None
No description provided.
The photoproduction of neutral pions from hydrogen has been studied by counting the recoil protons with a magnetic spectrometer and scintillation counters. The process has been studied between photon energies of 260 and 450 Mev and between center-of-momentum pion angles of 70° and 153°. The excitation functions show a resonance type shape with maxima at about 320 Mev. Angular distributions are analyzed in the form A+Bcosθ+Ccos2θ in the center-of-momentum system. The coefficient B, which gives the front-back asymmetry, is small at all energies; and the ratio −AC is 1.22±0.10 at all energies between 295 and 450 Mev. The maximum cross section at 90° in the c.m. system is 26×10−30 cm2/steradian for 320-Mev photons. The total cross section divided by the square of the c.m. photon wavelength has a maximum near 340 Mev, and drops by nearly a factor of two at 450 Mev. These results are consistent with magnetic dipole and electric quadrupole absorption leading to a resonant state of the pion-nucleon system of angular momentum 32 and isotopic spin 32.
No description provided.
No description provided.
No description provided.
This paper reports measurements of the differential cross section for photoproduction of neutral pions in hydrogen at energies 300, 400, and 450 Mev, at center-of-momentum angles of 70° to 150°. One decay photon from the neutral pion is observed in coincidence with the recoil proton, whose energy and angle are measured to define the photon energy. The results obtained by this method are in good agreement with more accurate measurements obtained recently by the method of observing only the recoil proton.
No description provided.
No description provided.
No description provided.
Positive pions produced in a cold, high-pressure hydrogen gas target by the 500-Mev bremsstrahlung of the CalTech synchrotron, have been analyzed by a large magnetic spectrometer. The photoproduction cross section has been measured as a function of photon energy at laboratory angles of 12.5°, 30°, 51°, 73°, 104°, 140°, and 180°. The energy region covered depends somewhat on the angle, but is typically from 200 to 470 Mev. From these excitation curves the angular distribution of the photopions in the center of momentum system is obtained for various photon energies, and these angular distributions are analyzed in the form A+Bcosθ+Ccos2θ. The angular distribution has a backward maximum at low energies and a forward maximum at high energies, the coefficient B changing sign at about 340 Mev. The total cross section shows a striking maximum near 290 Mev, of magnitude 205×10−30 cm2, and falls off above the maximum faster than λ2.
No description provided.
No description provided.
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No description provided.
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The ratio of the yields of negative and positive pions photoproduced in deuterium has been measured at six photon energies between 500 and 1000 Mev and at seven angles between 20° and 160° in the center-of-momentum system of the photon and target nucleon. Pions were selected with a magnetic spectrometer and identified using momentum and specific ionization in a scintillation counter telescope. The spectator model of the deuteron was used to identify the photon energy. Statistical errors assigned to the π−π+ ratio range between five and fifteen percent. The results of the present experiment join smoothly with the low-energy π−π+ ratios obtained by Sands et al. At high energies the π−π+ ratio varies from 0.5 at forward angles and energies near 900 Mev to 2.5 at 160° c.m. and energies 600 to 800 Mev. The cross sections for π− photo-production from neutrons have been derived from the π−π+ ratio and the CalTech π+ photoproduction data. The angular distributions for π− production are considerably different from those for π+; there is, for example, a systematic increase at the most backward angles. The energy dependence of the total cross section for π− is similar to that for π+, although the second resonance peak occurs at a slightly lower energy, and at 900 and 1000 Mev the π− cross section is smaller by a factor 1.6. A comparison is made of the cross sections for π+ photoproduction from hydrogen and deuterium, although the accuracy of this comparison is not high.
No description provided.
No description provided.
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'1'. '2'.
