Measurements of longitudinal and transverse momentum distributions for neutral pions in the forward-rapidity region with the LHCf detector

The LHCf collaboration Adriani, O. ; Berti, E. ; Bonechi, L. ; et al.
Phys.Rev.D 94 (2016) 032007, 2016.
Inspire Record 1385877 DOI 10.17182/hepdata.74066

The differential cross sections for inclusive neutral pions as a function of transverse and longitudinal momentum in the very forward rapidity region have been measured at the Large Hadron Collider (LHC) with the Large Hadron Collider forward detector (LHCf) in proton-proton collisions at $\sqrt{s}=$ 2.76 and 7 TeV and in proton-lead collisions at nucleon-nucleon center-of-mass energies of $\sqrt{s_\text{NN}}=$ 5.02 TeV. Such differential cross sections in proton-proton collisions are compatible with the hypotheses of limiting fragmentation and Feynman scaling. Comparing proton-proton with proton-lead collisions, we find a sizable suppression of the production of neutral pions in the differential cross sections after subtraction of ultra-peripheral proton-lead collisions. This suppression corresponds to the nuclear modification factor value of about 0.1-0.3. The experimental measurements presented in this paper provide a benchmark for the hadronic interaction Monte Carlo simulation codes that are used for the simulation of cosmic ray air showers.

20 data tables

The average $\pi^{0}$ transverse momenta for the rapidity range $8.8<y<10.6$ in $p+p$ collisions at $\sqrt{s}=2.76$ and 7 TeV and for the rapidity range $-8.8>y_\rm{lab}>-10.6$ in $p+\rm{Pb}$ collisions at $\sqrt{s_\rm{NN}}=5.02$ TeV. The rapidity values for $p+\rm{Pb}$ collisions are in the detector reference frame and must be multiplied by -1.

Production rate for the $\pi^{0}$ production in the rapidity range $8.8 < y < 9.0$ in $p+p$ collisions and in the rapidity range $-8.8 > y_\rm{lab} > -9.0$ in $p+\rm{Pb}$ collisions.

Production rate for the $\pi^{0}$ production in the rapidity range $9.0 < y < 9.2$ in $p+p$ collisions and in the rapidity range $-9.0 > y_\rm{lab} > -9.2$ in $p+\rm{Pb}$ collisions.

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Inclusive cross sections, charge ratio and double-helicity asymmetries for $\pi^+$ and $\pi^-$ production in $p$$+$$p$ collisions at $\sqrt{s}$=200 GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.D 91 (2015) 032001, 2015.
Inspire Record 1315330 DOI 10.17182/hepdata.71403

We present the midrapidity charged pion invariant cross sections and the ratio of $\pi^-$-to-$\pi^+$ production ($5<p_T<13$ GeV/$c$), together with the double-helicity asymmetries ($5<p_T<12$ GeV/$c$) in polarized $p$$+$$p$ collisions at $\sqrt{s} = 200$ GeV. The cross section measurements are consistent with perturbative calculations in quantum chromodynamics within large uncertainties in the calculation due to the choice of factorization, renormalization, and fragmentation scales. However, the theoretical calculation of the ratio of $\pi^-$-to-$\pi^+$ production when considering these scale uncertainties overestimates the measured value, suggesting further investigation of the uncertainties on the charge-separated pion fragmentation functions is needed. Due to cancellations of uncertainties in the charge ratio, direct inclusion of these ratio data in future parameterizations should improve constraints on the flavor dependence of quark fragmentation functions to pions. By measuring charge-separated pion asymmetries, one can gain sensitivity to the sign of $\Delta G$ through the opposite sign of the up and down quark helicity distributions in conjunction with preferential fragmentation of positive pions from up quarks and negative pions from down quarks. The double-helicity asymmetries presented are sensitive to the gluon helicity distribution over an $x$ range of $\sim$0.03--0.16.

