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
1 data table

No description provided.


Elastic-Differential Cross Section of pi++p at 1.5, 2.0, and 2.5 BeV/c

Cook, Victor ; Cork, Bruce ; Holley, William R. ; et al.
Phys.Rev. 130 (1963) 762-765, 1963.
Inspire Record 944975 DOI 10.17182/hepdata.599

We measured elastic-scattering angular distributions for π++p scattering at 1.5, 2.0, and 2.5 BeV/c using spark chambers to detect scattered pions and protons. A bump that decreases in amplitude with increasing momentum is observed in the backward hemisphere in the 1.5- and 2.0-BeV/c distributions, but is not observed in the 2.5-BeV/c distributions. It appears reasonable to attribute this phenomenon to the 1.45-BeV/c resonance observed in the π++p total cross section. The data are compared with π−+p data and are found to support the theoretical prediction that the scattering cross sections for both charge states should become equal at high energies. We fit the angular distributions with a power series in cosθ*, and compare the extrapolated values for the scattering cross section in the backward direction with the calculation of the neutron-exchange pole contribution to the cross section. The "elementary" neutron-pole term contribution is calculated to be 90 mb/sr at 2.0 BeV/c, in violent disagreement with the extrapolated value, ≈0.5 mb/sr.

4 data tables

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Elastic Scattering of Gamma Rays by Protons

Stiening, R.F. ; Loh, E. ; Deutsch, Martin ;
Phys.Rev.Lett. 10 (1963) 536-537, 1963.
Inspire Record 46876 DOI 10.17182/hepdata.21849
1 data table

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LARGE ANGLE pi- p ELASTIC SCATTERING AT 3.63-GeV/c.

Perl, Martin L. ; Lee, Yong Yung ; Marquit, Erwin ;
Phys.Rev. 138 (1965) B707-711, 1965.
Inspire Record 98 DOI 10.17182/hepdata.26685

The differential cross section for elastic scattering of 3.63−GeVc π− mesons on protons was studied with a hydrogen bubble chamber, the emphasis being on large-angle scattering. From 90 to 180° in the barycentric system, the cross section is roughly flat with an average value of 2.7±1.0 μb/sr. Near and at 180°, there may be a slight peak of magnitude 10±6 μb/sr. But if such a peak exists, it is only one-third to one-fourth the size of the 180° peak found in 4.0 GeVc π++p elastic scattering. In addition to comparison with other π−+p and π++p large-angle elastic-scattering measurements, this measurement is compared with large-angle p+p elastic scattering. In the forward hemisphere a small peak or a plateau exists at cos θ*=+0.60. This appears to be a second diffraction maximum such as has been found in lower-energy π+p elastic scattering. A survey of indications of such a second diffraction maximum in other π+p measurements shows that it always occurs in the vicinity of −t=1.2 (GeVc)2, where t is the square of the four-momentum transfer. As the incident momentum increases, the relative size of this second maximum decreases.

2 data tables

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$\pi^+p$ interactions at $T_\pi = 781$ MeV

Tilger, C.A. ; Poirier, C.P. ; Alyea, E.D., Jr. ; et al.
Phys.Rev. 142 (1966) 972-976, 1966.
Inspire Record 944956 DOI 10.17182/hepdata.26684

Interactions of 781-MeV π+ mesons with protons were investigated using the Brookhaven National Laboratory 14-in. hydrogen bubble chamber. A total of 2305 events was observed. The data were normalized to a total cross section of 22.2 mb, giving partial cross sections σ(π+p→π+p)=9.5±0.5 mb, σ(π+p→π+pπ0)=9.3±0.5 mb, σ(π+p→π+π+n)=2.15±0.17 mb, and a multiple-pion-production cross section of 1.15±0.17 mb. The elastic angular distribution was obtained and is dσdω=(0.25±0.03)+(0.90±0.11)cosθc.m.+(2.57±0.24)cos2θc.m.+(0.19±0.22)cos3θc.m.−(1.73±0.34)cos4c.m.. The kinetic-energy and angular distributions of the outgoing particles in single-pion production are given. The data are compared with other experiments in this energy region and their relevance to the shoulder in the π+p total cross section near 830 MeV is discussed.

