Global polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons in Au+Au collisions at $\sqrt{s_{\rm NN}}=19.6$ and $27$ GeV

The STAR collaboration Abdulhamid, M.I. ; Aboona, B.E. ; Adam, J. ; et al.
Phys.Rev.C 108 (2023) 014910, 2023.
Inspire Record 2659670 DOI 10.17182/hepdata.140936

In relativistic heavy-ion collisions, a global spin polarization, $P_\mathrm{H}$, of $\Lambda$ and $\bar{\Lambda}$ hyperons along the direction of the system angular momentum was discovered and measured across a broad range of collision energies and demonstrated a trend of increasing $P_\mathrm{H}$ with decreasing $\sqrt{s_{NN}}$. A splitting between $\Lambda$ and $\bar{\Lambda}$ polarization may be possible due to their different magnetic moments in a late-stage magnetic field sustained by the quark-gluon plasma which is formed in the collision. The results presented in this study find no significant splitting at the collision energies of $\sqrt{s_{NN}}=19.6$ and $27$ GeV in the RHIC Beam Energy Scan Phase II using the STAR detector, with an upper limit of $P_{\bar{\Lambda}}-P_{\Lambda}<0.24$% and $P_{\bar{\Lambda}}-P_{\Lambda}<0.35$%, respectively, at a 95% confidence level. We derive an upper limit on the na\"ive extraction of the late-stage magnetic field of $B<9.4\cdot10^{12}$ T and $B<1.4\cdot10^{13}$ T at $\sqrt{s_{NN}}=19.6$ and $27$ GeV, respectively, although more thorough derivations are needed. Differential measurements of $P_\mathrm{H}$ were performed with respect to collision centrality, transverse momentum, and rapidity. With our current acceptance of $|y|<1$ and uncertainties, we observe no dependence on transverse momentum and rapidity in this analysis. These results challenge multiple existing model calculations following a variety of different assumptions which have each predicted a strong dependence on rapidity in this collision-energy range.

5 data tables

The first-order event-plane resolution determined by the STAR EPD as a function of collision centrality is roughly doubled in comparison to previous analyses using the STAR BBC. We see $R_{\rm EP}^{(1)}$ peak for mid-central collisions.

The mid-central $P_{\rm H}$ measurements reported in this work are shown alongside previous measurements in the upper panel, and are consistent with previous measurements at the energies studied here. The difference between integrated $P_{\bar{\Lambda}}$ and $P_{\Lambda}$ is shown at $\sqrt{s_{\rm{NN}}}$=19.6 and 27 GeV alongside previous measurements in the lower panel. The splittings observed with these high-statistics data sets are consistent with zero. Statistical uncertainties are represented as lines while systematic uncertainties are represented as boxes. The previous $P_{\bar{\Lambda}}-P_{\Lambda}$ result at $\sqrt{s_{\rm NN}}=7.7$ GeV is outside the axis range, but is consistent with zero within $2\sigma$.

$P_{\rm H}$ measurements are shown as a function of collision centrality at $\sqrt{s_{\rm NN}}$=19.6 and 27 GeV. Statistical uncertainties are represented as lines while systematic uncertainties are represented as boxes. $P_{\rm H}$ increases with collision centrality at $\sqrt{s_{\rm NN}}$=19.6 and 27 GeV, as expected from an angular-momentum-driven phenomenon.

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Energy Dependence of Intermittency for Charged Hadrons in Au+Au Collisions at RHIC

The STAR collaboration Abdulhamid, Muhammad ; Aboona, Bassam ; Adam, Jaroslav ; et al.
Phys.Lett.B 845 (2023) 138165, 2023.
Inspire Record 2626682 DOI 10.17182/hepdata.137849

Density fluctuations near the QCD critical point can be probed via an intermittency analysis in relativistic heavy-ion collisions. We report the first measurement of intermittency in Au$+$Au collisions at $\sqrt{s_\mathrm{_{NN}}}$ = 7.7-200 GeV measured by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The scaled factorial moments of identified charged hadrons are analyzed at mid-rapidity and within the transverse momentum phase space. We observe a power-law behavior of scaled factorial moments in Au$+$Au collisions and a decrease in the extracted scaling exponent ($\nu$) from peripheral to central collisions. The $\nu$ is consistent with a constant for different collisions energies in the mid-central (10-40%) collisions. Moreover, the $\nu$ in the 0-5% most central Au$+$Au collisions exhibits a non-monotonic energy dependence that reaches a possible minimum around $\sqrt{s_\mathrm{_{NN}}}$ = 27 GeV. The physics implications on the QCD phase structure are discussed.

