Proton-proton interactions at 5.3 BeV

Wright, Robert W. ; Saphir, George ; Powell, Wilson M. ; et al.
Phys.Rev. 100 (1955) 1802, 1955.
Inspire Record 1188071 DOI 10.17182/hepdata.26941

None

1 data table

No description provided.


EXCITATION OF THE 15.1-MeV AND 16.1-MeV LEVELS OF THE C-12 NUCLEUS BY ELECTRON SCATTERING

Dudelzak, B. ; Taylor, R.E. ;
J.Phys.Radium 22 (1961) 544, 1961.
Inspire Record 16520 DOI 10.17182/hepdata.37717

None

6 data tables

No description provided.

No description provided.

No description provided.

More…

Polarization in pi--p Scattering between 500 and 940 Mev

Beall, E.F. ; Cork, B. ; Murphy, P.G. ; et al.
Phys.Rev. 126 (1962) 1554-1560, 1962.
Inspire Record 944982 DOI 10.17182/hepdata.26812

A graphite-plate spark chamber has been used to analyze the polarization of protons recoiling from π−−p scattering. The observations were made at 90° (c.m. system) pion scattering angle for seven incident pion energies between 500 and 940 Mev, at 120° or 135° for five energies in this interval, and also at 75° for 500 Mev only. The results are compared with predictions of several models used to explain the maxima in the π−−p scattering cross section. Qualitative arguments show that the energy intervals between these maxima are not completely dominated by neighboring single-state resonances. Phase shifts found to be large in scattering also seem to be large in polarization.

10 data tables

No description provided.

No description provided.

No description provided.

More…

The $\pi^- p$ reaction around the $\Lambda^0 K^0$ threshold

Crittenden, R.R. ; Martin, H.J. ; Musgrave, B. ;
116-123, 1963.
Inspire Record 1407768 DOI 10.17182/hepdata.70311

None

1 data table

No description provided.


$\{pi}-p$ interactions at 1.59 GeV/c

Alitti, J. ; Baton, J.P. ; Berthelot, A. ; et al.
Nuovo Cim. 29 (1963) 515, 1963.
Inspire Record 851185 DOI 10.17182/hepdata.980

Report on the investigation of interactions in π−p collisions at a pion momentum of 1.59 GeV/c, by means of the 50 cm Saclay liquid hydrogen bubble chamber, operating in a magnetic field of 17.5 kG. The results obtained concern essentially the elastic scattering and the inelastic scattering accompanied by the production of either a single pion in π−p→ pπ−π0 and nπ−π+ interactions, or by more than one pion in four-prong events. The observed angular distribution for the elastic scattering in the diffraction region, can be approximated by an exponential law. From the extrapolated value, thus obtained for the forward scattering, one gets σel= (9.65±0.30) mb. Effective mass spectra of π−π0 and π−π+ dipions are given in case of one-pion production. Each of them exhibits the corresponding ρ− or ρ0 resonances in the region of ∼ 29μ2 (μ = mass of the charged pion). The ρ peaks are particularly conspicuous for low momentum transfer (Δ2) events. The ρ0 distribution presents a secondary peak at ∼31μ2 due probably to the ω0 → π−π+ process. The branching ratio (ω0→ π+π−)/(ω0→ π+π− 0) is estimated to be ∼ 7%. The results are fairly well interpreted in the frame of the peripheral interaction according to the one-pion exchange (OPE) model, Up to values of Δ2/μ2∼10. In particular, the ratio ρ−/ρ0 is of the order of 0.5, as predicted by this model. Furthermore, the distribution of the Treiman-Yang angle is compatible with an isotropic one inside the ρ. peak. The distribution of\(\sigma _{\pi ^ + \pi ^ - } \), as calculated by the use of the Chew-Low formula assumed to be valid in the physical region of Δ2, gives a maximum which is appreciably lower than the value of\(12\pi \tilde \lambda ^2 = 120 mb\) expected for a resonant elastic ππ scattering in a J=1 state at the peak of the ρ. However, a correcting factor to the Chew-Low formula, introduced by Selleri, gives a fairly good agreement with the expected value. Another distribution, namely the Δ2 distribution, at least for Δ2 < 10 μ2, agrees quite well with the peripheral character of the interaction involving the ρ resonance. π− angular distributions in the rest frame of the ρ exhibit a different behaviour for the ρ− and for the ρ0. Whereas the first one is symmetrical, as was already reported in a previous paper, the latter shows a clear forward π− asymmetry. The main features of the four-prong results are: 1) the occurrence of the 3/2 3/2 (ρπ+) isobar in π−p → pπ+π−π− events and 2) the possible production of the ω0→ π+π−π0 resonance in π−p→ pπ−π+π−π0 events. No ρ’s were observed in four-prong events.

