Science is not a set of answers to all questions

Interview, 18 November 2020

The website “Troitsky variant – Nauka” published a large interview with Deputy Head for Science of the Accelerator Department of the Laboratory of High Energy Physics JINR, Candidate of Physics and Mathematics Anatoly Olegovich Sidorin. Interviewed by Jan Machonin.

We offer to your attention an extract from the interview the full version of which is available via the links (in Russian): part 1, part 2.

Science is not a set of answers to all questions

You have been working at JINR since 1995, and have been recently participating in the creation of the new NICA particle accelerator at colliding beams. How did this project start?

The NICA project started thanks higher officials on the initiative of JINR Director Alexei Sissakian, since about 2005. First discussions took place even earlier. Mr Sissakian was trying to find ways out of the difficult situation the Institute was in. It required large-scale projects in Dubna that would be able to attract the Member States, firstly, and which would be interesting in terms of science and their applied use. He considered three possible projects: the IBR-2 modernization in the Laboratory of Neutron Physics, the creation of a new cyclotron complex in FLNR, and a project on fundamental science he was engaged in as a theoretician, namely the NICA project. The first question in the NICA project was whether the Nuclotron was able to provide the design parameters. At that time, the Nuclotron was not financed, in fact: there were no funds for its normal development and operation. In 2007, work started on its modernization to answer the question. It was Sissakian’s personal initiative: he found all possible funding sources, and the project started to develop thanks to him. Sissakian also found a worthy supervisor of this activity: Grigory Trubnikov who performed heroics. He spent the first two or three years of life at the complex in a constant fight to ensure normal working conditions for employees. The project came from top officials so ordinary staff members did not trust it at first. The Directorate did not understand that there was nearly a technological catastrophe: there was no appropriate vacuum system of the accelerator, there was no power supply system of our own (we used sources that had once operated at the Synchrophasotron). It was an accelerator that did not have a part of systems: so, specialists used everything at their hand during the launch.

Do you remember the turning point when it became clear that everything was going to develop, that everything was going to work out?

In 2009, the Scientific Council approved the NICA project and the Committee of Plenipotentiaries of the JINR Member States adopted it. And in 2011, 2012, major results of modernization of the Nuclotron were demonstrated. Two indicators were achieved that were outlined by Director Sissakian as success criteria: ions with atomic number more than 100 were accelerated, and the operation of the magnetic system with the design field was demonstrated. Although the state of the Nuclotron at that time, of course, still left much to be desired, radical changes began to happen and people believed in the project. These were not just political claims.

The tasks of fundamental studies at the NICA complex include the creation of baryonic matter, quark-gluon plasma. Could you please explain what is the essence of it?

In the 1960-1970s, scientists found out that the proton and the neutron are not elementary particles and that they consist of quarks. Nobody has ever observed free quarks, but now we are sure that quarks do really exist. For some reason, all quarks in our world are grouped and cannot be separated from each other. However, there are some states of matter at which they behave as free particles. One of such states called quark-gluon plasma (gluons are particles providing interaction between quarks) was discovered in the early 2000s. The plasma cannot be directly observed. It is possible to observe only the consequences caused by its existence. There are many opinions about this discovery, various interpretations of the results of experiments, but science is not a set of answers to all questions. On the contrary, the answer to any question generates hundreds of new questions, and science is a set of topical questions to be answered. The discovery of quark-gluon plasma made it possible to search for answers to many questions, like how do its properties depend on the density and temperature of matter? under what conditions does the transition from ordinary matter to quark-gluon plasma take place? how does this transition occur? Our Dubna theoreticians were actively developing the idea of a certain transition region. It is assumed that there must be a mixed phase (and this is mainly the prediction of our theoreticians) in which there are particles of ordinary matter and free quarks and gluons. The NICA collider’s parameters were chosen so that to ensure the birth of such a mixed phase during the collision of accelerated gold nuclei. It is one of the fields of the NICA scientific programme.

The second part of the programme includes spin physics…

It is also a successor of the long-term development of our Laboratory. Around the beginning of the 1980s, scientists began to accelerate polarized deuteron beams at the Synchrophasotron. In terms of beam parameters, the Synchrophasotron was a fairly impressive facility in the world around which an authoritative school of spin physics formed, which, fortunately, has not completely disappeared yet. Representatives of this school defined the second task of the NICA collider. There are lots of interesting tasks in spin physics but the possibility of their solution depends, first of all, on those beam parameters that can be provided by the accelerator. In 2016 – 2017, we had two runs at the Nuclotron with polarized beams, and this was the revival of the spin programme in the Laboratory after 13 years of complete silence. These 13 years were spent to create a new ion source, to prepare the infrastructure for its normal operation. The maximum parameters have not been achieved so far but we believe that plans for spin physic studies at the NICA complex are quite realistic.

Does that mean that work is on the enthusiasm wave?

When the project started, specific performers were very dependent on the Institute’s management as far as JINR heads provided funding only thanks to their efforts so that the project could develop. Nowadays, after defining the frames of its implementation, funding issues have been almost resolved. There may be some local problems but they are resolved routinely. Now, the main goal is to use allocated funds as efficiently as possible and in the shortest possible time. The nature of tasks has changed. It’s one thing if funding is acquired thanks to efforts, then enthusiasm is required. But if the project is being implemented, a systematic accurate work is required, which is, in fact, far more difficult. The first stage is easier, more rewarding. One contributes efforts and sees how his deal is evolving. And when it happens, it should be filled with something. And that means working hard every day.