53 data tables

The scaled factorial moments, $F_{q}(M)$($q=$ 2-6), of identified charged hadrons ($h^{\pm}$) multiplicity in the most central (0-5\%) Au$+$Au collisions at $\sqrt{s_\mathrm{_{NN}}}$ = 7.7 GeV.

The scaled factorial moments, $F_{q}(M)$($q=$ 2-6), of identified charged hadrons ($h^{\pm}$) multiplicity in the most central (0-5\%) Au$+$Au collisions at $\sqrt{s_\mathrm{_{NN}}}$ = 19.6 GeV.

The scaled factorial moments, $F_{q}(M)$($q=$ 2-6), of identified charged hadrons ($h^{\pm}$) multiplicity in the most central (0-5\%) Au$+$Au collisions at $\sqrt{s_\mathrm{_{NN}}}$ = 39 GeV.

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Beam Energy Dependence of Triton Production and Yield Ratio ($\mathrm{N}_t \times \mathrm{N}_p/\mathrm{N}_d^2$) in Au+Au Collisions at RHIC

The STAR collaboration Abdulhamid, Muhammad ; Aboona, Bassam ; Adam, Jaroslav ; et al.
Phys.Rev.Lett. 130 (2023) 202301, 2023.
Inspire Record 2152917 DOI 10.17182/hepdata.133992

We report the triton ($t$) production in mid-rapidity ($|y| <$ 0.5) Au+Au collisions at $\sqrt{s_\mathrm{NN}}$= 7.7--200 GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider (RHIC). The nuclear compound yield ratio ($\mathrm{N}_t \times \mathrm{N}_p/\mathrm{N}_d^2$), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity ($dN_{ch}/d\eta$) and follows a scaling behavior. The $dN_{ch}/d\eta$ dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3$\sigma$ and 3.4$\sigma$, respectively, giving a combined significance of 4.1$\sigma$. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller $p_{T}$ acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.

68 data tables

Invariant yields of tritons at 7.7 GeV, all centralities. The first uncertainty is statistical uncertainty, the second is systematic uncertainty.

Invariant yields of tritons at 11.5 GeV, all centralities. The first uncertainty is statistical uncertainty, the second is systematic uncertainty.

Invariant yields of tritons at 14.5 GeV, all centralities. The first uncertainty is statistical uncertainty, the second is systematic uncertainty.

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Transverse energy production and charged-particle multiplicity at midrapidity in various systems from $\sqrt{s_{NN}}=7.7$ to 200 GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 93 (2016) 024901, 2016.
Inspire Record 1394433 DOI 10.17182/hepdata.96601

Measurements of midrapidity charged particle multiplicity distributions, $dN_{\rm ch}/d\eta$, and midrapidity transverse-energy distributions, $dE_T/d\eta$, are presented for a variety of collision systems and energies. Included are distributions for Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$, 130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, Cu$+$Cu collisions at $\sqrt{s_{_{NN}}}=200$ and 62.4 GeV, Cu$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, U$+$U collisions at $\sqrt{s_{_{NN}}}=193$ GeV, $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, $^{3}$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, and $p$$+$$p$ collisions at $\sqrt{s_{_{NN}}}=200$ GeV. Centrality-dependent distributions at midrapidity are presented in terms of the number of nucleon participants, $N_{\rm part}$, and the number of constituent quark participants, $N_{q{\rm p}}$. For all $A$$+$$A$ collisions down to $\sqrt{s_{_{NN}}}=7.7$ GeV, it is observed that the midrapidity data are better described by scaling with $N_{q{\rm p}}$ than scaling with $N_{\rm part}$. Also presented are estimates of the Bjorken energy density, $\varepsilon_{\rm BJ}$, and the ratio of $dE_T/d\eta$ to $dN_{\rm ch}/d\eta$, the latter of which is seen to be constant as a function of centrality for all systems.

