Brookes, G.R
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Total hadronic cross-section of gamma rays in hydrogen in the energy range 0.265-GeV to 4.215-GeV

Armstrong, T.A. ; Hogg, W.R. ; Lewis, G.M. ; et al.
Phys.Rev.D 5 (1972) 1640-1652, 1972.
Inspire Record 67298 DOI 10.17182/hepdata.22462

The total cross section of γ rays in hydrogen resulting in hadron production, σT, has been measured over the energy range 265-4215 MeV. A tagging system with narrow energy bins was employed. Structure in the resonance region followed by a steady fall with energy has been observed and the results are analyzed. The forward amplitude of γ-proton scattering is evaluated, and its behavior in the Argand diagram studied as a function of energy. The relationships of the measurements to Regge-pole theory and the vector-dominance model are detailed.

2 data tables
Table 1

No description provided.

Table 2

SPIN AVERAGED FORWARD COMPTON SCATTERING AMPLITUDE. IM(AMP) WAS CALCULATED VIA THE OPTICAL THEOREM FROM A SMOOTH FIT TO THE DATA, AND USED IN THE DISPERSION RELATION TO CALCULATE RE(AMP). AT THRESHOLD THE THOMSON AMPLITUDE IS -3.0 MUB*GEV.


Total hadronic photoabsorption cross-sections of nuclei for photons in the gev energy range

Brookes, G.R. ; Clough, A.S. ; Freeland, J.H. ; et al.
Phys.Rev.D 8 (1973) 2826-2836, 1973.
Inspire Record 93332 DOI 10.17182/hepdata.22018

The total hadronic photoabsorption cross sections of a number of nuclei (C, Al, Cu, Nb, Sn, Ta, Pb) have been studied in detail using a tagged photon beam over the energy range 1.7-4 GeV. The results are described, and compared with models of photoabsorption.

3 data tables
Table 1

STATISTICAL ERRORS. MEAN CROSS SECTIONS FOR EACH OF THE TWO ELECTRON BEAM ENERGIES OF 3.5 AND 4.6 GEV ARE ALSO GIVEN.

Table 2

A-EFFECTIVE/A, USING SIG(GAMMA P) = 137 MUB AND SIG(GAMMA N) = 126 MUB. STATISTICAL ERRORS.

Table 3

A-EFFECTIVE/A, USING SIG(GAMMA P) = 129 MUB AND SIG(GAMMA N) = 123 MUB. STATISTICAL ERRORS.


Hard Scattering and $\Delta - \Delta$ Exchange in Backward Photoproduction of $\Delta^{++} \pi^-$

Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Phys.Lett.B 98 (1981) 135-139, 1981.
Inspire Record 156090 DOI 10.17182/hepdata.27134

A tagged photon beam and multiparticle spectrometer have been used to measure the backward photoproduction process γp → Δ ++ π − . The energy dependence of the production cross section between 2.8 and 4.8 GeV is studied and found to exhibit shrinkage in excess of that expected for Δ σ dominance. An interpretation of the production mechanism in terms of an incoherent mixture of Δ σ exchange and a “hard scattering” contribution is presented.

1 data table
Table 1

No description provided.


Forward and Wide Angle Elastic $\phi$ - Meson Photoproduction on Hydrogen Between 2.8-{GeV} and 4.8-{GeV}

The LAMP2 Group collaboration Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Phys.Lett.B 79 (1978) 150-156, 1978.
Inspire Record 131968 DOI 10.17182/hepdata.27382

The s and t dependence of φ (1019) photoproduction has been investigated in the incident photon energy range 2.8 to to 4.8 GeV. Differential cross-sections and density matrix elements are presented for a t range extending from t min out to −1.3 (GeV/ c ) 2 . The results are discussed in terms discussed in terms of an effective Regge trajectory in the t -channel.

5 data tables
Table 1

DIFFERENTIAL CROSS SECTIONS AVERAGED OVER TWO RANGES OF INCIDENT PHOTON ENERGY.

Table 2

VARIATION OF SMALL -T DIFFERENTIAL CROSS SECTION WITH PHOTON ENERGY.

Table 3

INTERCEPT AND SLOPE FROM FITS TO D(SIG)/DT AT SMALL -T.