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A total of 24 360 events having two charged particles in the final state from π−+p interactions at an incident π− momentum of 2.7 GeVc have been analyzed. The final states π−π+n and π−π0p are found to be dominated by rho-meson production, and in addition, significant N*(1238) production is seen. The partial cross sections for the dominant resonant channels are σ=(pρ−)=(1.3±0.2) mb, σ(nρ0)=(2.3±0.2) mb, and σ[π−N*+(→pπ0)]=(0.5±0.2) mb. The production of the ρ− and ρ0 and the decay of the ρ− agree very well with the predictions of an absorption-modified one-pion-exchange model. The production angular distributions of the ρ0 and ρ− follow an exponential of the form Ae+Bt. The results from a least-squares fit give B(ρ−)=9.32±0.08 (GeVc)−2, B(ρ0)=10.26±0.06 (GeVc)−2. A similar analysis for the elastic-scattering events gave B(el)=7.77±0.05 (GeVc)−2. The ρ0 decay distributions are asymmetric and they have been analyzed using a simple model which includes S−P-wave interference. No clear evidence is seen for a T=0, J=0 resonance at a mass near that of the ρ. The N*(1238) resonance production is found to be in agreement with the ρ-exchange model of Stodolsky and Sakurai. Indication of other resonance production with small cross section is seen, such as A1 and A2 production in the multiple missing neutral events. The masses and widths of the ρ0 and ρ− as a function of the four-momentum transfer squared to the nucleon have been determined.
No description provided.
The differential cross section for the reaction γ+p→π++n was measured at 32 laboratory photon energies between 589 and 1269 MeV at the Caltech synchrotron. At each energy, data have been obtained at typically 15π+ angles between 6° and 90° in the center-of-mass (c.m.) system. A magnetic spectrometer was used to detect the π+ photoproduced in a liquid-hydrogen target. Two Cerenkov counters were used to reject background of positrons and protons. The data clearly show the presence of a pole in the production amplitude due to one-pion exchange. Moravcsik fits to the angular distributions, including data from another experiment carried out by Thiessen, are presented. Extrapolation of these fits to the pole gives a value for the pion-nucleon coupling constant of 14.2±1.7, which is consistent with the accepted value. The "second" and "third" pion-nucleon resonances are evident as peaks in the total cross section and as changes in the shape of the angular distributions. At the third resonance, there is evidence for both a D52 and an F52 amplitude. The absence of large variations with energy in the 0° and 180° cross sections implies that the second and third resonances are mostly produced from an initial state with helicity 32.
No description provided.
No description provided.
No description provided.
An analysis of π−p two-prong interactions at 4.16 GeV/c is presented. The total two-prong cross section is 19.11±0.40 mb, based on 33 672 events. The elastic-scattering differential cross section shows an exponential behavior, Kexp(−AΔ2). With A=7.36±0.14 GeV−2, the "absorption parameters" are derived as C+=0.846±0.017 and γ+=0.040±0.001. The final-state π−π0p exhibits a strong ρ−, and the π−π+n a strong ρ0 and f0. The partial cross sections for the dominant resonant channels pρ−, π−Δ+(1236) (→pπ0), ρ0n, and f0n are 0.59±0.03, 0.17±0.01, 1.15±0.05, and 0.53±0.06 mb, respectively. The ρ− production and decay angular distributions do not agree with the predictions of the absorption-modified one-pion-exchange model. However, an inclusion of the contribution from ω exchange adequately accounts for the discrepancy. The ρ0 asymmetry is interpreted as a result of an interference of the resonant P wave and isospin-zero S wave, and the corresponding spin-density matrix elements are obtained. In the final state π−p+neutrals, a clear peak for the η meson and some evidence for the ω meson are seen.
Axis error includes +- 0.0/0.0 contribution (?////EVENT NORMALIZATION).
The cross section for the elastic scattering of positrons from protons has been compared with the corresponding electron cross section using secondary beams derived from the photon beam of the Cornell 2-GeV synchrotron. The paths of the scattered leptons (positrons or electrons) and recoil protons were recorded in spark chambers and were used to determine the incident lepton energy of each event. Elastic scatterings were identified by requiring coplanarity and a fit to the scattering kinematics. The detection system was sensitive to scattering angles between 25° and 75°. The ratio of the positron cross section to the corresponding electron cross section was 0.992±0.017 at 800 MeV and 0.987±0.019 at 1200 MeV. No significant variation of the ratio with angle of scattering was found.
