Anthony, P.L.
DSIG/DT
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Photoproduction of the omega meson on the proton at large momentum transfer.

The CLAS collaboration Battaglieri, M. ; Brunoldi, M. ; De Vita, R. ; et al.
Phys.Rev.Lett. 90 (2003) 022002, 2003.
Inspire Record 599053 DOI 10.17182/hepdata.19351

The differential cross section, $d\sigma/dt$ for $\omega$ meson exclusive photoproduction on the proton above the resonance region ($2.6<W<2.9$ GeV) was measured up to a momentum transfer $-t = 5$ GeV$^2$ using the CLAS detector at Jefferson Laboratory. The $\omega$ channel was identified by detecting a proton and $\pi^+$ in the final state and using the missing mass technique. While the low momentum transfer region shows the typical diffractive pattern expected from Pomeron and Reggeon exchange, at large $-t$ the differential cross section has a flat behavior. This feature can be explained by introducing quark interchange processes in addition to the QCD-inspired two-gluon exchange.

4 data tables
Table 1

Differential cross section in the energy region 3.20 to 3.38 GeV.

Table 2

Differential cross section in the energy region 3.38 to 3.56 GeV.

Table 3

Differential cross section in the energy region 3.56 to 3.74 GeV.

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Exclusive electroproduction of Phi mesons at 4.2-GeV.

The CLAS collaboration Lukashin, K. ; Smith, E.S. ; Adams, G.S. ; et al.
Phys.Rev.C 64 (2001) 059901, 2001.
Inspire Record 552246 DOI 10.17182/hepdata.38589

We studied the exclusive reaction e p --> e' p' phi using the phi --> K^+ K^- decay mode. The data were collected using a 4.2 GeV incident electron beam and the CLAS detector at Jefferson Lab. Our experiment covers the range in Q^2 from 0.7 to 2.2 GeV^2, and W from 2.0 to 2.6 GeV. Taken together with all previous data, we find a consistent picture of phi production on the proton. Our measurement shows the expected decrease of the t-slope with the vector meson formation time c Delta tau below 2 fm. At = 0.6 fm, we measure b_phi = 2.27 +- 0.42 GeV^-2. The cross section dependence on W as W^{0.2+-0.1} at Q^2 = 1.3 GeV^2 was determined by comparison with phi production at HERA after correcting for threshold effects. This is the same dependence as observed in photoproduction.

3 data tables
Table 1

Slope of the DSIG/DT distribution in different Q**2 regions.

Table 2

Cross section as a function of Q**2 and W.

Table 3

The differential cross section for exclusive PHI electroproduction off the photon, (TP=T-TMIN).


Photoproduction of Phi(1020) mesons on the proton at large momentum transfer.

The CLAS collaboration Anciant, E. ; Auger, T. ; Audit, G. ; et al.
Phys.Rev.Lett. 85 (2000) 4682-4686, 2000.
Inspire Record 528835 DOI 10.17182/hepdata.19491

The cross section for $\phi$ meson photoproduction on the proton has been measured for the first time up to a four-momentum transfer -t = 4 GeV^2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. At low four-momentum transfer, the differential cross section is well described by Pomeron exchange. At large four-momentum transfer, above -t = 1.8 GeV^2, the data support a model where the Pomeron is resolved into its simplest component, two gluons, which may couple to any quark in the proton and in the $\phi$.

1 data table
Table 1

The differential PHI photoproduction cross section. The errors shown are the quadratic sum of the statistics and the systematic uncertainties which include 3 PCT for normalization, 5 PCT for acceptance and 5-15 PCT for background subtraction.


The Real Part of the Proton - anti-Proton Elastic Scattering Amplitude at the Center-Of-Mass Energy of 546-GeV

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 198 (1987) 583, 1987.
Inspire Record 249671 DOI 10.17182/hepdata.30077

Proton-antiproton elastic scattering was measured at the CERN SPS Collider at the centr-of-mass energy s =546 GeV in the Coulomb interference region. The data provide information on the phase of the hadronic amplitude in the forward direction. The conventional analysis gives for the ratio ϱ of the real to the imaginary part of the hadronic amplitude the result ϱ =0.24±0.04.

2 data tables
Table 1

Axis error includes +- 0.025/0.025 contribution (Normalisation was fixed using a previous UA4 measurement of the total cross section: sig(name=tot)*(1 + alpha**2)).

Table 2

Best estimate of alpha(rho).


The Cross-section of Diffraction Dissociation at the {CERN} {SPS} Collider

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 186 (1987) 227-232, 1987.
Inspire Record 235895 DOI 10.17182/hepdata.30212

Single diffraction dissociation was measured in the reaction p¯p→p¯X at the centre-of-mass energy √ s = 546 GeV. The mass M of the system X was deduced from the pseudorapidity distribution of the observed charged tracks. The cross section of single diffraction dissociation for M 2 /s⩽0.05isσ sd =9.4 ± 0.7 mb. Comparison to the ISR data shows that σ sd increases with energy less fast than the total and the elastic cross sections.

