The Underlying event in hard interactions at the Tevatron anti-p p collider

The CDF collaboration Acosta, D. ; Affolder, T. ; Albrow, M.G. ; et al.
Phys.Rev.D 70 (2004) 072002, 2004.
Inspire Record 647490 DOI 10.17182/hepdata.22135

For comparison of inclusive jet cross sections measured at hadron-hadron colliders to next-to-leading order (NLO) parton-level calculations, the energy deposited in the jet cone by spectator parton interactions must first be subtracted. The assumption made at the Tevatron is that the spectator parton interaction energy is similar to the ambient level measured in minimum bias events. In this paper, we test this assumption by measuring the ambient charged track momentum in events containing large transverse energy jets at $\sqrt{s}=1800$ GeV and $\sqrt{s}=630$ GeV and comparing this ambient momentum with that observed both in minimum bias events and with that predicted by two Monte Carlo models. Two cones in $\eta$--$\phi$ space are defined, at the same pseudo-rapidity, $\eta$, as the jet with the highest transverse energy ($E_T^{(1)}$), and at $\pm 90^o$ in the azimuthal direction, $\phi$. The total charged track momentum inside each of the two cones is measured. The minimum momentum in the two cones is almost independent of $E_T^{(1)}$ and is similar to the momentum observed in minimum bias events, whereas the maximum momentum increases roughly linearly with the jet $E_T^{(1)}$ over most of the measured range. This study will help improve the precision of comparisons of jet cross section data and NLO perturbative QCD predictions. %this is new The distribution of the sum of the track momenta in the two cones is also examined for five different $E_T^{(1)}$ bins. The HERWIG and PYTHIA Monte Carlos are reasonably successful in describing the data, but neither can describe completely all of the event properties.

11 data tables

Average PT inside the max and min cone for cm energy 1800 GeV.

Data points read from plot.

Data points read from plot.

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K0(s) and Lambda0 production studies in p anti-p collisions at s**(1/2) = 1800 and 630-GeV

The CDF collaboration Acosta, D. ; Affolder, T. ; Albrow, M.G. ; et al.
Phys.Rev.D 72 (2005) 052001, 2005.
Inspire Record 681320 DOI 10.17182/hepdata.42774

We present a study of the production of K_s^0 and Lambda^0 in inelastic pbar-p collisions at sqrt(s)= 1800 and 630 GeV using data collected by the CDF experiment at the Fermilab Tevatron. Analyses of K_s^0 and Lambda^0 multiplicity and transverse momentum distributions, as well as of the dependencies of the average number and <p_T> of K_s^0 and Lambda^0 on charged particle multiplicity are reported. Systematic comparisons are performed for the full sample of inelastic collisions, and for the low and high momentum transfer subsamples, at the two energies. The p_T distributions extend above 8 GeV/c, showing a <p_T> higher than previous measurements. The dependence of the mean K_s^0(Lambda^0) p_T on the charged particle multiplicity for the three samples shows a behavior analogous to that of charged primary tracks.

36 data tables

K0S inclusive invariant PT distribution for HARD events at a centre of massenergy 1800 GeV.

K0S inclusive invariant PT distribution for MB events at a centre of mass energy 1800 GeV.

K0S inclusive invariant PT distribution for SOFT events at a centre of massenergy 1800 GeV.

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Direct photon cross section with conversions at CDF

The CDF collaboration Acosta, D. ; Affolder, T. ; Albrow, M.G. ; et al.
Phys.Rev.D 70 (2004) 074008, 2004.
Inspire Record 648506 DOI 10.17182/hepdata.42869

We present a measurement of the isolated direct photon cross section in p-pbar collisions at sqrt(s) = 1.8 TeV and |eta| &lt; 0.9 using data collected between 1994 and 1995 by the Collider Detector at Fermilab (CDF). The measurement is based on events where the photon converts into an electron-positron pair in the material of the inner detector, resulting in a two-track event signature. To remove pi0 -> gamma gamma and eta -> gamma gamma events we use a new background subtraction technique which takes advantage of the tracking information available in a photon conversion event. We find that the shape of the cross section as a function of pT is poorly described by next-to-leading-order QCD predictions, but agrees with previous CDF measurements.

1 data table

Axis error includes +- 28/18 contribution (Correlated systematic error included in quadrature in the systematic errors.).


Polarization of J / psi and psi(2S) mesons produced in p anti-p collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Abulencia, A. ; Adelman, Jahred A. ; Affolder, T. ; et al.
Phys.Rev.Lett. 99 (2007) 132001, 2007.
Inspire Record 747876 DOI 10.17182/hepdata.42742

We have measured the polarizations of J/ψ and ψ(2S) mesons as functions of their transverse momentum pT when they are produced promptly in the rapidity range |y|<0.6 with pT≥5  GeV/c. The analysis is performed using a data sample with an integrated luminosity of about 800  pb−1 collected by the CDF II detector. For both vector mesons, we find that the polarizations become increasingly longitudinal as pT increases from 5 to 30  GeV/c. These results are compared to the predictions of nonrelativistic quantum chromodynamics and other contemporary models. The effective polarizations of J/ψ and ψ(2S) mesons from B-hadron decays are also reported.

2 data tables

Polarization parameter ALPHA for J/PSI production.

Polarization parameter ALPHA for PSI(2S) production.


Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV using missing E(t) + jets events with secondary vertex b-tagging.

