEN DATA.

No description provided.

More…

Simultaneous Measurement of the Spin Parameters p and c(n n) in p p Elastic Scattering at 2, 3, 4, and 6-GeV/c

Miller, D. ; Wilson, C. ; Giese, R. ; et al.
Phys.Rev.D 16 (1977) 2016-2026, 1977.
Inspire Record 126510 DOI 10.17182/hepdata.24496

Using the polarized-beam facility at Argonne National Laboratory and a polarized proton target, simultaneous measurements of the spin parameter P and the spin correlation term CNN were made. Data were obtained and analyzed at beam momenta of 2, 3, 4, and 6 GeV/c in the momentum-transfer-squared interval 0.1≤|t|≤2.8 (GeV/c)2. A preliminary phase-shift analysis of the 2- and 3-GeV/c data is discussed and a comparison with predictions of a particular Regge-pole model at all four energies is made.

4 data tables

No description provided.

No description provided.

No description provided.

More…

He-3 Production in He-4 Fragmentation on Protons at 6.85-GeV/c

Bizard, G. ; Le Brun, C. ; Berger, J. ; et al.
Nucl.Phys.A 285 (1977) 461-468, 1977.
Inspire Record 125054 DOI 10.17182/hepdata.37099

The angular distribution of the inclusive reaction 4 He + p → 3 He + X was measured with 6.85 GeV/ c incident alphas. At large angles, the observed kinematics corresponds to the elastic scattering on the target proton of an 3 He present in the incoming 4 He, the remaining neutron being a spectator. This shows the presence of an important component of 3 He in 4 He. The integrated cross section for 3 He production is σ 3He = 24.1 ± 1.9 mb.

1 data table

No description provided.