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Measurement of pi-p Elastic Scattering at 180-degrees

Kormanyos, S.W. ; Krisch, A.D. ; O'Fallon, J.R. ; et al.

Phys.Rev. 164 (1967) 1661-1671, 1967.

Inspire Record 944948 DOI 10.17182/hepdata.51371

We have measured the differential cross section for π−p elastic scattering at 180° in steps of 0.10 GeV/c or less in the region P0=1.6 to 5.3 GeV/c. We detected elastic scattering events, from protons in a liquid H2 target, with a double spectrometer consisting of magnets and scintillation counters in coincidence. The incident π− beam was counted by scintillation counters. The cross section was found to have considerable structure. This may be interpreted as interference between the resonant amplitudes and the nonresonant or background amplitude. Very strong destructive interference occurs around P0=2.15 GeV/c, where the cross section drops almost two orders of magnitude in passing through the N*(2190). Another interesting feature of the data is a large narrow peak in the cross section at P0=5.12 GeV/c, providing firm evidence for the existence of a nucleon resonance with a mass of 3245±10 MeV. This N*(3245) has a full width of less than 35 MeV, which is about 1% of its mass. From this experiment we were able to determine the parity and the quantity χ(J+12) for each N* resonance, where χ is the elasticity and J is the spin of the resonance.

1 data table match query

Table 22

No description provided.

INCLUSIVE JET PRODUCTION AT S**(1/2) = 546-GeV

The UA1 collaboration Arnison, G. ; Allkofer, O.C. ; Astbury, A. ; et al.

CERN-EP-85-116, 1985.

Inspire Record 216597 DOI 10.17182/hepdata.50065

None

1 data table match query

Table 1

No description provided.

Charged $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV} and a Limit on D0 - Anti-d0 Mixing

Yamamoto, H. ; Atwood, W.B. ; Baillon, P. ; et al.

Phys.Rev.Lett. 54 (1985) 522-525, 1985.

Inspire Record 205132 DOI 10.17182/hepdata.20325

We have studied inclusive D*± production using the DELCO detector at PEP. Our technique involved kaon identification in the momentum range above 3.2 GeV/c using a threshold gas Čerenkov counter. This leads to a model-independent upper limit on D0−D¯0 mixing of 8.1% (90% confidence level). We also have measured the charm fragmentation function, which peaks at x≡PD*(Ebeam2−MD*2)12 of 0.56±0.06(stat.), and the total cross section for D* production, σ(D*±)=0.140±0.021(stat.)±0.032(syst.) nb (x>0.3, with radiative correction).

2 data tables match query

Table 1

No description provided.

Table 2

SYSTEMATIC ERROR DOES NOT INCLUDE THE UNCERTAINTY ON THE BRANCHING RATIOS USED.

Observation of a Narrow K anti-K State in J/psi Radiative Decays

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.

Phys.Rev.Lett. 56 (1986) 107, 1986.

Inspire Record 217856 DOI 10.17182/hepdata.20254

Evidence is presented for a narrow state, called ξ, in the decay modes J/ψ→γξ, ξ→K+K−, and ξ→KS0KS0. In the K+K− mode, the ξ has a mass of 2.230±0.006±0.014 GeV/c2, a width of Γ=0.026−0.016+0.020± 0.017 GeV/c2, a product branching ratio of (4.2−1.4+1.7±0.8)×10 −5, and a statistical significance of ∼4.5 standard deviations. In the KS0KS0 mode, it has a mass of 2.232±0.007±0.007 GeV/c2, a width of Γ=0.018−0.015+0.023± 0.010 GeV/c2, a product branching ratio of (3.1−1.3+1.6±0.7)×10 −5, and a statistical significance of ∼3.6 standard deviations. Limits on ξ decay to other final states are presented.

1 data table match query

Table 1

No description provided.

The Production of Massive Muon Pairs in $\pi^-$ Nucleus Collisions

Greenlee, H.B. ; Frisch, Henry J. ; Grosso-Pilcher, C. ; et al.

Phys.Rev.Lett. 55 (1985) 1555, 1985.

Inspire Record 17013 DOI 10.17182/hepdata.20316

We present measurements of the differential cross section for the production of massive muon pairs in 225-GeV/c π−-nucleus collisions. We have used the data between the ψ and ϒ resonances in the framework of the Drell-Yan quark-antiquark annihilation model to predict the behavior of the cross section in the high-mass (mμμ>11 GeV/c2) region. The data are consistent with this extrapolation provided that a QCD leading-logarithmic evolution is included in the structure functions.

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.

HIGH-ENERGY PHOTOMESON PRODUCTION FROM HYDROGEN VIA THE 'u CHANNEL'

Anderson, Robert L. ; Gustavson, D. ; Johnson, J.R. ; et al.

Phys.Rev.Lett. 21 (1968) 479-481, 1968.

Inspire Record 52639 DOI 10.17182/hepdata.21700

We have investigated the photoproduction process γ+p→π++n over a wide range of energies and u values at the Stanford Linear Accelerator Center (SLAC) accelerator. We also have investigated γ+p→π−+N*++ at one value of u and γ+p→K++Λ0, Σ0 at one u value and three energies. Our results for dσdu for the photoproduction of π+ mesons from hydrogen are roughly α2π of the corresponding cross sections for the elastic scattering of π− mesons from hydrogen. The u dependence of our cross sections is not dominated by nucleon exchange as it is in the case of π+p elastic scattering.

0 data tables match query

Differential Cross Sections in Eta Photoproduction from 0.8 to 1.45 GeV

Bloom, E.D. ; Heusch, C.A. ; Prescott, C.Y. ; et al.

Phys.Rev.Lett. 21 (1968) 1100-1103, 1968.

Inspire Record 54471 DOI 10.17182/hepdata.21721

The cross section for the process γp→pη was studied from 0.8- to 1.45-GeV incident photon energy at center-of-mass angles from 50 to 90°. The data cover a range of energies well beyond previous measurements. The results will aid in the study of I=12 nucleon isobars.

3 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

SINGLE pi+- AND K+ PHOTOPRODUCTION FROM COMPLEX NUCLEI AT 8-GeV AND 16-GeV

Boyarski, A. ; Diebold, Robert E. ; Ecklund, Stanley D. ; et al.

Phys.Rev.Lett. 23 (1969) 1343-1346, 1969.

Inspire Record 54879 DOI 10.17182/hepdata.21641

The reactions γA→π±A* have been studied at four-momentum transfers −t<~0.5 GeV2 for seven elements ranging from hydrogen to lead. Exclusion-principle suppression is clearly visible at small-momentum transfer. Neither the A dependence nor the energy dependence of the cross sections agrees with the predictions of the vector-dominance model. The ratio of π−π+ production requires equal spatial distributions for the protons and neutrons in nuclei. Some K+ data are also presented.

1 data table match query

Table 15

No description provided.