1 data table

NEUTRON PROTON ELASTIC SCATTERING FROM 1-GeV TO 6-GeV

Kreisler, M. ; Martin, F. ; Perl, Martin L. ; et al.
Phys.Rev.Lett. 16 (1966) 1217-1220, 1966.
Inspire Record 49861 DOI 10.17182/hepdata.3557
5 data tables

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pi-p Interactions at 460 MeV

Poirier, C.P. ; Tilger, C.A. ; Alyea, E.D. ; et al.
Phys.Rev. 148 (1966) 1311-1314, 1966.
Inspire Record 50913 DOI 10.17182/hepdata.26590

A total of 1589 two-prong events were observed in an exposure of the Brookhaven National Laboratory 14-in. bubble chamber at the Cosmotron. The fit to the elastic angular distribution requires terms through cos4θc.m.. The ratio of the inelastic cross sections σ(π−p→π−π+n)σ(π−p→π−π0p) is 3.75±0.46. The π−p→π−π+n reaction is dominated by formation of the π−n isobar and an enhancement in the di-pion mass spectrum previously reported by Kirz. The π−p→π−π0p reaction shows no structure in the effective-mass spectra.

1 data table

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A COMPARISON OF ELECTRON - PROTON AND POSITRON - PROTON ELASTIC SCATTERING AT FOUR MOMENTUM TRANSFERS UP TO 5.0-GeV/c**2

Mar, J. ; Barish, Barry C. ; Pine, Jerome ; et al.
Phys.Rev.Lett. 21 (1968) 482-484, 1968.
Inspire Record 52726 DOI 10.17182/hepdata.21724

Measurements of the ratio (R) of positron-proton and electron-proton elastic-scattering cross sections have been made, with the square of the four-momentum transfer (q2) equal to 0.20, 0.69, 0.73, 1.54, 2.44, 3.27, 3.79, and 5.00 (GeV/c)2. The measurements, after radiative corrections, are consistent with R=1, with standard errors ranging from ±0.016 to ±0.123. The results give limits for the size of the two-photon effects.

2 data tables

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AN INVESTIGATION OF THE 1.4-GeV/c**2 NUCLEON ISOBAR IN PROTON PROTON INTERACTIONS

Tan, T.H. ; Perl, Martin L. ; Martin, F. ; et al.
Phys.Lett.B 28 (1968) 195-198, 1968.
Inspire Record 52678 DOI 10.17182/hepdata.29198

The production of N ∗ (1400) isobar in the reaction pp → pN ∗+ (1400), where N ∗ (1400) → n π + and p π 0 , is investigated with the aid of one-pion exchange model. The one-pion exchange mechanism does not seem to dominate the production process. The isospin of N ∗ (1400) is found to be I = 1 2 , and the elasticity of the resonance is estimated to be 0.66.

1 data table

Axis error includes +- 0.0/0.0 contribution (?////Due to fitting mass spectrum).


NEUTRON - PROTON ELASTIC SCATTERING 8-GeV/c TO 30-GeV/c

Gibbard, Bruce G. ; Jones, Lawrence W. ; Longo, Michael J. ; et al.
Phys.Rev.Lett. 24 (1970) 22-24, 1970.
Inspire Record 52711 DOI 10.17182/hepdata.21622

The differential cross section for neutron-proton elastic scattering was measured in the diffraction region with incident-neutron momenta between 8 and 30 GeV/c. The experiment was a spark-chamber-counter experiment, conducted at the alternating-gradient synchrotron. Results are presented and compared with currently available lower energy np data and comparable energy pp data.

1 data table

No description provided.


