Scientific results:
Activity of stars with planetary systems in young clusters and associations were investigated, and a comparison of the values of parameters characterizing the area of spots with effective temperature and the objects rotation periods was made.
Studies of the activity of stars with planetary systems based on observations from the TESS space mission have been carried out. The activity of a TOI 837 system of spectral class G0/F9 star in the cluster IC 2602, about 35 million years old were investigated. The results of studying the sunspot activity of 11 K-dwarfs with established planets in the habitable zone according to the archive of the Kepler space telescope are presented. The investigation results of the activity of a spectral class K7 Gl 414A dwarf with two planets were presented. The results of an analysis of the activity of theWASP-193 spectral class F9 star with a super-Neptune type planet are presented.
A set of kinetic Monte Carlo models was developed, which made it possible to calculate in detail the kinetics of the processes of formation, transfer and relaxation in collisions of thermal and suprathermal atoms in excited states in the upper atmospheres of hot exoplanets for the first time. To study the rate of atmospheric loss of hot Neptune GJ 436 b, calculations were carried out using a previously developed self-consistent 1D model of a hydrogen-helium atmosphere, which takes into account the gas kinetics and heating by suprathermal electrons.
In the vast majority of previous atmosphere evolution studies of hot sub-Neptunes, attention was paid only to thermal processes of atmospheric loss. Non-thermal atmospheric loss processes are usually not included in aeronomic models, but our previous studies of non-thermal atmospheric loss of hot sub-Neptunes GJ 436b, GJ 3470b; Pi Men c, carried out by the laboratory, showed that non-thermal losses of the atmosphere due to exothermic photochemistry can be comparable to the rates of thermal losses under conditions of a quiet host-star and these processes should be included in aeronomic models of the upper atmospheres of sub-Neptunes. An important step in creating an aeronomic model is the necessity to take into account non-thermal losses due to the influence of stellar wind plasma on the hot exoplanet extended upper atmosphere.
The planetary atmosphere expands due to heating by the hard XUV radiation of the host star; it interacts with the stellar wind, which shapes the geometry of the gas envelope of the hot planet and the structure of the atmosphere. These different structures can be found in the Ly-alpha lines because they contain a significant amount of neutral hydrogen. The kinetic model of the upper atmosphere aeronomy of an exoplanet was extended by including the stellar wind plasma influence on the extended hydrogen corona of a hot sub-Neptune. For this purpose, previously developed kinetic Monte Carlo models were used to study the precipitation of high-energy protons and hydrogen atoms into planetary atmospheres.
The kinetic model was adapted to the upper atmospheres of hot sub-Neptunes, which made it possible to calculate the rate of stellar wind plasma energy absorption in the planetary corona and to refine estimates of non-thermal atmosphere loss rate due to the influence of the stellar wind of the parent star.
This approach to studying the hot exoplanets atmospheres evolution is an integral part of aeronomic and kinetic models complex developed within the laboratory’s tasks, designed to estimate the rate of atmosphere loss due to thermal and non-thermal processes for hot transition-class planets: sub-Neptunes and super-Earths.
Calculations continued using a self-consistent 3D multifluid hydrodynamic model to study the aeronomy of the expanding hydrogen-helium upper atmosphere exposed to the stellar wind. A comparison of the model results of atmospheric loss rate calculations with estimates obtained from observations using ground-based and space telescopes was made.
Adaptation of three-dimensional gas-dynamic and MHD codes was carried out for their use in modeling the shells of less massive planets: sub-Neptunes and super-Earths. The approximation model, previously used to calculate the mass loss rate of a model hot sub-Neptune, was also used to estimate changes in mini-Neptune HD 207496b atmospheric mass loss rate in the approximation of the gas planet hypothesis and agreement with the results of calculations by other authors was obtained.
Implementation of research results:
Development of recommendations for a scientific core program for the observations of exoplanet atmospheres with the Spektr-UF space telescope: it is proposed to pay attention to multiplanetary systems, which are ideal laboratories for exoplanetology, since they provide a unique opportunity to compare exoplanets that formed in the same protoplanetary disk and are illuminated by the same star.
As an example, studies on the activity of the object L 98-59, located at a distance of 10.6 pc from us and possessing a multiplanet system (one of the planets L 98-59 b is a rocky planet with a mass not exceeding the mass of Venus) were carried out. Observations of potential exo-Venuses could help confirm hypotheses about Venus's past, as well as the incidence of Venus-like planets in other systems. In addition, data from future missions to Venus, such as DAVINCI, EnVision and VERITAS, will provide valuable information about Venus, and the study of exovenus with the WSO-UV space telescope will complement the data from these missions.
Organizational and infrastructural changes:
Work on the construction of a high-resolution fiber optic spectrograph for the 1-m the Simeiz INASAN Observatory telescope.
Education and personnel occupational retraining:
Annual International Schools “Exoplanet Research” for young scientists and students and All-Russian Conferences – “Research of Stars with Exoplanets” were held.
New educational programs developed and implemented by members of the laboratory’s research team in the declared area of scientific research:
Program "Introduction to exoplanets", author V.I. Shematovich, master's program, Department of Space Physics, MIPT (SU)
Program “Geophysics and Physics of Planets”, author V.I. Shematovich, specialty program, Faculty of Physics, Lomonosov Moscow State University.
Under the guidance of the leading scientist and key laboratory employees, student employees received two bachelor's degrees, a master's degree, and a specialist's diploma.
Two PhD dissertations on the topic of the project were obtained.
Cooperation:
- Institute of Space Research RAS
- Institute of Laser Physics SB RAS
- Novosibirsk State Technical University (joint research)
- Special Astrophysical Observatory of the Russian Academy of Sciences (creation and implementation of a high-resolution fiber optic spectrograph)
- Sternberg State Astronomical Institute, Lomonosov Moscow State University.
