Related papers: Planar Property and Long-range Azimuthal Correlati…
A search for partonic collective effects inside jets produced in proton-proton collisions is performed via correlation measurements of charged constituents using the CMS detector at the CERN LHC. The analysis uses data collected at a…
Methodology is presented for analysis of two-particle azimuthal angle correlation functions obtained in collisions at ultra-relativistic energies. We show that harmonic and di-jet contributions to these correlation functions can be reliably…
This article reviews the status of event-shape studies in e+e- annihilation and DIS. It includes discussions of perturbative calculations, of various approaches to modelling hadronisation and of comparisons to data.
We calculate the azimuthal anisotropy $v_2$ extracted from the large $\Delta y$ region of two particle $\Delta y-\Delta\phi$ correlations in a two-jet system, in which, the masses of the jets are not negligible compared to their energies.…
We show how a difference in the correlation length longitudinally and transversely, with respect to the jet axis in e+e- annihilation, arises naturally in a model for Bose-Einstein correlations based on the Lund string model. In genuine…
Hadronic jets are extremely abundant at the LHC, and testing QCD in various corners of phase-space is important to understand backgrounds and some specific signatures of new physics. In this article, various measurements aiming at probing…
The Modified Leading Log Approximation of QCD and the local parton hadron duality picture are shown to give a fully satisfactory description of data on charged particle energy spectra in $e^+e^-$ annihilation. The analysis of data in terms…
We briefly report our recent progress on the study of the polarized fragmentation functions of $\Lambda$ hyperon in unpolarized semi-inclusive deep-inelastic scatterings and electron-positron annihilations at low energies. In particular, we…
The novel phenomena observed in particle angular correlations are reviewed. They include the double-peak away-side azimuthal correlations in relativistic heavy-ion collisions and the long-range pseudorapidity near-side (ridge) correlations…
Azimuthal correlation functions are used to study jet- and di-jet properties as a function of centrality in Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$=200 GeV. Utilizing a novel technique to decompose the correlation function into a…
Using the formalism obtained from collinear expansion, we calculate the differential cross section and azimuthal asymmetries in semi-inclusive deeply inelastic lepton-nucleon (nucleus) scattering process $e^-+N (A) \to e^-+q+X$ with both…
The hot and dense medium produced in relativistic heavy-ion collisions has been conjectured to be accompanied by an axial charge asymmetry that may lead to a separation of electric charges in the direction of the extremely strong magnetic…
This work reports the first observation of azimuthal asymmetries around the thrust axis in $e^+e^-$ annihilation of pairs of back-to-back charged pions in one hemisphere, and $\pi^0$ and $\eta$ mesons in the opposite hemisphere. These…
We postulate that non-perturbative QCD effects occurring during parton fragmentation can result in collective effects of a multi-parton system, reminiscent of those observed in high-energy hadronic or nuclear interactions with large…
Azimuthal anisotropy is a key observation made in ultrarelativistic heavy-ion collisions. This phenomenon has played a crucial role in the development of the field over the last two decades. In addition to its interest for studying the…
Azimuthal angle two particle correlations have been shown to be a powerful probe for extracting novel features of jet induced correlations produced in Au+Au collisions at RHIC. At intermediate $p_T$, 2-5GeV/c, the jets have been shown to be…
The correlation between the longitudinal polarization of a fragmenting quark and the transverse momenta of the produced hadrons was predicted over two decades ago. Nevertheless, experimental searches in the electron-positron annihilation…
We show that the next-to-leading order perturbative prediction, matched with the next-to-leading logarithmic approximation for predicting both two-, three- and four-jet rates using the Durham jet-clustering algorithm, in the 0.001 < ycut <…
A large variety of jet properties can be described perturbatively by evolving the parton cascade down to small scales of order of a few 100 MeV. We discuss two recent applications of this approach: 1. the soft limit of the particle spectrum…
We derive the probability for rapidity gaps in a parton cascade and investigate the dual connection with hadronic final states. A good description of observations in e+e- annihilations is obtained by perturbative QCD calculations in MLLA…