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Elastic pp scattering in the region of the coulomb interference at momenta 1.1 - 1.7 GeV/c

Vorob'ev, A.A. ; Denisov, A.S. ; Zalite, Yu.K. ; et al.

JETP Lett. 17 (1973) 108-110, 1973.

Inspire Record 1393129 DOI 10.17182/hepdata.39943

None

1 data table

Table 1

REAL/IMAG FOR FORWARD AMPLITUDE DEDUCED FROM D(SIG)/DEKIN(P=3) IN THE COULOMB-NUCLEAR INTERFERENCE REGION.

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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Mechanism of the close-to-threshold production of the eta meson.

Czyzykiewicz, R. ; Moskal, P. ; Adam, H.-H. ; et al.

Phys.Rev.Lett. 98 (2007) 122003, 2007.

Inspire Record 731185 DOI 10.17182/hepdata.41775

Measurements of the analysing power for the p(pol)p --> ppeta reaction have been performed in the close-to-threshold energy region at beam momenta of p_{beam}=2.010 and 2.085 GeV/c, corresponding to excess energies of Q=10 and 36 MeV, respectively. The determined analysing power is essentially consistent with zero implying that the eta meson is produced predominantly in the s-wave at both excess energies. The angular dependence of the analysing power, combined with the hitherto determined isospin dependence of the total cross section for the eta meson production in nucleon-nucleon collisions, reveal a statistically significant indication that the excitation of the nucleon to the S_{11}(1535) resonance, the process which intermediates the production of the eta meson, is predominantly due to the exchange of the pi meson between the colliding nucleons.

2 data tables

Table 1

Analysing power measurements for excess energy 10 MeV.

Table 2

Analysing power measurements for excess energy 36 MeV.

Threshold hyperon production in proton proton collisions at COSY-11.

Rozek, T. ; Grzonka, D. ; Adam, H.-H. ; et al.

Phys.Lett.B 643 (2006) 251-256, 2006.

Inspire Record 722758 DOI 10.17182/hepdata.31512

Sigma+ hyperon production was measured at the COSY-11 spectrometer via the p p --> n K+ Sigma+ reaction at excess energies of Q = 13 MeV and Q = 60 MeV. These measurements continue systematic hyperon production studies via the p p --> p K+ Lambda/Sigma0 reactions where a strong decrease of the cross section ratio close-to-threshold was observed. In order to verify models developed for the description of the Lambda and Sigma0 production we have performed the measurement on the Sigma+ hyperon and found unexpectedly that the total cross section is by more than one order of magnitude larger than predicted by all anticipated models. After the reconstruction of the kaon and neutron four momenta, the Sigma+ is identified via the missing mass technique. Details of the method and the measurement will be given and discussed in view of theoretical models.

1 data table

Table 1

Cross section for the reaction P P --> N K+ SIGMA+ at excess energies of 13 and 60 MeV.

Kaon pair production close to threshold.

Winter, P. ; Wolke, M. ; Adam, H.-H. ; et al.

Phys.Lett.B 635 (2006) 23-29, 2006.

Inspire Record 710616 DOI 10.17182/hepdata.41803

The total cross section of the reaction pp->ppK+K- has been measured at excess energies Q=10 MeV and 28 MeV with the magnetic spectrometer COSY-11. The new data show a significant enhancement of the total cross section compared to pure phase space expectations or calculations within a one boson exchange model. In addition, we present invariant mass spectra of two particle subsystems. While the K+K- system is rather constant for different invariant masses, there is an enhancement in the pK- system towards lower masses which could at least be partially connected to the influence of the Lambda(1405) resonance.

1 data table

Table 1

Total cross sections.

Energy dependence of the Lambda/Sigma0 production cross section ratio in p p interactions.

Kowina, P. ; Wolke, M. ; Adam, H.H. ; et al.

Eur.Phys.J.A 22 (2004) 293-299, 2004.

Inspire Record 644074 DOI 10.17182/hepdata.31762

The production of the Lambda and Sigma0 hyperons has been measured via the pp->pK+Lambda / Sigma0 reaction at the internal COSY-11 facility in the excess energy range between 14 and 60 MeV. The transition of the Lambda/Sigma0 cross section ratio from about 28 at Q<=13 MeV to the high energy level of about 2.5 is covered by the data showing a strong decrease of the ratio between 10 and 20 MeV excess energy. Effects from the final state interactions in the p-Sigma0 channel seem to be much smaller compared to the p-Lambda one. Estimates of the effective range parameters are given for the N-Lambda and the N-Sigma systems.

3 data tables

Table 1

Cross section for LAMBDA production.. Statistical errors only.

Table 2

Cross section for SIGMA0 production.. Statistical errors only.

Table 3

Energy dependence of the LAMBDA/SIGMA0 ratio.

Total and differential cross sections for the p p --> p p eta' reaction near threshold.

Khoukaz, A. ; Geck, I. ; Quentmeier, C. ; et al.

Eur.Phys.J.A 20 (2004) 345-350, 2004.

Inspire Record 642580 DOI 10.17182/hepdata.43699

The eta-prime meson production in the reaction pp-->pp eta-prime has been studied at excess energies of Q = 26.5, 32.5 and 46.6 MeV using the internal beam facility COSY-11 at the cooler synchrotron COSY. The total cross sections as well as one angular distribution for the highest Q-value are presented. The excitation function of the near threshold data can be described by a pure s-wave phase space distribution with the inclusion of the proton-proton final state interaction and Coulomb effects. The obtained angular distribution of the eta-prime mesons is also consistent with pure s-wave production.

2 data tables

Table 1

Total cross section for the reaction P P --> P P ETAPRIME.

Table 2

Angular distribution of the ETAPRIME in the CM system at an excess energy of 46.6 MeV. There is an additional systematic error of +24%/-35%.

Analysing power A(y) in the reaction p(pol.) p --> p p eta close to threshold.

Winter, P. ; Adam, H.H. ; Bauer, F. ; et al.

Phys.Lett.B 544 (2002) 251-258, 2002.

Inspire Record 599591 DOI 10.17182/hepdata.31686

Measurements of the eta meson production with a polarised proton beam in the reaction p(pol) p --> p p eta have been carried out at an excess energy of Q = 40 MeV. The dependence of the analysing power A_y on the polar angle theta^*_q of the eta meson in the center of mass system (CMS) has been studied. The data indicate the possibility of an influence of p- and d-waves to the close to threshold eta production.

1 data table

Table 1

Averaged value of the analyzing power and cross section as a function of the emmission angle of the ETA meson is the CM system.