Formaggio, J.A.
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Production of $\psi$ (3100) and $\psi^{\prime}$ (3700) in p-Be Collisions at 400 GeV

Snyder, H.D. ; Hom, D.C. ; Lederman, L.M. ; et al.
Phys.Rev.Lett. 36 (1976) 1415, 1976.
Inspire Record 108462 DOI 10.17182/hepdata.21117

We report preliminary results on the production of electron-positron pairs in the mass range 2.5 to 4 GeV in 400-GeV p-Be interactions. Production cross sections of the ψ(3100) near x=0 as a function of pt, x, and the decay angle are presented and implications of these new data for single direct leptons are discussed. A ψ′(3700) signal is observed at a level corresponding to σ(ψ′)σ(ψ)=(10±3)%.

1 data table
Table 1

No description provided.


Production of 4 pi+- and 6 pi+- by e+ e- Annihilation Between 2.4-GeV and 7.4-GeV

Jean-Marie, B. ; Abrams, G.S. ; Boyarski, A. ; et al.
SLAC-PUB-1711, 1976.
Inspire Record 108089 DOI 10.17182/hepdata.18658

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Observation of a Resonance at 4.4-GeV and Additional Structure Near 4.1-GeV in e+ e- Annihilation

Siegrist, J. ; Abrams, G.S. ; Boyarski, A. ; et al.
Phys.Rev.Lett. 36 (1976) 700, 1976.
Inspire Record 108144 DOI 10.17182/hepdata.21093

We observe a resonancelike structure in the total cross section for hadron production by e+e− colliding beams at a mass of 4414 ± 7 MeV having a total width Γ=33±10 MeV. From the area under this resonance, we deduce the partial width to electron pairs to be Γee=440±140 eV. Further structure of comparable width is present near 4.1 GeV.

1 data table
Table 1

No description provided.


Omega Production in the Reaction pi- p --> pi+ pi- pi0 n at 8-GeV/c and 12-GeV/c

Dowell, J.D. ; Garvey, J. ; Jobes, M. ; et al.
Nucl.Phys.B 108 (1976) 30-44, 1976.
Inspire Record 100856 DOI 10.17182/hepdata.35781

The reaction π − p → ω n has been studied at 8 and 12 GeV / c incident momenta with the CERN Omega spectrometer using a neutron time of flight trigger. The differential cross sections and the ω-decay density matrix elements are presented as functions of the momentum transfer squared − t in the range of 0.02 to 0.80 GeV 2 . The data are used to evaluate the intercept and slope of both the natural and unnatural parity exchange trajectories. Regge exchange amplitude factorisation tests involving the reaction π N → ω N are investigated.

3 data tables
Table 1

No description provided.

Table 2

'FIT'.

Table 3

'FIT'.


A High Statistics Study of Omega0 Production

The Carleton-Michigan State-Ohio State-Toronto collaboration Shaevitz, M.H. ; Reay, N.W. ; Reibel, K. ; et al.
Phys.Rev.Lett. 36 (1976) 8, 1976.
Inspire Record 2932 DOI 10.17182/hepdata.37234

We report results from a study of π−p→ω0n at 6.0 GeV/c based on 28 000 events from a charged and neutral spectrometer. Background under the ω0 is only 7%, a large improvement over deuterium-bubble-chamber work. Density matrix elements, projected cross sections, and effective trajectories for natural and unnatural exchanges are presented.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Differential Cross-Section for pi- p --> eta0 n at 6.0-GeV/c

The Carleton-Michigan State-Ohio State-Toronto collaboration Shaevitz, M.H. ; Reay, N.W. ; Reibel, K. ; et al.
Phys.Rev.Lett. 36 (1976) 5, 1976.
Inspire Record 2931 DOI 10.17182/hepdata.21104

We have measured the differential cross section for π−p→η0n at 6.0 GeV/c from 6730 very clean events in which the decay η→π+π−π0 was detected. The high statistics reveals a sizable forward turnover, implying a dominance of the helicity-flip amplitude. A precisely determined A2 trajectory, linear for |t|<1.0 (GeV/c)2, is found from combining our data with those at energies up to 101 GeV.