4 data tables

No description provided.

No description provided.

No description provided.

More…

A_1 and A_2 Resonances in pi- p Interactions at 2.75 GeV/c

Alitti, J. ; Baton, J.P. ; Deler, B. ; et al.
Phys.Lett. 15 (1965) 69, 1965.
Inspire Record 49807 DOI 10.17182/hepdata.30488

None

1 data table

No description provided.


pi+ proton, pi- proton and pp elastic scattering at 8.5, 12.4 and 18.4 GeV/c

Harting, D. ; Blackall, P. ; Elsner, B. ; et al.
Nuovo Cim. 38 (1965) 60, 1965.
Inspire Record 49759 DOI 10.17182/hepdata.1110

Approximately 60 000 events have been collected in a spark chamber experiment at the CERN Proton Synchrotron which studied elastic diffraction scattering of π--p and p-p at incident momenta of 8.5, 12.4 and 18.4 GeV/c and of π+-p at 8.5 and 12.4 GeV/c. Magnetic analysis of the incoming and diffraction scattered particle, together with measurement of all angles, permitted each event to be determined as elastic subject to three constraints, so that the inelastic background was rejected with. high efficiency, even at the larger momentum, transfers. Much of the data have been processed by the CERN Automatic Flying-Spot DigitizerHPD. A detailed description of the experimental technique and of the methods of analysis is given. The results, together with data from lower energies, confirm the remarkable energy-independence of the shape of the pion-proton diffraction scattering peak up to |t| = 1.5 (GeV/c)2, wheret is the square of the four-momentum transfer, over a range of pion energies from 2 to 18 GeV. Proton-proton scattering does however appear to show a shrinking diffraction peak. In general, the data agree with other experiments using both counter and bubble chamber techniques, but some differences do appear. During the experiment, data were taken which set an upper limit of 2·102 μb/(GeV/c)2 on the differential elastic cross-section dσ/dt over a range of |t| from 20.9 to 23.4 (GeV/c)2 at 13.4 GeV/c incident pion momentum.

18 data tables

'1'. '2'. '3'. '4'.

More…

Further Evidence for a Possible I=52 N* Resonance at 1580 MeV

Alexander, G. ; Benary, O. ; Reuter, B. ; et al.
Phys.Rev.Lett. 15 (1965) 207-210, 1965.
Inspire Record 944924 DOI 10.17182/hepdata.21831

None

1 data table

Axis error includes +- 0.0/0.0 contribution (?////Not given).


Structure Within the R(1675) Boson and Possible Structure within the A_2(1290)

The CERN Missing Mass Spect. collaboration Levrat, B. ; Tolstrup, C.A. ; Nef, C. ;
Phys.Lett. 22 (1966) 714-718, 1966.
Inspire Record 50977 DOI 10.17182/hepdata.29839

Three narrow peaks with masses 1632 ± 15, 1700 ± 15 and 1748 ± 15, reffered to as R 1 , R 2 and R 3 , have been observed in missing-mass spectrometer runs at incident pion momenta of 7 and 12 GeV/ c and a mass-resolution of ± 15 MeV. One-peak hypothesis gives a confidence level P ( χ 2 )=0.8%; the three-peak one gives P ( χ 2 )=60%. Statistical significance for R 1 , R 2 and R 3 is, respectively, 3.8, 6.6 and 6.1 standard deviations from the highest background line. R 1 and R 2 decay into one and three, while the R 3 decays mainly into three charged particles. Their physical widths are compatible with zero, with upper limits of the order of Γ ⩽30 MeV.

1 data table

No description provided.


K+ P ELASTIC SCATTERING AT 3.5-GeV/c AND 5.0-GeV/c

De Baere, W. ; Debaisieux, J. ; Dufour, J.P. ; et al.
Nuovo Cim.A 45 (1966) 885, 1966.
Inspire Record 50048 DOI 10.17182/hepdata.37572

The elastic scattering of K+ mesons on protons is studied at 3.5 and 5 GeV/c. The total elastic cross-sections are found to be (4.36±0.36) mb and (3.82±0.41) mb respectively. The differential elastic cross-sections, which exhibit characteristic diffraction peaks, are fitted by dσ/dt=(dσ/dt)0eαt, giving α=(3.85±0.12) and (4.70±0.21) (GeV/c)−2 for the two momenta respectively, with |t|⪝0.65 (GeV/c)2. The results are compared to those at neighbouring energies, giving some support to the presence of a real part of the forward scattering amplitude. The diffraction peak shows definite shrinking with increasing momenta. The data are examined in the light of models for high-energy scattering.

1 data table

No description provided.