Bächler, J.
Proton-Proton Scattering
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DIJET PRODUCTION CROSS-SECTION AND FRAGMENTATION OF JETS PRODUCED IN P P COLLISIONS AT S**(1/2) = 63-GEV

The AXIAL FIELD SPECTROMETER collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 30 (1986) 27-43, 1986.
Inspire Record 221571 DOI 10.17182/hepdata.16017

We present stdies of events triggered on two high-pT jets, produced inpp collisions at the CERN Intersecting Storage Rings (ISR) at\(\sqrt s \)=63 GeV, using a large solid angle calorimeter. The cross-section for producing two jets is measured in the dijet mass range 17–50 GeV/c2. A high-statistics sample of dijet events, where each jet has transverse energy above 10 GeV, is used to study the structure of jets and the associated event. We find the longitudinal fragmentation function to be similar to that of jets emerging frome+e− collisions but considerably harder than that observed at the Super Proton Synchrotron (SPS)\(p\bar p\) Collider. A steepening of the fragmentation function is observed when increasing the jet energy. Studies of the charge distribution in jets show that these predominantly originate from fragmenting valence quarks. The transverse energy and particle flows are presented as functions of the azimuthal distance from the jet axis.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

FRAGMENTATION FUNCTION FOR ET(JET) > 10 GEV.


MEASUREMENT OF THE SPIN CORRELATION PARAMETER A(00NN) AND OF THE ANALYZING POWER FOR P P ELASTIC SCATTERING IN THE ENERGY RANGE FROM 0.5-GEV TO 0.8-GEV

Bystricky, J. ; Chaumette, P. ; Deregel, J. ; et al.
Nucl.Phys.B 262 (1985) 727-743, 1985.
Inspire Record 227731 DOI 10.17182/hepdata.33710

The spin correlation parameter A oonn and the analyzing powers A oono and A ooon were measured simultaneously, in the energy range 0.5–0.8 GeV and in the angular region 40°–80° CM. The experiment used the polarized proton beam of SATURNE II and the Saclay frozen spin polarized target.

15 data tables
Table 1

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MEASUREMENT OF THE SPIN CORRELATION PARAMETER A(00NN) FOR P P ELASTIC SCATTERING IN THE ENERGY RANGE FROM 0.83-GEV TO 1.1-GEV

Bystricky, J. ; Chaumette, P. ; Deregel, J. ; et al.
Nucl.Phys.B 262 (1985) 715-726, 1985.
Inspire Record 227730 DOI 10.17182/hepdata.33718

The spin correlation parameter A oonn (pp) and the analyzing power A oono (pp) have been measured in the angular region 45°< θ CM <90° at 0.834, 0.874, 0.934, 0.995 and 1.095 GeV beam kinetic energy using the SATURNE II polarized proton beam incident on the polarized proton target.

10 data tables
Table 1

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Table 2

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Table 3

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Observation of Longitudinal Event Structure in Proton Diffractive Dissociation at the {ISR}

The R608 collaboration Smith, A.M. ; Meritet, L. ; Reyrolle, M. ; et al.
Phys.Lett.B 167 (1986) 248-254, 1986.
Inspire Record 219984 DOI 10.17182/hepdata.30272

We study the internal structure of a forward-going pπ + π − π + π − system, with invariant mass in the range 2.5-4 GeV, produced through diffractive dissociation of a beam proton at the ISR. The shape of the system, as seen in its center-of-mass, deviates strongly from isotropic phase space and possesses, rather, a longitudinal structure with a major axis along the incoming proton direction. The final state proton momentum is aligned in the direction of the incoming proton, an effect which becomes more pronounced with increasing diffractive mass.

2 data tables
Table 1

Acceptance corrected distribution of momentum transfer to the diffractive (p-4pi) system. Data requested from authors.

Table 2

No description provided.


Direct Photon Pair Production From Pions and Protons at 200-{GeV}/$c$

The NA3 collaboration Badier, J. ; Bardadin-Otwinowska, M. ; Bemporad, C. ; et al.
Phys.Lett.B 164 (1985) 184-188, 1985.
Inspire Record 217947 DOI 10.17182/hepdata.30329

We present results from a direct photon pair search performed with the NA3 spectrometer, using incident positive and negative beams at 200 GeV/ c interacting with a carbon target. The experiment is sensitive to photons with p T >1.8 GeV / c and −0.4⩽y ∗ ⩽1.0 , one in each arm of the apparatus. A 3 standard deviation signal is seen in τ − and p interactions. The cross section is higher than the second order QCD calculations, but systematic errors are large.

1 data table
Table 1

No description provided.


