Minguzzi-Ranzi, A.
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Test of S Channel Helicity Conservation in Inelastic $\rho^0$ Diffraction in 20-{GeV} Photoproduction

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.D 32 (1985) 2288, 1985.
Inspire Record 209692 DOI 10.17182/hepdata.23546

The reaction γp→ρfast0pπ+π− has been studied with the linearly polarized 20-GeV monochromatic photon beam at the SLAC Hybrid Facility to test the prediction of s-channel helicity conservation in inelastic diffraction for t’<0.4 (GeV/c)2. In a sample of 1934 events from this reaction, the ρ0 decay-angular distributions and spin-density-matrix elements are consistent with s-channel helicity conservation, the π+π− mass shape displays the same skewing as seen in the reaction γp→pπ+π−, and the pπ+π− mass distribution compares well and scales according to the vector dominance model with that produced in π±p→πfast±pπ+π−.

1 data table match query
Table 1

No description provided.


Measurement of total and partial photon proton cross-sections at 180-GeV center-of-mass energy

The ZEUS collaboration Derrick, M. ; Krakauer, D. ; Magill, S. ; et al.
Z.Phys.C 63 (1994) 391-408, 1994.
Inspire Record 372260 DOI 10.17182/hepdata.45055

Photon proton cross sections for elastic light vector meson production, σelνp, inelastic diffractive production, σndνp, non-diffractive production, σdνp, as well as the total cross section, σtotνp, have been measured at an average υp center of mass energy of 180 GeV with the ZEUS detector at HERA. The resulting values are σelνp = 18 ± 7 μb, σdνp = 33 ± 8 μb, σndνp = 91 ± 11 μb, and σtotνp 143 ± 17 μb, where the errors include statistical and systematic errors added in quadrature.

1 data table match query
Table 2

Errors contain both statistics and systematics.


OBSERVATION OF POLARIZATION IN DIFFRACTIVE DISSOCIATION p ---> LAMBDA0 K+ AT THE CERN ISR

Erhan, S. ; Hayes, K. ; Smith, A.M. ; et al.
62-65, 1984.
Inspire Record 202932 DOI 10.17182/hepdata.49652

None

1 data table match query
Table 1

No description provided.


Double diffraction dissociation at the Fermilab Tevatron collider

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 87 (2001) 141802, 2001.
Inspire Record 557212 DOI 10.17182/hepdata.42921

We present results from a measurement of double diffraction dissociation in $\bar pp$ collisions at the Fermilab Tevatron collider. The production cross section for events with a central pseudorapidity gap of width $\Delta\eta^0>3$ (overlapping $\eta=0$) is found to be $4.43\pm 0.02{(stat)}{\pm 1.18}{(syst) mb}$ [$3.42\pm 0.01{(stat)}{\pm 1.09}{(syst) mb}$] at $\sqrt{s}=1800$ [630] GeV. Our results are compared with previous measurements and with predictions based on Regge theory and factorization.

1 data table match query
Table 1

Cross sections for double diffractive production.


Some Three-Body Final States in K- p Reactions at 14.3-GeV/c

Wohl, C.G. ; Barloutaud, R. ; Borg, A. ; et al.
Nucl.Phys.B 132 (1978) 401-428, 1978.
Inspire Record 5385 DOI 10.17182/hepdata.35160

We present experimental results on a number of K − p reactions at 14.3 GeV/ c that have three bodies in the final state. The final states are K − ω p , K − π p , Λπ + π − , Λ K + K − , Λp p , K ∗ − ω p , Λ(1520) K + K − and Λ(1520) p p . Whenever, with one exception explained by the Zweig rule, there is a K − or a proton in the final state, there is a diffractive-like threshold enhancement in the mass spectrum of the two recoiling particles. These enhancements account for a large fraction of the events in all but the Λπ + π − final state, where they cannot occur, and which is dominated by resonance production. We find evidence for the Q 1 (1300) decaying into K − ω .

