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.
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.
The cross section for photon production in association with at least one jet containing a $b$-quark hadron has been measured in proton antiproton collisions at $\sqrt{s}=1.96$ TeV. The analysis uses a data sample corresponding to an integrated luminosity of 340 pb$^{-1}$ collected with the CDF II detector. Both the differential cross section as a function of photon transverse energy $E_T^{\gamma}$, $d \sigma$($p \overline{p} \to \gamma + \geq 1 b$-jet)/$d E_T^{\gamma}$ and the total cross section $\sigma$($p \overline{p} \to \gamma + \geq 1 b$-jet/ $E_T^{\gamma}> 20$ GeV) are measured. Comparisons to a next-to-leading order prediction of the process are presented.
b + photon cross section as a function of photon ET.
b + photon total cross section for photon ET > 20 GeV.
We have measured the differential cross section for the inclusive production of psi(2S) mesons decaying to mu^{+} mu^{-1} that were produced in prompt or B-decay processes from ppbar collisions at 1.96 TeV. These measurements have been made using a data set from an integrated luminosity of 1.1 fb^{-1} collected by the CDF II detector at Fermilab. For events with transverse momentum p_{T} (psi(2S)) > 2 GeV/c and rapidity |y(psi(2S))| < 0.6 we measure the integrated inclusive cross section sigma(ppbar -> psi(2S)X) Br(psi(2S) -> mu^{+} mu^{-}) to be 3.29 +- 0.04(stat.) +- 0.32(syst.) nb.
The differential cross section times the dimuon branching fraction as a function of pT.
The integrated inclusive differential cross section for PSI(3685).
This letter reports a measurement of the cross section of prompt isolated photon pair production in p\bar p collisions at a total energy \sqrt{s} = 1.96 TeV using data of 5.36/fb integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. The measured cross section, differential in basic kinematic variables, is compared with three perturbative QCD predictions, a Leading Order (LO) parton shower calculation and two Next-to-Leading Order (NLO) calculations. The NLO calculations reproduce most aspects of the data. By including photon radiation from quarks before and after hard scattering, the parton shower prediction becomes competitive with the NLO predictions.
This article reports a measurement of the production cross section of prompt isolated photon pairs in proton-antiproton collisions at \sqrt{s} = 1.96 TeV using the CDF II detector at the Fermilab Tevatron collider. The data correspond to an integrated luminosity of 5.36/fb. The cross section is presented as a function of kinematic variables sensitive to the reaction mechanisms. The results are compared with three perturbative QCD calculations: (1) a leading order parton shower Monte Carlo, (2) a fixed next-to-leading order calculation and (3) a next-to-leading order/next-to-next-to-leading-log resummed calculation. The comparisons show that, within their known limitations, all calculations predict the main features of the data, but no calculation adequately describes all aspects of the data.
Diphoton production cross section as a function of the diphoton invariant mass.
Diphoton production cross section as a function of the diphoton transverse momentum.
Diphoton production cross section as a function of the azimuthal angle difference in the two photons.
The transverse momentum cross section of $e^+e^-$ pairs in the $Z$-boson mass region of 66-116 GeV/$c^2$ is precisely measured using Run II data corresponding to 2.1 fb$^{-1}$ of integrated luminosity recorded by the Collider Detector at Fermilab. The cross section is compared with quantum chromodynamic calculations. One is a fixed-order perturbative calculation at ${\cal O}(\alpha_s^2)$, and the other combines perturbative predictions at high transverse momentum with the gluon resummation formalism at low transverse momentum. Comparisons of the measurement with calculations show reasonable agreement. The measurement is of sufficient precision to allow refinements in the understanding of the transverse momentum distribution.
Total integrated cross section.
The differential PT cross section as a function of PT.
We present a measurement of the $\ttbar$ differential cross section with respect to the $\ttbar$ invariant mass, dSigma/dMttbar, in $\ppbar$ collisions at $\sqrt{s}=1.96$ TeV using an integrated luminosity of $2.7\invfb$ collected by the CDF II experiment. The $\ttbar$ invariant mass spectrum is sensitive to a variety of exotic particles decaying into $\ttbar$ pairs. The result is consistent with the standard model expectation, as modeled by \texttt{PYTHIA} with \texttt{CTEQ5L} parton distribution functions.
The measured differential cross section. The first error is the statistical plus jet energy scale uncertainty and the DSYS is the systematic error excluding the uncertainty in the luminosity.
The integrated cross section with statistical plus jet energy scale errors.
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
The differential cross section (nb/GeV/c) for B+ mesons as a function of pT.
The The B+ production cross section.
We measure the ratio of cross section times branching fraction, $R_p \equiv \sigma_{\chi_{c2}} {\cal B}(\chi_{c2} \to J/\psi \gamma)/ \sigma_{\chi_{c1}} {\cal B}(\chi_{c1} \to J/\psi \gamma)$, in 1.1 fb$^{-1}$ of $p\bar{p}$ collisions at $\sqrt{s} =$ 1.96 TeV. This measurement covers the kinematic range $p_T(J/\psi)>4.0$ GeV/$c$, $|\eta(J/\psi)| < 1.0$, and $p_T(\gamma)>1.0$ GeV/$c$. For events due to prompt processes, we find $R_p = 0.395\pm0.016(stat.)\pm0.015(sys.)$. This result represents a significant improvement in precision over previous measurements of prompt $\chi_{c1,2}$ hadroproduction.
Ratios of cross section times branching fractions of the X_cJ states for the prompt events and B decay events Relative systematic uncertainty +-0.037% for SIG(Q=CHI/C2)/SIG(Q=CHI/C1). Relative systematic uncertainty +-0.038% for SIG(Q=B_CHI/C2)/SIG(Q=B_CHI/C1).
We report a set of measurements of inclusive invariant transverse momentum differential cross sections of lambda, cascade and omega hyperons reconstructed in the central region with pseudorapidity within 1 and transverse momentum up to 10 GeV/c Events are collected with a minimum-bias trigger in ppbar collisions at a center-of-mass energy of 1.96 TeV using the CDF II detector at the Tevatron Collider. As transverse momentum increases, the slopes of the differential cross sections are similar not only to each other but also to those of mesons, which could indicate a universality of the particle production in transverse momentum The invariant differential cross sections are also presented for different charged-particle multiplicity intervals.
The PT differential cross section for LAMBBA production in the |pseudorapidity| range < 1.
The PT differential cross section for XI- production in the |pseudorapidity| range < 1.
The PT differential cross section for OMEGA- production in the |pseudorapidity| range < 1.
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