1 data table
Table 1

No description provided.


Large T Elastic Scattering at the {CERN} {SPS} Collider at $\sqrt{s}=630$-{GeV}

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 171 (1986) 142-144, 1986.
Inspire Record 227143 DOI 10.17182/hepdata.30263

Proton-antiproton elastic scattering was measured at the centre-of-mass energy s = 630 GeV in the four-momentum transfer range 0.7 ⩽ − t ⩽ 2.2 GeV 2 . The new data confirm our previous results at s = 546 GeV on the presence of a break in the t -distribution at − t ≃ 0.9 GeV 2 which is followed by a shoulder, and extend the momentum transfer range to larger values. The t -dependence of the differential cross section beyond the break is discussed.

1 data table
Table 1

Errors contain statistics and acceptance uncertainty.


Elastic Scattering at the {CERN} {SPS} Collider Up to a Four Momentum Transfer of 1.55-{GeV}**2

The UA4 collaboration Bozzo, M. ; Braccini, P.L. ; Carbonara, F. ; et al.
Phys.Lett.B 155 (1985) 197-202, 1985.
Inspire Record 213385 DOI 10.17182/hepdata.30410

Proton-antiproton elastic scattering was measured at the center-of-mass energy s =546 GeV in the four-momentum transfer range 0.45⩽−⩽1.55GeV 2 . The shape of the t -distribution is quite different from that observed in proton-proton scattering at the ISR. Rather than a dip-bump structure, a kink is present at − ≈0.9GeV 2 followed by a shoulder. The cross section at the second maximum is more than one order of magnitude higher than at the ISR.

1 data table
Table 1

No description provided.


Proton - Anti-proton Elastic Scattering at Four Momentum Transfer Up to 0.5-{GeV}**2 at the {CERN} {SPS} Collider

The UA4 collaboration Battiston, R. ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 127 (1983) 472, 1983.
Inspire Record 190657 DOI 10.17182/hepdata.30703

Proton-antiproton elastic scattering was measured at a centre of mass energy s = 540 GeV . In the four-momentum transfer range 0.21 < − t < 0.50 GeV 2 the t -distribution of about 7000 events is well represented by the exponential shape exp ( bt ) with slope parameter b = 13.7 ± 0.3 GeV −2 . A new measurement of the slope for − t < 0.19 GeV 2 confirms our earlier result, giving evidence for a change of slope of about 4 GeV −2 around − l ̷ ≈ 0.15 GeV 2 .

4 data tables
Table 1

NUMERICAL VALUES OF LOW T DATA GIVEN IN BOZZO 84. STATISTICAL ERRORS ONLY.

Table 2

NUMERICAL VALUES OF MEDIUM T DATA TAKEN FROM BOZZO 84. THESE ARE THE EARLIER (BATTISTON 83) VALUES RENORMALISED TO THE NEW LOW T DATA IN THE OVERLAP REGION. ERRORS ARE STATISTICAL ONLY.

Table 3

SLOPE VALUES FROM BATTISTON 83.

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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.


The Production of the Omega0 Meson in the Reaction pi+ d --> p (Spectator) p Omega0 at 4-GeV/c

Emms, M.J. ; Kinson, J.B. ; Stacey, B.J. ; et al.
Nucl.Phys.B 98 (1975) 1-28, 1975.
Inspire Record 100077 DOI 10.17182/hepdata.31856

The reaction π + n → ω 0 p has been studied at 4 GeV/ c giving a total cross section of 313 ± 26 μ b. The sample of about 3500 ω 0 events produced in the forward direction has been used to determine the differential cross section and the spin density matrix elements. The effective trajectory for unnatural parity exchange has been determined by a comparison of ϱ 00 d σ /d t at different energies. A comparison of ϱ 00 d σ /d t has been made with the similar data for ϱ 0 production in this experiment allowing π-B exchange degeneracy and ϱ-ω interference to be investigated. These methods result in an unnatural trajectory consistent with that expected for the B-meson. A further study of ϱ-ω interference has been made by comparing the reactions π + n → ω 0 p and π − p → ω 0 n at similar energies. Our results on ω and ϱ production are combined with data on K ∗0 and K ∗0 production at 4 GeV/ c and an SU(3) sum rule relating the production of these four mesons is shown to be satisfied.

13 data tables
Table 1

ASSUMING PREDOMINANTLY NUCLEON SPIN FLIP.

Table 2

No description provided.

Table 3

No description provided.

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