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INCLUSIVE pi0 PHOTOPRODUCTION AND THE QUARK - PARTON MODEL

The LAMP2 Group collaboration Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Phys.Lett.B 77 (1978) 233-239, 1978.
Inspire Record 129937 DOI 10.17182/hepdata.27429

We present measurements on the inclusive structure function for π 0 photoproduction for the incident photon energy range of 2.8–4.8 GeV. Comparisons are made with electroproduction data and it is found that the scaling behaviour already observed for finite q 2 continues to be valid at q 2 = 0.

1 data table
Table 1

No description provided.


Observation of the $\rho^-$prime (1600) in the Channel $\gamma p \to \pi^+ \pi^- p$

The Bonn-CERN-Ecole Poly-Glasgow-Lancaster-Manchester-Orsay-Paris-Rutherford-Sheffield collaboration Aston, D. ; Atkinson, M. ; Bailey, R. ; et al.
Phys.Lett.B 92 (1980) 215-218, 1980.
Inspire Record 152747 DOI 10.17182/hepdata.27241

A dipion enhancement of mass 1.59 GeV and width 0.23 GeV is observed in the channel γp→π + π − p. The spin-parity of the enhancement is consistent with being 1 − .

1 data table
Table 1

No description provided.


Backward Photoproduction of rho0 and f Between 2.8-GeV and 4.8-GeV

Clifft, R.W. ; Dainton, J.B. ; Gabathuler, E. ; et al.
Phys.Lett.B 64 (1976) 213-216, 1976.
Inspire Record 109693 DOI 10.17182/hepdata.27627

A measurement of backward photoproduction of charged pion pairs on protons is reported. The pion pair mass spectrum shows strong ϱ ° and f production. Data are presented on the u and s dependence for ϱ O and f, together with the decay polarisation for the ϱ O .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

AVERAGED OVER U RANGE OF EXPERIMENT. NO EVIDENCE FOR ANY LARGE S-WAVE CONTRIBUTION TO THE PI PI SYSTEM IN THE RHO0 MASS REGION (RHO(0S) < -0.03 +- 0.13). U CHANNEL FRAME: Z AXIS IN INCIDENT PROTON DIRECTION IN THE DIPION REST FRAME.


The $\rho^\prime$ (1600) in the Reaction $\gamma p \to \pi^+ \pi^- \pi^0 \pi^0 p$ at Photon Energies of 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 26 (1985) 499, 1985.
Inspire Record 202941 DOI 10.17182/hepdata.15774

The reactionγp→π+π−π0π0p (excludingωπ0 production) has been studied for photon energies in the range 20–70 GeV. A peak is seen in the 4π mass spectrum at ∼1.66 GeV with a width of ∼0.3 GeV which is identified with theρ′(1600). Maximum likelihood fits show that the peak is dominantly inρ±π∓π0 withB(ρ′→ρ0π0π0)/B(ρ′→ρ±π∓π0)<0.1. This indicates anI=1ρπ final-state interaction. However, no evidence is found for any resonant ρπ state such as anA1 orπ′.

2 data tables
Table 1

AFTER OMEGA EXCLUSION.

Table 2

ERROR IS DOMINANTLY SYSTEMATIC.


Diffractive Photoproduction of a $b_1 \pi$ System

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 34 (1987) 157, 1987.
Inspire Record 235576 DOI 10.17182/hepdata.15813

None

1 data table
Table 1

Systematic errors are at least 25 pct.


Inclusive Photoproduction of $\phi$, $K^*$ (890) and $K^*$ (1420) in the Photon Energy Range 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 30 (1986) 521, 1986.
Inspire Record 218609 DOI 10.17182/hepdata.15900

Inclusive photoproduction of ϕ,K*0(890),\(\bar K*^0 \) andK*0(1420),\(\bar K*^0 \) has been studied in γp collisions with photons of energy 20 to 70 GeV and in the range 0.1≦xF≦0.95 [0.4≦xF≦0.8 for the\(\mathop K\limits^{( - )} *\)(1420)],xF being the Feynman variable of the vector/tensor meson. The cross-sections for these processes, averaged over the photon energy range and integrated overxF are given. The inclusive ϕ production in the forward direction can be described quantitatively by a triple-Regge model calculation. The remaining ϕ production and the totalK*0(890) and\(\bar K*^0 \) production are consistent with a quark fusion picture.

1 data table
Table 1

No description provided.