This paper describes a measurement of the W boson transverse momentum distribution using ATLAS pp collision data from the 2010 run of the LHC at sqrt(s) = 7 TeV, corresponding to an integrated luminosity of about 31 pb^-1. Events from both W -> e nu and W -> mu nu are used, and the transverse momentum of the W candidates is measured through the energy deposition in the calorimeter from the recoil of the W. The resulting distributions are unfolded to obtain the normalized differential cross sections as a function of the W boson transverse momentum. We present results for pTW < 300 GeV in the electron and muon channels as well as for their combination, and compare the combined results to the predictions of perturbative QCD and a selection of event generators.
The normalized, differential cross secton measured in the W to Electron decay channel for the three different PT definitions, Born, Dressed and Bare.
The normalized, differential cross secton measured in the W to Muon decay channel for the three different PT definitions, Born, Dressed and Bare.
The normalized, differential cross secton from the Muon and Electron decay channel Combined for the Born-level PT definition.
Inclusive production of $\mathrm{D^{*\pm}}$ mesons in two-photon collisions was measured by the L3 experiment at LEP. The data were collected at a centre-of-mass energy $\sqrt{s} = 189$ GeV with an integrated luminosity of $176.4 \mathrm{pb^{-1}}$. Differential cross sections of the process $\mathrm{e^+e^- \to D^{*\pm} X}$ are determined as functions of the transverse momentum and pseudorapidity of the $\mathrm{D^{*\pm}}$ mesons in the kinematic region 1 GeV $< p_{T}^{\mathrm{D^*}} < 5 $ GeV and $\mathrm{|\eta^{D^*}|} < 1.4$. The cross section integrated over this phase space domain is measured to be $132 \pm 22(stat.) \pm 26(syst.)$ pb. The differential cross sections are compared with next-to-leading order perturbative QCD calculations.
The measured cross sections, as a function of PT over the bin ranges and the differential cross sections after bin-centre corrections.
The measured cross sections, as a function of pseudorapidity over the bin ranges and the differential cross sections after bin-centre corrections.
Integrated cross section in the visible kinematic region.
We report on measurements of differential cross sections d sigma/d p_t for prompt charm meson production in p anti-p collisions at s**(1/2) = 1.96 TeV using 5.8 +/- 0.3 pb-1 of data from the CDF II detector at the Fermilab Tevatron. The data are collected with a new trigger that is sensitive to the long lifetime of hadrons containing heavy flavor. The charm meson cross sections are measured in the central rapidity region |y| \leq 1 in four fully reconstructed decay modes: D0 --> K- pi+, D*+ -> D0 pi+, D+ --> K- pi+ pi+, D+_s--> phi pi+, and their charge conjugates. The measured cross sections are compared to theoretical calculations.
Measured prompt charm production cross sections for ABS(YRAP) < 1. The branching ratios used are (D0:3.81 +- 0.09 PCT), (D+:2.57 +- 0.06 PCT),(D+:9.1 +- 0.6 PCT) and (D/S+:1.8 +- 0.5 PCT).
We present a new measurement of the inclusive and differential production cross sections of $J/\psi$ mesons and $b$-hadrons in proton-antiproton collisions at $\sqrt{s}=1960$ GeV. The data correspond to an integrated luminosity of 39.7 pb$^{-1}$ collected by the CDF Run II detector. We find the integrated cross section for inclusive $J/\psi$ production for all transverse momenta from 0 to 20 GeV/$c$ in the rapidity range $|y|<0.6$ to be $4.08 \pm 0.02 (stat)^{+0.36}_{-0.33} (syst) \mu {\rm b}$. We separate the fraction of $J/\psi$ events from the decay of the long-lived $b$-hadrons using the lifetime distribution in all events with $p_T(J/\psi) > 1.25$ GeV/$c$. We find the total cross section for $b$-hadrons, including both hadrons and anti-hadrons, decaying to $J/\psi$ with transverse momenta greater than 1.25 GeV/$c$ in the rapidity range $|y(J/\psi)|<0.6$, is $ 0.330 \pm 0.005 (stat) ^{+0.036}_{-0.033} (syst) ~\mu{\rm b}$. Using a Monte Carlo simulation of the decay kinematics of $b$-hadrons to all final states containing a $J/\psi$, we extract the first measurement of the total single $b$-hadron cross section down to zero transverse momentum at $\sqrt{s}=1960$ GeV. We find the total single $b$-hadron cross section integrated over all transverse momenta for $b$-hadrons in the rapidity range $|y|<0.6$ to be $ 17.6 \pm 0.4 (stat)^{+2.5}_{-2.3} (syst) \mu{\rm b}$.
Integrated J/PSI cross section shown both uncorrected and corrected for branching ratio (5.88+-0.10PCT) of J/PSI into mu+mu-. Systematic error includes pT-dependent and fully correlated errors added in quadrature.
Differential cross section times branching ratio (5.88+-0.10PCT) into mu+mu- as a function of transverse momentum for the rapidity range -0.6 to 0.6 at a centre-of-mass energy of 1960 GeV.
Integrated bottom-hadron prouction cross section shown both uncorrected andcorrected for branching ratio (5.88+-0.10PCT) of J/PSI into mu+mu-. Systematic error includes pT-dependent and fully correlated errors added in quadrature.
