Improving constraints on gluon spin-momentum correlations in transversely polarized protons via midrapidity open-heavy-flavor electrons in $p^{\uparrow}+p$ collisions at $\sqrt{s}=200$ GeV

The PHENIX collaboration Abdulameer, N.J. ; Acharya, U. ; Aidala, C. ; et al.
Phys.Rev.D 107 (2023) 052012, 2023.
Inspire Record 2072832 DOI 10.17182/hepdata.130883

Polarized proton-proton collisions provide leading-order access to gluons, presenting an opportunity to constrain gluon spin-momentum correlations within transversely polarized protons and enhance our understanding of the three-dimensional structure of the proton. Midrapidity open-heavy-flavor production at $\sqrt{s}=200$ GeV is dominated by gluon-gluon fusion, providing heightened sensitivity to gluon dynamics relative to other production channels. Transverse single-spin asymmetries of positrons and electrons from heavy-flavor hadron decays are measured at midrapidity using the PHENIX detector at the Relativistic Heavy Ion Collider. These charge-separated measurements are sensitive to gluon correlators that can in principle be related to gluon orbital angular momentum via model calculations. Explicit constraints on gluon correlators are extracted for two separate models, one of which had not been constrained previously.

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Data from Figure 1 of open heavy flavor $e^{\pm}$ transverse single-spin asymmetries in transversely polarized p+p collisions as a function of $p_{T}$.


Version 2
Production of D*+- mesons with dijets in deep-inelastic scattering at HERA.

The H1 collaboration Aktas, A. ; Andreev, V. ; Anthonis, T. ; et al.
Eur.Phys.J.C 51 (2007) 271-287, 2007.
Inspire Record 736052 DOI 10.17182/hepdata.45686

Inclusive D* production is measured in deep-inelastic ep scattering at HERA with the H1 detector. In addition, the production of dijets in events with a D* meson is investigated. The analysis covers values of photon virtuality 2< Q^2 <=100 GeV^2 and of inelasticity 0.05<= y <= 0.7. Differential cross sections are measured as a function of Q^2 and x and of various D* meson and jet observables. Within the experimental and theoretical uncertainties all measured cross sections are found to be adequately described by next-to-leading order (NLO) QCD calculations, based on the photon-gluon fusion process and DGLAP evolution, without the need for an additional resolved component of the photon beyond what is included at NLO. A reasonable description of the data is also achieved by a prediction based on the CCFM evolution of partons involving the k_T-unintegrated gluon distribution of the proton.

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Differential cross section for D*+- production with dijets as a function of M(C=JET2).

Differential cross section for D*+- production with dijets as a function of M(C=JET2).


Version 2
Forward jet and particle production at HERA

The H1 collaboration Adloff, C. ; Anderson, M. ; Andreev, V. ; et al.
Nucl.Phys.B 538 (1999) 3-22, 1999.
Inspire Record 476801 DOI 10.17182/hepdata.44172

Single particles and jets in deeply inelastic scattering at low x are measured with the H1 detector in the region away from the current jet and towards the proton remnant, known as the forward region. Hadronic final state measurements in this region are expected to be particularly sensitive to QCD evolution effects. Jet cross-sections are presented as a function of Bjorken-x for forward jets produced with a polar angle to the proton direction, theta, in the range 7 < theta < 20 degrees. Azimuthal correlations are studied between the forward jet and the scattered lepton. Charged and neutral single particle production in the forward region are measured as a function of Bjorken-x, in the range 5 < theta < 25 degrees, for particle transverse momenta larger than 1 GeV. QCD based Monte Carlo predictions and analytical calculations based on BFKL, CCFM and DGLAP evolution are compared to the data. Predictions based on the DGLAP approach fail to describe the data, except for those which allow for a resolved photon contribution.

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Forward Jet cross section. Axis error includes +- 7/7 contribution (Dependence of the model used to correct the data).

Forward Di-jet cross section. Axis error includes +- 7/7 contribution (Dependence of the model used to correct the data).