1 data table match query
Table 1

THE DIFFRACTION DISSOCIATION CROSS SECTIONS ARE FOR DIFFRACTIVE THRESHOLD ENHANCEMENTS IN THE TWO-BODY MASS SPECTRA (WITHIN 500 MEV CM ENERGY OF THRESHOLD).


Observation of diffractive W boson production at the Tevatron

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 78 (1997) 2698-2703, 1997.
Inspire Record 440095 DOI 10.17182/hepdata.42230

We report the first observation of diffractively produced W bosons. In a sample of W -> e nu events produced in p-barp collisions at sqrt{s}=1.8 TeV, we find an excess of events with a forward rapidity gap, which is attributed to diffraction. The probability that this excess is consistent with non-diffractive production is 1.1 10^{-4} (3.8 sigma). The relatively low fraction of W+Jet events observed within this excess implies that mainly quarks from the pomeron, which mediates diffraction, participate in W production. The diffractive to non-diffractive W production ratio is found to be R_W=(1.15 +/- 0.55)%.

1 data table match query
Table 1

No description provided.


Diffraction Dissociation of Photons on Hydrogen

Chapin, T.J. ; Cool, R.L. ; Goulianos, Konstantin A. ; et al.
Phys.Rev.D 31 (1985) 17-30, 1985.
Inspire Record 216071 DOI 10.17182/hepdata.4332

We report results from a measurement of the inclusive diffraction dissociation of photons on hydrogen, γp→Xp, in the range 754 GeV2. We test the finite-mass sum rule and, by comparing γp with π−p data obtained in the same apparatus, we test factorization.

14 data tables match query
Table 1

EXTRACTED ELASTIC CROSS SECTIONS.

Table 3

RESULTS OF EXPONENTIAL FITS TO ELASTIC CROSS SECTIONS.

Table 5

DIFFERENTIAL CROSS SECTIONS FOR INELASTIC EVENTS.

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Multiplicity structure of inclusive diffraction in pi+ p and K+ p interactions at 250-GeV/c

The EHS/NA22 collaboration Begalli, M. ; Botterweck, F. ; Boettcher, H. ; et al.
Z.Phys.C 55 (1992) 531-538, 1992.
Inspire Record 332787 DOI 10.17182/hepdata.14558

Results on the multiplicity structure of diffractively excited meson and proton systems in À+/K+p interactions at 250 GeV/c are presented for diffractive masses up to about 9 GeV. The energy dependence of the average charge multiplicity and the shape of the multiplicity distribution in terms of KNO-scaling and negative binomial distribution are investigated. The diffractive systems are compared toe+e−,lh and non-diffractivehh final states as suggested by modern approaches of the Pomeron-hadron collision. Systematic differences are found between diffractive meson and proton systems but also between diffraction and the reactions compared to.

4 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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THE STUDY OF DIFFRACTIVE DISSOCIATION IN THE REACTION anti-p p ---> anti-p p pi+ pi- AT 22.4-GeV/c

The Dubna-Alma Ata-Helsinki-Prague collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Dashian, N.B. ; et al.
JINR-E1-82-415, 1982.
Inspire Record 179201 DOI 10.17182/hepdata.9875

None

5 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Observation of Neutron Neutron Interactions with Double Diffraction Dissociation at the ISR

Mantovani, G.C. ; Cavalli-Sforza, M. ; Conta, C. ; et al.
Phys.Lett.B 65 (1976) 401-404, 1976.
Inspire Record 110581 DOI 10.17182/hepdata.27598

Neutron-neutron interactions have been observed at the CERN ISR with deutron colliding beams. The double - diffraction dissociation process →(p π p − )( pπ − ) has been measured with the Split Field Magnet at √ s = 26 GeV detecting all final state particles, including the two spectator protons. Mass and t distributions are presented and compared with corresponding spectra observed in single neutron diffraction in the same energy range with supporting evidence for factorization. The cross-section of the process is 11.5±2.8 μ b and can be directly related to the corresponding value for double diffraction dissociation of protons in the same energy range.

2 data tables match query
Table 1

ERROR IS MOSTLY SYSTEMATIC. DEUTERON CORRECTIONS APPLIED.

Table 2

No description provided.