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.
Measurements of the differential production cross sections in transverse momentum and rapidity for B0 mesons produced in pp collisions at sqrt(s) = 7 TeV are presented. The dataset used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 inverse picobarns. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J/Psi K-short, with the subsequent decays J/Psi to mu^+ mu^- and K-short to pi^+ pi^-. The total cross section for pt(B0) > 5 GeV and y(B0) < 2.2 is measured to be 33.2 +/- 2.5 +/- 3.5 microbarns, where the first uncertainty is statistical and the second is systematic.
Total integrated cross section in the given kinematic range. The (sys) error includes all the systematic uncertainties.
Measured differential cross section as a function of the transverse momentum of the B0 particle.
Measured differential cross section as a function of the rapidity of the B0 particle.
Measurements of the total and differential cross sections with respect to transverse momentum and rapidity for B+ mesons produced in pp collisions at sqrt(s) = 7 TeV are presented. The data correspond to an integrated luminosity of 5.8 inverse picobarns collected by the CMS experiment operating at the LHC. The exclusive decay B+ to J/psi K+, with the J/psi decaying to an oppositely charged muon pair, is used to detect B+ mesons and to measure the production cross section as a function of the transverse momentum and rapidity of the B. The total cross section for p_t(B) > 5 GeV and |y(B)| < 2.4 is measured to be 28.1 +/- 2.4 +/- 2.0 +/- 3.1 microbarns, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.
Total integrated cross section in the given kinematic range. The (sys) error includes the uncertainty in the branching fraction.
Measured differential cross section as a function of the transverse momentum of the B+ particle.
Measured differential cross section as a function of the rapidity of the B+ particle.
The B^0_s differential production cross section is measured as functions of the transverse momentum and rapidity in pp collisions at sqrt(s) = 7 TeV, using the J/Psi phi decay, and compared with predictions based on perturbative QCD calculations at next-to-leading order. The data sample, collected by the CMS experiment at the LHC, corresponds to an integrated luminosity of 40 inverse picobarns. The B^0_s is reconstructed from the decays J/Psi to an oppositely charged muon pair and phi to K+ K-. The integrated B^0_s cross section times B^0_s to J/Psi phi branching fraction in the range 8 < pt(B) < 50 GeV/c and |y(b)| < 2.4 is measured to be 6.9 +/- 0.6 +/- 0.6 nb, where the first uncertainty is statistical and the second is systematic.
Total integrated B/S cross section times the branching fraction to J/PSI PHI in the given kinematic range.
The measured differential cross section as a function of the transverse momentum of the B/S in the |rapidity| range < 24.
The measured differential cross section as a function of the rapidity of the B/S in the transverse momentum range 8 to 50 GeV.
This letter presents measurements of the differential cross-sections for inclusive electron and muon production in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using data collected by the ATLAS detector at the LHC. The muon cross-section is measured as a function of pT in the range 4 < pT < 100 GeV and within pseudorapidity |eta| < 2.5. In addition the electron and muon cross-sections are measured in the range 7 < pT < 26 GeV and within |eta| <2.0, excluding 1.37<|eta|<1.52. Integrated luminosities of 1.3 pb-1 and 1.4 pb-1 are used for the electron and muon measurements, respectively. After subtraction of the W/Z/gamma* contribution, the differential cross-sections are found to be in good agreement with theoretical predictions for heavy-flavour production obtained from Fixed Order NLO calculations with NLL high-pT resummation, and to be sensitive to the effects of NLL resummation.
Differential cross section as a function of PT for electron heavy-flavour production in the |pseudorapidity| region < 2.0 (excluding 1.37 to 1.52). The systematic error includes the 3.4% luminosity uncertainty.
Inclusive muon cross section for |eta| < 2.5 and pT > 4 GeV: (stat) statistical error, (sys) systematic error.The first systematic error is the intrinsic error of the measurement, the second the error is due to the luminosity.
Inclusive muon cross section after subtraction of W,Z, Drell-Yan and top background for |eta| < 2.5 and pT > 4 GeV: (stat) statistical error, (sys) systematic error. The first systematic error is the intrinsic error of the measurement, the second the error due to the luminosity, the third is due to the subtraction of the background and is dominated by the error on the W, Z inclusive cross sections.
The jet fragmentation function and transverse profile for jets with 25 GeV < ptJet < 500 GeV and etaJet<1.2 produced in proton-proton collisions with a center-of-mass energy of 7 TeV are presented. The measurement is performed using data with an integrated luminosity of 36 pb^-1. Jets are reconstructed and their momentum measured using calorimetric information. The momenta of the charged particle constituents are measured using the tracking system. The distributions corrected for detector effects are compared with various Monte Carlo event generators and generator tunes. Several of these choices show good agreement with the measured fragmentation function. None of these choices reproduce both the transverse profile and fragmentation function over the full kinematic range of the measurement.
Charged particle fragmentation function in the jet-Pt range 25 TO 40 GeV.
Charged particle fragmentation function in the jet-Pt range 40 TO 60 GeV.
Charged particle fragmentation function in the jet-Pt range 60 TO 80 GeV.
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