Overcoming challenges: for which a scientist from NRNU MEPhI received an award at CERN
Daniil Ponomarenko, an engineer at the Department of Elementary Particle Physics (№ 40) of the National Research Nuclear University MEPhI, received an Outstanding Achievement Award in front of the ATLAS collaboration, which conducts experiments at the Large Hadron Collider (LHC) in CERN. What contribution of the Russian physicist has been marked with a prestigious international award? What qualities does a scientist need who wants to work at the forefront of science? Daniil Ponomarenko told about this to the correspondent of the project "Social Navigator" by Russia Today.
- Daniil, please tell us why you were awarded the prize?
- The ATLAS Collaboration has been awarding its members with the Outstanding Contribution Award for the past few years. Every year 10-15 people from about 5.5 thousand employees become laureates.
Of course, for ATLAS, the contribution of each specialist to the common cause matters. But priority is given to works that solve critically important challenges and allow the entire collaboration to move on - collecting new data, discovering "new physics" and so on. This can be, for example, the development of a new data storage format or a new trigger. Such "breakthrough" achievements are awarded with prizes.
I was awarded the prize as part of an international team of seven, which, in addition to myself, includes graduate students and young scientists from several prominent US universities. We are working on the provision and modernization of work of the TRT detector in the ATLAS experiment.
- What is this detector?
- The TRT detector is one of the subsystems of the ATLAS experiment. It tracks the particle track, measures their momenta and carries out their identification - are there transition radiation photons, electrons or some other types of particles among them. That is, it is a very important part of the overall system. A great contribution to the creation of the TRT detector was made by the Department of Elementary Particle Physics (№ 40) of the Institute of Nuclear Physics and Engineering, NRNU MEPhI, in particular, one of its founders, Boris Anatolyevich Dolgoshein.
In general, ATLAS can be compared to a photocamera. A conventional photocamera collects light, records where the photons flew, and reconstructs an image from this. ATLAS, on the other hand, is directed to the microcosm, and it registers elementary particles - mainly decay products of unstable particles that were born in the collision of protons in the very center of the experiment.
Continuing the analogy with a photocamera, I note that modern cameras can shoot at 120 frames per second and maybe a little more. In our case, we continuously make 100 thousand frames per second, but not all "frames" are interesting from the point of view of physics. Many are reflections of well-studied processes, while others are similar to the very rare events that we hunt for. To select events, we have a trigger selection system at our disposal. And here we come to the reason why the collaboration celebrated our work.
Initially, when the TRT detector was created, it was assumed that the number of collisions at the center of the ATLAS experiment would not exceed about 20 "proton-proton" pairs. This provided an initial estimate of the required throughput for the data stream from the detector. But the situation has changed, now we collide more than 50 "proton-proton" pairs per event. Consequently, the number of tracks left in the TRT detector increases, and the number of trigger requests to save event data as interesting increases. As a result, the data flow has grown massively.
This bid defiance to a system that was not originally designed for such use. Of course, during the design and construction stage, the TRT detector was built with a safety margin, but it was not at all designed for today's operating conditions and load.
- What the challenge is your research group solving?
Our team managed to optimize the software, upgrade the electronics and take almost everything possible from the margin of safety. Overall, we are doing maintenance and optimization the TRT data acquisition system so that it can successfully measure in harsher conditions, with increased loads and increased trigger readout rates.
We have specialists who deal only with "hardware", but I am more involved in "software", although sometimes I have to perform other tasks - test equipment, change electronics…
- How did you get to CERN?
- I completed my bachelor's and master's degrees at NRNU MEPhI, entered graduate school, then continued my studies in a joint postgraduate study with Radboud University in the Netherlands in the direction of high energy physics. I am currently working on a dissertation on checking of the Standard Model and plan to defend it shortly.
I joined the ATLAS collaboration, the group of my scientific advisor Anatoly Samsonovich Romanyuk, in 2015. In those time I was asked to work on the data collection system, restore the testing bench and help the scientific group with preparing the detector for modernization. I liked the projects, since then I have continued to work in this direction.
After defending my thesis, I plan to continue working on the TRT detector. We will start the next dataset in the spring of 2021 and for now we plan to finish it by the end of 2024. Further, in the ATLAS collaboration, a large-scale modernization of the experiment is planned, and until that moment I will be engaged in ensuring the full operability of the detector.
- What advice would you give to a student who wants to get to Large Hadron Collider (LHC)?
In MEPhI they like to say that the road will rise to meet the one who walks it. First, you need to understand what you want from life. Our work can be as crazybly interesting, but also very difficult. From time to time you have to deal with very monotonous, boring things, solve very urgent and difficult problems. In addition, there is a lot of internal competition in collaboration, and if you miss the initiative, someone else will immediately pick up your work, and you will be left on the sidelines. To be on the cutting edge of science and to keep up with everything, you have to constantly run very quickly, develop, and many are exhausted from this.
In addition, a lot depends on what exactly you plan to do. If you are interested in data analysis, then you will have to spend a lot of time programming. You must be a good physicist, but you must also have strong programming and data science skills. If you want to work directly with the detector, then in addition to understanding how the equipment works, you will definitely need knowledge of the physics that your detector is hunting for.
In any case, you will need to understand several areas of science, and sincerely love them, because you will spend a lot of time in each of them. Nevertheless, this is an interesting path, and one can start moving along it at MEPhI, where many departments participate in experiments at the Large Hadron Collider (LHC).
- In what course do students begin to engage in scientific work?
- Usually students start scientific work after the second year. At our department, we gradually, from simple to complex, bring up to date, tell how the collider is organized, how detectors work, how data analysis is done, prepare them for experimental work. We have special courses in statistics, particle physics and other branches of physics. Therefore, our department produces well-trained specialists who can make a significant contribution to research.
- Today many physicists work in collaborations. Is it true that in such huge teams it is difficult to distinguish oneself, to make a noticeable personal contribution to a common cause?
- Indeed, working alone, in many ways, has already ended. CERN was created in the 1950s precisely because no country on its own could handle the necessary huge projects, and for their implementation it was required to combine scientific teams and scientific capacities.
The life of the ATLAS experiment, in which I participate, consists of titanic stages: starting with the development and creation of detectors for subsystems, their installation at the Large Hadron Collider, commissioning, software development, to obtaining data from a physical experiment, processing them, dozens of checks by hundreds of scientists from all over the world and, finally, publication of the results.
Some of these steps are repeated many times, including right now. Pitfalls regularly arise and a tremendous amount of time and effort is spent on overcoming them for each employee. Nevertheless, the ATLAS collaboration is trying to distinguish some scientists and motivate them additionally.
We see that partnerships between universities usually give very good results: someone is good at one, someone is good at another, and all this serves to achieve common goals.
Source: RIA Novosti