Data from Figure 3a on charged particle production

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Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au+Au collisions at $\sqrt{s_{NN}} = 19.6$ and 200 GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Lett.B 750 (2015) 64-71, 2015.
Inspire Record 1340691 DOI 10.17182/hepdata.72236

The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity $|y_{ee}|<1$ in minimum-bias Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened $\rho$ spectral function for $M_{ee}<1.1$ GeV/$c^{2}$. The integrated dielectron excess yield at $\sqrt{s_{NN}}$ = 19.6 GeV for $0.4<M_{ee}<0.75$ GeV/$c^2$, normalized to the charged particle multiplicity at mid-rapidity, has a value similar to that in In+In collisions at $\sqrt{s_{NN}}$ = 17.3 GeV. For $\sqrt{s_{NN}}$ = 200 GeV, the normalized excess yield in central collisions is higher than that at $\sqrt{s_{NN}}$ = 17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV is longer than those in peripheral collisions and at lower energies.

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Reconstructed dielectron unlike-sign pairs, like-sign pairs and signal distributions, together with the signal to background ratio (S/B). All columns are presented as a function of dielectron invariant mass in Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV.

Dielectron invariant mass spectrum in the STAR acceptance (|$y_{ee}$| < 1, 0.2 < $p_T^e$ < 3 GeV/c, |$\eta^e$ | < 1) after efficiency correction in Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV.

Hadronic cocktail consisting of the decays of light hadrons and correlated decays of charm in Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 GeV.

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Jet Production in ep Collisions at Low Q^2 and Determination of alpha_s

The H1 collaboration Aaron, F.D. ; Aldaya Martin, M. ; Alexa, C. ; et al.
Eur.Phys.J.C 67 (2010) 1-24, 2010.
Inspire Record 838435 DOI 10.17182/hepdata.31170

The production of jets is studied in deep-inelastic e+p scattering at low negative four momentum transfer squared 5<Q^2<100 GeV^2 and at inelasticity 0.2<y<0.7 using data recorded by the H1 detector at HERA in the years 1999 and 2000, corresponding to an integrated luminosity of 43.5 pb^-1. Inclusive jet, 2-jet and 3-jet cross sections as well as the ratio of 3-jet to 2-jet cross sections are measured as a function of Q^2 and jet transverse momentum. The 2-jet cross section is also measured as a function of the proton momentum fraction xi. The measurements are well described by perturbative quantum chromodynamics at next-to-leading order corrected for hadronisation effects and are subsequently used to extract the strong coupling alpha_s.

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Jet Production in ep Collisions at High Q^2 and Determination of alpha_s

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Alimujiang, K. ; et al.
Eur.Phys.J.C 65 (2010) 363-383, 2010.
Inspire Record 818707 DOI 10.17182/hepdata.70833

The production of jets is studied in deep-inelastic ep scattering at large negative four momentum transfer squared 150&lt;Q^2&lt;15000 GeV^2 using HERA data taken in 1999-2007, corresponding to an integrated luminosity of 395 pb^-1. Inclusive jet, 2-jet and 3-jet cross sections, normalised to the neutral current deep-inelastic scattering cross sections, are measured as functions of Q^2, jet transverse momentum and proton momentum fraction. The measurements are well described by perturbative QCD calculations at next-to-leading order corrected for hadronisation effects. The strong coupling as determined from these measurements is alpha_s(M_Z) = 0.1168 +/-0.0007 (exp.) +0.0046/-0.0030 (th.) +/-0.0016(pdf).

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Measurement of beauty and charm production in deep inelastic scattering at HERA and measurement of the beauty-quark mass

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
JHEP 09 (2014) 127, 2014.
Inspire Record 1298276 DOI 10.17182/hepdata.64204

The production of beauty and charm quarks in ep interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared 5 < Q^2 < 1000 GeV^2 using an integrated luminosity of 354 pb^{-1}. The beauty and charm content in events with at least one jet have been extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. Differential cross sections as a function of Q^2, Bjorken x, jet transverse energy and pseudorapidity were measured and compared with next-to-leading-order QCD calculations. The beauty and charm contributions to the proton structure functions were extracted from the double-differential cross section as a function of x and Q^2. The running beauty-quark mass, m_b at the scale m_b, was determined from a QCD fit at next-to-leading order to HERA data for the first time and found to be 4.07 \pm 0.14 (fit} ^{+0.01}_{-0.07} (mod.) ^{+0.05}_{-0.00} (param.) ^{+0.08}_{-0.05} (theo) GeV.

