HEPData Search

We present density-matrix elements and single-spin correlations for the reaction p↑p→pπ+n at 3, 4, 6, and 11.75 GeV/c, using both longitudinal and transverse beam polarizations. For small momentum transfers, the spin correlations are mainly due to off-shell π+p elastic scattering, while for larger t there are large polarization effects associated with the production dynamics for p↑p→Δ++n. Comparison of longitudinal and transverse polarization correlations suggests that the Δ++-production spin effects are due mainly to unnatural-parity exchanges. We present a model-dependent amplitude analysis, and extract the energy dependence of the natural- and unnatural-parity-exchange contributions.

36 data tables

Table 1

Unpolarized cross sections.

Table 2

Unpolarized cross sections.

Table 3

Unpolarized cross sections.

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Comparison of Exclusive Reactions at Large $T$

Baller, B.R. ; Blazey, G.C. ; Courant, H. ; et al.

Phys.Rev.Lett. 60 (1988) 1118-1121, 1988.

Inspire Record 264273 DOI 10.17182/hepdata.3063

Cross sections or upper limits are reported for 12 meson-baryon and two baryon-baryon reactions for an incident momentum of 9.9 GeV/c, near 90° c.m.: π±p→pπ±,pp±,π+°±,K+Σ±, (Λ0/Σ0)K0; K±p→pK±; p±p→pp. By studying the flavor dependence of the different reactions, we have been able to isolate the quark-interchange mechanism as dominant over gluon exchange and quark-antiquark annihilation.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Double Statistical Tensors for the Reaction p p --> Delta++ Delta0 in a Range of 5-GeV/c to 25-GeV/c

The Genoa-World Proton-Proton collaboration Caso, C. ; Girimonte, L. ;

Nuovo Cim.A 33 (1976) 671, 1976.

Inspire Record 3097 DOI 10.17182/hepdata.9285

The joint decay distribution for the reaction pp → Δ++Δ0 is described in terms of double statistical tensors, which were determined in a model-independent way using the World Proton-Proton Data Summary Tape. The statistical tensors were calculated in nontransversal and in transversal reference frames. The results are presented as a function of the proton laboratory momentum, covering the range from 5 to 25 GeV/c. Due to a lack of statistics, the values as a function of the four-momentum transfers were obtained by adding together data from different energies. Results are again given in several reference frames.

9 data tables

Table 1

CONTENT OF THE WORLD PROTON PROTON DATA SUMMARY TAPE.

Table 2

STATISTICAL TENSORS IN THE JACKSON NONTRANSVERSAL FRAME.

Table 3

STATISTICAL TENSORS IN THE HELICITY NONTRANSVERSAL FRAME.

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Inclusive J/psi production in pp collisions at sqrt(s) = 2.76 TeV

The ALICE collaboration Abelev, B. ; Adam, J. ; Adamova, D. ; et al.

Phys.Lett.B 718 (2012) 295-306, 2012.

Inspire Record 1094079 DOI 10.17182/hepdata.62231

The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L^e_int=1.1 nb^-1 and L^mu_int=19.9 nb^-1, and the corresponding signal statistics are N_J/psi^e+e-=59 +/- 14 and N_J/psi^mu+mu-=1364 +/- 53. We present dsigma_J/psi/dy for the two rapidity regions under study and, for the forward-y range, d^2sigma_J/psi/dydp_t in the transverse momentum domain 0<p_t<8 GeV/c. The results are compared with previously published results at sqrt(s)=7 TeV and with theoretical calculations.

4 data tables

Table 1

Double differential J/$\psi$ production cross section at $\sqrt{s}=2.76$ TeV. The first uncertainty is statistical, the second one is $p_{\rm T}$-coorelated, the third one is uncorrelated. Polarization-related uncertainties are not included.

Table 2

The $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).

Table 3

the $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).

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Centrality dependence of the nuclear modification factor of charged pions, kaons, and protons in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.

Phys.Rev.C 93 (2016) 034913, 2016.

Inspire Record 1377750 DOI 10.17182/hepdata.71310

Transverse momentum ($p_{\rm{T}}$) spectra of pions, kaons, and protons up to $p_{\rm{T}} = 20$ GeV/$c$ have been measured in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV using the ALICE detector for six different centrality classes covering 0-80%. The proton-to-pion and the kaon-to-pion ratios both show a distinct peak at $p_{\rm{T}} \approx 3$ GeV/$c$ in central Pb-Pb collisions that decreases towards more peripheral collisions. For $p_{\rm{T}} > 10$ GeV/$c$, the nuclear modification factor is found to be the same for all three particle species in each centrality interval within systematic uncertainties of 10-20%. This suggests there is no direct interplay between the energy loss in the medium and the particle species composition in the hard core of the quenched jet. For $p_{\rm{T}} < 10$ GeV/$c$, the data provide important constraints for models aimed at describing the transition from soft to hard physics.

16 data tables

Table 1

Invariant yields of identified pions in Pb-Pb collisions.

Table 2

Invariant yields of identified kaons in Pb-Pb collisions.

Table 3

Invariant yields of identified protons in Pb-Pb collisions.

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Recent results on the polarization parameter in $\pi-p$ and $p-p$ elastic scattering from 6 to 12 GeV/c.

Borghini, M. ; Coignet, G. ; Dick, Louis ; et al.

(1967) 123-124, 1967.

Inspire Record 1371768 DOI 10.17182/hepdata.71256

We present the final results of a measurement of the polarization parameter P 0 in high-energy n~-p and p-p elastic scattering, performed using a target which contained polarized protons. Data were taken at beam momenta of 6.0, 8.0, 10.0 and 12.0 GeV/c for n-, and of 6.0, 10.0 and 12.0 GeV/c for n+ and p, in the interval of invariant four-momentum transfer squared-t from 0.1 to 0.75 (GeV/c)2.

11 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.