(Anti-)(hyper-)Nucleus Production and Exotic Baryon States searches with ALICE at the LHC

by Natasha Sharma (University of Tennessee)

Thursday 5 Mar 2015, 15:00 → 16:00 US/Eastern

Universe

In ultra-relativistic collisions at the Large Hadron Collider (LHC) light (anti-) (hyper-)nuclei are produced with significant yields, especially in collisions between lead nuclei. In addition, these collisions allow searches for light exotic bound states of baryons. Light nuclei are identified using the excellent particle identification capabilities of the Time Projection Chamber (TPC) and the Time-Of-Flight (TOF) detector of the ALICE experiment. The transverse-momentum spectra and yields of light (anti-) nuclei such as deuteron, helium3, and hypertriton produced in pp, p-Pb and Pb-Pb collisions will be presented. Thermal model calculations with chemical freeze-out temperature of about 156 MeV well describe the light nuclei and hadron yields. This is very surprising as weakly bound nuclei e.g. hypertritons were thought to be destroyed by collisions at these temperatures. The reasons for the success of the thermal model will be discussed. The results will also be compared with the coalescence model. Finally, latest results from searches for weakly-decaying light exotic states, such as the Lambda-Lambda (H- dibaryon) and the Lambda-neutron bound states will also be presented.