3 data tables

Invariant cross section for $\pi^+$ and $\pi^-$ hadrons, as well as the statistical and systematic uncertainties. In addition, there is an absolute scale uncertainty of 9.6$\%$.

Double-helicity asymmetries and statistical uncertainties for $\pi^+$ and $\pi^-$ hadrons. The primary systematic uncertainties, which are fully correlated between points, are $1.4\times10^{-3}$ from relative luminosity and a $^{+7.0\%}_{-7.7\%}$ scaling uncertainty from beam polarization.

Ratio of charged pion cross section, as shown in Fig.6.


EXPERIMENTAL DATA ON CUMULATIVE PION PRODUCTION AT 8.9-GeV/c PROTON INTERACTION WITH LIGHT NUCLEI

Baldin, A.M. ; Bondarev, V.K. ; Giordenescu, N. ; et al.
JINR-1-82-28, 1982.
Inspire Record 184670 DOI 10.17182/hepdata.71072

None

49 data tables

No description provided.

No description provided.

No description provided.

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Production of kshort, kstar(892)and phi(1020) in minimum bias events and kshort and lambda in jets in pbar p collisions at sqrt(s)=1.96 TeV

The CDF collaboration Aaltonen, T. ; Albrow, M. ; Alvarez Gonzalez, B. ; et al.
Phys.Rev.D 88 (2013) 092005, 2013.
Inspire Record 1247975 DOI 10.17182/hepdata.64398

We report measurements of the inclusive transverse momentum pT distribution of centrally produced kshort, kstar(892), and phi(1020) mesons up to pT = 10 GeV/c in minimum-bias events, and kshort and lambda particles up to pT = 20 GeV/c in jets with transverse energy between 25 GeV and 160 GeV in pbar p collisions. The data were taken with the CDF II detector at the Fermilab Tevatron at sqrt(s) = 1.96 TeV. We find that as pT increases, the pT slopes of the three mesons (kshort, kstar, and phi) are similar, and the ratio of lambda to kshort as a function of pT in minimum-bias events becomes similar to the fairly constant ratio in jets at pT ~ 5 GeV/c. This suggests that the particles with pT >~ 5 GeV/c in minimum-bias events are from soft jets, and that the pT slope of particles in jets is insensitive to light quark flavor (u, d, or s) and to the number of valence quarks. We also find that for pT <~ 4 GeV relatively more lambda baryons are produced in minimum-bias events than in jets.

5 data tables

The inclusive invariant differential cross section for K0S production.

The inclusive invariant differential cross section for PHI production.

The inclusive invariant differential cross section for K*(892)+- production.

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Cross Section and Transverse Single-Spin Asymmetry of $\eta$ Mesons in $p^{\uparrow}+p$ Collisions at $\sqrt{s}=200$ GeV at Forward Rapidity

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.D 90 (2014) 072008, 2014.
Inspire Record 1300542 DOI 10.17182/hepdata.64267

We present a measurement of the cross section and transverse single-spin asymmetry ($A_N$) for $\eta$ mesons at large pseudorapidity from $\sqrt{s}=200$~GeV $p^{\uparrow}+p$ collisions. The measured cross section for $0.5<p_T<5.0$~GeV/$c$ and $3.0<|\eta|<3.8$ is well described by a next-to-leading-order perturbative-quantum-chromodynamics calculation. The asymmetries $A_N$ have been measured as a function of Feynman-$x$ ($x_F$) from $0.2<|x_{F}|<0.7$, as well as transverse momentum ($p_T$) from $1.0<p_T<4.5$~GeV/$c$. The asymmetry averaged over positive $x_F$ is $\langle{A_{N}}\rangle=0.061{\pm}0.014$. The results are consistent with prior transverse single-spin measurements of forward $\eta$ and $\pi^{0}$ mesons at various energies in overlapping $x_F$ ranges. Comparison of different particle species can help to determine the origin of the large observed asymmetries in $p^{\uparrow}+p$ collisions.

