Date

EXCLUSIVE PRODUCTION OF PROTON - ANTI-PROTON PAIRS IN TWO PHOTON COLLISIONS AT PEP

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 36 (1987) 3506, 1987.
Inspire Record 246557 DOI 10.17182/hepdata.23356

We report cross sections for the process γγ→pp¯ at center-of-mass energies W from 2.0 to 2.8 GeV. These results have been extracted from measurements of e+e−→e+e−pp¯ at an overall center-of-mass energy of 29 GeV, using the TPC/Two-Gamma facility at the SLAC storage ring PEP. Cross sections for the untagged mode [both photons nearly real] are shown to lie well above QCD predictions. Results are also presented for the single-tagged mode [one photon in the range 0.16

3 data tables

Data read from graph in preprint. Statistical errors only.

Data read from graph. Statistical errors only.

Data read from graph. Statistical errors only.


Production of $G(1590)$ in 300-{GeV} Central $\pi^- N$ Collisions

The Serpukhov-Brussels-Los Alamos-Annecy(LAPP)-Pisa collaboration Alde, D. ; Bellazzini, R. ; Binon, F.G. ; et al.
Phys.Lett.B 201 (1988) 160, 1988.
Inspire Record 250393 DOI 10.17182/hepdata.6493

Significant production of G(1590), a scalar glueball candidate, is observed in a study of η pairs produced in π−N central collisions at 300 GeV/ c .

2 data tables

No description provided.

No description provided.


A(ll) at Small Momentum Transfers for the First Complete Determination of the Forward $p p$ Scattering Amplitude

Pauletta, G. ; Gazzaly, M. ; Tanaka, N. ; et al.
Phys.Lett.B 211 (1988) 19-23, 1988.
Inspire Record 252973 DOI 10.17182/hepdata.29911

The asymmetry A LL for pp elastic scattering has been measured at 650 and 800 MeV in the region of Coulomb-nuclear interference. The real part of the double-spin-flip amplitude extracted from these data completes our determination of the forward pp scattering amplitudes at these energies. Comparison with the predictions of forward dispersion relations reveals a discrepancy in the spin-dependent channels at 650 MeV.

2 data tables

No description provided.

No description provided.


Production of Four Prong Final States in Photon-photon Collisions

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 37 (1988) 28, 1988.
Inspire Record 261630 DOI 10.17182/hepdata.3824

Results are presented on the exclusive production of four-prong final states in photon-photon collisions from the TPC/Two-Gamma detector at the SLAC e+e− storage ring PEP. Measurement of dE/dx and momentum in the time-projection chamber (TPC) provides identification of the final states 2π+2π−, K+K−π+π−, and 2K+2K−. For two quasireal incident photons, both the 2π+2π− and K+K−π+π− cross sections show a steep rise from threshold to a peak value, followed by a decrease at higher mass. Cross sections for the production of the final states ρ0ρ0, ρ0π+π−, and φπ+π− are presented, together with upper limits for φρ0, φφ, and K*0K¯ *0. The ρ0ρ0 contribution dominates the four-pion cross section at low masses, but falls to nearly zero above 2 GeV. Such behavior is inconsistent with expectations from vector dominance but can be accommodated by four-quark resonance models or by t-channel factorization. Angular distributions for the part of the data dominated by ρ0ρ0 final states are consistent with the production of JP=2+ or 0+ resonances but also with isotropic (nonresonant) production. When one of the virtual photons has mass (mγ2=-Q2≠0), the four-pion cross section is still dominated by ρ0ρ0 at low final-state masses Wγγ and by 2π+2π− at higher mass. Further, the dependence of the cross section on Q2 becomes increasingly flat as Wγγ increases.

12 data tables

UNTAGGED DATA.

TAGGED DATA, RESULTS OBTAINED USING TRANSVERSE-TRANSVERSE LUMINOSITY ONLY. DATA FOR Q2=0 ARE FROM UNTAGGED SAMPLE, ERRORS DUE TO RELATIVE NORMALISATION OF THESE SAMPLES IS INCLUDED INTO ERRORS QUOTED.

UNTAGGED DATA.