No description provided.
No description provided.
The polarization of recoiling protons from the photoproduction of π0 mesons on liquid hydrogen has been measured for primary photon energies between 500 and 1000 MeV over a range of π0 c.m. angles from 55° to 130°. The results show structure not observed previously in experiments of less precision. In particular, the polarization at 90° c.m. is close to zero at a primary photon energy of 900 MeV. Also, a strong dependence of polarization on π0 c.m. angle between 600 and 900 MeV was observed. A subsidiary measurement of the polarization of the recoil protons from elastic e−p scattering at 900 MeV and q2=10 F−2 gave a value (1.3±2.0)%.
No description provided.
No description provided.
No description provided.
Total cross sections of K± and p¯ on hydrogen and deuterium were measured in a standard transmission experiment with statistical precisions of the order of 0.05-0.25%. Data were obtained in the momentum range 2.45-3.30 GeV/c for K−N, 1.55-3.30 GeV/c for K+N, and 1.00-3.30 GeV/c for p¯N. Cross sections for the pure isotopic spin states are obtained using a procedure for the deuterium data which takes into account Fermi motion and the shadow effect. Evidence for the following new structures was found: Y1*(2455), Y1*(2620), Y0*(2585), Z1*(2150), Z1*(2500), π1*(2290), π1*(2350), and π0*(2375).
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In a new measurement of proton total cross sections at 3.00 GeV/c, the p−d total cross section is found to be lower than a previous measurement by 1.17±0.09 mb. This implies a corresponding new value for the total cross section for I=0 which is 2.18±0.27 mb lower than the previous value. Possible sources of systematic error are discussed.
No description provided.
'1'. '2'. '3'. '5'.
No description provided.
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.
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).
The reaction K + p → K ∗o (892) Δ ++ (1236) has been studied at 3 GeV/ c in both a hydrogen and a deuterium bubble chamber experiment. The production mechanism is described by a Regge-type model using π- and B-exchange. The joint decay distributions are analysed in various frames and compared with quark-model predictions.
No description provided.
No description provided.
No description provided.
As a partial result of an analysis of K + d interactions at 3 GeV/ c produced in the 81 cm Saclay bubble chamber, we present data on K + differential cross sections for the following reactions: K + d → K + d, K + d → K + pn, K + d → K 0 pp . A set of parameters describing the K + n elastic scattering has been obtained from a simulataneous fit, based on the Glauber model. to the three experimental differential cross sections and to the K + d total cross section, giving α n = 1.7 ± 0.5 GeV −2 for the slope α n of the differential cross section, and ρ n = −0.16 ± 0.3 for the ratio of the real to the imaginary part of the forward scattering amplitude. The D-wave function of the deuteron has been found to give a non-negligible contribution to the coherent reaction.
No description provided.
No description provided.
No description provided.
We have measured the differential cross section for small angle p−p scattering from 25 to 200 GeV incident energy and in the momentum transfer range 0.015<|t|<0.080 (GeVc)2. We find that the slope of the forward diffraction peak, b(s), increases with energy and can be fitted by the form b(s)=b0+2α′ lns, where b0=8.3±1.3 and α′=0.28±0.13 (GeVc)−2. Such dependence is compatible with the data existing both at higher and lower energies. We have also obtained the energy dependence of the p−p total cross section in the energy range from 48 to 196 GeV. Within our errors which are ± 1.1 mb the total cross section remains constant.
No description provided.
THE TOTAL CROSS SECTION IS NORMALIZED TO 38.5 +- 0.1 MB AT 48 GEV. IT HAS BEEN DERIVED USING THE OPTICAL THEOREM FROM THE EXTRAPOLATED FORWARD ELASTIC CROSS SECTION AND WITH ALPHA = -0.09.
