$\Sigma(c$)++ and $\Sigma(c$)0 Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Kinoshita, K. ; Pipkin, F.M. ; et al.
Phys.Rev.Lett. 62 (1989) 1240, 1989.
Inspire Record 25467 DOI 10.17182/hepdata.47269

We have observed Σc++ and Σc0 baryons in nonresonant e+e− interactions through their decays to Λc+π± using the CLEO detector. The mass difference M(Σc++)-M(Λc+) is measured to be 167.8±0.4±0.3 MeV; for M(Σc0)-M(Λc+) we find 167.9±0.5±0.3 MeV. Σc decay accounts for (18±3±5)% of Λc+ production.

2 data tables

The cross section ratio is multiplied by a factor of 1.5 to account for theunobserved SIGMA/C(2455)+.

No description provided.


Version 2
$\pi^0$ and $\eta$ meson production in proton-proton collisions at $\sqrt{s}=8$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Eur.Phys.J.C 78 (2018) 263, 2018.
Inspire Record 1620477 DOI 10.17182/hepdata.79044

An invariant differential cross section measurement of inclusive $\pi^{0}$ and $\eta$ meson production at mid-rapidity in pp collisions at $\sqrt{s}=8$ TeV was carried out by the ALICE experiment at the LHC. The spectra of $\pi^{0}$ and $\eta$ mesons were measured in transverse momentum ranges of $0.3<p_{\rm T}<35$ GeV/$c$ and $0.5<p_{\rm T}<35$ GeV/$c$, respectively. Next-to-leading order perturbative QCD calculations using fragmentation functions DSS14 for the $\pi^{0}$ and AESSS for the $\eta$ overestimate the cross sections of both neutral mesons, although such calculations agree with the measured $\eta/\pi^{0}$ ratio within uncertainties. The results were also compared with PYTHIA~8.2 predictions for which the Monash~2013 tune yields the best agreement with the measured neutral meson spectra. The measurements confirm a universal behavior of the $\eta/\pi^{0}$ ratio seen for NA27, PHENIX and ALICE data for pp collisions from $\sqrt{s}=27.5$ GeV to $\sqrt{s}=8$ TeV within experimental uncertainties. A relation between the $\pi^{0}$ and $\eta$ production cross sections for pp collisions at $\sqrt{s}=8$ TeV is given by $m_{\rm T}$ scaling for $p_{\rm T}>3.5$ GeV/$c$. However, a deviation from this empirical scaling rule is observed for transverse momenta below $p_{\rm T}<3.5$ GeV/$c$ in the $\eta/\pi^0$ ratio with a significance of $6.2\sigma$.

16 data tables

Invariant differential cross section of $\pi^0$ produced in inelastic pp collisions at center-of-mass energy 8 TeV, the uncertainty of $\sigma_{MB}$ of 2.6% is not included in the systematic error.

Invariant differential cross section of $\pi^0$ produced in inelastic pp collisions at center of mass energy 8 TeV, the uncertainty of $\sigma_{MB}$ of 2.6% is not included in the systematic error.

Invariant differential cross section of $\eta$ produced in inelastic pp collisions at center-of-mass energy 8 TeV, the uncertainty of $\sigma_{MB}$ of 2.6% is not included in the systematic error.

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${\rm f}_{0}(980)$ production in inelastic pp collisions at $\sqrt{s} = 5.02$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Phys.Lett.B 846 (2023) 137644, 2023.
Inspire Record 2094796 DOI 10.17182/hepdata.136307

The measurement of the production of ${\rm f}_{0}(980)$ in inelastic pp collisions at $\sqrt{s} = 5.02$ TeV is presented. This is the first reported measurement of inclusive ${\rm f}_{0}(980)$ yield at LHC energies. The production is measured at midrapidity, $|y| < 0.5$, in a wide transverse momentum range, $0 < p_{\rm T} < 16$ GeV/$c$, by reconstructing the resonance in the ${\rm f}_{0}(980) \rightarrow \pi^{+}\pi^{-}$ hadronic decay channel using the ALICE detector. The $p_{\rm T}$-differential yields are compared to those of pions, protons and $\phi$ mesons as well as to predictions from the HERWIG 7.2 QCD-inspired Monte Carlo event generator and calculations from a coalescence model that uses the AMPT model as an input. The ratio of the $p_{\rm T}$-integrated yield of ${\rm f}_{0}(980)$ relative to pions is compared to measurements in ${\rm e}^{+}{\rm e}^{-}$ and pp collisions at lower energies and predictions from statistical hadronisation models and HERWIG 7.2. A mild collision energy dependence of the ${\rm f}_{0}(980)$ to pion production is observed in pp collisions from SPS to LHC energies. All considered models underpredict the $p_{\rm T}$-integrated $2{\rm f}_{0}(980)/(\pi^{+}+\pi^{-})$ ratio. The prediction from the canonical statistical hadronisation model assuming a zero total strangeness content of ${\rm f}_{0}(980)$ is consistent with the data within 1.9$\sigma$ and is the closest to the data. The results provide an essential reference for future measurements of the particle yield and nuclear modification in p$-$Pb and Pb$-$Pb collisions, which have been proposed to be instrumental to probe the elusive nature and quark composition of the ${\rm f}_{0}(980)$ scalar meson.