4 data tables

The measured ETA meson cross section, E*D3(SIG)/DP**3, versus PT at forward rapidity. The statistical and systematic uncertainties are type-A and type-B uncertainties respectively.

ASYM(PEAK) and ASYM(BG) for ETA mesons measured as a function of XF in the range 0.3 < ABS(XF) < 0.7 from the 4X4B triggered dataset. The values represented are the weighted mean of the South and North MPC (Muon Piston Calorimeter). The uncertainties listed are statistical only.

ASYM for ETA mesons measured as a function of XF in the range 0.2 < ABS(XF) < 0.7. Uncertainties listed are those due to the statistics, the XF uncorrelated uncertainties due to extracting the yields, and the correlated relative luminosity uncertainty.

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Inclusive Pion Production in 360-{GeV}/$c p p$ Interactions

The EHS-RCBC collaboration Bailly, J.L. ; Bartl, W. ; Buschbeck, B. ; et al.
Z.Phys.C 35 (1987) 309, 1987.
Inspire Record 245413 DOI 10.17182/hepdata.17437

In a study of proton-proton interactions at\(\sqrt s= 26GeV\), inclusive distributions of single pions and systems of pions of various charge combinations are presented, as well as the production ratio obtained in association with various trigger particles. The results are compared to current phenomenological models in an attempt to understand multiparticle productions in hadron collisions.

1 data table

Neutral pion and $\eta$ meson production in proton-proton collisions at $\sqrt{s}=0.9$ TeV and $\sqrt{s}=7$ TeV

The ALICE collaboration Abelev, B. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett.B 717 (2012) 162-172, 2012.
Inspire Record 1116147 DOI 10.17182/hepdata.58871

The first measurements of the invariant differential cross sections of inclusive $\pi^0$ and $\eta$ meson production at mid-rapidity in proton-proton collisions at $\sqrt{s}=0.9$ TeV and $\sqrt{s}=7$ TeV are reported. The $\pi^0$ measurement covers the ranges $0.4<p_T<7$ GeV/$c$ and $0.3<p_T<25$ GeV/$c$ for these two energies, respectively. The production of $\eta$ mesons was measured at $\sqrt{s}=7$ TeV in the range $0.4<p_T<15$ GeV/$c$. Next-to-Leading Order perturbative QCD calculations, which are consistent with the $\pi^0$ spectrum at $\sqrt{s}=0.9$ TeV, overestimate those of $\pi^0$ and $\eta$ mesons at $\sqrt{s}=7$ TeV, but agree with the measured $\eta/\pi^0$ ratio at $\sqrt{s}=7$ TeV.

4 data tables

The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 7 TeV.

The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 0.9 TeV.

The measured invariant differential section for inclusive ETA production at a centre-of-mass energy of 7 TeV.

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Measurement of Bottom versus Charm as a Function of Transverse Momentum with Electron-Hadron Correlations in p+p Collisions at sqrt(s)=200 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 103 (2009) 082002, 2009.
Inspire Record 816469 DOI 10.17182/hepdata.57326

The momentum distribution of electrons from semi-leptonic decays of charm and bottom for mid-rapidity |y|<0.35 in p+p collisions at sqrt(s)=200 GeV is measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) over the transverse momentum range 2 < p_T < 7 GeV/c. The ratio of the yield of electrons from bottom to that from charm is presented. The ratio is determined using partial D/D^bar --> e^{+/-} K^{-/+} X (K unidentified) reconstruction. It is found that the yield of electrons from bottom becomes significant above 4 GeV/c in p_T. A fixed-order-plus-next-to-leading-log (FONLL) perturbative quantum chromodynamics (pQCD) calculation agrees with the data within the theoretical and experimental uncertainties. The extracted total bottom production cross section at this energy is \sigma_{b\b^bar}= 3.2 ^{+1.2}_{-1.1}(stat) ^{+1.4}_{-1.3}(syst) micro b.

