Browsing Faculty & Staff Research by Title

J/ψ and ψ (2S) production in pp collisions at √s=7Tev

CMS Collaboration; Adair, A.; Boulahouache, C.; Cuplov, V.; Ecklund, K.M.; (2012)

A measurement of the J/ψ and ψ(2S) production cross sections in pp collisions at √s=7TeV with the CMS experiment at the LHC is presented. The data sample corresponds to an integrated luminosity of 37 pb−1. Using a fit to the invariant mass and decay length distributions, production cross sections have been measured separately for prompt and non-prompt ...

J/ψ polarization in p+p collisions at √s=200 GeV in STAR

STAR Collaboration; Butterworth, J.; Eppley, G.; Geurts, F.; Llope, W.J.; (2014)

We report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2<pT<6 GeV/c in p+p collisions at √s=200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between different models of the J/ψ production mechanism since they predict different ...

J/ψ production at low pT in Au + Au and Cu + Cu collisions at √sNN =200 GeV with the STAR detector

STAR Collaboration; Butterworth, J.; Eppley, G.; Geurts, F.; Llope, W.J.; (2014)

The J/ψ pT spectrum and nuclear modification factor (RAA) are reported for pT<5GeV/c and |y|<1 from 0% to 60% central Au+Au and Cu+Cu collisions at √ sNN =200GeV at STAR. A significant suppression of pT-integrated J/ψ production is observed in central Au+Au events. The Cu+Cu data are consistent with no suppression, although the precision is limited ...

J/ψ production cross section and its dependence on charged-particle multiplicity in p + p collisions at s=200 GeV

STAR Collaboration; Brandenburg, J.D.; Butterworth, J.; Eppley, G.; Geurts, F.; (2018)

We present a measurement of inclusive J/ψ production at mid-rapidity (|y|<1) in p+p collisions at a center-of-mass energy of s=200 GeV with the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The differential production cross section for J/ψ as a function of transverse momentum (pT) for 0<pT<14GeV/c and the total cross section are ...

Jacobi-like Matrix Factorizations with CORDIC-based Inexact Diagonalizations

Hemkumar, Nariankadu D.; Cavallaro, Joseph R. (1994-06-20)

We propose a CORDIC-based Jacobi-like method for parallel computation of the eigenvalues of Hermitian (and real symmetric) matrices and the SVD of real matrices using inexact diagonalizations. It is predicted on the fact that exact diagonalization is not necessary for convergence and the potential increase in computation time due to concomitant ...