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Study of a $K^0_S K^0_S$ Plus Threshold Enhancement Observed in the Final States $\bar{p} p \to K^0_S K^0_S$ Pions at 700-{MeV}/$c$ to 760-{MeV}/$c$

Aguilar-Benitez, M. ; Cerrada, M. ; Gonzalez-Arroyo, Antonio ; et al.

Nucl.Phys.B 140 (1978) 73-108, 1978.

Inspire Record 130239 DOI 10.17182/hepdata.25444

An analysis of the K 0 K 0 system at threshold produced in the final states p p → K S 0 K S 0 ( n π) at 700–760 MeV/ c , is presented. A simultaneous fit to the ππ phase shifts and inelasticities and to the K S 0 K S 0 effective-mass distributions using parametrizations which take into account the analytical and unitarity properties of the I = 0 S-wave amplitudes is performed. The behaviour of the eigenphases and the unphysical Riemann sheet structure for different solutions is studied.

3 data tables

Table 1

No description provided.

Table 2

FIT TO RESONANCE PRODUCTION CHANNELS IN <KS KS PI+ PI-> FINAL STATE.

Table 3

FIT TO RESONANCE PRODUCTION CHANNELS IN <KS KS PI0> FINAL STATE.

On the construction of pion photoproduction amplitudes from experimental data

Alvarez-Estrada, R.F. ; Sanchez-Gomez, J.L. ;

Nucl.Phys.B 26 (1971) 433-444, 1971.

Inspire Record 68784 DOI 10.17182/hepdata.76722

New formulae for constructing the pion photoproduction amplitude J from experimental data are presented. The phase of J is expressed in terms of its zeroes in the energy plane, the particle poles and a dispersion integral over the modulus of J , the latter being given, except for a finite unphysical interval, in terms of differential cross sections and recoil nucleon polarizations. For γ p→ π + n at t ≈−0.870 μ 2 , where the unphysical-region contribution vanishes, the zeroes are found approximately, so that the phase of J can be uniquely determined from the experimental data.

3 data tables

Table 1

'1'.

Table 2

'1'.

Table 3

'1'.

Photoproduction of positive pions at backward angles in the energy range 1-3 gev

Alvarez, R.A. ; Cooperstein, G. ; Kalata, K. ; et al.

Phys.Rev.D 1 (1970) 1946-1960, 1970.

Inspire Record 61718 DOI 10.17182/hepdata.25170

The cross section for photoproduction of single π+ from hydrogen has been measured at laboratory angles of 110°, 127.5° and 152°, between 0.9- and 3.2-GeV incident photon energy. Measurements have been made with approximately 15% statistical accuracy at about 40 photon energies at each angle. The results agree well with the previous Caltech data of Thiessen. The cross section shows a rapid drop with increasing energy with superimposed bumps or shoulders corresponding to the N(1688), Δ(1920), and Δ(2420). A shallow minimum is observed at the N(2190) resonance.

1 data table

Table 1

No description provided.

Photoproduction of Positive Pions from Hydrogen at Energies Near the First Resonance

Alvarez, R.A. ;

Phys.Rev. 142 (1966) 957-971, 1966.

Inspire Record 944957 DOI 10.17182/hepdata.26683

Angular distributions for positive-pion photoproduction from liquid hydrogen have been measured at photon energies near 225, 250, 275, 300, and 350 MeV. These have been normalized to an absolute cross section near the peak of the first resonance, measured by means of a polyethylene-carbon subtraction using solid targets. The results are compared with results of previous experiments as well as several dispersion-theoretic predictions of the cross sections. The data can be fitted within the experimental and theoretical uncertainties by a theoretical calculation containing only the pion pole term and the transition to the P3,3 state due to the first resonance.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.