HEPData Search

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 match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

Individual polarisation measurements.

More…

Observation of significant spin effects in hard collisions at 40-GeV/c

Apokin, V.D. ; Arestov, Yu.I. ; Astafev, O.V. ; et al.

Phys.Lett.B 243 (1990) 461-464, 1990.

Inspire Record 303587 DOI 10.17182/hepdata.29694

A single-spin asymmetry in the inclusive π 0 production at small x F was measured. In the experiment 40 GeV/c π − mesons were incident on transversely polarized protons and deutrons. An asymmetry of (40–50)% has been revealed in the hard scattering region.

1 data table match query

Table 1

No description provided.

Analyzing Power Measurements of Coulomb Nuclear Interference With the Polarized Proton and Anti-proton Beams at 185 GeV/c

The E581/704 collaboration Akchurin, N. ; Carey, David C. ; Coleman, R. ; et al.

Phys.Lett.B 229 (1989) 299-303, 1989.

Inspire Record 280476 DOI 10.17182/hepdata.29782

The analyzing power A N of proton-proton, proton-hydrocarbon, and antiproton-hydrocarbon, scattering in the Coulomb-nuclear interference region has been measured using thhe 185 GeV/ c Fermilab polarized-proton and -antiproton beams. The results are found to be consistent with theoretical predictions within statistical uncertainties.

3 data tables match query

Table 1

No description provided.

Table 2

Data from hydrocarbon target.

Table 3

Data from hydrocarbon target.

Polarization in the Reaction $\pi^-$ Polarized $p \to \pi^0 n$ at 40-{GeV}/$c$

Avvakumov, I.A. ; Apokin, V.D. ; Bagaturiya, Yu.Sh. ; et al.

Nucl.Phys.B 255 (1985) 253-272, 1985.

Inspire Record 206940 DOI 10.17182/hepdata.33791

The paper presents results on measuring the polarization in the reaction π − p→ π 0 n at 40 GeV/ c in the 4-momentum transfer range 0<| t |⩽2 (GeV/ c ) 2 . The results based on the statistics of about 2.2 million recorded events made it possible to observe a noticeable value and complex structure in the polarization behaviour up to | t |⩽2 (GeV/ c ) 2 .

2 data tables match query

Table 1

Table 2

Analyzing Power in Inclusive $\pi^+$ and $\pi^-$ Production at High $\chi_F$ with a 200 GeV Polarized Proton Beam

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

Phys.Lett.B 264 (1991) 462-466, 1991.

Inspire Record 315569 DOI 10.17182/hepdata.29360

The analyzing power in inclusive charged pion production has been measured using the 200 GeV Fermilab polarized proton beam. A striking dependence in x F is observed in which A N increases from 0 to 0.42 with increasing x F for the π + data and decreases from 0 to −0.38 with increasing x F for π − data. The kinematic range covered is 0.2⩽ x F ⩽0.9 and 0.2⩽ p T ⩽2.0 GeV / c . In a simple model our data indicate that at large x F the transverse spin of the proton is correlated with that of its quark constituents.

7 data tables match query

Table 1

Integrated over all PT.

Table 2

Integrated over all PT.

Table 3

No description provided.

More…

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 match query

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 match query

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.

More…

Date

Collaboration

Subject_areas

Phrases

Reactions

Observables

CM Energies (GeV)

Authors Reset

Polarization in Charge Exchange Reaction $\pi^- p \to \pi^0 n$ in Small Momentum Transfer Range at 40-{GeV}/$c$

Measurement of differential cross sections for charge exchange of $\pi^{-}$ mesons in carbon at 40 GeV/c

MEASUREMENT OF POLARIZATION IN THE pi- p ---> pi0, n, pi0 ---> 2 gamma REACTION AT 40-GeV/c WITH THE REGISTRATION OF ALL REACTION PRODUCTS

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

Observation of significant spin effects in hard collisions at 40-GeV/c

Analyzing Power Measurements of Coulomb Nuclear Interference With the Polarized Proton and Anti-proton Beams at 185 GeV/c

Polarization in the Reaction $\pi^-$ Polarized $p \to \pi^0 n$ at 40-{GeV}/$c$

Analyzing Power in Inclusive $\pi^+$ and $\pi^-$ Production at High $\chi_F$ with a 200 GeV Polarized Proton Beam

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