4 data tables

$p_{\rm T}$-differential yields of $f_{0}(980)$ at midrapidity in the inelastic pp collisions at $\sqrt(s)$ = 5.02 TeV. The uncertainty 'syst' indicates the total systematic uncertainty and 'stat' indicates the statistical uncertainty. The branching ratio correction amounts to BR = (46 $\pm$ 6)% [ Phys. Rev. Lett. 111 no. 6, (2013) 062001] assuming dominance of $\pi\pi$ and KK channel has been applied to the $p_{\rm T}$-differential yields of $f_{0}(980)$. The normalisation and branching ratio relative uncertainties on the yields are independent of $p_{\rm{T}}$ and amount to 2.5% and 13%, respectively and therefore not included in the $p_{\rm T}$-differential yields of $f_{0}(980)$.

$p_{\rm T}$-integrated yield of $f_{0}(980)$, dN/dy at midrapidity as a function of $\langle {\rm d}N_{\rm ch}/{\rm d}\eta \rangle$. The uncertainty 'syst' indicates the total systematic uncertainty on the measurement. The branching ratio correction amounts to BR = (46 $\pm$ 6)% [ Phys. Rev. Lett. 111 no. 6, (2013) 062001] assuming dominance of $\pi\pi$ and KK channel has been applied to the $p_{\rm T}$-differential yields of $f_{0}(980)$. Here, the branching ratio relative uncertainty (13%) for $f_{0}(980)$ is not included.

mean-$p_{\rm{T}}$ of $f_{0}(980)$, (<$p_{\rm{T}}$>) at midrapidity as a function of $\langle {\rm d}N_{\rm ch}/{\rm d}\eta \rangle$. The uncertainty 'syst' indicates the total systematic uncertainty on the measurement.

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A MEASUREMENT OF THE PROTON STRUCTURE FUNCTIONS USING INELASTIC ELECTRON SCATTERING

Mestayer, M.D. ;
PhD Thesis, 1978.
Inspire Record 131529 DOI 10.17182/hepdata.14
54 data tables

No description provided.

No description provided.

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A Measurement of the K+ K- / pi+ pi- ratio from anti-p annihilation in deuterium and hydrogen gas

Adamo, A. ; Agnello, M. ; Balestra, F. ; et al.
Phys.Lett.B 284 (1992) 448-452, 1992.
Inspire Record 339776 DOI 10.17182/hepdata.29172

We have measured the K + K - /π + π - ratio R from p annihilations in gaseous D 2 and H 2 at atmospheric pressure. The measurement was performed with the OBELIX spectrometer. From the measured value in gaseous D 2 (0.27±0.02) we infer a P wave contribution to p −p annihilation in D 2 of (18±7)%.

1 data table

Two different triggers were used.


A Measurement of the proton-antiproton total cross-section at s**(1/2) = 1.8-TeV

The E811 collaboration Avila, C. ; Baker, W.F. ; DeSalvo, R. ; et al.
Phys.Lett.B 445 (1999) 419-422, 1999.
Inspire Record 478392 DOI 10.17182/hepdata.28126

We report a measurement of the p p ̄ total cross section at s =1.8 TeV at the Fermilab Tevatron Collider, using the luminosity independent method. Our result is σ T =71.71±2.02 mb. We also obtained values of the total elastic and total inelastic cross sections.

2 data tables

No description provided.

No description provided.