We present new data for the reaction K−p→Ξ−K+ at 3.9-, 4.6-, and 5.0-GeV/c incident momenta. We compare the behavior of K−p→Ξ−K+ with K+p→pK+ backward scattering using a simple model with Reggeized baryon exchange and SU(3).
CROSS SECTION IS NEARLY ALL BACKWARD PRODUCTION.
No description provided.
No description provided.
Invariant cross-sections are presented for the inclusive reaction p + p → π o + anything, Measurements of large transverse momentum π o 's (2.5 GeV/ c < p ⊥ <9 GeV/ c ) were made near 90° at the CERN ISR at five centre-of-mass energies (√ s = 23.5, 30.6, 44.8, 52.7 and 62.4 GeV. At large p ⊥ , the invariant cross-sections are seem to vary with s and p ⊥ , in good agreement with a fit of the form Ap ⊥ − n F ( p ⊥ /√ s ), with n ≈8 and F ( p ⊥ /√ s )≈ exp (−26 p ⊥ /√ s ).
No description provided.
No description provided.
No description provided.
From measurements of proton-proton elastic scattering at very small momentum transfers where the nuclear and Coulomb amplitudes interfere, we have deduced values of ρ, the ratio of the real to the imaginary forward nuclear amplitude, for energies from 50 to 400 GeV. We find that ρ increases from -0.157 ± 0.012 at 51.5 GeV to +0.039 ± 0.012 at 393 GeV, crossing zero at 280 ± 60 GeV.
No description provided.
The slope b(s) of the forward diffraction peak of p−p elastic scattering has been measured in the momentum-transfer-squared range 0.005≲|t|≲0.09 (GeV/c)2 and at incident proton energies from 8 to 400 GeV. We find that b(s) increases with s, and in the interval 100≲s≲750 (GeV)2 it can be fitted by the form b(s)=b0+2α′lns with b0=8.23±0.27, α′=0.278±0.024 (GeV/c)−2.
MOMENTUM BINS ARE APPROX 20 GEV WIDE CENTRED AT THE GIVEN PLAB EXCEPT FOR THE 9 AND 12 GEV POINTS WHICH HAVE WIDTHS OF APPROX 1 AND 4 GEV RESPECTIVELY.
Results are presented on an analysis of the reaction K + p → K ∗+ (890) p at 16 GeV/ c and compared with data at lower incident momenta and with corresponding results for the reaction K − p → K ∗− (890) p. It is found for both reactions that the energy dependence of the cross section exhibits a simple ( p − n lab behaviour.
BREIT-WIGNER RESONANCE FITS WITH BACKGROUND.
We have used an optical spark-chamber spectrometer to perform a systematic study of the reaction π−p→ΛK0 at beam momenta between 930 and 1130 MeV/c. The cross section, angular distribution, and Λ polarization have been measured. We present our complete data from a sample of 11 400 events along with Legendre polynomial coefficients for the angular distributions. No striking cross-section enhancement at ΣK threshold is observed, but there is evidence for a small cusp effect. A simple model which takes account of the ΣK channel provides a good fit to our data.
No description provided.
No description provided.
No description provided.
We have applied the Estabrooks and Martin analysis to a sample of 5279 events produced in the reactionπ+n ⇒ pρ0, and have made a density matrix study, including a positivity analysis, of theJ = 0, 1, 2density matrix in the f0 region, using a sample of 2385 events.
S-CHANNEL MOMENTS.
T-CHANNEL MOMENTS.
S-CHANNEL FRAME.
We have measured ρ0, ω (combined) and ϕ electroproduction over a range of virtual-photon four-momentum Q2 from 0.4 to 2.2 GeV2 and for photon energies ν from 2.7 to 8.6 GeV. We find that the slope of the t (momentum transfer) dependence of the ρ0 and ω forward peak decreases with increasing Q2 to less than half of the photoproduction slope.