6 data tables

Bottom contribution to the electrons from heavy flavor decay as a function of PT. These values has been obtained using g3data software which to extract the data from the plot and should therefore be used with caution. The g3data program indicates an extra uncertainty of 0.01 on these values.

Differential bottom production cross section at mid rapidity (y=0) To obtain this value, the differential "bottom-decay" electrons cross-section has been extrapolated to PT=0 using the spectrum shape predicted by pQCD. The b->e branching ratio used was 10 +-1%.

Invariant cross section of electrons from heavy flavor decay versus PT These values has been obtained using g3data software which to extract the data from the plot and should therefore be used with caution. The values in the last column indicate the level of uncertainty intoduced by g3data.

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Measurement of high-p(T) single electrons from heavy-flavor decays in p + p collisions at s**(1/2) = 200-GeV.

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 97 (2006) 252002, 2006.
Inspire Record 725484 DOI 10.17182/hepdata.57283

The momentum distribution of electrons from decays of heavy flavor (charm and beauty) for midrapidity |y| < 0.35 in p+p collisions at sqrt(s) = 200 GeV has been measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) over the transverse momentum range 0.3 < p_T < 9 GeV/c. Two independent methods have been used to determine the heavy flavor yields, and the results are in good agreement with each other. A fixed-order-plus-next-to-leading-log pQCD calculation agrees with the data within the theoretical and experimental uncertainties, with the data/theory ratio of 1.72 +/- 0.02^stat +/- 0.19^sys for 0.3 < p_T < 9 GeV/c. The total charm production cross section at this energy has also been deduced to be sigma_(c c^bar) = 567 +/- 57^stat +/- 224^sys micro barns.

3 data tables

Heavy-flavor decay electrons invariant differential cross-section An additional 10% normalization uncertainty is to add.

Differential charm cross section To obtain this value, the differential "charm-decay" electrons cross-section, integrated over PT>0.4 GeV/c, has been extrapolated down to PT=0 using the spectrum shape predicted by a fixed-order-plus-next-to-leading-log (FONLL)calculation. The contribution from beauty and beauty cascades, estimated to be 0.1 microbarn, has been substracted, and the c->e branching ratio used was 9.5 +- 1.0%.

Total charm cross section To obtain the total charm cross section, the differential charm cross section has been extrapolated to the whole rapidity range, using a HVQMNR rapidity distribution with aCTEQ5M PDF.


Identified charged hadron production in p+p collisions at sqrt(s)=200 and 62.4 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 83 (2011) 064903, 2011.
Inspire Record 886590 DOI 10.17182/hepdata.57021

Transverse momentum distributions and yields for $\pi^{\pm}$, $K^{\pm}$, $p$ and $\bar{p}$ in $p+p$ collisions at $\sqrt{s}$=200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC). These data provide important baseline spectra for comparisons with identified particle spectra in heavy ion collisions at RHIC. We present the inverse slope parameter $T_{\rm inv}$, mean transverse momentum $<p_T>$ and yield per unit rapidity $dN/dy$ at each energy, and compare them to other measurements at different $\sqrt{s}$ in $p+p$ and $p+\bar{p}$ collisions. We also present the scaling properties such as $m_T$ scaling, $x_T$ scaling on the $p_T$ spectra between different energies. To discuss the mechanism of the particle production in $p+p$ collisions, the measured spectra are compared to next-to-leading-order or next-to-leading-logarithmic perturbative quantum chromodynamics calculations.

8 data tables

Invariant cross sections for inclusive PI+ and PI- production in P P collisions at a centre-of-mass energy of 200 GeV. There is an additional normalization uncertainty of 9.7 PCT.

Invariant cross sections for inclusive K+ and K- production in P P collisions at a centre-of-mass energy of 200 GeV. There is an additional normalization uncertainty of 9.7 PCT.

Invariant cross sections for inclusive P and PBAR production in P P collisions at a centre-of-mass energy of 200 GeV with feed-down weak decay corrections NOT applied. There is an additional normalization uncertainty of 9.7 PCT.

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