28 data tables

Transverse energy in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

Multiplicity in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

Transverse energy in Au+Au collisions at $\sqrt{s_{NN}}$ = 130 GeV

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Measurement of higher cumulants of net-charge multiplicity distributions in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=7.7-200$ GeV

The PHENIX collaboration Adare, A. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.C 93 (2016) 011901, 2016.
Inspire Record 1378005 DOI 10.17182/hepdata.146751

We report the measurement of cumulants ($C_n, n=1\ldots4$) of the net-charge distributions measured within pseudorapidity ($|\eta|<0.35$) in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=7.7-200$ GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider. The ratios of cumulants (e.g. $C_1/C_2$, $C_3/C_1$) of the net-charge distributions, which can be related to volume independent susceptibility ratios, are studied as a function of centrality and energy. These quantities are important to understand the quantum-chromodynamics phase diagram and possible existence of a critical end point. The measured values are very well described by expectation from negative binomial distributions. We do not observe any nonmonotonic behavior in the ratios of the cumulants as a function of collision energy. The measured values of $C_1/C_2 = \mu/\sigma^2$ and $C_3/C_1 = S\sigma^3/\mu$ can be directly compared to lattice quantum-chromodynamics calculations and thus allow extraction of both the chemical freeze-out temperature and the baryon chemical potential at each center-of-mass energy.

10 data tables

Efficiency corrected cumulants of net-charge distributions as a function of $\langle N_{part} \rangle$ from Au+Au collisions at different collision energies.

Efficiency corrected cumulants of net-charge distributions as a function of $\langle N_{part} \rangle$ from Au+Au collisions at different collision energies.

Efficiency corrected cumulants of net-charge distributions as a function of $\langle N_{part} \rangle$ from Au+Au collisions at different collision energies.

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Two-pion Bose-Einstein correlations in central PbPb collisions at sqrt(s_NN) = 2.76 TeV

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett.B 696 (2011) 328-337, 2011.
Inspire Record 881884 DOI 10.17182/hepdata.56743

The first measurement of two-pion Bose-Einstein correlations in central Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.

14 data tables

Projections of the correlation function C.

Projections of the correlation function C.

Projections of the correlation function C.

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Midrapidity antiproton-to-proton ratio in pp collisions at $\sqrt{s} = 0.9$ and $7$~TeV measured by the ALICE experiment

The ALICE collaboration Aamodt, K. ; Abel, N. ; Abeysekara, U. ; et al.
Phys.Rev.Lett. 105 (2010) 072002, 2010.
Inspire Record 859610 DOI 10.17182/hepdata.55557

The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at $\sqrt{s} = 0.9$ and $7$ TeV during the initial running periods of the Large Hadron Collider(LHC). The measurement covers the transverse momentum interval $0.45 < p_{\rm{t}} < 1.05$ GeV/$c$ and rapidity $|y| < 0.5$. The ratio is measured to be $R_{|y| < 0.5} = 0.957 \pm 0.006 (stat.) \pm 0.014 (syst.)$ at $0.9$ TeV and $R_{|y| < 0.5} = 0.991 \pm 0.005 (stat.) \pm 0.014 (syst.)$ at $7$ TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.

2 data tables

The PT dependence of the pbar/p ratio for the central rapidity region ABS(YRAP)<0.5.

The central rapidity pbar/p ratio as a function of the rapidity interval Ybeam-Ybaryon and centre-of-mass energy. As well as the present ALICE measurements this table also lists the values from other experiments (see the text of the paper for details).


Deep inelastic scattering with leading protons or large rapidity gaps at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Nucl.Phys.B 816 (2009) 1-61, 2009.
Inspire Record 804915 DOI 10.17182/hepdata.52860

The dissociation of virtual photons, $\gamma^{\star} p \to X p$, in events with a large rapidity gap between $X$ and the outgoing proton, as well as in events in which the leading proton was directly measured, has been studied with the ZEUS detector at HERA. The data cover photon virtualities $Q^2>2$ GeV$^2$ and $\gamma^{\star} p$ centre-of-mass energies $40&lt;W&lt;240$ GeV, with $M_X>2$ GeV, where $M_X$ is the mass of the hadronic final state, $X$. Leading protons were detected in the ZEUS leading proton spectrometer. The cross section is presented as a function of $t$, the squared four-momentum transfer at the proton vertex and $\Phi$, the azimuthal angle between the positron scattering plane and the proton scattering plane. It is also shown as a function of $Q^2$ and $\xpom$, the fraction of the proton's momentum carried by the diffractive exchange, as well as $\beta$, the Bjorken variable defined with respect to the diffractive exchange.