NEUTRON - PROTON ELASTIC SCATTERING FROM 2-GeV/c TO 7-GeV/c

Perl, Martin L. ; Cox, Jack ; Longo, Michael J. ; et al.
Phys.Rev.D 1 (1970) 1857, 1970.
Inspire Record 54902 DOI 10.17182/hepdata.69198

Direct measurements were made of neutron-proton elastic scattering differential cross sections at high energies. A neutron beam with a continuous momentum spectrum between 1.2 and 6.7 GeV/c was scattered off a liquid hydrogen target, and spark chambers were used to determine the neutron scattering angle and, in a proton spectrometer, to measure the momentum and scattering angle of the recoil proton. Differential cross sections are presented over the incident neutron momentum range in intervals of the order of 0.5-GeV/c wide. The cross sections have an exponential peak in the forward direction and then flatten and become isotropic about the 90° c.m. scattering angle. At larger angles, the cross sections again rise towards the expected charge-exchange peak, which was not within the range of this experiment. There is little evidence of any other structure in the cross section. Values are presented for the slope of the diffraction peak, and comparisons are made between these slopes, and the 90° c.m. cross sections, for pp and np elastic scattering. The results presented here differ from those previously reported because of an error in a Monte Carlo calculation and in the availability of improved data on the real part of the np elastic scattering amplitude. At 5 GeV/c, a direct comparison of pp and np data allows the I=0 differential cross section to be extracted. The np data have been fitted in powers of cosθc.m. for |cosθc.m.|<0.8 for each energy range.

9 data tables

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MUON PROTON INELASTIC SCATTERING q**2 LESS THAN 1.2-GeV/c-**2

Dieterle, B. ; Braunstein, T. ; Cox, Jack ; et al.
Phys.Rev.Lett. 23 (1969) 1187-1190, 1969.
Inspire Record 54876 DOI 10.17182/hepdata.21667

The inelastic scattering of muons has been measured using positive muons of momentum 10 GeV/c incident upon a liquid-hydrogen target. We present values of the differential cross section and of the virtual photon-photon absorption cross section for |q| in the range 0.05 to 1.2 (GeV/c)2 and for equivalent photon laboratory energies of 0.6 to 6.5 GeV.

5 data tables

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High-Energy Inelastic e p Scattering at 6-Degrees and 10-Degrees

Bloom, Elliott D. ; Coward, D.H. ; DeStaebler, H.C. ; et al.
Phys.Rev.Lett. 23 (1969) 930-934, 1969.
Inspire Record 54874 DOI 10.17182/hepdata.21635

Cross sections for inelastic scattering of electrons from hydrogen were measured for incident energies from 7 to 17 GeV at scattering angles of 6° to 10° covering a range of squared four-momentum transfers up to 7.4 (GeV/c)2. For low center-of-mass energies of the final hadronic system the cross section shows prominent resonances at low momentum transfer and diminishes markedly at higher momentum transfer. For high excitations the cross section shows only a weak momentum-transfer dependence.

9 data tables

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

Axis error includes +- 0.0/0.0 contribution (?////FROM UNCERTAINTY IN ELECTRON-DETECTION EFFICIENCY).

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INELASTIC ELECTRON PROTON SCATTERING AT HIGH MOMENTUM TRANSFER

Breidenbach, Martin ;
PhD Thesis, 1970.
Inspire Record 61210 DOI 10.17182/hepdata.1058
11 data tables

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Cross sections for p p ---> d rho+ from 4.0 to 12.3 gev/c and a search for the delta+

Anderson, H.L. ; Dixit, M. ; Evans, H.J. ; et al.
Phys.Rev.Lett. 26 (1971) 108-112, 1971.
Inspire Record 69063 DOI 10.17182/hepdata.21629

Forward differential cross sections for isospin-1 bosons produced in p+p→d+x+ were measured using a deuteron missing-mass spectrometer at a small angle between 4.0- and 12.3−GeVc incident momentum. Differential cross sections for π+ and ρ+ were extracted from the spectra using phase-space backgrounds. They range from 10.4 to 0.4 μb/sr for π+ and from 1.4 to 0.3 μb/sr for ρ+. A bump near 6 GeVc appears in both dπ and dρ channels. No clear evidence is seen for higher-mass bosons. The possible δ+ cross sections average less than 0.01 μb/sr.

