https://doi.org/10.1140/epjc/s10052-012-1877-5
Regular Article - Theoretical Physics
Spin correlations of 
pairs as a probe of quark–antiquark pair production
1
Theoretical Particle Physics and Cosmology Group, Physics Department, King’s College London, Strand, London, UK
2
Theory Division, Physics Department, CERN, 1211, Geneva 23, Switzerland
3
Department of Physics, Sejong University, Seoul, 143-747, South Korea
* e-mail: dshwang@sejong.ac.kr
Received:
5
September
2011
Revised:
15
January
2012
Published online:
7
February
2012
The polarizations of Λ and 
are thought to retain memories of the spins of their parent s quarks and 
antiquarks, and are readily measurable via the angular distributions of their daughter protons and antiprotons. Correlations between the spins of Λ and produced at low relative momenta may therefore be used to probe the spin states of 
pairs produced during hadronization. We consider the possibilities that they are produced in a 3P0 state, as might result from fluctuations in the magnitude of 
, a 1S0 state, as might result from chiral fluctuations, or a 3S1 or other spin state, as might result from production by a quark–antiquark or gluon pair. We provide templates for the 
angular correlations that would be expected in each of these cases, and discuss how they might be used to distinguish production mechanisms in pp and heavy-ion collisions.
© Springer-Verlag / Società Italiana di Fisica, 2012
