Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userMeasurement of the $b$ Jet Cross Section in Events with a $Z$ Boson in $pbar{p}$ Collisions at $sqrt{s}$=1.96 TeV
55
0
0.0
(
0
)
Authors
CDF Collaboration
Ask ChatGPT about the research
No Arabic abstract
A measurement of the inclusive bottom jet cross section is presented for events containing a $Z$ boson in $pbar{p}$ collisions at $sqrt{s}=1.96$ TeV using the Collider Detector at Fermilab. $Z$ bosons are identified in their electron and muon decay modes, and $b$ jets with $E_T>20$ GeV and $|eta|<1.5$ are identified by reconstructing a secondary decay vertex. The measurement is based on an integrated luminosity of about 330 ${rm pb}^{-1}$. A cross section times branching ratio of $sigma (Z+b {rm jets}) times {cal B}(Z to ell^+ ell^-)= 0.93 pm 0.36$ pb is found, where ${cal B}(Zto ell^+ ell^-)$ is the branching ratio of the $Z$ boson or $gamma^*$ into a single flavor dilepton pair ($e$ or $mu$) in the mass range between 66 and 116 GeV$/c^2$. The ratio of $b$ jets to the total number of jets of any flavor in the $Z$ sample, within the same kinematic range as the $b$ jets, is $2.36 pm 0.92%$. Here, the uncertainties are the quadratic sum of statistical and systematic uncertainties. Predictions made with NLO QCD agree, within experimental and theoretical uncertainties, with these measurements.
rate research
Read More
A measurement of the $bjet$ production cross section is presented for events containing a $Z$ boson produced in $pbar{p}$ collisions at $sqrt{s}=1.96$ TeV, using data corresponding to an integrated luminosity of 2 fb$^{-1}$ collected by the CDF II detector at the Tevatron. $Z$ bosons are selected in the electron and muon decay modes. Jets are considered with transverse energy $E_T>20$ GeV and pseudorapidity $|eta|<1.5$ and are identified as $bjets$ using a secondary vertex algorithm. The ratio of the integrated $Z+bjet$ cross section to the inclusive $Z$ production cross section is measured to be $3.32 pm 0.53 {rm (stat.)} pm 0.42 {rm (syst.)}times 10^{-3}$. This ratio is also measured differentially in jet $E_T$, jet $eta$, $Z$-boson transverse momentum, number of jets, and number of $bjets$. The predictions from leading order Monte Carlo generators and next-to-leading-order QCD calculations are found to be consistent with the measurements within experimental and theoretical uncertainties.
We present a measurement of the inclusive jet cross section using the Run II cone algorithm and data collected by the D0 experiment in p pbar collisions at a center-of-mass energy sqrt(s)=1.96 TeV, corresponding to an integrated luminosity of 0.70 fb^(-1). The jet energy calibration and the method used to extract the inclusive jet cross section are described. We discuss the main uncertainties, which are dominated by the jet energy scale uncertainty. The results cover jet transverse momenta from 50 GeV to 600 GeV with jet rapidities in the range -2.4 to 2.4 and are compared to predictions using recent proton parton distribution functions. Studies of correlations between systematic uncertainties in transverse momentum and rapidity are presented.
We describe a measurement of the ratio of the cross sections times branching fractions of the $B_c^+$ meson in the decay mode $B_c^+ rightarrow J/psi mu u$ to the $B^+$ meson in the decay mode $B^+ rightarrow J/psi K^+$ in proton-antiproton collisions at center-of-mass energy $sqrt{s}=1.96$ TeV. The measurement is based on the complete CDF Run II data set, which comes from an integrated luminosity of $8.7,{rm fb}^{-1}$. The ratio of the production cross sections times branching fractions for $B_c^+$ and $B_c^+$ mesons with momentum transverse to the beam greater than $6~textrm{GeV}/c$ and rapidity magnitude smaller than 0.6 is $0.211pm 0.012~mbox{(stat)}^{+0.021}_{-0.020}~mbox{(syst)}$. Using the known $B^+ rightarrow J/psi K^+$ branching fraction, the known $B^+$ production cross section, and a selection of the predicted $B_c^+ rightarrow J/psi mu u$ branching fractions, the range for the total $B_c^+$ production cross section is estimated.
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.
Differential cross sections for the production of $Z$ bosons or off-shell photons $gamma^*$ in association with jets are measured in proton-antiproton collisions at center-of-mass energy $sqrt{s}=1.96$ TeV using the full data set collected with the Collider Detector at Fermilab in Tevatron Run II, and corresponding to 9.6 fb$^{-1}$ of integrated luminosity. Results include first measurements at CDF of differential cross sections in events with a $Z/gamma^*$ boson and three or more jets, the inclusive cross section for production of $Z/gamma^*$ and four or more jets, and cross sections as functions of various angular observables in lower jet-multiplicity final states. Measured cross sections are compared to several theoretical predictions.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
