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Energy dependence of forward-rapidity J/$\psi$ and $\psi(2S)$ production in pp collisions at the LHC

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.

Eur.Phys.J.C 77 (2017) 392, 2017.

Inspire Record 1511865 DOI 10.17182/hepdata.77781

We present results on transverse momentum ($p_{\rm T}$) and rapidity ($y$) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive J/$\psi$ and $\psi(2S)$ at forward rapidity ($2.5<y<4$) as well as $\psi(2S)$-to-J/$\psi$ cross section ratios. These quantities are measured in pp collisions at center of mass energies $\sqrt{s}=5.02$ and 13 TeV with the ALICE detector. Both charmonium states are reconstructed in the dimuon decay channel, using the muon spectrometer. A comprehensive comparison to inclusive charmonium cross sections measured at $\sqrt{s}=2.76$, 7 and 8 TeV is performed. A comparison to non-relativistic quantum chromodynamics and fixed-order next-to-leading logarithm calculations, which describe prompt and non-prompt charmonium production respectively, is also presented. A good description of the data is obtained over the full $p_{\rm T}$ range, provided that both contributions are summed. In particular, it is found that for $p_{\rm T}>15$ GeV/$c$ the non-prompt contribution reaches up to 50% of the total charmonium yield.

14 data tables

Table 1

Differential production cross sections of $J/\psi$ as a function of $p_{\rm T}$.

Table 2

Differential production cross sections of $J/\psi$ as a function of rapidity.

Table 3

Differential production cross sections of $\psi(2S)$ as a function of $p_{\rm T}$.

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Measurement of the beam asymmetry $\Sigma$ for $\pi^0$ and $\eta$ photoproduction on the proton at $E_\gamma = 9$ GeV

The GlueX collaboration Al Ghoul, H. ; Anassontzis, E.G. ; Austregesilo, A. ; et al.

Phys.Rev.C 95 (2017) 042201, 2017.

Inspire Record 1511149 DOI 10.17182/hepdata.76745

We report measurements of the photon beam asymmetry $\Sigma$ for the reactions $\vec{\gamma}p\to p\pi^0$ and $\vec{\gamma}p\to p\eta $ from the GlueX experiment using a 9 GeV linearly-polarized, tagged photon beam incident on a liquid hydrogen target in Jefferson Lab's Hall D. The asymmetries, measured as a function of the proton momentum transfer, possess greater precision than previous $\pi^0$ measurements and are the first $\eta$ measurements in this energy regime. The results are compared with theoretical predictions based on $t$-channel, quasi-particle exchange and constrain the axial-vector component of the neutral meson production mechanism in these models.

2 data tables

Table 1

Measurement of the beam asymmetry $\Sigma$ for $\pi^0$ photoproduction on the proton at $E_\gamma = 9$ GeV. The uncorrelated systematic errors (syst) are given in the table below along with a correlated normalization uncertainty (norm) of 3.6% due to the beam polarization.

Table 2

Measurement of the beam asymmetry $\Sigma$ for $\eta$ photoproduction on the proton at $E_\gamma = 9$ GeV. The uncorrelated systematic errors (syst) are given in the table below along with a correlated normalization uncertainty (norm) of 3.6% due to the beam polarization.

Elastic scattering of antiprotons on polarized protons at 1.73, 2.13, 2.37 and 2.97 GeV/c

Daum, C. ; Erné, F.C. ; Lagnaux, J.P. ; et al.

Nucl.Phys.B 6 (1968) 617-627, 1968.

Inspire Record 1392687 DOI 10.17182/hepdata.806

Differential cross section and polarization distributions are presented for elastic p p scattering at incident momenta of 1.73, 2.13, 2.37 and 2.97 GeV/ c . The data have been analysed in terms of a 5-parameter diffraction model. In terms of this model the difference in the shape of the differential cross sections for p p and pp elastic scattering is a result of the strong absorption in the p p system.

11 data tables

Table 1

'1'. '2'. '3'. '4'.

Table 2

'3'.

Table 3

'2'.

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Measurement of the triple scattering parameter $R_{pn}$ at C.M.S. angle of 70°, and phase shift analysis at 630 MeV

Kazarinov, Yu.M. ; Lehar, F. ; Pisarev, A.F. ; et al.

Sov.J.Nucl.Phys. 5 (1967) 97-100, 1967.

