Lewis, G.M
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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.


OBSERVATION IN THE K+ K- SYSTEM OF A NEW STRUCTURE AT 2.2-GEV

The BARI-BONN-CERN-DARESBURY-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 154 (1979) 381-393, 1979.
Inspire Record 146574 DOI 10.17182/hepdata.34680

A sample of 56 909 events of the reaction π − p→K + K − n at 10 GeV/ c has been measured in the Omega Spectrometer at CERN. In the K + K − system, besides production of mesons in the S ∗ /φ, f 0 / A 2 , g /ω ∗ and h regions we observe a new structure at 2.20 GeV with a width of the order of 200 MeV.

1 data table
Table 1

BREIT-WIGNER RESONANCES PLUS SMOOTH BACKGROUND FITTED TO K+ K- MASS SPECTRUM. RESTRICTIVE T-CUTS TO ENHANCE THE X(2200) GIVE CONSISTENT RESULTS.


Observation of the Reaction pi- p --> anti-p d at 10-GeV/c and 16-GeV/c

The Bari-Bonn-CERN-Daresbury-Glasgow-Liverpool-Milan-Vienna collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 131 (1977) 54, 1977.
Inspire Record 5697 DOI 10.17182/hepdata.35222

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Production of phi and f' in 10-GeV/c K- p Interactions

The Bari-Bonn-CERN-Daresbury-Glasgow-Liverpool-Milan-Vienna collaboration Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.
Nucl.Phys.B 127 (1977) 384, 1977.
Inspire Record 5792 DOI 10.17182/hepdata.35286

None

4 data tables
Table 1

FOR THE FPRIME A PURE 2+ STATE IS ASSUMED AND ONLY JZ=+1,0,-1 CONTRIBUTIONS ARE CONSIDERED.

Table 2

No description provided.

Table 3

No description provided.

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PHOTOPRODUCTION OF POSITIVE PIONS FROM HYDROGEN NEAR THRESHOLD

Lewis, G.M. ; Azuma, R.E. ; Gabathuler, E. ; et al.
Phys.Rev. 125 (1962) 378, 1962.
Inspire Record 8499 DOI 10.17182/hepdata.26792

The variation of the differential cross section for π+ photoproduction from hydrogen, with γ-ray energy, has been examined at a laboratory angle of 58° to the γ-ray beam. A thin hydrogen target, and a counter system designed to eliminate random events, have been employed. Mean values for the differential cross section dσdΩ at γ-ray energies of 162, 168, 175, and 192 Mev are 5.42±0.38, 5.77±0.41, 6.74±0.47, and 8.22±0.58 μb/sr, respectively, where the error limits refer to relative values. The results substantiate the rising trend of the interaction quantity {(dσdΩ)(μ2pε)(1+ωM)2} near threshold, in accord with dispersion theory; and the absolute cross sections are compatible with a threshold value for a0+ near 20 μb/ steradian, consistent with findings in related pion work.

1 data table
Table 1

No description provided.


On the measurement of $\pi^{+}$ meson photoproduction from hydrogen near threshold

Lewis, G.M. ; Azuma, R.E. ;
Proc.Phys.Soc. 73 (1959) 873-880, 1959.
Inspire Record 1393355 DOI 10.17182/hepdata.26968

None

1 data table
Table 1

No description provided.


The total photon-proton cross-section for hadron production

Armstrong, T.A. ; Hogg, W.R. ; Lewis, G.M. ; et al.
Phys.Lett.B 34 (1971) 535-538, 1971.
Inspire Record 69289 DOI 10.17182/hepdata.28520

The total hadronic cross section, σ T has been measured for tagged γ -rays, using electron beams in the GeV range, and narrow energy bins. Preliminary data are given covering the γ -energy region 275 MeV-1850 MeV, where interesting structure characteristics are observed.

1 data table
Table 1

No description provided.


Measurements of the polarisation of the recoil proton in elastic electron proton scattering at q-squared=1.3, 1.5 and 1.9(gev/c)squared

Kirkman, H.C. ; Railton, R. ; Rutherglen, J.G. ; et al.
Phys.Lett.B 32 (1970) 519-522, 1970.
Inspire Record 63101 DOI 10.17182/hepdata.28765

An experiment has been carried out to determine the imaginary part of the two-photon exchange amplitude by measuring the polarisation of the recoil proton in elastic electron-proton scattering. The polirisation was found to be −0.006 ± 0.030 at q 2 = 1.3 (GeV/ c ) 2 , +0.052 ± 0.55 at 1.5 (GeV/ c ) 2 and +0.065 ± 0.087 at 1.9 (GeV/ c ) 2 .

1 data table
Table 1

No description provided.


AN AMPLITUDE ANALYSIS OF THE K+ K- SYSTEM PRODUCED IN THE REACTION PI- P ---> K+ K- N AT 10-GEV/C

The BARI-BONN-CERN-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Costa, G. ; Donald, R.A. ; Edwards, D.N. ; et al.
Nucl.Phys.B 175 (1980) 402-434, 1980.
Inspire Record 159739 DOI 10.17182/hepdata.34458

We present results on an amplitude analysis of the K + K − system produced in the reaction π − p→K + K − n from threshold up to 2.2 GeV. The branching ratios of f 0 and f' to K K have been determined. In the low mass region of the K K system the observation of an S-wave enhancement at 1.3 GeV and the interference of the f 0 -A 2 -f' mesons are studied. We observe a 3 − structure in the mass region of 1.7 GeV which is consistent with g 0 production. With this interpretation the branching ratio g→ K K has been determined. Evidence for a new structure in the J p = 2 + wave around 1.8 GeV with a width of ∼200 MeV is presented.

2 data tables
Table 1

HELICITY ZERO D-WAVE AMPLITUDE FITTED BY SUM OF BREIT-WIGNER RESONANCES. F 14 GIVES T-DEPENDENCE. ALSO EVIDENCE FOR 1.8 GEV STATE WITH 0.60 +- 0.13 MUB PRODUCTION CROSS SECTION.

Table 2

FROM HELICITY ZERO F-WAVE AMPLITUDE ASSUMING PREDOMINANTLY G(1680)0 PRODUCTION. F 16 GIVES T-DEPENDENCE.