Barnes, A.V
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Study of Neutrino Interactions in Hydrogen and Deuterium. 1. Description of the Experiment and Study of the Reaction Neutrino d --> mu- p p(s)

Barish, S.J. ; Campbell, J. ; Charlton, G. ; et al.
Phys.Rev.D 16 (1977) 3103, 1977.
Inspire Record 5566 DOI 10.17182/hepdata.24481

This paper gives a detailed description of an experiment which studies the interactions of muon-type neutrinos in hydrogen and deuterium. The experiment was performed at the Zero Gradient Synchrotron using the wide-band neutrino beam incident on the Argonne 12-foot bubble chamber filled with hydrogen and deuterium. The neutrino energy spectrum peaks at 0.5 GeV and has a tail extending to 6 GeV. The shape and intensity of the flux is determined using measurements of pion yields from beryllium. The produced pions are focused by one or (for the latter part of the experiment) two magnetic horns. A total of 364000 pictures were taken with a hydrogen filling of the bubble chamber and 903 000 with a deuterium filling. The scanning and other analyses of the events are described. The most abundant reaction occurs off neutrons and is quasi-elastic scattering νd→μ−pps. The separation of these events from background channels is discussed. The total and differential cross sections are analyzed to obtain the axial-vector form factor of the nucleon. Our result, expressed in terms of a dipole form factor, gives an axial-vector mass of 0.95±0.09 GeV. A comparison is made to previous measurements using neutrino beams, and also to determinations based upon threshold pion electroproduction experiments. In addition, the data are used to measure the weak vector form factor and so check the conserved-vector-current hypothesis.

1 data table
Table 1

Measured Quasi-Elastic total cross section.


Properties of the Hadronic System Resulting from anti-Muon-neutrino p Interactions

Derrick, M. ; Gregory, P. ; Hyman, L.G. ; et al.
Phys.Rev.D 17 (1978) 1, 1978.
Inspire Record 120660 DOI 10.17182/hepdata.24454

The properties of the final-state hadronic system in antineutrino-proton charged-current interactions are presented. The events were observed in the Fermilab 15-foot hydrogen bubble chamber. The average energy of the events is ∼30 GeV, but there are some interactions beyond 100 GeV. The mean multiplicity of the charged hadrons varies as 〈nCH〉=(0.06±0.06)+(1.22±0.03)lnW2 for hadronic masses W in the range 1.0<W2<50 GeV2. By contrast, the multiplicity depends only weakly on the four-momentum transfer between the leptons. The mean pion multiplicities for events with three or more charged tracks are found to be 〈n−〉=1.64±0.04, 〈n0〉=1.16±0.13, for π− and π0 production, respectively. By comparing the number of positive tracks with π− data from neutrino production, we deduce a mean proton multiplicity 〈np〉 of 0.53 ± 0.15. The single-particle distributions in both longitudinal and transverse momentum are found to be similar to those for nondiffractive production in hadronic collisions. The fragmentation properties of the final-state d quarks are compared to the expectations of the quark-parton model. The fraction of observed neutral-strange-particle production for events with three or more charged tracks is 0.08 ± 0.015 and is consistent with coming completely from associated production.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Study of the Reaction K- p --> anti-K0 n at Momenta of 25-GeV/c and 40-GeV/c

The Serpukhov-CERN collaboration Apel, W.D. ; Bertolucci, E. ; Donskov, S.V. ; et al.
Nucl.Phys.B 129 (1977) 275, 1977.
Inspire Record 120460 DOI 10.17182/hepdata.35232

Measurements were made of the differential cross sections for the charge exchange of K − mesons on protons at momenta of 25 and 40 GeV/ c using a high-precision spectrometer with no magnetic field. In the range 5–40 GeV/ c the reaction cross section follows a power-law dependence p K − −1.52 . In the snall momentum transfer region (− t ⪅ m π 2 ) a minimum is observed, similar to that discovered at lower energies. The differential cross sections t = 0 are considerably less than those predicted by the Regge-pole model. The parameters of the effective trajectory are determined.

2 data tables

Reaction pi- p --> eta n at Large Momentum Transfer

The Serpukhov-CERN collaboration Apel, W.D. ; Augenstein, K. ; Bertolucci, E. ; et al.
Sov.J.Nucl.Phys. 27 (1978) 82-83, 1978.
Inspire Record 119329 DOI 10.17182/hepdata.11051

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Formation of the Sigma (2030) Resonance in the Reactions K- n --> Sigma- pi0 and K- n --> Sigma0 pi- in the Center-Of-Mass Energy Interval 1850-MeV to 2150-MeV

Goyal, D.P. ; Sodhi, A.V. ;
Phys.Rev.D 16 (1977) 2746-2753, 1977.
Inspire Record 126664 DOI 10.17182/hepdata.24480

A partial-wave analysis of the pure isospin I = 1 reactions K−n→Σ−π0 and K−n→Σ0π− in the center-of-mass energy range 1850-2150 MeV is reported. The decay mode Σ(2030)→Σπ is observed with a branching ratio xr given by eiφ(xexr)12 = −0.085±0.02, where xe is the elasticity and φ is the relative phase of the resonance with the phase of Σ(1765) taken to be zero.

