by Panos Charitos. Published: 31 January 2014

In the past few years, ALICE has published a wealth of scientific results deepening our understanding of the Quark Gluon Plasma and strong interactions and showing how exciting is the field of heavy-ion physics at the LHC.

This is also reflected in the number of students who decide every year to pursue a career with ALICE and apply for a PhD.

In this issue of ALICE MATTERS we focus on Xianguo Lu and Rongrong Ma who recently submitted their thesis following their research with ALICE.

Xianguo Lu submitted his PhD in the University of Heidelberg under the supervision of Prof. Johanna Stachel. His thesis on “the performance limits of the ALICE Time Projection Chamber and Transition Radiation Detector for measuring identified hadron production at the LHC” has recently been awarded the 2013 ALICE thesis award for best technical thesis (http://cds.cern.ch/record/1622225).

Lu says: “I found myself very interested in exploring the performance limits of these gigantic detectors.”


After finding a general parametrization of the TRD signal distribution, he carried out a dedicated measurement of the muon transition radiation.

The momentum resolution of the cosmic rays, measured by the TPC, was improved by a factor of 10 and the signal was observed in the momentum range of 50 GeV/c to 1 TeV/c.

Following this step he started developing a fitting procedure -- the TPC coherent fit -- for particle identification using TPC in the momentum range from 150 MeV/c to above 40 GeV/c.

After defending his thesis last October he is now involved in the analysis of hadron composition of jets; further pushing the particle identification performance at ALICE.

Rongrong Ma defended his thesis last December. Rongrong worked with Prof. John Harris on "Jet measurements in pp and Pb-Pb collisions in ALICE". His thesis focused on the full jet reconstruction utilizing both charged tracks and EMCal clusters measured using ALICE detector in pp collisions at 2.76 TeV.

He explains: “This is the first cross section measuement for jets at this center-of-mass energy.”

Furthemore, in his thesis, Rongron studied the hardon-jet coincidence using only charged tracks to explore the properties of the quark-gluon plasma via "jet quenching".

Following the successful completion of his PhD he recently started his postdoc in the STAR group at BNL, working on the newly-installed Muon Telescope Detector. His research will be focusing on quarkonia productions and correlations in the coming years.

We wish them a successful continuation in their research career. In the next issues of ALICE MATTERS we will introduce a new column for fresh PhD students who worked with ALICE.