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Single spin asymmetries and invariant cross-sections of the high transverse momentum inclusive pi0 production in 200-GeV/c p p and anti-p p interactions

The FNAL E704 collaboration Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.

Phys.Rev.D 53 (1996) 4747-4755, 1996.

Inspire Record 382392 DOI 10.17182/hepdata.40544

The π0 inclusive and semi-inclusive, single-spin asymmetries have been measured using transversely polarized, 200-GeV/c proton and antiproton beams colliding with an unpolarized hydrogen target. The measured asymmetries are consistent with zero within the experimental uncertainties for the kinematic region -0.15<xF<+0.15 and 1<pT<4.5 GeV/c. Improvements in the data analysis showed that our earlier large asymmetries at pT≳3 GeV/c were not correct. These data indicate that PQCD expectations seem confirmed and the higher-twist contribution to the single-spin asymmetry in π0 production at xF=0 is not large. Additional evidence for such a conclusion comes from the measurement of a semi-inclusive π0 asymmetry, where associated charged particles are detected opposite to the π0 azimuthal direction. This experiment also provides high-statistics data on the inclusive π0 cross sections for pp and p¯p collisions at √s≊19.4 GeV. © 1996 The American Physical Society.

3 data tables

Table 1

No description provided.

Table 2

Pure inclusive reaction.

Table 3

Semi-inclusive reaction where at least on associated charged particle is produced at (180+-30) degrees relative to the pi0.

High $\chi_t$ Single Spin Asymmetry in $\pi^0$ and $\eta$ Production at $\chi_F$ = 0 by 200 GeV Polarized Antiprotons and Protons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.

Phys.Lett.B 276 (1992) 531-535, 1992.

Inspire Record 314231 DOI 10.17182/hepdata.29252

A measurement of the single-spin asymmetry A N in p↑ + p→ π 0 + X at 200 GeV with x F = 0 shows a transition in the production process from a “ low -x T ” regime with A N = 0, through an intermediate region of negative asymmetry, to a “ high -x T ” regime with A N > 0.3. This transition occurs at x T ≈ 0.4 and is consistent with x T -scaling of A N in pion production using polarized beams or targets from √− s =5.2 to 19.4 GeV. Results for A N in η production by polarized protons and in π 0 production by polarized antiprotons are also presented.

3 data tables

Table 1

Statistical errors only.

Table 2

Statistical errors only.

Table 3

Statistical errors only.

First Results for the Two Spin Parameter $A_{LL}$ in $\pi^0$ Production by 200-GeV Polarized Protons and Antiprotons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.

Phys.Lett.B 261 (1991) 197-200, 1991.

Inspire Record 314233 DOI 10.17182/hepdata.29385

The two-spin parameter A LL in inclusive π 0 productionby longitudinally-polarized protons and antiprotons on a longitudinally-polarized proton target has been measured at the 200 GeV Fermilab spin physics facility, for π 0 's at x F =0 with 1⩽ p t ⩽3 GeV/ c . The results exclude, at the 95% confidence level, values of A LL (pp) > 0.1 and < − 0.1 for π 0 's produced by protons, and values of A LL ( p p) > 0.1 and < −0.2 for incident antiprotons. The relevance of A LL (pp) for the gluon spin density is discussed. The data are in good agreement with “conventional”, small or zero, gluon polarization.

1 data table

Table 1

No description provided.

Comparison of Spin Asymmetries and Cross Sections in $\pi^0$ Production by 200 GeV Polarized Antiprotons and Protons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.

Phys.Lett.B 261 (1991) 201-206, 1991.

Inspire Record 314232 DOI 10.17182/hepdata.29396

None

4 data tables

Table 1

No description provided.

Table 2

P P data are taken from Adams et al, Fermilab-Pub-91/13-E.

Table 3

Ratio of the spin averaged invariant cross section for PI0 production in p p and pbar p interactions.

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Direct Photon Production in $\bar{p} p$ Collisions at $\sqrt{s}=630$-{GeV}

The UA2 collaboration Ansari, R. ; Bagnaia, P. ; Banner, M. ; et al.

Z.Phys.C 41 (1988) 395, 1988.

Inspire Record 264998 DOI 10.17182/hepdata.15558

A measurement of the direct production of photons with high transverse momentum from$\bar pp$ collisions at$\sqrt s= 630$ GeV is presented. The structure of events containing a high transverse momentum photon is studied. The results support predictions from QCD theory.

5 data tables

Table 1

The last data point is an average over the interval 60-100 GeV in which 5 events are found.

Table 2

No description provided.

Table 3

No description provided.

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A Measurement of the Inclusive $\pi^0$ and $\eta$ Production Cross-sections at High $p_T$ in $p \bar{p}$ and $p p$ Collisions at $\sqrt{s}=24$.3-{GeV}

The UA6 & CERN-Lausanne-Michigan-Rockefeller collaborations Antille, J. ; Baumann, S. ; Bernasconi, A. ; et al.