2 data tables
Table 1

LEGENDRE COEFFICIENTS FOR EVENTS WITH SEEN SPECTATORS.

Table 2

LEGENDRE COEFFICIENTS FOR ALL EVENTS.


Inclusive Neutrino p and Neutrino n Charged-Current Neutrino Reactions Below 6-GeV

Barish, S.J. ; Derrick, M. ; Dombeck, T. ; et al.
Phys.Lett.B 66 (1977) 291-294, 1977.
Inspire Record 4240 DOI 10.17182/hepdata.27596

Results are presented of a study of inclusive ηp and ηn interactions from threshold to 6 GeV. The data show a rapid approach to the distributions expected in the naive quark-parton model. The charged-current η deuteron total cross section is fit by the expression σ T ( η d) = (0.76 ± 0.03) × 10 −38 E η cm 2 per GeV per nucleon. For E η > 1.5 GeV, we measure σ T ( η n)/ σ T ( η p) = (2.02 ± 0.23). The distributions in the scaling variables x and y are given and discussed.

1 data table
Table 1

Measured charged current total cross section.


The Reaction pi- p --> omega N at Momenta from 20-GeV/c to 200-GeV/c

Dahl, O.I. ; Johnson, R.A. ; Kenney, R.W. ; et al.
Phys.Rev.Lett. 38 (1977) 54, 1977.
Inspire Record 110620 DOI 10.17182/hepdata.20987

The reaction π−p→ωn in the beam-momentum range from 20 to 200 GeV/c has been studied using data acquired at Fermilab. In this Letter, the integral and differential cross sections for this reaction are presented. The integral cross sections are considerably larger than those previously reported. The differential cross sections can be reproduced quite easily by Regge models. As predicted by such models, natural-parity exchange dominates production throughout this energy region.

3 data tables
Table 1

D(SIG)/DT IS AVERAGE OVER T INTERVAL WITH NO FINITE-BIN-WIDTH CORRECTIONS.

Table 2

No description provided.

Table 3

REPRESENTATIVE SPIN DENSITY MATRIX ELEMENTS.


pi+ p, K+ p and p p Topological Cross-Sections and Inclusive Interactions at 100-GeV Using a Hybrid Bubble Chamber-Spark Chamber System and a Tagged Beam

Morse, W.M. ; Barnes, V.E. ; Carmony, D.D. ; et al.
Phys.Rev.D 15 (1977) 66, 1977.
Inspire Record 108830 DOI 10.17182/hepdata.24534

π+p, K+p, and pp interactions at 100 GeV are studied using the Fermilab hybrid 30-inch bubble chamber with associated downstream multiparticle spectrometer and an unseparated tagged positive beam. Topological cross sections and charged-particle-multiplicity moments are presented and good agreement is found with Koba-Nielsen-Olesen scaling. The charged-multiplicity second moment, f2cc, and the second moment of produced (+ -) pairs, f2−−, are presented both with and without the diffractive-dissociation events, and are discussed in terms of the two-component model invoked to explain pp multiplicity distributions above 100 GeV. Single-particle inclusive distributions are presented and studied in terms of the Regge-Mueller forms of approach to scaling at asymptotic energies. Pomeron factorization is found to hold in the target-proton-associated backward center-of-mass hemisphere for inclusive particle production by incident π+, K+, and protons.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


The Reaction pi- p ---> eta n at High-Energies

Dahl, O.I. ; Johnson, R.A. ; Kenney, R.W. ; et al.
Phys.Rev.Lett. 37 (1976) 80, 1976.
Inspire Record 108647 DOI 10.17182/hepdata.21028

Measurements on the reaction π−p→ηn have been carried out at Fermilab with beam energies from 20 to 200 GeV in the same experiment in which pion charge-exchange scattering was studied. The differential cross sections have a pronounced dip in the forward direction. The data can be described well by a simple Regge-pole model but the resulting A2 trajectory is not degenerate with the ρ trajectory extracted from the charge-exchange data.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////).


Pion Charge Exchange Scattering at High-Energies

Barnes, A.V. ; Mellema, D.J. ; Tollestrup, A.V. ; et al.
Phys.Rev.Lett. 37 (1976) 76, 1976.
Inspire Record 108646 DOI 10.17182/hepdata.21046

We report on a study of pion charge-exchange scattering carried out at Fermilab in the energy range 20 to 200 GeV. The results can be described remarkably well by a simple Regge-pole model. The charge-exchange cross sections in the forward direction lead to a prediction for the difference in total cross sections of π−p and π+p which is in satisfactory agreement with direct measurements of this difference in another experiment at Fermilab.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////).