The secret of binary star V1309 ****************************************************************************************** * The secret of binary star V1309 ****************************************************************************************** Last year, three young researchers at Charles University won the Neuron Prize for promisin the Czech Republic. One of them was astrophysicist Ondřej Pejcha, an expert on binary star CU and at Princeton University. What was it like to win a Neuron Prize? Does it have a reputation among Czech scientists a I was really happy about it and I appreciate it very much. It’s a recognised award and the received it before me have my respect and admiration. I already knew about the Neuron when USA. You have been described as one of the “most talented astrophysicists” by the council of th What prompted you to return to Charles University from Princeton? The internal Primus programme made it possible. That created a place for me and ensured th my team. I came in September 2017 and a year later I received a so-called starting grant f Research Council (ERC) to study interactions of binary stars. You’d been abroad for several years; how did you find things upon your return? Some things really pleased me. I am very happy, for example, that my colleagues from the I Theoretical Physics at the CU Faculty of Mathematics and Physics are very inquisitive and capable scientists. They’re working on different problems than I, so we cannot discuss the work right away, but they quickly understand what the problem is. A large part of the research at our institute focuses on the theory of gravity, the genera relativity, and the physics around compact objects such as neutron stars and black holes. a group here working on quantum physics, which recently hired Zdeněk Mašín after a doctora and a postdoc in Germany with a Primus project. Our groups are related to each other by do on supercomputers. After all, I invested part of the money from the ERC grant into the exp computing cluster at the Faculty of Mathematics and Physics in Karlín. What did you find less than optimal? Are there areas that the university should improve? It’s hard to take a general position because I get the impression that the situation varie individual faculties and departments. The university is divided into a large number of fac one often consists of many departments. With so many voices, it’s hard to find the necessa to coordinate cooperation on larger goals. I also think that many departments and Charles a whole lack consensus on a truly long-term and detailed vision of development over a peri years. You’re primarily a scientist, but last year you told me you also wanted to teach. I advise one bachelor student and two master students, which I enjoy. I’ve also been teach class: the astrophysics of gravitational wave sources. It’s related to the spectacular det detected gravitational waves for the first time in September 2015, which saw those behind receive the Nobel Prize two years later), but I focus more on what gravitational waves rev about celestial objects. I try to teach a little differently: with my students we’ve tried interactive teaching, panel discussions, papers, literature reviews… My goal is to show st issues, how the scientific method works and that results are often not as polished to deta the textbooks. The paths to knowledge are often quite tortuous and many interesting and im are left unresolved in the end because ideas and experiments run out. Are there any differences between students in the USA and here? My limited impression is that our students are ahead of those abroad in depth of knowledge behind in soft skills: in the ability to communicate, which is also related to thinking ab where they’re heading. Even for me, during my doctoral stay in Ohio it wasn’t easy at firs these abilities, but there were classes to work on these issues. For example, we had a cla magnitude astrophysics, where a randomly selected student would go to the blackboard and w thoughts and ideas for the solution from other students, so there was also teamwork and co How has your research into binary stars progressed in Prague? In 2019, we wrote several articles both with people from our team and with foreign co-work our team grew by two postdocs and two students. We focused on theoretical models of gas an as well as the transport and emission of radiation, which is our main source of informatio in the Universe. The idea of the project is to understand one of the phases in the evoluti stars, called the “common envelope phase,” when two stars start to interact so strongly th into a single object, or shrink their orbit significantly. This is probably the most impor the evolution of interesting binary stars, such as those composed of black holes, neutron dwarfs. The phase is essential for the formation of sources of gravitational waves. Is this just a theoretical model, or have we as humanity observed something like this alre Astronomers observed one case where it was extremely clear that two stars merged. A binary observed, noticeably shortening its orbital period, followed by a flare-up and brightening this object for several years. Its name is V1309 Scorpii. Do you still dream about it? Not any more (laughs). That stopped after I came to Troja and published an article explain observations of this object. That was also the basis of my ERC grant. . Tell me more about the members on your team: who are they? Our group is made up of three postdocs, two master students, a bachelor student, and mysel looking for a doctoral student and we’re gradually coming to a natural change of postdocs three-year stints. We have four years of the ERC grant left, during which I anticipate tha successful scientists will become part of the team. What would you advise colleagues who want to apply for such a grant? Aside from the usual lessons, like that the application has to answer a number of basic qu this topic, why you specifically and why now – with the ERC I would advise that they reall “high risk, high gain” threshold. From my point of view, the project design was a lot risk other thing I’d ever written. The committee appreciated that, but then you’re afraid that the conclusion that you can’t fulfil it. Will you try for a higher academic rank in the Czech Republic? It’s probably necessary. The local academic system requires associate professorships and p it’s also important for access to students, accreditations and so on. I want to habilitate In one interview, I was interested to learn that you described your advisor from Ohio, Pro Thompson, as a great role model. He was a different type of scientist than anyone I’d known before that from the Czech Repu me with his curiosity and the style of work, his original ideas, and an effort to take eve higher level. At the beginning of my doctorate I found it interesting that people in the d were each successful in a completely different way. Todd was an excellent mentor. ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ Ondřej▒Pejcha▒(35)▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ Ondřej Pejcha, Ph.D., is a theoretical physicist and astrophysicist who won an ERC startin in his study of astronomy at Ohio State University (Ph.D. 2013). He then worked as a postd thanks to the Primus programme. He is the author of around 30 studies; he is raising two c