Using the Primakoff formalism, we have extracted the radiative decay width of the A + 2 (1310) produced in coherent interactions of 200 GeV/ c π + mesons in nuclear targets. The width obtained is 295 ± 60 keV, a value consistent with quark-model predictions.

Using the Primakoff formalism, we have extracted the radiative decay width of the K ∗+ (1430) produced in coherent interactions of 200 GeV/ c K + mesons in nuclear targets. The width obtained is 240 ± 45 keV, a value reasonably consistent with quark-model predictions.

Coherent production of Kπ systems observed in the excitation of 200-GeV/c positive kaons on nuclear targets has been analyzed, including both electromagnetic and strong contributions, to yield a new value for the radiative width for the process K*+(890)→K+γ of 51 ± 5 keV.

From analysis of V0 events observed in an exposure of the National Accelerator Laboratory 30-in. bubble chamber to 303−GeVc protons, we obtain these results: (1) 〈nπ0〉 rises approximately linearly with n-, implying strong coupling of neutral and charged pions, while 〈nKS0〉 is less coupled to n; (2) γ, KS0, and Λ0 production cross sections are approaching a scaling limit by 303 GeVc; (3) within the limited statistics, dσdy is flat in the central region for KS0 and low-multiplicity γ events.

We have measured the single-particle inclusive cross sections for p+p→π±+X, K±+X, p+X, p¯+X in the low-p⊥ region (≲ 1.5 GeV/c) as a function of the radial scaling variable XR in p−p collisions at 100, 200, and 400 GeV at Fermilab. The measured π+π− and K+K− ratios are shown to be remarkably similar to the same ratios which have recently been measured at large p⊥ at 90° in the center-of-mass system.

Differential cross sections have been measured at Fermilab with a focusing spectrometer for π±p, K±p, and p±p elastic scattering at 50-, 70-, 100-, 140-, and 175-GeV/c incident momentum over the |t| range 0.03 to 0.8 GeV2. The results are smooth in t and are parametrized by quadratic exponential fits.

In a 35 000-picture exposure of the Fermilab 30-in. hydrogen bubble chamber to a 300-GeV/c proton beam 1863 neutral V0's were measured. The inclusive cross sections for γ, Ks0, Λ0Σ0, and Λ¯0Σ¯0 are 257 ± 18 mb, 7.3 ± 0.6 mb, 3.6 ± 0.4 mb, and 1.0 ± 0.3 mb, respectively. The correlation with charged particles and other inclusive features are studied.

We have measured the elastic cross section for pp, p¯p, π+p, π−p, K+p, and K−p scattering at incident momenta of 70, 100, 125, 150, 175, and 200 GeV/c. The range of the four-momentum transfer squared t varied with the beam momentum from 0.0016≤−t≤0.36 (GeV/c)2 at 200 GeV/c to 0.0018≤−t≤0.0625 (GeV/c)2 at 70 GeV/c. The conventional parametrization of the t dependence of the nuclear amplitude by a simple exponential in t was found to be inadequate. An excellent fit to the data was obtained by a parametrization motivated by the additive quark model. Using this parametrization we determined the ratio of the real to the imaginary part of the nuclear amplitude by the Coulomb-interference method.

A study of 205-GeV/c π−p interactions has been made with a 48 800-picture exposure in the bare Fermilab 30-inch hydrogen bubble chamber. The average number of charged particles produced per inelastic interaction is 7.99±0.06. The elastic cross section is 3.18±0.13 mb and the total cross section is 24.19±0.44 mb. The inclusive cross sections for neutral-particle production are: σ(γ)=171.3±15.3 mb, σ(KS0)=3.64±0.61 mb (x<0.3), σ(Λ)=1.71±0.34 mb (x<0.3), and σ(Λ¯)=0.59±0.23 mb (x<0.1). The average number of π0's produced per inelastic collision is consistent with a linear rise with the number of charged particles, and about equal to the number of produced π− or π+. The average number of K0's, Λ's, and Λ¯'s is consistent with very little dependence on the number of charged particles. General characteristics of neutral-particle production are presented and compared with other experiments. For each topology the produced neutral energy is ∼13 of the incident energy.

The differential cross section for π±, K±, and p± on hydrogen have been measured in the range 0.07<−t<1.6 (GeV/c)2. The dependence on momentum, momentum, transfer, and particle type are discussed.

Elastic scattering of hadrons on protons has been measured at momenta of 50, 100, and 200 GeV/c. The meson-proton scattering is found to be independent of momentum and meson type for −t>0.8 (GeV/c)2. The momentum dependence of the pp dip at −t=1.4 (GeV/c)2 was investigated. Slope parameters are given.

Data are presented on elastic πp and Kp scattering for values of −t up to 2.5 and 3.5 (GeV/c)2 at incident momenta of 100 and 200 GeV/c, respectively. All of the cross sections are found to be nearly identical, although there is some momentum dependence of the π+p data; a small systematic difference observed between pion and kaon data cannot be explained by geometrical scaling.

We have observed the production of the Ds± by a high-energy neutron beam on nuclear targets. The Ds± was observed in the decay mode Ds±→φπ±, φ→K+K−. The average of the inclusive cross sections for Ds+ and Ds− hadroproduction is measured to be BdσdxF=2.85±0.80±0.86 μb/nucleon at xF=0.175 on the assumption of a linear A dependence, where B≡Γ(Ds±→φπ±)Γ(Ds±→all).