Please, speak about the applied programme of the NICA collider…

The Russian Federation takes part in the creation of the NICA complex as in a mega-science project implemented in the territory of the Russian Federation, not least because of the opportunities for applied use of produced ion beams. There are no centres left in the Russian Federation where beams with such parameters can be produced. And there are only three or four such centres in the world. The range of applications of such beams is wide, for example, research on the radiation resistance of microchips, and Roskosmos is most interested in it. Moreover, it may be used for studies on radiobiology. It is planned to develop technologies for radiation medicine: to produce the required radiation dose field, certification methods, etc. Our complex is not designed for curing patients: the beam is too expensive, and it is impossible to meet all the medical requirements. However, proton and carbon beams with necessary parameters will be provided. One more application field is related to the development of technology for nuclear fuel waste processing.

Is it planned to use the collider as a source for controlling a nuclear reactor?

No, it is not. It is not a task for the NICA complex. Nuclear reactors require a collider providing beams with a power of several megawatts in a continuous mode. The average beam power at the Nuclotron output is measured in watts, not megawatts. It is negligible even to study prototypes of real energy devices. However, it is possible to search for the optimal energy range, to study neutron distribution inside the irradiated sample, i.e. to study the issues not related to the technology but rather to the concept of the operation of the accelerator-controlled reactor. And it is planned to carry out such activities at the NICA complex.

What do you think is the main interest in the NICA accelerator for the international community? How will it differ from other existing accelerators? Can the NICA launch change somehow the nature of the Institute? Will it make JINR more international?

The interest of the scientific community in the project is related, of course, to the fundamental research programme, first of all. There are several facilities around the world that already exist or are being constructed for similar goals. However, NICA has a chance to be the best facility in the world for several years in this physics domain. That is why foreign scientists take an active part in the international collaborations established around the main experiments, and we are waiting for them for runs when the complex will be launched. Accelerator specialists are interested in NICA as far as Russia is coming back to accelerator physics with a large-scale project after almost a quarter of a century of silence. And our foreign colleagues are enthusiastic about helping us with numerous technical issues. However, NICA is by and large is a modest, we may say “chamber” project at the scale of human civilization, a small facility. Although its potential may be sufficient for the Nobel Prize discoveries. It will significantly improve the JINR image but will not change it radically. Of course, we hope that the first run at our collider will attract the attention of the world community, including in the Member States.

Is free access to the data, like that provided at the LHC at CERN, planned?

In terms of information openness, our accelerator complex operates almost in the same way as the LHC. For example, it was interesting for me to watch online what was happening to the beam during the runs at CERN. We also share the key parameters of the Nuclotron on the Internet with free access during runs. The difference is in scales and maybe in the details of the provided information. We plan to work in the same way at the NICA collider.

How important is NICA for science in Central Europe?

In my opinion, the countries of Central Europe have already overcome the economic difficulties of the transition period in the economy. Interesting scientific projects are emerging, radiation medicine is developing, new research facilities are being created. And one of the main problems is staffing these programmes. It is a common problem of the entire world community caused by the decline in social interest in engineering. However, this problem is aggravated for the many JINR Member States by the fact that there is no appropriate infrastructure for training specialists. And NICA can help with it. Any facility of such a class is a kind of a university for training highly qualified staff. The project includes a development programme for at least 10-15 years ahead with several consecutive upgrades. For example, our collider will start operating in a certain initial configuration of equipment, and while research will be carried out at it, equipment for the next upgrade scheduled in two or three years will be designed and produced. It is exactly the period necessary to prepare a master’s or a PhD thesis. At the same time, the optimal operating mode assumes that the personnel of the Laboratory is engaged in the accelerator use, and new systems are developed by young people who have an opportunity to master the entire cycle of modern equipment development, starting from the conceptual design and ending with tests at an operating facility. Moreover, they master the most advanced modern technology with a wide range of applications not only in physics but in other sectors of the national economy as well. JINR is a joint institute for all the Member States, its equipment is available for the youth from any of them if there is a need for such personnel and good technical universities. And these are primarily Poland, Ukraine, the Czech Republic, Belarus, Bulgaria, Romania, Slovakia, and, in fact, all the countries of Central Europe.

We do not have enough staff members yet to ensure the implementation of all the planned experimental studies that is why many people consider the staff training programme as the NICA staff training programme. But this is not quite true: it is not necessary to come to Dubna for a long time (although we will be glad to employ any talented person): we will ensure that a person does interesting and challenging work here and then the acquired diploma will allow them to find an exciting job in their countries.

How do you view the future of physics in general?

The increase in particle energy, and subsequently in the size of accelerators, has been the main field of accelerator physics for the last several years. Scientists constructed accelerators not to solve some specific tasks but to acquire the maximum energy. So, in this era, many people waited for major fundamental results in the fields of particle physics that was called “high energy physics”. This allowed creating the modern microworld theory, a so-called “standard model”. Experiments at the world-largest accelerator have shown that all its predictions are proven with unprecedented accuracy by accelerator experiments, and we can expect some deviations only by building a Solar system-sized accelerator. In this regard, accelerator physics has come to an end. But only in this regard. Physics is undergoing a serious structural adjustment. The interest shifts gradually from research on particle properties to studies on the properties of complex objects consisting of a large number of particles, the properties of each of them separately are already well-known. Accelerates may be used for this but their energy should correspond to a particular task, and the construction of them should provide the most favourable conditions for observations. And it does not have to be giant facilities like the LHC. The dinosaurs era in science is passing, they have completed their task and are doomed to extinction. They are being replaced with small, agile, and smart mammals. One of the illustrations of this process is the NICA project.