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The structure function F2(BOTTOM BOTTOMBAR) and the reduced beauty cross sections SIGR(BOTTOM BOTTOMBAR), both as functions of XB and Q**2. The measurements are given together with their statistical, systematic and extrapolation uncertainties.


Elastic and Proton-Dissociative Photoproduction of J/psi Mesons at HERA

The H1 collaboration Alexa, C. ; Andreev, V. ; Baghdasaryan, A. ; et al.
Eur.Phys.J.C 73 (2013) 2466, 2013.
Inspire Record 1228913 DOI 10.17182/hepdata.66507

Cross sections for elastic and proton-dissociative photoproduction of J/psi mesons are measured with the H1 detector in positron-proton collisions at HERA. The data were collected at $ep$ centre-of-mass energies sqrt{s} approx 318 GeV and sqrt{s} approx 225 GeV, corresponding to integrated luminosities of L = 130 pb^{-1} and L = 10.8 pb^{-1}, respectively. The cross sections are measured as a function of the photon-proton centre-of-mass energy in the range 25< Wgp < 110 GeV. Differential cross sections $\mathrm{d}\sigma / \mathrm{d}t$, where $t$ is the squared four-momentum transfer at the proton vertex, are measured in the range $|t| < 1.2 \, \gevsq$ for the elastic process and $|t| < 8 \, \gevsq$ for proton dissociation. The results are compared to other measurements. The $\Wgp$ and $t$-dependences are parametrised using phenomenological fits.

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Inclusive Deep Inelastic Scattering at High Q2 with Longitudinally Polarised Lepton Beams at HERA

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Andreev, V. ; et al.
JHEP 09 (2012) 061, 2012.
Inspire Record 1120512 DOI 10.17182/hepdata.64899

Inclusive e\pmp single and double differential cross sections for neutral and charged current deep inelastic scattering processes are measured with the H1 detector at HERA. The data were taken at a centre-of-mass energy of \surds = 319GeV with a total integrated luminosity of 333.7 pb-1 shared between two lepton beam charges and two longitudinal lepton polarisation modes. The differential cross sections are measured in the range of negative fourmomentum transfer squared, Q2, between 60 and 50 000GeV2, and Bjorken x between 0.0008 and 0.65. The measurements are combined with earlier published unpolarised H1 data to improve statistical precision and used to determine the structure function xF_3^gammaZ. A measurement of the neutral current parity violating structure function F_2^gammaZ is presented for the first time. The polarisation dependence of the charged current total cross section is also measured. The new measurements are well described by a next-to-leading order QCD fit based on all published H1 inclusive cross section data which are used to extract the parton distribution functions of the proton.

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The Charged Current Double Differential Cross Section for E+ P interactions with a beam polarisation of -37.0 % for Q^2 values of 5000, 8000, 15000, and GeV^2.


Deep inelastic cross-section measurements at large y with the ZEUS detector at HERA

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Phys.Rev.D 90 (2014) 072002, 2014.
Inspire Record 1292476 DOI 10.17182/hepdata.64778

The reduced cross sections for $e^{+}p$ deep inelastic scattering have been measured with the ZEUS detector at HERA at three different centre-of-mass energies, $318$, $251$ and $225$ GeV. The cross sections, measured double differentially in Bjorken $x$ and the virtuality, $Q^2$, were obtained in the region $0.13\ \leq\ y\ \leq\ 0.75$, where $y$ denotes the inelasticity and $5\ \leq\ Q^2\ \leq\ 110$ GeV$^2$. The proton structure functions $F_2$ and $F_L$ were extracted from the measured cross sections.

1 data table match query

The reduced cross section for the reaction E+ P --> E+ X at a centre-of-mass energy 251 GeV and Q^2=7 GeV^2 for the central-vertex region. The (sys) error shown in the table is the total systematic uncertainty, excluding the normalisation uncertainties shown separately below.