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Measurement of Analyzing Power and Spin Correlations in $N P$ Elastic Scattering at 0.744-{GeV} and 0.794-{GeV} Using a Deuteron Polarized Beam

De Lesquen, A. ; Lehar, F. ; Van Rossum, L. ; et al.
Nucl.Phys.B 304 (1988) 673-686, 1988.
Inspire Record 268253 DOI 10.17182/hepdata.33258

The np and the pp analyzing powers A oono d and spin correlations A oonn d and A oosk d were measured simultaneously using the SATURNE II polarized deuteron beam at 0.744 and 0.794 GeV/nucleon. The results for the pp observables coincide with the free pp elastic scattering data. We thus can assume that also the np analyzing power A oono d and spin correlations A oonn d and A oosk d are equal to those for scattering of free polarized neutrons. The np data cover the angular region 95°⩽ θ CM ⩽122°. Our results for A oono d (np) confirm the phase-shift analysis predictions but spin correlations A oonn d (np) and A oosk d (np) have never been measured in this energy region and will considerably affect the PSA solution. Present results allow conclusions about the angular dependence near the minimum of A oono (np) and A oonn (np) in the vicinity of 0.8 GeV.

12 data tables

No description provided.

No description provided.

No description provided.

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High Transverse Momentum Hadron Hadron Correlations in $\sqrt{s}=38$.8 GeV Proton Proton Interactions

Jaffe, D.E. ; Straub, P.B. ; Adams, M.R. ; et al.
Phys.Rev.D 38 (1988) 1016-1019, 1988.
Inspire Record 268868 DOI 10.17182/hepdata.23278

Measurements of correlations of nearly back-to-back hadrons produced at a large transverse momentum in s=38.8 GeV proton-proton collisions are presented and compared to previous results with a beryllium target. The correlations of identified unlike-sign hadron pairs in ratio to the correlation for all unlike-sign pairs are compared with predictions of the Lund model. These predictions differ from the data.

1 data table

No description provided.


Measurement of b, the Nuclear Slope Parameter of the p anti-p Elastic Scattering Distribution at s**(1/2) = 1800-GeV

The E710 collaboration Amos, N.A. ; Baker, W.F. ; Bertani, M. ; et al.
Phys.Rev.Lett. 61 (1988) 525, 1988.
Inspire Record 261411 DOI 10.17182/hepdata.20066

We have studied proton-antiproton elastic scattering at s=1800 GeV at the Fermilab Collider, in the range 0.02<|t|<0.13 (GeV/c)2. Fitting the distribution by exp(−B|t|), we obtain a value of B of 17.2±1.3 (GeV/c)−2.

2 data tables

No description provided.

Error contains estimate of systematic effects.


Charged Particle Production in $K^+ p$, $\pi^+ p$ and $p p$ Interactions at 250-{GeV}/$c$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Ataian, M.R. ; et al.
Z.Phys.C 39 (1988) 311-329, 1988.
Inspire Record 265504 DOI 10.17182/hepdata.15620

None

6 data tables

No description provided.

No description provided.

No description provided.

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Evidence for Iota (1460) Production in $\pi^- p$ Interactions at 21.4-{GeV}/$c$

Rath, M.G. ; Cason, N.M. ; Bensinger, J.R. ; et al.
Phys.Rev.Lett. 61 (1988) 802, 1988.
Inspire Record 262921 DOI 10.17182/hepdata.20086

The KS0KS0π0 system has been studied in the exclusive reaction π−p→KS0KS0π0n at 21.4 GeV/c. Evidence for the production of the f1(1285) and the η(1460) is presented. The η(1460) is produced away from minimum momentum transfer in the presence of nonresonant K*K (S-wave) production and phase-space background. The observed mass, width, and decay properties of the η(1460) are consistent with those attributed to the ι(1460) observed in radiative Jψ decay.

1 data table

No description provided.


Dimuon Production in 800 GeV Proton Nucleus Collisions

Brown, C.N. ; Cooper, W.E. ; Finley, D. ; et al.
Phys.Rev.Lett. 63 (1989) 2637-2640, 1989.
Inspire Record 288346 DOI 10.17182/hepdata.20031

A measurement of continuum dimuon production in proton-copper collisions at 800-GeV incident energy is presented. The dimuons observed in this experiment cover the mass range from 6.5 to 18 GeV near y=0 in the proton-nucleon center-of-momentum frame. Scaling forms of the cross section for the continuum are compared with the results of other experiments in the context of the parton model and quantum chromodynamics. The present limitations of such scaling comparisons are discussed.

1 data table

No description provided.