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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

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Polarization of $\Lambda^\prime$s and $\bar{\Lambda}$-primes in $P P$, $\bar{P} P$, and $K^- P$ Interactions at 176-{GeV}/c

Gourlay, S.A. ; Melanson, H.L. ; Abolins, M.A. ; et al.
Phys.Rev.Lett. 56 (1986) 2244-2247, 1986.
Inspire Record 232417 DOI 10.17182/hepdata.20240

We have measured the polarization of Λ's in inclusive pp and K−p reactions and of Λ¯'s in p¯p interactions at a beam momentum of 176 GeV/c. Data were taken in the beam-fragmentation region with hyperon transverse momenta from 0.2 to 1.5 GeV/c. The P¯ produced Λ¯'s have the same magnitude and sign of polarization as the p-produced Λ's, whereas the Λ's from K−p interactions are more highly polarized and in the opposite direction.

3 data tables match query
Table 1

No description provided.

Table 2

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Table 3

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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

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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.


Angular Distribution for Eta-Meson Photoproduction from Hydrogen at 775-850 MeV

Bacci, C. ; Baldini-Celio, R. ; Mencuccini, C. ; et al.
Phys.Rev.Lett. 20 (1968) 571-574, 1968.
Inspire Record 944916 DOI 10.17182/hepdata.21723

None

3 data tables match query
Table 1

No description provided.

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No description provided.


Eta Photoproduction in the Region from Threshold to 940 MeV

Prepost, R. ; Lundquist, D. ; Quinn, D. ;
Phys.Rev.Lett. 18 (1967) 82-86, 1967.
Inspire Record 52317 DOI 10.17182/hepdata.21768

None

2 data tables match query
Table 1

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

Table 2

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


Some Recent Measurements of Proton Form Factors

Albrecht, W. ; Behrend, H.-J. ; Dorner, H. ; et al.
Phys.Rev.Lett. 18 (1967) 1014-1015, 1967.
Inspire Record 52298 DOI 10.17182/hepdata.21769

None

3 data tables match query
Table 1

No description provided.

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No description provided.


Sigma- production in high-energy proton interactions

Hungerbuehler, V. ; Majka, R. ; Marx, J.N. ; et al.
Phys.Rev.Lett. 30 (1973) 1234-1237, 1973.
Inspire Record 84497 DOI 10.17182/hepdata.21625

Momentum spectra for forward Σ− production on beryllium by protons of momentum 25.8 and 29.4 GeVc are presented. Data for the two primary proton momenta are compared for scaling behavior in the invariant cross section. In addition, the observed single-particle momentum distributions are compared with single-particle spectra from other inclusive reactions initiated by protons.

0 data tables match query