3 data tables

TECHNIQUE USED...ELECTRONIC. TABLE 1.

TECHNIQUE USED...MISSING MASS. BREIT WIGNER USED WITH FIXED WIDTH (150 MEV) AND VARIABLE MASS (LATTER VARIED WITH MOMENTA FROM 715 TO 765 MEV). 6 PERCENT NORMALIZATION ERROR; 20 PERCENT FROM BREIT WIGNER FIT. TABLE 1.

TECHNIQUE USED...MISSING MASS. CROSS-SECTIONS CORRESPOND TO VERY NARROW DELTA (962).


Amplitude analysis from decay correlations - application to pi- p ---> k*(0) lambda at 3.9 gev/c

Abramovich, M. ; Irving, A.C. ; Martin, Alan D. ; et al.
Phys.Lett.B 39 (1972) 353-357, 1972.
Inspire Record 75784 DOI 10.17182/hepdata.28306

Decay correlation data for π − p → K ∗ Λ at 3.9 GeV /c are analyzed to determine the amplitude structure. We emphasize combinations of observables invariant under rotations between s and t channel frames.

1 data table

No description provided.


Production of charged pions by 730-MeV protons from hydrogen and selected nuclei

Cochran, D.R.F. ; Dean, P.N. ; Gram, P.A.M. ; et al.
Phys.Rev.D 6 (1972) 3085-3116, 1972.
Inspire Record 73637 DOI 10.17182/hepdata.22253

An experiment was done in the external proton beam of the Berkeley 184-in. cyclotron to measure the production cross sections for pions from various target nuclei, from hydrogen to lead. The cross-section data are presented and the reaction mechanisms discussed. The hydrogen production appears to fit the one-pion-exchange model.

1 data table

No description provided.


Elastic electron - Proton Scattering at Large Four Momentum Transfer

Kirk, Paul N. ; Breidenbach, Martin ; Friedman, Jerome I. ; et al.
Phys.Rev.D 8 (1973) 63-91, 1973.
Inspire Record 73424 DOI 10.17182/hepdata.21999

Electron-proton elastic-scattering cross sections have been measured at the Stanford Linear Accelerator Center for four-momentum transfers squared q 2 from 1.0 to 25.0 (GeVc)2. The electric (GEp) and magnetic (GMp) form factors of the proton were not separated, since angular distributions were not measured at each q 2. However, values for GMp were derived assuming various relations between GEp and GMp. Several theoretical models for the behavior of the proton magnetic form factor at high values of q 2 are compared with the data.

22 data tables

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COMPARISON OF MUON - PROTON AND ELECTRON - PROTON INELASTIC SCATTERING

Braunstein, T. ; Lakin, W.L. ; Martin, F. ; et al.
Phys.Rev.D 6 (1972) 106, 1972.
Inspire Record 73463 DOI 10.17182/hepdata.22267

Measurements of the differential cross section for the inelastic scattering of 12-GeV/c muons on protons are reported. These measurements cover a kinematic range of |q2| (the square of the four-momentum transferred from the lepton) up to 4.0 (GeV/c)2 and of muon energy losses (ν) up to 9.0 GeV. Only the scattered muon is observed in an optical spark-chamber apparatus. The data are compared with electron-proton inelastic scattering, and analyzed in terms of possible lepton form factors and anomalous interactions. μ−p inelastic scattering is found to exhibit the same mild |q2| behavior as does e−p inelastic scattering. No experimentally significant deviation from the predictions of muon-electron universality has been found. If the ratio of muon to electron inelastic cross sections is parametrized by the form (1.0+|q2|ΛD2)−2, we find with 97.7% confidence that ΛD>4.1 GeV/c. The muon-proton cross sections on the average are slightly smaller than the electron-proton cross sections. This observation is not experimentally significant because such a difference might be caused by systematic errors, but this observation is used to speculate as to the most fruitful direction for future experiments.