Results are presented on π±p, K±p, and p±p elastic scattering measured with an apparatus having acceptance of 0.5<−t<2.5 (GeV/c)2 and 0.9<−t<11 (GeV/c)2 at 100 and 200 GeV/c, respectively. A diffractionlike dip is seen for the first time in the π−p t distribution at −t=4 (GeV/c)2. All meson-proton cross sections are found to be similar in the range 1<−t<2.5 (GeV/c)2, although some small systematic differences are observed. Cross sections for pp and p―p are compared with previous data.

We have used the ratio between the production rates of $K^0$'s and $π^−$'s in antineutrino-nucleon interactions in the Fermilab 15 ft bubble chamber to measure the size of the SU (3) symmetry violation in the production of quark-antiquark pairs to be 0.27 ± 0.04. This value is significantly larger than the value obtained from a recent ep experiment. There is no apparent dependence of the $K^0$/$π^−$ ratio with $W^2 , Q ^2 , x_b$ or $p_T^2$ .

The results of a study of strange particle production in charged current $\bar{\nu}_{\mu} N$ interactions in the Fermilab 15 ft bubble chamber filled with a heavy $Ne-H_2$ mixture are presented. Production rates and average multiplicities of $K^0$'s and Λ's as functions of W 2 and Q 2 are given. The experimental data agree well with the quark-parton model predictions if a yield of 0.06 ± 0.02 of $K^0$'s and Λ's from charm production is included. Upper limits for D-meson production are given and the shape of the charmed quark fragmentation function is discussed. Inclusive production of the K ∗ (890) and Σ(1385) resonances is measured and it is shown that only about 5% of the K 0 mesons and Λ hyperons results from resonance decays. Relative production rates of neutral strange particles on proton and neutron targets are studied.

We derive cross-sections for the inclusive productiion in p̄p interactions at 100 GeV /c of π 0 , K S 0 and Λ 0 Λ 0 of 91.5±5.7 mb, 5.2±0.4 mb and 4.8±0.4 mb respectively, which are all higher than pp cross-sections at energy. We find indications that these differences can be attributed to “annihilation” processes.

We have investigated the inclusive production of γ, KS0, Λ0, and Λ¯0 in 100-GeV/c p¯p interactions in the 30-in. hydrogen bubble chamber at Fermilab. We present various inclusive distributions and compare them with corresponding distributions in 100-GeV/c pp interactions and lower-energy p¯p interactions. We find some evidence for Σ(1385) production but none for K*(890) production. We find evidence for a nonzero Λ0 polarization of -0.45 ± 0.21.

We present results on inclusive particle production in the antineutrino charged current induced hadron jets observed in the Fermilab 15 ft bubble chamber. Fractional energy distributions, particle ratios and average multiplicities of the hadrons in the jets are measured. Ratios between the inclusive production rates of different mesons in the jets are studied to seek evidence for the d-quark origin of the observed hadrons. Good over-all agreement with the hypothesis of d-quark fragmentation with universal fragmentation functions obeying isospin systematics is established.

The polarization parameter for K + p elastic scattering has been measured at 1.60, 1.80, 2.11 and 3.31 GeV/ c incident momenta over the entire angular range with an emphasis on the backward region. The results in the extreme backward region appear to be small and consistent with zero.

We have measured the polarization of Λ and Λ hyperons produced by 800 GeV protons on a Be target at a fixed targeting angle of 4.8 mrad. Comparison with previous data at 400 GeV production energy and twice the targeting angle shows no significant energy dependence for the Λ polarization. This is in striking contrast to the energy dependence found for σ + and Ξ − polarizations. We find no evidence for Λ polarization at 800 GeV.

We have observed diffraction dissociation of KL0 mesons with a carbon target into the exclusive final states KS0π+π−, KS0ω, and KS0φ. The diffraction production cross section for these states is not strongly dependent on the incident energy, varying at most by 30% between 75 and 150 GeV. The mass distributions do not change appreciably as a function of laboratory energy. The ratio of the diffractive mass-threshold production of K*±π∓, KS0ρ, KS0ω, and KS0φ is compared with previously obtained lower-energy data.

Measurements of inclusive transverse-momentum spectra for KS0 mesons produced in proton-antiproton collisions at s of 630 and 1800 GeV are presented and compared with data taken at lower energies. The ratio, as a function of pT, of the cross section for KS0 to that for charged hadrons is very similar to what is observed at lower energies. At 1800 GeV, we calculate the strangeness-suppression factor λ=0.40±0.05.

An experiment using the Fermilab Single Arm Spectrometer (SAS) facility and an associated nonmagnetic vertex detector studied the reactions a+p→c+X, where a and c were π±, K±, p, or p¯. Extensive measurements were made at 100 and 175 GeV/c beam momenta with the outgoing hadrons detected in the SAS covering a kinematic range 0.12<x<1.0 and pT<1.25 GeV/c. Additional data covering a more restricted range in x were also gathered at 70 GeV/c incident momentum. In this high-statistics experiment, the identification of both the incoming and outgoing charged hadrons were made with a total of eight Čerenkov counters. New and extensive single-particle inclusive data for charged-particle production in low-pT hadronic fragmentation are presented. The average associated charged-particle multiplicity and pseudorapidity distributions are also given.

Results of high-transverse-momentum charged-hadron production in 400-GeV/c proton-proton and proton-deuteron collisions and 800-GeV/c proton-proton collisions are presented. The transverse-momentum range of the data is from 5.2 to 9.0 GeV/c for the 400-GeV/c collisions and from 3.6 to 11.0 GeV/c for the 800-GeV/c collisions; the data are centered around 90° in the proton-nucleon center-of-momentum system. Single-pion invariant cross sections and particle ratios were measured at both energies. The results are compared to previous experiments and the Lund model.