The cross section for virtual photon are derived from E- P cross section bydividing on the virtual-photon flux factor.
Results are presented of a wire-spark-chamber spectrometer measurement of the differential cross section for π−p elastic scattering at 14.15 GeV/c. The region covered in the square of the four-momentum transfer, t, is 0.01<−t<0.78 (GeV/c)2. The cross section is found to obey very nearly a simple exponential t dependence with no evidence of structure. A fit to the data of the form dσdt∝exp(bt+ct2) on the range 0.05<−t<0.78 (GeV/c)2 (i.e., above the region affected by Coulomb scattering) yields b=8.26±0.10 (GeV/c)2 and c=1.01±0.17 (GeV/c)−4. Considering the results of previous measurements, b≃11 (GeV/c)−2 for −t<0.05 (GeV/c)2, a deviation from the simple exponential near −t≃0.05 (GeV/c)2 is indicated.
No description provided.
We have measured ep, eπ+, and eπ− coincidences for scattered electrons in the range Q2=0.4 to 2.2 GeV2 and W=2 to 4 GeV. We find (a) that vector-meson production decreases with Q2 more rapidly than does the total virtual-photon-plus-proton cross section, more rapidly even than the prediction of simple vector dominance, (b) that the slope of the t distribution in ρ and ω production becomes flatter with increasing Q2 and seems to be at least approximately a function of the single variable xρ=(Q2+mρ2)2Mν, (c) that the fraction of final states containing a proton decreases with increasing Q2, (d) that in the central region of longitudinal momenta the inclusive π+ yield seems to increase relative to the π− yield as Q2 increases, and (e) that the average transverse momentum of π− is greater than of π+ in the central region of longitudinal momenta.
No description provided.
The data with (C=Q=RHO+OMEGA) are obtained by excluding the contribution from RHO and OMEGA production.
No description provided.
The reactions of positive pions with protons yielding four charged particles and one or more neutrals have been studied, especially the reaction π+p→Δ++ω0→pπ+π+π−π0. The results presented in this paper were obtained from a 100 000-picture exposure of the Argonne-MURA 30-in. liquid hydrogen bubble chamber, with a beam of incident pions of 4.09−GeVc momentum. Comparisons have been made with corresponding results of other experiments at various incident beam momenta, and with the predictions of some theoretical models of the π+p interaction.
INCLUDING CORRECTIONS FOR BACKGROUND.
No description provided.
No description provided.
An investigation has been performed of some properties of Σ(1660) produced in the reaction K−p→Σ+(1660)π− at 2.87 GeV/c incident K− momentum. The decay modes observed for this state include Λ(1405)π and Σπ. The spin and parity are measured to be JP=32−. The differential cross section of the Λ(1405)π decay mode is sharply peaked in the forward direction, falling exponentially with a slope of 5.6 ± 0.7 (GeV/c)−2, while the slope for the Σ0π+ decay mode is 2.1 ± 0.4 (GeV/c)−2. The difference in the ratio of backward to total events for the two decay modes also suggests that two Σ(1660)'s exist.
No description provided.
No description provided.
A systematic analysis is presented on the reaction K + p → K ∗0 (890) Δ ++ for nine incident momenta between 4.6–16.0 GeV/ c . Cross sections, differential cross sections and vector meson single density matrix elements are given. As a function of energy, little if any change is observed in either the shapes of the differential cross sections or in the values of the density matrix elements. The data are interpreted in terms of current ideas on t -channel exchange mechanisms.
No description provided.
No description provided.
No description provided.
A recent spin-parity analysis of the π + π + π − system formed opposite a proton and a coherent deuteron by incident 13 GeV/ c 2 π + mesons, is extended to a three-pion mass of 1.9 GeV/ c . Relative proportions of the contributing partial waves are presented, from threshold, and the A 3 region is discussed in detail. Contrary to results with the (3 π ) − system, a change in phase is noted for the 2 − amplitude decaying to f 0 π + via am S-wave.