48 data tables

The differential cross section DSIG/DT for the LRG and the LPS data samples.

The fitted exponential slope of the T distribution as a function of X(NAME=POMERON).

The fitted exponential slope of the T distribution as a function of X(NAME=POMERON).

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Measurement of j / psi production in continuum e+ e- annihilations near s**(1/2) = 10.6-GeV

The BaBar collaboration Aubert, Bernard ; Boutigny, D. ; Gaillard, J.M. ; et al.
Phys.Rev.Lett. 87 (2001) 162002, 2001.
Inspire Record 558091 DOI 10.17182/hepdata.19450

The production of $J/\psi$ mesons in continuum $e^+e^-$ annihilations has been studied with the BABAR detector at energies near the $\Upsilon(4S)$ resonance, approximately 10.6 GeV. The mesons are distinguished from $J/\psi$ production in B decays through their center-of-mass momentum and energy. We measure the cross section $e^+e^-\to J/\psi X$ to be $2.52\pm 0.21\pm 0.21$ pb: for momentum above 2 GeV/c, it is $1.87\pm 0.10\pm 0.15$ pb. We set a 90% confidence level upper limit on the branching fraction for direct $\Upsilon(4S)$\to J/\psi X$ decays at $4.7\times 10^{-4}$.

1 data table

Cross section measurement.


Search for first-generation scalar and vector leptoquarks

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abdesselam, A. ; et al.
Phys.Rev.D 64 (2001) 092004, 2001.
Inspire Record 557085 DOI 10.17182/hepdata.42922

We describe a search for the pair production of first-generation scalar and vector leptoquarks in the eejj and enujj channels by the D0 Collaboration. The data are from the 1992--1996 ppbar run at sqrt{s} = 1.8 TeV at the Fermilab Tevatron collider. We find no evidence for leptoquark production; in addition, no kinematically interesting events are observed using relaxed selection criteria. The results from the eejj and enujj channels are combined with those from a previous D0 analysis of the nunujj channel to obtain 95% confidence level (C.L.) upper limits on the leptoquark pair-production cross section as a function of mass and of beta, the branching fraction to a charged lepton. These limits are compared to next-to-leading-order theory to set 95% C.L. lower limits on the mass of a first-generation scalar leptoquark of 225, 204, and 79 GeV/c^2 for beta=1, 1/2, and 0, respectively. For vector leptoquarks with gauge (Yang-Mills) couplings, 95% C.L. lower limits of 345, 337, and 206 GeV/c^2 are set on the mass for beta=1, 1/2, and 0, respectively. Mass limits for vector leptoquarks are also set for anomalous vector couplings.

3 data tables

No description provided.

No description provided.

No description provided.


Cross-section for b jet production in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 85 (2000) 5068-5073, 2000.
Inspire Record 531669 DOI 10.17182/hepdata.42975

Bottom quark production in pbar-p collisions at sqrt(s)=1.8 TeV is studied with 5 inverse picobarns of data collected in 1995 by the DO detector at the Fermilab Tevatron Collider. The differential production cross section for b jets in the central rapidity region (|y(b)| < 1) as a function of jet transverse energy is extracted from a muon-tagged jet sample. Within experimental and theoretical uncertainties, DO results are found to be higher than, but compatible with, next-to-leading-order QCD predictions.

1 data table

No description provided.


Search for second generation leptoquark pairs in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 84 (2000) 2088-2093, 2000.
Inspire Record 508772 DOI 10.17182/hepdata.42087

We have searched for second generation leptoquark (LQ) pairs in the \mu\mu+jets channel using 94+-5 pb^{-1} of pbar-p collider data collected by the D0 experiment at the Fermilab Tevatron during 1993-1996. No evidence for a signal is observed. These results are combined with those from the \mu\nu+jets and \nu\nu+jets channels to obtain 95% confidence level (C.L.) upper limits on the LQ pair production cross section as a function of mass and $beta, the branching fraction of a LQ decay into a charged lepton and a quark. Lower limits of 200(180) GeV/c^2 for \beta=1(1/2) are set at the 95% C.L. on the mass of scalar LQ. Mass limits are also set on vector leptoquarks as a function of \beta.