Inspire Record 1392562 DOI 10.17182/hepdata.17309

None

2 data tables

Table 1

DATA FOR DEUTERIUM.

Table 2

DATA FOR CARBON.

Backward π p elastic scattering at 2.85 and 3.30 GeV/c

Baker, W.F. ; Carlson, P.J. ; Chabaud, V. ; et al.

Phys.Lett.B 25 (1967) 361-364, 1967.

Inspire Record 1389663 DOI 10.17182/hepdata.29442

Backward elastic scattering has been measured for π + p at 2.85 and 3.30 GeV/ c and for π − p at 3.30 GeV/ c . The π + p angular distributions show steep backward peaks, whereas the π − p distribution is flatter. At 2.85 GeV/ c the π + p differential cross section close to 180° is more than twice that at 3.30 GeV/ c , supporting the assignment J P = 11 2 + for Δ δ (2420) resonance. The π + p data at 2.85 GeV/ c indicate the onset of a dip at cos θ c.m. ≈ −0.97.

3 data tables

Table 1

The data for cos(theta) = 1 is the extrapolation.

Table 2

The data for cos(theta) = 1 and U = 0 are the extrapolations.

Table 3

The data for cos(theta) = 1 and U = 0 are the extrapolations.

Backward Kp elastic scattering at 3.55 GeV/c

Banaigs, J. ; Berger, J. ; Bonnel, C. ; et al.

Phys.Lett.B 24 (1967) 90462 317-320, 1967.

Inspire Record 1389626 DOI 10.17182/hepdata.29619

Backward elastic K+p and K−p scattering has been measured in the angular interval 168o <θc.m. < 177o. We find <math altimg="si1.gif">(<rm>d</rm>σ/<rm>d</rm>Ω) <inf loc="post"><rm>K</rm>+<rm>p</rm> → <rm>pK</rm>+</inf> = 17 ± 4 μ<rm>b</rm>/<rm>sr</rm></math> and <math altimg="si2.gif">(<rm>d</rm>σ/<rm>d</rm>Ω)<inf loc="post"><rm>K</rm>−<rm>p</rm> → <rm>pK</rm>−</inf> < 0.6 μ<rm>b</rm>/<rm>sr</rm></math>. K+p elastic scattering exhibits a backward peak.

2 data tables

Table 1

The data for cos(theta) = 1 is the extrapolation.

Table 2

The data for cos(theta) = 1 is the extrapolation.

The angular distribution of backward elastically scattered pions at 3.55 GeV/c

Baker, W.F. ; Carlson, P.J. ; Chabaud, V. ; et al.

Phys.Lett. 23 (1966) 605-609, 1966.

Inspire Record 1389621 DOI 10.17182/hepdata.29776

The elastic scattering of 3.55 GeV/ c π + and π − mesons by protons was measured at centre-of-mass angles between 165° and 177°. The angular distributions for 864 events show a steeply rising backward peak for π + p, while the shape is less clear for π − p.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Extrapolations.

Total cross-section for n-p and n-d scattering at 10 GeV/c neutron momentum

Engler, J. ; Horn, K. ; König, J. ; et al.

Phys.Lett.B 27 (1968) 599-601, 1968.

Inspire Record 1389110 DOI 10.17182/hepdata.752

The total neutron cross-sections were measured with high precision for hydrogen and deuterium. At an average neutron momentum of 10 GeV/c we obtained σ T (np)=39.5±0.5 mb and σ T (nd)=73.3±1.1 mb. These values are in excellent agreement with p-p and p-d total cross sections. No energy dependence was found for n-p cross section between 4 and 10 GeV/c.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

Differential cross sections for backward π− p → nπ0 from 2.6 to 8 GeV/c

DeMarzo, C. ; Guerriero, L. ; Nicolini, C. ; et al.

Phys.Lett.B 56 (1975) 487-490, 1975.

Inspire Record 1389073 DOI 10.17182/hepdata.27860

We report differential cross sections for π − p → n π 0 in the backward hemisphere at incident momenta of 2.6, 3.5, 4.3, 6.0, and 8.0 GeV/c. We observe less pronounced structure than some previous measurements with a shallow dip displaced from that seen in π + p elastic scattering.

5 data tables

Table 1

'N'.

Table 2

'N'.

Table 3

'N'.