FOR A3+ DEFINED AS 2+ S-WAVE WITH 1.5 < M(3PI) < 1.8 GEV).
CONSTRAINT IMPLIES RHO(11) + RHO(1-1) = 0.
CONSTRAINT IMPLIES RHO(11) + RHO(1-1) = 0.
The missing mass spectrum opposite the proton in a 750 000 picture exposure, 13 GeV/ c π + p bubble chamber experiment, is investigated in two and four pion channels for structures observed or denied by boson spectrometers at the same energy in the reaction π − p→X − p.
BREIT-WIGNER FITS.
FOR 1.6 < M(4PI) < 1.8 GEV.
A spin and parity decomposition is presented of the (π+π+π−) final state formed opposite a proton by incident 13-GeV/c π+ mesons. The A3 enhancement is identified as the 2− amplitude decaying to f0π+ via an S wave. A change in relative phase is noted between the 2−S amplitude and the other principal contributions; this is not incompatible with analyses of the (3π)− system. The method employs the University of Illinois three-body partialwave analysis program.
A3+ DEFINED AS JP=2- S-WAVE.
We report here additional positive results of a search for muonless neutrino- and anti-neutrino-induced events using an enriched antineutrino beam and a muon identifier of relatively high geometric detection efficiency. The ratio of muonless to muon event rates is observed to be R=0.20±0.05. We observe no background derived from ordinary neutrino or antineutrino interactions that is capable of explaining the muonless signal.
No description provided.
Relative rates for deep inelastic neutrino and antineutrino scattering without a finalstate muon have been measured. For neutrinos the result is Rν=σ(νμ+nucleon→νμ+hadrons)σ(νμ+nucleon→μ−+hadrons)=0.11±0.05. The corresponding ratio for antineutrinos is Rν¯=0.32±0.09.
No description provided.
Total cross sections of π± and K± on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. All of the cross sections rise with increasing momentum.
No description provided.
PARTICLE-ANTIPARTICLE CROSS SECTION DIFFERENCES - SOME COMMON ERRORS CANCEL.
Proton and antiproton total cross sections on protons and deuterons have been measured at 50, 100, 150, and 200 GeV/c. The proton cross sections rise with increasing momentum. Antiproton cross sections fall with increasing momentum, but the rate of fall decreases between 50 and 150 GeV/c, and from 150 to 200 GeV/c there is little change in cross section.
No description provided.
ANTIPARTICLE-PARTICLE CROSS SECTION DIFFERENCES.
We have done a JP analysis of the low-mass π+ω system, using the reaction π+p→π+ωp at 7.1 GeV/c. We find that the B resonance cannot be JP=0− and must belong to the unnatural-parity series (1+, 2−, 3+,...), regardless of the amount of interference between the B and the background. If we assume that the B does not interfere with the background, we find that all JP states for the resonance are rejected except for 1+. Even if interference effects are allowed in the analysis, a good fit with reasonable parameters is obtained only with the 1+ hypothesis for the B meson. In an appendix, we give relevant theoretical formulas appropriate for a πω system with any number of spin-parity states and arbitrary degrees of interference among them.
TAKING INTO ACCOUNT 0- AND 1+ SMOOTH BACKGROUND UNDER THE B MESON. EVENTS WITH 1.08 < M(PI+ OMEGA) < 1.38 GEV.
The experimental upper limit for the diffractive photoproduction of the ψ(3105) is 29 nb, with 90% confidence, at an average photon energy of 18.2 GeV.
No description provided.
From a large-statistics π+p experiment at 7.1 GeV/c, data are presented on the reactions π+p→ρ0Δ++(1238) and π+p→ωΔ++(1238). Cross sections, differential cross sections, and vector-meson single-density-matrix elements are presented and a general comparison of the production properties of the two reactions is given. In addition to (ρ,ω)Δ++(1238) production there is also strong evidence for production of a π+p enhancement with mass ∼ 1880 MeV, Γ∼200 MeV, and J≥72 produced in association with the ρ and ω resonances. Detailed properties of this structure are presented and its production mechanism is compared with that of the corresponding Δ(1238) reactions. This state is also observed in the reaction K+p→K*0(890)Δ++(1880) at 12.0 GeV/c, for which data are also presented.