1 data table

No description provided.


Small angle muon and bottom quark production in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 84 (2000) 5478-5483, 2000.
Inspire Record 503949 DOI 10.17182/hepdata.42072

This Letter describes a measurement of the muon cross section originating from b quark decay in the forward rapidity range 2.4 < y(mu) < 3.2 in pbarp collisions at sqrt(s) = 1.8 TeV. The data used in this analysis were collected by the D0 experiment at the Fermilab Tevatron. We find that NLO QCD calculations underestimate b quark production by a factor of four in the forward rapidity region. A cross section measurement using muon+jet data has been included in this version of the paper.

3 data tables

The forward muon cross section (per unit rapidity).

The cross section for muons originating from b-quark decay.

Integrated cross sections for muons originating from b-quark decay. The statistical and systematic errors are added in quadrature.


The b anti-b production cross-section and angular correlations in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Lett.B 487 (2000) 264-272, 2000.
Inspire Record 499943 DOI 10.17182/hepdata.42088

We present measurements of the b-bbar production cross section and angular correlations using the D0 detector at the Fermilab Tevatron p-pbar Collider operating at sqrt(s) = 1.8 TeV. The b quark production cross section for |y(b)|<1.0 and p_T(b)>6 GeV/c is extracted from single muon and dimuon data samples. The results agree in shape with the next-to-leading order QCD calculation of heavy flavor production but are greater than the central values of these predictions. The angular correlations between b and bbar quarks, measured from the azimuthal opening angle between their decay muons, also agree in shape with the next-to-leading order QCD prediction.

3 data tables

No description provided.

The errors are combinations of statistical and systematic uncertainties.

The distribution of MU+ MU- azimuthal angle difference.


Studies of W W and W Z production and limits on anomalous W W gamma and W W Z couplings

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.D 60 (1999) 072002, 1999.
Inspire Record 499282 DOI 10.17182/hepdata.42124

Evidence of anomalous WW and WZ production was sought in pbar{p} collisions at a center-of-mass energy of sqrt(s) = 1.8 TeV. The final states $WW (WZ) to mu-nu-jet-jet + X, WZ to mu-nu-e-e + X and WZ to e-nu-e-e + X were studied using a data sample corresponding to an integrated luminosity of approximately 90 pb-1. No evidence of anomalous diboson production was found. Limits were set on anomalous WWgamma and WWZ couplings and were combined with our previous results. The combined 95% confidence level anomalous coupling limits for Lambda=2 TeV are -0.25 LE Delta-kappa LE 0.39 (lambda=0) and -0.18 LE lambda LE 0.19 (Delta \kappa = 0), assuming the WWgamma couplings are equal to the WWZ couplings.

2 data tables

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: g = g0/(1 + M(gamma Z)**2/CONST(NAME=SCALE)**2)**n. KAPPA_GZ means KAPPA_GAMMA = KAPPA_Z. LAMBDA_GZ means LAMBDA_GAMMA = LAMBDA_Z.

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: g = g0/(1 + M(gamma Z)**2/CONST(NAME=SCALE)**2)**n.


Z gamma production in anti-p p collisions S**(1/2) = 1.8-TeV and limits on anomalous Z Z gamma and Z gamma gamma couplings

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.D 57 (1998) R3817-R3821, 1998.
Inspire Record 465977 DOI 10.17182/hepdata.42169

We present a study of Z +gamma + X production in p-bar p collisions at sqrt{S}=1.8 TeV from 97 (87) pb^{-1} of data collected in the eegamma (mumugamma) decay channel with the D0 detector at Fermilab. The event yield and kinematic characteristics are consistent with the Standard Model predictions. We obtain limits on anomalous ZZgamma and Zgammagamma couplings for form factor scales Lambda = 500 GeV and Lambda = 750 GeV. Combining this analysis with our previous results yields 95% CL limits |h{Z}_{30}| < 0.36, |h{Z}_{40}| < 0.05, |h{gamma}_{30}| < 0.37, and |h{gamma}_{40}| < 0.05 for a form factor scale Lambda=750 GeV.

