Related papers: Parity-violating 3-jet observables for massive qua…
I discuss the calculation of QCD jet rates in e+e- annihilation as a testing ground for parton shower simulations and jet finding algorithms.
The influence of nonvanishing quark masses on the total cross section in electron positron collisions and on the $Z$ decay rate is calculated. The corrections are expanded in $m^2/s$ and $\as$. Methods similar to those applied for the…
We discuss non-perturbative QCD contributions to jet observables, computing their dependence on the jet radius R, and on the colour and transverse momentum of the parton initiating the jet. We show, using analytic QCD models of power…
We present the calculation of the decay width of the Z-boson into three jets including complete quark mass effects to second order in the strong coupling constant. The study is done for different jet clustering algorithms such as EM, JADE,…
Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted to lead to charge separation of quarks along the orbital…
We suggest a universal QCD-motivated expression for the Polyakov-KNO multiplicity distributions of hadrons in jets and compare it with data from $e^+e^-$ annihilation experiments. The moments and overall shape of the distributions in full…
We report on the calculation of NNLO corrections to the 3-jet cross section and related event shape distributions in electron-positron annihilation. The corrections are sizable for all variables, however the magnitude of the corrections is…
We calculate the supersymmetric QCD corrections in order $\alpha_s$ to the cross section $e^+ e^- \to \sq_i \bar\sq_j$ $(i,j = 1, 2)$ within the Minimal Supersymmetric Standard Model. We pay particular attention to the case of the…
We investigate the quantum chromodynamics (QCD) corrections to hadronic final states in electron-positron collisions at $\mathcal{O}(\alpha_s^3)$ in the strong coupling constant $\alpha_s$. Namely, we analytically compute the total cross…
We discuss cross sections for hadron + hadron to 2 jets + anything in which three jet variables are measured. Such cross sections are useful especially for determining parton distributions. We define a new cross section d sigma/dX_A dX_B d…
The evolution equation for parton multiplicities in quark and gluon jets which takes into account the soft gluon interference is solved numerically using the initial conditions at threshold. If the k_T-cutoff Q_c is lowered towards the…
We study power corrections to the event shapes in $\e^+\e^--$annihilation in the two jets kinematical region, $e\ll 1$. We argue that for $e \sim \Lambda_{QCD}/Q$ all power corrections of the form $1/\lr{Qe}^n$ have to be taken into account…
Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy ion collisions. These domains are predicted to lead to charge separation of quarks along the system's…
Heavy quark jet quenching in nuclear collisions at LHC is predicted and compared using the classical gravity AdS/CFT correspondence and Standard Model perturbative QCD. The momentum independence and inverse quark mass dependence of the drag…
We report on a recent calculation of the electroweak O(\alpha^3\alpha_s) corrections to 3-jet production and related event-shape observables at e+e- colliders. The calculation properly accounts for the experimental photon isolation criteria…
We describe a measurement of the strong coupling alpha_S(m_Z) from the 3-jet rate in hadronic final states of e+e- annihilation recorded with the JADE detector at centre-of-mass energies of 14 to 44 GeV. The jets are reconstructed with the…
We present a measurement of the strong coupling alpha_S using data collected with the JADE detector at centre-of-mass energies between 14 and 44 GeV. The three-jet rate as a function of the transition parameter ycut is determined using the…
We study electron-positron annihilations into six jets at the parton level in perturbative Quantum Chromo-Dynamics (QCD), via the elementary processes $e^+e^-\ar q\bar q gggg$, $e^+e^-\ar q\bar q q'\bar q' gg$ and $e^+e^-\ar q\bar q q'\bar…
We present the first determination of the strong coupling constant from the three-jet rate in e+e- annihilation at LEP, based on a next-to-next-to-leading order (NNLO) perturbative QCD prediction. More precisely, we extract alpha_s by…
Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created in relativistic heavy ions collisions. These domains are predicted to lead to charge separation along the system orbital momentum of…