6 data tables

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A SPARK CHAMBER MEASUREMENT OF THE REACTIONS PI+- P ---> RHO+- P AT 15-GEV/C

Pratt, J.C. ; Kaune, W.T. ; Lakin, W.L. ; et al.
Phys.Lett.B 41 (1972) 383, 1972.
Inspire Record 73430 DOI 10.17182/hepdata.28236

A new method, using spark chambers, for the study of the reactions π ± + p → ϱ ± + p is described. The charged pion and both γ rays from the π ± decay are detected. Differential and integrated cross sections σ π + =50 ± 9 μ b, σ π − =47 ± 9 μ b) for 0.0 ⩽| t |⩽1. (GeV/ c ) 2 and a laboratory momentum ( p Lab ) of 15 GeV/c are presented. The momentum dependence of σ γ ± is well fitted from 2.7 to 16 GeV/c by σ = K p Lab − with n γ + = 1.80 ± 0.80 and n γ − = 1.87 ± 0.15.

2 data tables

Axis error includes +- 17/17 contribution.

Axis error includes +- 17/17 contribution.


Elastic pi- p, k- p and anti-p p scattering at momenta of 25 and 40 gev/c

Antipov, Yu.M. ; Ascoli, G. ; Busnello, R. ; et al.
Yad.Fiz. 18 (1973) 353-363, 1973.
Inspire Record 84824 DOI 10.17182/hepdata.19259
1 data table

No description provided.


Elastic scattering of pi- p, K- p and anti-p p at 25-GeV/c and 40-GeV/c

Antipov, Yu.M. ; Ascoli, G. ; Busnello, R. ; et al.
Nucl.Phys.B 57 (1973) 333-347, 1973.
Inspire Record 80976 DOI 10.17182/hepdata.32554

Elastic diffraction scattering of π − , K − and p on protons has been measured at 25 and 40 GeV/c at the Serpukhov Proton Accelerator. Differential elastic cross sections and diffraction slopes are presented in the momentum-transfer interval 0.07–0.80 (GeV/ c ) 2 and compared with existing data at lower energies.

4 data tables

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High-Energy Single-Arm Inelastic e - p and e - d Scattering at 6-Degrees and 10-Degrees

Poucher, J.S. ; Breidenbach, Martin ; Ditzler, W.R. ; et al.
Phys.Rev.Lett. 32 (1974) 118, 1974.
Inspire Record 81157 DOI 10.17182/hepdata.3374

Differential cross sections for electron scattering from hydrogen and deuterium in the deep-inelastic region show that the neutron cross section is significantly smaller than the proton cross section over a large part of the kinematic region studied. Although νW2d differs in magnitude from νW2p, it exhibits a similar scaling behavior.

3 data tables

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The Discovery of a Second Narrow Resonance in e+ e- Annihilation

Abrams, G.S. ; Briggs, D. ; Chinowsky, William ; et al.
Phys.Rev.Lett. 33 (1974) 1453-1455, 1976.
Inspire Record 91611 DOI 10.17182/hepdata.21287

We have observed a second sharp peak in the cross section for e+e−→hadrons at a center-of-mass energy of 3.695±0.004 GeV. The upper limit of the full width at half-maximum is 2.7 MeV.

1 data table

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Polarization Measurements in pi+ p Elastic Scattering from 0.6-GeV/c to 2.65-GeV/c

Martin, J.F. ; Sleeman, J.C. ; Brown, Robert M. ; et al.
Nucl.Phys.B 89 (1975) 253-286, 1975.
Inspire Record 90870 DOI 10.17182/hepdata.6743

This paper presents the results of a counter experiment at the Rutherford Laboratory, in which the polarization parameter in π + p elastic scattering was measured. Data were taken at 64 incident pion momenta between 0.60 and 2.65 GeV/ c . The results are found to be in generally good agreement with those of other experiments, and have substantially higher precision at many momenta.

128 data tables

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