1 data table

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: h = hi0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n. See article for details.


The Inclusive jet cross-section in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 2451-2456, 1999.
Inspire Record 473457 DOI 10.17182/hepdata.42154

We have made a precise measurement of the central inclusive jet cross section at sqrt(s) = 1.8 TeV. The measurement is based on an integrated luminosity of 92 pb-1 collected at the Fermilab Tevatron pbar-p Collider with the D-Zero detector. The cross section, reported as a function of jet transverse energy (ET >= 60 GeV) in the pseudorapidity interval |eta| <= 0.5, is in good agreement with predictions from next-to-leading order quantum chromodynamics.

2 data tables

Inclusive cross section for ABS(ETARAP)<0.5. The quoted systematic (DSYS) errors do not include the luminosity uncertainty of 6.1 PCT.

Inclusive cross section for 0.1<=ABS(ETARAP)<=0.7. Data are taken from the AIP E-PAPS ftp site shown above. The quoted (DSYS) errors are the total systematic errors including the luminosity uncertainty.


Small angle J / psi production in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 35-40, 1999.
Inspire Record 473954 DOI 10.17182/hepdata.42141

This paper presents the first measurement of the inclusive J/Psi production cross section in the forward pseudorapidity region 2.5<|eta|<3.7 in ppbar collisions at sqrt(s)=1.8TeV. The results are based on 9.8 pb-1 of data collected using the D0 detector at the Fermilab Tevatron Collider. The inclusive J/Psi cross section for transverse momenta between 1 and 16 GeV/c is compared with theoretical models of charmonium production.

1 data table

Only statistical errors are shown. Cross section tines branching ratio.


The Dijet mass spectrum and a search for quark compositeness in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 2457-2462, 1999.
Inspire Record 473420 DOI 10.17182/hepdata.42143

Using the DZero detector at the 1.8 TeV pbarp Fermilab Tevatron collider, we have measured the inclusive dijet mass spectrum in the central pseudorapidity region |eta_jet| < 1.0 for dijet masses greater than 200 Gev/c^2. We have also measured the ratio of spectra sigma(|eta_jet| < 0.5)/sigma(0.5 < |eta_jet| < 1.0). The order alpha_s^3 QCD predictions are in good agreement with the data and we rule out models of quark compositeness with a contact interaction scale < 2.4 TeV at the 95% confidence level.

2 data tables

Dijet cross section for ABS(ETARAP)<1.0.

Ratio of cross sections for ABS(ETARAP) < 0.5 / 0.5 < ABS(ETARAP) < 1.0.


Search for first generation scalar leptoquark pairs in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 80 (1998) 2051-2056, 1998.
Inspire Record 450538 DOI 10.17182/hepdata.42159

We have searched for first generation scalar leptoquark (LQ) pairs in the enu+jets channel using ppbar collider data (integrated luminosity= 115 pb^-1) collected by the DZero experiment at the Fermilab Tevatron during 1992-96. The analysis yields no candidate events. We combine the results with those from the ee+jets and nunu+jets channels to obtain 95% confidence level (CL) upper limits on the LQ pair production cross section as a function of mass and of beta, the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c^2 for beta=1, 1/2, and 0, respectively.

1 data table

The cross section values are extracted with the assumption that BR(LQ --> EQUARK) = 1/2.


Limits on W W Z and W W gamma couplings from p anti-p ---> e neutrino jet jet X events at s**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 79 (1997) 1441-1446, 1997.
Inspire Record 443148 DOI 10.17182/hepdata.42199

We present limits on anomalous WWZ and WW-gamma couplings from a search for WW and WZ production in p-bar p collisions at sqrt(s)=1.8 TeV. We use p-bar p -> e-nu jjX events recorded with the D0 detector at the Fermilab Tevatron Collider during the 1992-1995 run. The data sample corresponds to an integrated luminosity of 96.0+-5.1 pb~(-1). Assuming identical WWZ and WW-gamma coupling parameters, the 95% CL limits on the CP-conserving couplings are -0.33<lambda<0.36 (Delta-kappa=0) and -0.43<Delta-kappa<0.59 (lambda=0), for a form factor scale Lambda = 2.0 TeV. Limits based on other assumptions are also presented.