Evidence for Pomeron Single Quark Interactions in Proton Diffraction at the {ISR}

The R608 collaboration Smith, A.M. ; Meritet, L. ; Reyrolle, M. ; et al.
Phys.Lett.B 163 (1985) 267-272, 1985.
Inspire Record 216801 DOI 10.17182/hepdata.30332

Measurements are presented of two exclusive diffractive reactions, pp → (Λ 0 φ 0 K + ) p and pp → (Λ 0 Λ 0 p)p , at √ s = 63 GeV . Pronounced correlations with the beam direction are observed (in the rest frame of the forward-going bracketed system) for those outgoing particles which contain the beam valence quarks. In each case there is a forward-Λ 0 in correlation with a backward K + or p, respectively. No such behavior is seen for the particles which do not contain beam valence quarks (φ 0 and Λ 0 , respectively) . Interpreted as examples of pomeron-proton scattering, these results constitute evidence that, for these final states, the pomeron interacts with a single valence quark and apparently back-scatters it. The subsequent hadronization leads to a longitudinal event structure.

3 data tables
Table 1

Cross sections for forward LAMBDA signal counting both arms of the p p interaction.

Table 2

Cross sections for forward LAMBDA signal counting both arms of the p p interaction.

Table 3

No description provided.


Test of {CP} Invariance in $\Lambda^0$ Decay

The R608 collaboration Chauvat, P. ; Erhan, S. ; Hayes, K. ; et al.
Phys.Lett.B 163 (1985) 273-276, 1985.
Inspire Record 216802 DOI 10.17182/hepdata.49640

In an experiment at the CERN intersecting storage rings with √ s = 31 GeV, we have measured αP , the product of asymmetry parameter and polarization, for Λ 0 's and Λ 0 's produced in p p and pp interactions, respectively. The ratio, (αP) Λ /(αP Λ = −1.04±0.29 , is consistent with the value −1, and constitutes the first test of CP invariance in Λ decay.

1 data table
Table 1

The ratio CONST/CONST is obtained under assumption of POL(LAMBDA) = POL(LAMBDABAR).


Inclusive $K^*$ and $\Sigma^*$ Production in 360-{GeV}/$c p p$ Interactions Using the European Hybrid Spectrometer

The EHS-RCBC collaboration Aziz, T. ; Bailly, J.L. ; Banerjee, S. ; et al.
Z.Phys.C 30 (1986) 381, 1986.
Inspire Record 216822 DOI 10.17182/hepdata.15884

We have studied the inclusive production of strange meson and baryon resonances in 360 GeV/cpp interactions. Cross sections forK*+(892) andK*−(892) are estimated to be 4.42±0.62 mb and 2.54±0.47 mb respectively and those for∑+(1385) and∑−(1385) are 0.67±0.11 mb and 0.26±0.07 mb respectively. Longitudinal and transverse momentum distributions forK*(892) and Σ(1385) are presented, as well as for their decay productsK0 and Λ. An estimation is given on theK*(1430) and∑*(1915) productions.

1 data table
Table 1

No description provided.


Measurements of Triple and Double Spin Parameters in Elastic $p p$ Scattering at 6-{GeV}/$c$

Auer, I.P. ; Chalmers, J. ; Colton, E. ; et al.
Phys.Rev.D 32 (1985) 1609, 1985.
Inspire Record 213562 DOI 10.17182/hepdata.23547

Toward the goal of experimentally determining the p-p elastic-scattering amplitudes at 6 GeV/c, we have measured a number of triple- and double-spin correlation parameters over the ‖t‖ range between 0.2 and 1.0 (GeV/c)2. These new data permit the first nucleon-nucleon amplitude determination in the multi-GeV energy range. Polarized beams from the Argonne Zero Gradient Synchrotron and polarized targets were utilized. The polarization of the recoil proton was measured with a carbon polarimeter. A total of 14 different spin observables were measured (five spin transfer, four depolarization, and five triple-spin correlation parameters). These have been combined with earlier results, resulting in a data set of typically 30 measurements of 20 different spin observables for each of six ‖t‖ values between 0.2 and 1.0 (GeV/c)2. A solution for the amplitudes has been found at each ‖t‖, and comparisons are presented with several different models. The spin-nonflip helicity amplitudes are found to be much larger than the spin-flip amplitudes.

2 data tables
Table 1

No description provided.

Table 2

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A comparison of direct photon, $\pi^0$, and $\eta$ production in $p\bar{p}$p and $pp$ interactions at the CERN ISR

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 158 (1985) 282-288, 1985.
Inspire Record 213984 DOI 10.17182/hepdata.30391

We have measured the production of direct photons, π 0 's, and η's in p p and pp collisions at √ s =53 GeV in the range 2≈ p T ≈6 GeV/ c for the central rapidity region | y | 0.4. No statistically significant difference between pp̄ and pp interactions is observed.

5 data tables
Table 1

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