A Measurement of the psi-prime to J / psi production ratio in 920-GeV proton-nucleus interactions

The HERA-B collaboration Abt, I. ; Adams, M. ; Agari, M. ; et al.
Eur.Phys.J.C 49 (2007) 545-558, 2007.
Inspire Record 722216 DOI 10.17182/hepdata.57451

Ratios of the Psi' over the J/psi production cross sections in the dilepton channel for C, Ti and W targets have been measured in 920 GeV proton-nucleus interactions with the HERA-B detector at the HERA storage ring. The Psi' and J/psi states were reconstructed in both the mu+mu- and the e+e- decay modes. The measurements covered the kinematic range -0.35 < x_F < 0.1 with transverse momentum p_T < 4.5 GeV/c. The Psi' to J/psi production ratio is almost constant in the covered x_F range and shows a slow increase with p_T. The angular dependence of the ratio has been used to measure the difference of the Psi' and J/psi polarization. All results for the muon and electron decay channels are in good agreement: their ratio, averaged over all events, is R_psi'(mu)/R_psi'(e)=1.00+-0.08+-0.04. This result constitutes a new, direct experimental constraint on the double ratio of branching fractions, (B'(mu)*B(e))/(B(mu)*B'(e)), of Psi' and J/psi in the two channels.

3 data tables

Ratio of PSI(3685) and J/PSI cross sections for both muon and electron channels combined, obtained for different cos theta in the s-channel helicity frame.

Ratio of PSI(3685) and J/PSI cross sections for both muon and electron channels combined, obtained for intervals inpT using the data from all targets.

Ratio of PSI(3685) and J/PSI production cross sections per nucleus.


A Measurement of the tau leptonic branching fractions

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett.B 357 (1995) 715-724, 1995.
Inspire Record 398321 DOI 10.17182/hepdata.48138

A sample of 25000 Z 0 → τ + τ − events collected by the DELPHI experiment at LEP in 1991 and 1992 is used to measure the leptonic branching fractions of the τ lepton. The results are B(τ → eν ν ) = (17.51 ± 0.39) % and B(τ → μν ν ) = (17.02 ± 0.31) %. The ratio of the muon and electron couplings to the weak charged current is measured to be g μ g e = 1.000 ± 0.013 , satisfying e-μ universality. The leptonic branching fraction corrected to the value for a massless lepton, assuming e-μ universality, is found to be B(τ → lν ν ) = (17.50 ± 0.25) %.

3 data tables

Axis error includes +- 0.23/0.23 contribution (Data statistics).

Axis error includes +- 0.19/0.19 contribution (Data statistics).

Combined from the two branching fractions above. E-MU universality assumed.


A Next-to-leading order QCD analysis of neutrino - iron structure functions at the Tevatron

Seligman, William Glenn ; Shaevitz, Michael ;
FERMILAB-THESIS-1997-21, 1997.
Inspire Record 441652 DOI 10.17182/hepdata.37291

Nucleon structure functions measured in neutrino-iron and antineutrinoiron charged-current interactions are presented. The data were taken in two high-energy high-statistics runs by the LAB-E detector at the Fermilab Tevatron. Structure functions are extracted from a sample of 950,000 neutrino and 170,000 antineutrino events with neutrino energies from 30 to 360 Ge V. The structure functions $F_2$ and $xF_3$ are compared with the the predictions of perturbative Quantum Chromodynamics (PQCD). The combined non-singlet and singlet evolution in the context of PQCD gives NL0(4) . 2 value of $\Lambda^{NLO,(4)}_{\overline MS}$ = 337 ± 28 (exp.) MeV, which corresponds to $\alpha_s$ ($M^2_z$) = 0.119 ± 0.002 (exp.) ± 0.004 (theory), and with a gluon distribution given by $xG(x,Q^2_0 = 5 GeV^2$ ) = (2.22±0.34) x ($1-x)^{4.65 \pm 0.68}$

3 data tables

The cross sections are normalized to the world average of SIG(NUMU)/E/A = 0.677E-38 cm^2/GeV as no absolute flux measurement was made in this experiment.

These cross sections are normalized to the world average of SIG(NUMU)/E/A =0.677E-38 cm^2/GeV multiplied by the world average of SIG(NUMUBAR)/SIG(NUMU) i n c l u d i n g this experiment.

No description provided.


A Study of cascade and strange baryon production in sulphur - sulphur interactions at 200-GeV/c per nucleon

The OMEGA-IONS collaboration Abatzis, S. ; Andersen, E. ; Andrighetto, A. ; et al.
Phys.Lett.B 354 (1995) 178-182, 1995.
Inspire Record 395028 DOI 10.17182/hepdata.47883

Strange and multistrange baryon and antibaryon production has been studied in sulphur sulphur interactions at 200 GeV/ c per nucleon at central rapidity using the CERN Omega Spectrometer. Particle production ratios and transverse mass spectra are presented for Λ, Ξ − , Λ and Ξ − .

8 data tables

No description provided.

No description provided.

No description provided.

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