by Panos Charitos. Published: 28 June 2015

Following his graduate studies in physics at Warsaw’s University of Technology, Jeremi Niedziela decided to apply for CERN PhD Student’s scheme and he was accepted last year. He is currently working on his PhD thesis on baryon correlations under the supervision of Adam Kisiel.

As an undergraduate student, Jeremi has been interested in the field of subatomic physics: “I have always been fascinated by the study of the structure of matter and the interactions that shape matter and wanted to learn more about this field. That left me with two options during my studies: either to work with group studying the structure of nucleus or join the group of Adam Kisiel that had a long tradition in heavy-ion physics and is participating in ALICE”. Working in one of the world’s largest and most complex experiments and probing matter at scales very close to the Big Bang was a big challenge and hence Jeremi decided to join Adam’s group during his third year of studies.

That was the time that he first arrived at CERN on a three-month internship. Under the supervision of Adam and Małgorzata Janik he worked on studying angular correlations and with the results he obtained during that period he successfully completed his BSc thesis. He then decided to apply for a Master diploma shifting to a different subject; namely baryon correlations which is also the topic of his PhD.

Following his internship at CERN he decided to apply for CERN’s doctoral students programme. He was selected by the ALICE DAQ group and for his thesis he will work both on some physics analysis as well as on development of the Event Display system of ALICE.

We asked Jeremi what motivated him to move to this particular field and he explains: “by studying baryon correlations we are able to extract some parameters for the QCD theory that are needed to better understand the nature of strong interactions. The parameters are the scattering length and the effective range for different pairs of baryons”. Jeremi has been working on a general model that will allow studying effectively these parameters from the data that ALICE will record during Run2 where a better statistics is expected due to the beam conditions. If this is the case then we could get a much better understanding of the behaviour of strong interaction as the medium formed in lead-lead collisions expands and cools down.

At the same time Jeremi is responsible for the Event Display of ALICE like those that were produced after the recent 13 TeV proton-proton collisions at the LHC. One of the requirements he had to tackle was the need to separate the visualization of the data from the reconstruction. There was a need to disentangle the two processes in order to avoid errors appearing during the reconstruction affecting the visualization and vice versa. The Offline team had already started working on this problem developing large parts of a new code that was finalized and implemented by Jeremi under the supervision of Pierre Vande Vyvre and Barthélémy von Haller.

Watching the first event displays appearing in the large screens in the new ALICE Run Control Centre has been a rewarding moment for the team. Everything seemed to run smoothly and Jeremi shared the excitement of his colleagues seeing the LHC back in action after a period of 27 months.

Jeremi now continues working on developing tools that will allow the visualization of data from the High Level Trigger (HLT) adding an option to switch the type of data that one can visualize. At the same time he is working with Adam Kisiel on preparing his first paper as a PhD student that will be submitted in a review journal. Finally, he cooperates with the CERN Media Lab which works on developing what is called "Total Event Display" – a common event display for all experiments. He is responsible for providing data and geometry of ALICE to the Media Lab in order to be visualized within this new type of event display.

We warmly wish Jeremi to gain many experiences and wisdom as his CERN adventure continues.