Phys.Lett.B 194 (1987) 568, 1987.

Inspire Record 247579 DOI 10.17182/hepdata.30119

Inclusive π 0 and η production at large transverse momentum were studied in both p̄p and pp interactions at √ s = 24.3 GeV. The experiment was performed using an internal molecular hydrogen gas jet target in the CERN SPS collider. No significant differences between production in p̄p and pp were observed in the transverse momentum range 2.5 < P T < 5.1 GeV/ c .

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Particle Production in the Transverse Momentum Range Between 0.25-{GeV}/$c$ and 40-{GeV}/$c$ at the {CERN} S $p \bar{p}$ S Collider

The UA2 & Bern-CERN-Copenhagen-Orsay-Pavia-Saclay collaborations Banner, M. ; Bloch, Ph. ; Bonaudi, F. ; et al.

Z.Phys.C 27 (1985) 329, 1985.

Inspire Record 206017 DOI 10.17182/hepdata.16075

Inclusive particle production cross-sections have been measured at the$Sp\bar pS$ collider using the UA2 detector in various ranges of transverse momentum (PT) and pseudo-rapidity (η). Cross-section measurements are presented forπ0 production (PT≦15 GeV/c, |η|≦0.85 andPT≦40 GeV/c, 1.0≦|η|≦1.8), for η meson production (3≦PT≦6 GeV/c, |η|≦0.85) and for charged particle production (PT≦10 GeV/c, 1.0≦|η|≦1.8). Results are compared with the predictions of QCD calculations.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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INCLUSIVE gamma PRODUCTION IN anti-p p INTERACTIONS AT 12-GeV/c

Chakrabarti, S. ; Banerjee, S. ; Ganguli, S.N. ; et al.

Z.Phys.C 27 (1985) 1, 1985.

Inspire Record 202797 DOI 10.17182/hepdata.16116

The inclusive production of photons in$\bar pp$ interactions has been studied at incident momentum of 12 GeV/c. Topological cross section has been presented and KNO distribution for$\bar pp$ interactions has been studied. Inclusive cross section for γ production has been measured to be 149.5±8.8 mb. Bulk of these photons come from π0 decays whose cross section has been evaluated independently to be 60.4±7.9 mb. Signals of η and ω have been seen in γγ and π+π-π0 decay modes and their inclusive cross sections have been estimated to be 14.9±8.8 mb and 14.6±7.0 mb respectively. Results on average multiplicities of γ and two particle correlation parameters are presented. Neutral pions seem to be more strongly correlated than the charged pions. The inclusive distributions of the Feynmanx andpT/2 of the photons are compared with expectation from charged pions on the basis of charge independence. Energy dependence of the normalised invariant distributions has been studied. The distribution of the scaling variablez of photons ine+e− and$\bar pp$ interactions has been compared.

8 data tables

Table 1

Table 2

Table 3

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GENERAL FEATURES OF ANTI-P P INTERACTIONS AT 7.3-GEV/C

Patel, G.D. ; Johnson, P. ; Mason, P. ; et al.

Z.Phys.C 12 (1982) 189-202, 1982.

Inspire Record 179888 DOI 10.17182/hepdata.2239

Absolute inclusive cross sections for$\bar pp$ interactions at 7.3 GeV/c are given. The data cover prong cross sections,V0, γ production and inclusive charged particle (p/π) production. Separation has been made into annihilation and non-annihilation components. Inclusive π+, π− production in the processes of$\bar pp$ annihilation and non-annihilation are compared with simple quark models.

26 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

ANNIHILATION AND NON-ANNIHILATION TOPOLOGICAL CROSS SECTIONS.

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Single spin asymmetries and invariant cross-sections of the high transverse momentum inclusive pi0 production in 200-GeV/c p p and anti-p p interactions

High $\chi_t$ Single Spin Asymmetry in $\pi^0$ and $\eta$ Production at $\chi_F$ = 0 by 200 GeV Polarized Antiprotons and Protons

First Results for the Two Spin Parameter $A_{LL}$ in $\pi^0$ Production by 200-GeV Polarized Protons and Antiprotons

Comparison of Spin Asymmetries and Cross Sections in $\pi^0$ Production by 200 GeV Polarized Antiprotons and Protons

Direct Photon Production in $\bar{p} p$ Collisions at $\sqrt{s}=630$-{GeV}

A Measurement of the Inclusive $\pi^0$ and $\eta$ Production Cross-sections at High $p_T$ in $p \bar{p}$ and $p p$ Collisions at $\sqrt{s}=24$.3-{GeV}

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

Inclusive Particle Production in the Transverse Momentum Range Between 0.25-{GeV}/$c$ and 40-{GeV}/$c$ at the {CERN} S $p \bar{p}$ S Collider

INCLUSIVE gamma PRODUCTION IN anti-p p INTERACTIONS AT 12-GeV/c

GENERAL FEATURES OF ANTI-P P INTERACTIONS AT 7.3-GEV/C