Amarian, M.
P P --> PI0 X
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Inclusive particle production in 400-GeV/c p p interactions

Aguilar-Benitez, M. ; Allison, W.W. W. ; Batalov, A.A. ; et al.
Z.Phys.C 50 (1991) 405-426, 1991.
Inspire Record 314091 DOI 10.17182/hepdata.1435

We report on a study of inclusive particle production in pp-interactions at 400 GeV/c. The data are based on 472 K reconstructed events recorded in the NA 27 experiment using the LEBC-EHS facility at CERN. The production cross sections are determined of pseudo scalar (π±,0, η andK±), scalar (f0(975)), vector (ρ±,0(770), ω(783), ϕ(1020),K*0(892), and\(\bar K^{ * 0} \)(892)), and tensorf0 mesons, of protons and antiprotons, and theΔ++,+,0(1232), and Λ(1520) baryon resonances in the forward hemisphere of the center of mass system, as well as longitudinal and transverse momentum distributions. The results are compared with predictions of the FRITIOF model and with other experimental data.

61 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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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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.


Large $\chi_F$ Spin Asymmetry in $\pi^0$ Production by 200 GeV Polarized Protons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.
Z.Phys.C 56 (1992) 181-184, 1992.
Inspire Record 314230 DOI 10.17182/hepdata.14557

The spin asymmetryAN for inclusive π0 production by 200-GeV transversely-polarized protons on a liquid hydrogen target has been measured at Fermilab over a wide range ofxF, with 0.5<pT<2 GeV/c. AtxF>0.3, the asymmetry rises with increasingxF and reaches a value ofAN=0.15±0.03 in the region 0.6<xF<0.8. This result provides new input regarding the question of the internal spin structure of transversely-polarized protons.

5 data tables
Table 1

No description provided.

Table 2

False asymmetry calculated for events with average beam polarization of zero.

Table 3

No description provided.

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High $p_T \gamma$ and $\pi^0$ Production, Inclusive and With a Recoil Hadronic Jet, in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Sov.J.Nucl.Phys. 51 (1990) 836-845, 1990.
Inspire Record 281284 DOI 10.17182/hepdata.48816

None

3 data tables
Table 1

Errors are combined statistical and systematic.

Table 2

Errors are combined statistical and systematic.

Table 3

Errors are combined statistical and systematic.


Analyzing Power Measurement in Inclusive $\pi^0$ Production at High $\chi_F$

Bonner, B.E. ; Buchanan, J.A. ; Carey, D.C. ; et al.
Phys.Rev.Lett. 61 (1988) 1918, 1988.
Inspire Record 269386 DOI 10.17182/hepdata.2928

The analyzing power AN in inclusive π0 production has been measured with use of the new 185-GeV/c Fermilab polarized proton beam. We obtain the value AN=0.10±0.03 for π0's in the kinematic region 0.2<xF<0.8 and 0.3<pT<1.2 GeV/c. In certain models of particle production this suggests that the spin of the proton is carried by its valence quarks.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Individual polarisation measurements.

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Production of High Transverse Momentum Prompt Photons and Neutral Pions in Proton Proton Interactions at 280-GeV/c

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Booth, P.S.L. ; et al.
Z.Phys.C 38 (1988) 371, 1988.
Inspire Record 252633 DOI 10.17182/hepdata.15647

The inclusive cross sections for production of prompt photons and π0s by 280 GeV/c protons incident on a liquid hydrogen target, have been measured forpT in the range 4.0 to 6.5 GeV/c and for |xF|<0.45. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed. Phenomenological fits to the π0 and prompt photon cross sections are given.

6 data tables
Table 1

Invariant cross section.

Table 2

No description provided.

Table 3

Invariant cross section.

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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 Measurement of $\pi^0$ Production at Large Transverse Momentum in $\pi^- p$, $\pi^+ p$ and $p p$ Collisions at 300-{GeV}/$c$

The NA24 collaboration De Marzo, C. ; De Palma, M. ; Favuzzi, C. ; et al.
Phys.Rev.D 36 (1987) 16, 1987.
Inspire Record 236249 DOI 10.17182/hepdata.23354

Cross sections for inclusive π0 production at large transverse momentum pT were measured in π−p, π+p, and pp collisions at 300 GeV/c. The cross-section ratio σ(π−p→π0X)/σ(π+p→π0X) was found to be consistent with unity in the pT region of 1 to 5 GeV/c. The cross-section ratio σ(π+p→π0X)/σ(pp→π0X) however is growing with increasing pT and increasing π0 c.m.-system rapidity in agreement with parton-model expectations, where the partons in the pions have on average higher momenta than in the proton.

1 data table
Table 1

THERE IS ALSO A 1 PCT UNCERTAINTY IN THE PT SCALE AND A 7 PCT UNCERTAINTY IN THE NORMALISATION.