655 research outputs found

    Event Shape Analysis in ALICE

    Full text link
    The jets are the final state manifestation of the hard parton scattering. Since at LHC energies the production of hard processes in proton-proton collisions will be copious and varied, it is important to develop methods to identify them through the study of their final states. In the present work we describe a method based on the use of some shape variables to discriminate events according their topologies. A very attractive feature of this analysis is the possibility of using the tracking information of the TPC+ITS in order to identify specific events like jets. Through the correlation between the quantities: thrust and recoil, calculated in minimum bias simulations of proton-proton collisions at 10 TeV, we show the sensitivity of the method to select specific topologies and high multiplicity. The presented results were obtained both at level generator and after reconstruction. It remains that with any kind of jet reconstruction algorithm one will confronted in general with overlapping jets. The present method determines areas where one does encounter special topologies of jets in an event. The aim is not to supplant the usual jet reconstruction algorithms, but rather to allow an easy selection of events allowing then the application of algorithms.Comment: 24 pages, ALICE Not

    Effect of hard processes on momentum correlations

    Full text link
    The effect of hard processes to be encountered in HBT studies at the Large Hadron Collider have been studied. A simple simulation has allowed us to generate momentum correlations involving jet particles as well as particles originating from the kinetic freeze out and to compare them to a simple theoretical model which has been developed. The first results on the effect of hard processes on the correlation function for the case of jet quenching are presented.Comment: 9 pages, 12 figures, talk presented at 2nd Warsaw Meeting on Particle Correlations and Resonances in Heavy Ion Collision

    Color reconnection and flow-like patterns in pp collisions

    Full text link
    Increasingly, with the data collected at the LHC we are confronted with the possible existence of flow in pp collisions. In this work we show that PYTHIA 8 produces flow-like effects in events with multiple hard subcollisions due to color string formations between final partons from independent hard scatterings, the so called color reconnection. We present studies of different identified hadron observables in pp collisions at 7 TeV with the tune 4C. Studies have been done both for minimum bias and multiplicity intervals in events with and without color reconnection to isolate the flow-like effect.Comment: 4 pages, 4 figures. The first part of the manuscript was reorganized, some typos were corrected and references added. The final version should appear in PR
    corecore