STATISTICAL ERRORS ONLY.
No description provided.
JACKSON FRAME.
We have measured the inclusive cross sections for γ, Ks0, Λ, and Λ¯ production in π+p and pp interactions at 100 GeV/c and compared various inclusive distributions of the produced γ and Ks0.
No description provided.
No description provided.
No description provided.
Strong evidence is presented for quasi-two-body production of a π + p enhancement with mass 1881±6MeV and width 219±23MeV, recoiling off vector mesons ϱ O and ω from π + p interactions at 7.1 GeV/ c and K * o (890) from K + p interactions at 12 GeV/ c . The most probable J P assignment for this object is 7/2 + , making it a likely candidate for the Regge recurrence of Δ(1236).
JACKSON FRAME.
JACKSON FRAME.
A partial wave analysis of the reaction π + n → π + π − π 0 p yields an A 0 2 production cross section of 225 ± 30μb for momentum transfer squared < 1 (GeV/ c ) 2 ; the differential cross-section and density matrix are presented and compared with ω 0 production in the light of theoretical models.
Axis error includes +- 10/10 contribution.
ASSUMING NO POPULATION OF HELICITY 2 DENSITY MATRIX ELEMENTS IN T-CHANNEL FRAME. THIS MM = 1+, 1-, 2+, 2- NOTATION REFERS TO THAT SUM OR DIFFERENCE OF HELICITY M DENSITY MATRIX ELEMENTS CORRESPONDING ASYMPTOTICALLY TO NATURAL (+) OR UNNATURAL (-) PARITY EXCHANGE.
Inclusive Δ++(1236) production in π+p and pp interactions is consistent with one-pion exchange. The average charged multiplicity recoiling from the Δ++ is studied as a function of missing mass, M2, for both interactions.
No description provided.
No description provided.
New measurements are reported of total cross sections for π ± , K ± , p and p on protons and deuterons at 11 momenta between 23 and 280 GeV/ c .
No description provided.
No description provided.
No description provided.
Results are presented on the topological cross sections obtained for antiproton-proton interactions from an exposure of the Fermilab 30-inch bubble chamber to a 100 GeV/ c negative beam enriched in p 's. The p p inelastic cross section is found to be σ inel = 34.6 ± 0.4 mb, and the average inelastic charged particle multiplicity to be 〈 n 〉 = 6.74 ± 0.05.
ERRORS ARE STATISTICAL ONLY EXCEPT FOR 2-PRONG CROSS-SECTIONS.
EXPONENTIAL FIT TO ELASTIC T DISTRIBUTION TO CORRECT FOR AN APPARENT LOSS OF EVENTS AT SMALL -T.
MOMENTS OF 100 GEV/C AP P MULTIPLICITY DISTRIBUTION.
We determine the ratio of the partial decay width for ψ(3684)→μ+μ− to that for the cascade decay ψ(3684)→ψ(3095)+X to be (1.4 ± 0.3)% and, by direct observation of associated charged particles and γ rays, find the ratio of the partial decay width for ψ(3684)→ψ(3095)+π0π0 to that for ψ(3684)→ψ(3095)+π+π− to be 0.64 ± 0.15.
Axis error includes +- 20/20 contribution (UNKNOWN SYSTEMATICAL ERRORDECAY-BR(BRN=J/PSI(3097) --> MU+ MU-, BR=?, C=FOLDED)).
Axis error includes +- 20/20 contribution (UNKNOWN SYSTEMATICAL ERRORDECAY-BR(BRN=J/PSI(3097) --> MU+ MU-, BR=?, C=FOLDED)).
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