# QM 2011 - XXII International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

May 22 – 28, 2011
Centre Bonlieu
Europe/Zurich timezone

## Probing nuclear matter with jets and $\gamma$-hadron correlations: results from PHENIX

May 24, 2011, 5:00 PM
20m
Salle de l'Europe (Imperial Palace)

### Salle de l'Europe

#### Imperial Palace

Allée Impérial 74000 Annecy, France Tél. : +33 4 50 09 30 00
Parallel Jets

### Speaker

Dr Nathan Grau (Augustana College)

### Description

Fully reconstructed jets and hadrons correlated with a direct photon significantly reduce energy-loss bias, the bias toward measuring particles from partons which suffer little energy loss. In d+Au collisions, one accesses the physics at large $x$, which yields important constraints for nuclear parton distribution functions. In both d+Au and A+A collisions, coherent multiple-scattering models of energy loss can be tested. In this contribution, we present the current results from the PHENIX experiment on fully reconstructed jets and direct $\gamma$-hadron correlations. Baseline measurements of jets in p+p collisions as well as their yield and correlation modifications in d+Au and Cu+Cu will be given. From $\gamma$-hadron correlations, we present the fragmentation function in p+p and Au+Au collisions and its modification in Au+Au to lower $z_T$ than what has previously been studied. Implications of this data on our understanding of both cold and hot, dense nuclear matter created at RHIC are discussed.

### Primary author

Dr Nathan Grau (Augustana College)

 Slides