# Quark Matter 2018

May 13 – 19, 2018
Venice, Italy
Europe/Zurich timezone
The organisers warmly thank all participants for such a lively QM2018! See you in China in 2019!

## Probing jet splitting and energy loss via groomed jets in relativistic heavy-ion collisions

May 15, 2018, 11:50 AM
20m
Sala Perla, 1st Floor (Palazzo del Casinò)

### Sala Perla, 1st Floor

#### Palazzo del Casinò

Parallel Talk Jet modifications and high-pT hadrons

### Speaker

Dr Ning-Bo Chang (Xinyang Normal University)

### Description

The nuclear modification of groomed jet splitting in relativistic heavy-ion collisions at RHIC and the LHC energies is studied [1] based on the higher twist formalism. Assuming coherent energy loss for the two splitted subjets, a non-monotonic jet energy dependence is found for the nuclear modification of jet splitting function: strongest modification at intermediate jet energies whereas weaker modification for larger or smaller jet energies. Combined with the smaller size and lower density of the QGP medium at RHIC than at the LHC, this helps to understand the groomed jet measurements from CMS and STAR Collaborations: strong modification of the momentum sharing $z_g$ distribution at the LHC whereas no obvious modification of the $z_g$ distribution at RHIC. In contrast, the observed nuclear modification pattern of the groomed jet $z_g$ distribution cannot be explained solely by independent energy loss of the two subjets. The dependence on the angular separation $\Delta R$ between two subjets is also studied; it is found that the nuclear modification of $z_g$ distribution decreases with decreasing $\Delta R$ but the maximal nuclear modification from CMS energies is always roughly twice of that for STAR energies. Our result may be tested in future groomed jets measurements with lower jet energies at the LHC and larger jet energies at RHIC, for different angular separations between the two subjets.

Reference:

[1] Ning-Bo Chang, Shanshan Cao, Guang-You Qin, arXiv:1707.03767 [hep-ph].

Content type Theory Presenter name already specified

### Primary authors

Dr Ning-Bo Chang (Xinyang Normal University) Guang-You Qin (Central China Normal University) Shanshan Cao (Lawrence Berkeley National Lab)

### Presentation materials

 Changnb_jet-splitting.pdf Changnb_jet-splitting.pptx