Multiple Parton Interaction Studies At Do

Download or read book Multiple Parton Interaction Studies at DØ written by and published by . This book was released on 2016 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, we present the results of studies of multiparton interactions done by the DØ collaboration using the Fermilab Tevatron at a center of mass energy of 1.96 TeV. We also present three analyses, involving three distinct final signatures: (a) a photon with at least 3 jets ([gamma] + 3jets), (b) a photon with a bottom or charm quark tagged jet and at least 2 other jets ([gamma] + b/c + 2jets), and (c) two J/ [psi] mesons. The fraction of photon + jet events initiated by double parton scattering is about 20%, while the fraction for events in which two J/ [psi] mesons were produced is 30 ± 10. While the two measurements are statistically compatible, the difference might indicate differences in the quark and gluon distribution within a nucleon. Finally, this speculation originates from the fact that photon + jet events are created by collisions with quarks in the initial states, while J/ [psi] events are produced preferentially by a gluonic initial state.