July 28, 2020 to August 6, 2020
virtual conference
Europe/Prague timezone

Investigating the hyperon-nucleon strong interaction with a precision measurement of the hypertriton lifetime in ALICE

Jul 31, 2020, 9:55 AM
virtual conference

virtual conference

Talk 06. Strong Interactions and Hadron Physics Strong Interactions and Hadron Physics


Francesco Mazzaschi (Universita e INFN Torino (IT))


The hypertriton is a bound state of proton, neutron and lambda. Studying it provides insights about the strong interaction between the lambda and ordinary nucleons. In particular, the hypertriton is an extremely loosely bound object, with a lambda separation energy E$_{\Lambda}$ of 150 $\pm$ 8 keV. One way to investigate the hypertriton's internal structure, and thus hyperon-nucleon interactions, is to measure the hypertriton lifetime precisely.
In the past, these measurements had large uncertainties and did not give a clear answer. However, thanks to the very large set of Pb-Pb collisions collected during the run 2 of the LHC the ALICE collaboration has performed systematic studies on the hypertriton lifetime. Both the two and three body decay channels have been studied with the help of machine learning techniques for the signal extraction.
The precision of the new ALICE results on the hypertriton lifetime is comparable with the current world average, thus providing strong constraints on models describing hyperon-nucleon interactions.

Primary author

Francesco Mazzaschi (Universita e INFN Torino (IT))

Presentation materials