The CDF collaboration Abulencia, A. ; Acosta, D. ; Adelman, J. ; et al.
Phys.Rev.Lett. 96 (2006) 202002, 2006.
Inspire Record 712913 DOI 10.17182/hepdata.42775

We present a measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96 TeV which uses events with an inclusive signature of significant missing transverse energy and jets. This is the first measurement which makes no explicit lepton identification requirements, so that sensitivity to W --> tau nu decays is maintained. Heavy flavor jets from top quark decay are identified with a secondary vertex tagging algorithm. From 311 pb-1 of data collected by the Collider Detector at Fermilab we measure a production cross section of 5.8 +/- 1.2(stat.)+0.9_-0.7(syst.) pb for a top quark mass of 178 GeV/c2, in agreement with previous determinations and standard model predictions.

1 data table

TTBAR production cross section.


Measurement of the inclusive jet cross section in p anti-p interactions at s**(1/2) = 1.96-TeV using a cone-based jet algorithm

The CDF collaboration Abulencia, A. ; Acosta, D. ; Adelman, J. ; et al.
Phys.Rev.D 74 (2006) 071103, 2006.
Inspire Record 699933 DOI 10.17182/hepdata.41844

We present a measurement of the inclusive jet cross section in ppbar interactions at sqrt{s}=1.96 TeV using 385 pb^{-1} of data collected with the CDF II detector at the Fermilab Tevatron. The results are obtained using an improved cone-based jet algorithm (Midpoint). The data cover the jet transverse momentum range from 61 to 620 GeV/c, extending the reach by almost 150 GeV/c compared with previous measurements at the Tevatron. The results are in good agreement with next-to-leading order perturbative QCD predictions using the CTEQ6.1M parton distribution functions.

2 data tables

The inclusive jet cross section corrected to the hadron level.

The inclusive jet cross section corrected to the parton level.


Measurement of the inclusive jet cross section using the k(T) algorithm in p anti-p collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Abulencia, A. ; Acosta, D. ; Adelman, J. ; et al.
Phys.Rev.Lett. 96 (2006) 122001, 2006.
Inspire Record 701218 DOI 10.17182/hepdata.42758

We report on a measurement of the inclusive jet production cross section in pp-bar collisions at sqrt{s} = 1.96 TeV using data collected with the upgraded Collider Detector at Fermilab in Run II (CDF II) corresponding to an integrated luminosity of 385 pb^-1. Jets are reconstructed using the kt algorithm. The measurement is carried out for jets with rapidity 0.1 &lt; | yjet | &lt; 0.7 and transverse momentum in the range 54 &lt; ptjet &lt; 700 GeV/c. The measured cross section is in good agreement with next-to-leading order perturbative QCD predictions after the necessary non-perturbative parton-to-hadron corrections are included.

1 data table

Measured jet differential cross section as a function of PT.


A Measurement of the differential dijet mass cross-section in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.D 61 (2000) 091101, 2000.
Inspire Record 511377 DOI 10.17182/hepdata.42047

We present a measurement of the cross section for production of two or more jets as a function of dijet mass, based on an integrated luminosity of 86 pb^-1 collected with the Collider Detector at Fermilab. Our dijet mass spectrum is described within errors by next-to-leading order QCD predictions using CTEQ4HJ parton distributions, and is in good agreement with a similar measurement from the D0 experiment.

1 data table

The differential cross section for two or more jets as a function of the dijet mass.


Measurement of the t anti-t Production Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Abulencia, A. ; Acosta, D. ; Adelman, J. ; et al.
Phys.Rev.Lett. 97 (2006) 082004, 2006.
Inspire Record 718721 DOI 10.17182/hepdata.42762

We present a measurement of the top quark pair production cross section in ppbar collisions at sqrt(s)=1.96 TeV using 318 pb^{-1} of data collected with the Collider Detector at Fermilab. We select ttbar decays into the final states e nu + jets and mu nu + jets, in which at least one b quark from the t-quark decays is identified using a secondary vertex-finding algorithm. Assuming a top quark mass of 178 GeV/c^2, we measure a cross section of 8.7 +-0.9 (stat) +1.1-0.9 (syst) pb. We also report the first observation of ttbar with significance greater than 5 sigma in the subsample in which both b quarks are identified, corresponding to a cross section of 10.1 +1.6-1.4(stat)+2.0-1.3 (syst) pb.

2 data tables

Measured cross section where at least one B quark from the TOP quark decays is identified.

Measured cross section where both B quarks from the TOP quark decays are identified.


Measurement of the B+ production cross section in p anti-p collisions at s**(1/2) = 1960-GeV.

The CDF collaboration Abulencia, A. ; Adelman, Jahred A. ; Affolder, T. ; et al.
Phys.Rev.D 75 (2007) 012010, 2007.
Inspire Record 733991 DOI 10.17182/hepdata.63814

We present a new measurement of the $B^+$ meson differential cross section $d\sigma/d p_T$ at $\sqrt{s}=1960$ GeV. The data correspond to an integrated luminosity of 739pb$^{-1}$ collected with the upgraded CDF detector (CDF II) at the Fermilab Tevatron collider. $B^+$ candidates are reconstructed through the decay $B^+ \to J/\psi K^+$, with $J/\psi \to \mu^+ \mu^-$. The integrated cross section for producing $B^+$ mesons with $p_T \geq 6$ GeV/c and $|y| \leq 1$ is measured to be $2.78 \pm 0.24 \mu$b

2 data tables

The differential cross section (nb/GeV/c) for B+ mesons as a function of pT.

The The B+ production cross section.