1 data table

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: g = g0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n.


Search for anomalous W W and W Z production in p anti-p collisions at s**(1/2) = 1.8-TeV

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 77 (1996) 3303-3308, 1996.
Inspire Record 419962 DOI 10.17182/hepdata.42290

We present results from a search for anomalous WW and WZ production in ppbar collisions at sqrt(s) = 1.8 TeV. We used ppbar->evjjX events observed during the 1992-1993 run of the Fermilab Tevatron collider, corresponding to an integrated luminosity of 13.7 +- 0.7 pb^-1. A fit to the transverse momentum spectrum of the W boson yields direct limits on the CP-conserving anomalous WWgamma and WWZ coupling parameters of -0.9 &lt; delta kappa &lt; 1.1 (with lambda = 0) and -0.6 &lt; lambda &lt; 0.7 (with delta kappa = 0) at the 95% confidence level, for a form factor scale Lambda = 1.5 TeV, assuming that the WWgamma and WWZ coupling parameters are equal.

1 data table

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: g = g0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n.


Exclusive rho0 and phi muoproduction at large q**2

The New Muon collaboration Arneodo, M. ; Arvidson, A. ; Badełek, B. ; et al.
Nucl.Phys.B 429 (1994) 503-529, 1994.
Inspire Record 380946 DOI 10.17182/hepdata.48319

Exclusive ϱ 0 and φ muoproduction on deuterium, carbon and calcium has been studied in the kinematic range 2< Q 2 < 25 GeV 2 and 40 < ν < 180GeV. We discuss the Q 2 dependence of the cross sections, the transverse momentum distributions for the vector mesons, the decay angular distributions and, in the case of the ϱ 0 , nuclear effects. The data for 0 production are compatible with a diffractive mechanism. The distinct features of φ production are a smaller cross section and less steep p t 2 distributions than those for the 0 mesons.

7 data tables

No description provided.

No description provided.

No description provided.

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A Reevaluation of the Gottfried sum

The New Muon collaboration Arneodo, M. ; Arvidson, A. ; Badelek, B. ; et al.
Phys.Rev.D 50 (1994) R1-R3, 1994.
Inspire Record 358419 DOI 10.17182/hepdata.71293

We present a new determination of the nonsinglet structure function ${\mathit{F}}_{2}^{\mathit{p}}$ - ${\mathit{F}}_{2}^{\mathit{n}}$ at ${\mathit{Q}}^{2}$=4 ${\mathrm{GeV}}^{2}$ using recently measured values of ${\mathit{F}}_{2}^{\mathit{d}}$ and ${\mathit{F}}_{2}^{\mathit{n}}$/${\mathit{F}}_{2}^{\mathit{p}}$. A new evaluation of the Gottfried sum is given, which remains below the simple quark-parton model value of 1/3.

4 data tables

Errors of F2(D) are the estimated total uncertainties and those on the ratio and difference are statistical only.

Values of the Gottfried Sum Rule integral (GS) defined as the integral between X(C=MIN) and X = 0.8 of (F2(P)-F2(N))DX/X.

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Muoproduction of J / psi and the gluon distribution of the nucleon

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, G. ; et al.
Z.Phys.C 56 (1992) 21-28, 1991.
Inspire Record 336767 DOI 10.17182/hepdata.14559

Measurements are presented of the inclusive distributions of theJ/Ψ meson produced by muons of energy 200 GeV from an ammonia target. The gluon distribution of the nucleon has been derived from the data in the range 0.04<x<0.36 using a technique based on the colour singlet model. An arbitrary normalisation factor is required to obtain a reasonable integral of the gluon distribution. Some comments are made on the use ofJ/Ψ productionby virtual photons to extract the gluon distribution at HERA.

7 data tables

Data are normalized to total cross section of 36 nb (not corrected for coherence).

Data are normalized to total cross section of 36 nb (not corrected for coherence).

Data are normalized to total cross section of 36 nb (not corrected for coherence).

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