1 data table
Table 1

THE RESOLUTION IN TP IS EVERYWHERE SMALLER THAN THE BIN WIDTH.


A Study of the Line Reversed Hypercharge Exchange Reactions pi+ p --> K+ Sigma+ (1385) and K- p --> pi- Sigma+ (1385) at 10-GeV/c

Berglund, A. ; Buran, T. ; Carlson, P.J. ; et al.
Phys.Lett.B 60 (1975) 117-120, 1975.
Inspire Record 100190 DOI 10.17182/hepdata.27751

We present results on the differential cross-sections for the reactions π + p → K + Σ + (1385) and K − p → π − Σ + (1385) at 10 GeV/ c . For the first time, the same equipment has been used in measuring both reactions, in order to obtain good relative normalization. In the region of low t ( t min to −0.3 (GeV/ c ) 2 ) the two differential cross-sections have similar shape, and show a sharp forward dip indicating a dominant helicity flip contribution. However, the magnitudes of the cross-sections are significantly different, indicating substantial exchange degeneracy breaking. We find the ratio of the integrated cross-sections for the reactions K − p → π − Σ + (1385) and π + p → K + Σ + (1385) over the range −0.3 < t ′ < 0.0 (GeV/ c ) 2 to be 2.0 ± 0.2.

2 data tables
Table 1

TMIN = -0.013 GEV**2.

Table 2

TMIN = +0.012 GEV**2.


Production of the Delta (1950) by One Pion Exchange in pi+ p Interactions at 13-GeV/c

Gaidos, J.A. ; Miller, David Harry ;
Phys.Rev.D 12 (1975) 2565, 1975.
Inspire Record 2181 DOI 10.17182/hepdata.24834

We have observed the production of high-mass I=32 baryon resonances in π+p interactions at 13 GeV/c. The most prominent of these is found to be the F37 Δ(1950). It is produced by one-pion exchange and the data are well described by on-shell π+p phase shifts. Decays into pπ+ and pπ+π0 are observed and the Δ(1950) is found to have a mass 1.880 ± 0.010 GeV and width of 0.180 ± 0.030 GeV with a production cross section of 43 ± 4 μb.

1 data table
Table 1

RESONANCE BACKGROUNDS SUBTRACTED.


Some Features of the Reaction p p --> Delta++ (1236) n at 6-GeV/c

Mountz, J.D. ; Smith, Gerald A. ; Lennox, Arlene J. ; et al.
Phys.Rev.D 12 (1975) 1211, 1975.
Inspire Record 99855 DOI 10.17182/hepdata.24861

Approximately 12 000 examples of the reaction pp→Δ++(1236)n have been identified at 6 GeV / c in a spark-chamber experiment performed at the Argonne National Laboratory Zero Gradient Synchrotron. The experimental invariant-mass and momentum-transfer-squared distributions are in agreement with predictions of the Chew-Low one-pion-exchange model, suitably modified to account for form factors or absorption. The data have been extrapolated from the physical region to the pion pole. It is found that the Dürr-Pilkuhn and Benecke-Dürr models, in conjunction with quadratic extrapolations in t, reproduce the known on-mass-shell dependence of the cross section for the elastic π+p scattering.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Azimuthal Asymmetry in Inclusive Hadron Production by e+ e- Annihilation

Schwitters, R. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 35 (1975) 1320, 1975.
Inspire Record 100683 DOI 10.17182/hepdata.21192

We have observed an azimuthal asymmetry in inclusive hadron production by e+e− annihilation at the center-of-mass energy s=7.4 GeV. The asymmetry is caused by the polarization of the circulating beams in the storage ring and allows separate determination of the transverse and longitudinal structure functions. We find that transverse production dominates for x>0.2 where x is the scaling variable 2ps.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.