(P4F2 and P4F2A)
The study program covers all aspects of plasma physics and with extensions to theoretical physics (elementary processes) and to some topics of astrophysics (interplanetary space plasma, dust / ice cloud problems in the solar system) and nuclear fusion. Studies include also borderline disciplines such as plasma chemistry, plasma interaction with solid surface and complex plasma. The program prepares professionals with a broad foundation in mathematics, physics, and computer modeling of physical processes and with deep knowledge of plasma physics.
Research fields are more or less defined by the current projects at our department and it similarly applies to the cooperating institutes of Czech Academy of Sciences.
Space Physics group is involved in a number of space plasma missions and its members interpret the data in following fields:
Plasma Physics group deals with elementary processes and transport phenomena in low-temperature plasma with an accent on diagnostic methods and applications:
It's always a good idea, if you find a topic for you, to contact supervisor first, i.e., prior application!
Supervisor: Doc. RNDr. Petr Dohnal, Ph.D.
Group of Plasma Physics and Numerical Simulations
The dissertation focuses on the study of reactions of simple astrophysically interesting ions with electrons and molecules under conditions close to those prevailing in interstellar space. The apparatus combining microwave diagnostics of plasma with highly sensitive CRDS spectroscopy will be used to study ion-electron recombination. The dissertation will also include the study of reactions of ions with neutral particles in the range of 10 – 300 K using an ion trap. The internal state of ions in the trap can be monitored by action spectroscopy methods such as LIR (Laser Induced Reaction technique).
Collisions of electrons and ions with neutral and charged particles at low interaction energies play a key role in low-temperature plasma in interstellar medium, in laser plasma, but also in plasma used in various technological applications. Recombination of ions with electrons and reactions of ions with molecules are among the fundamental processes and are therefore studied both experimentally and theoretically. The study of these reactions at low temperatures is of particular importance. Under such conditions, the internal excitation of reactants can have a significant effect on the course of the reaction.
The main motivation is the impact of the expected results on astrophysics and the fundamental nature of the interaction of ions with electrons and molecules.
Our department cooperates with foreign laboratories to solve the above-mentioned problem. The project is supported by grants from the GACR and GAUK.
Supervisor: Doc. RNDr. Radek Plašil, Ph.D.
Group of Plasma Physics and Numerical Simulations
The role of negative ions—anions—in interstellar space has been debated for many years. However, anions were only detected in interstellar gas clouds in 2006. They are also found in the gaseous tails of comets and planetary atmospheres. Now their reactions are being studied to explain astrochemical processes.
The proposed work aims to study the reactions of anions with neutral molecules and determine their rate coefficients as a function of temperature. With the equipment available in our laboratory, it is possible to study the reactions of selected anions with neutral atoms and molecules in the temperature range of 10 - 300 K. Simple anions consisting of carbon, oxygen, and hydrogen atoms will be selected for the study. Their reactions with neutral molecules present in interstellar space such as H2, HD, CO and the formation of larger molecular ions will be investigated.
Low-temperature ion trap apparatus and laser absorption spectroscopy will be used for the study. The necessary experimental equipment in our laboratory is fully operational.
Supervisor: Mgr. Oleksandr Gončarov, Ph.D.
Our society heavily depends on modern technologies including global power grids, long pipelines, aircraft routes and on space-based communications that are very sensitive to effects associated with changing solar activity. Probably the most dangerous events are explosive cases in the solar corona (Coronal Mass Ejections, CMEs) that spew out huge amount of ionized matter into the interplanetary space. However, similarly dangerous events can evolve even in a quiet solar wind due to the interaction of solar wind streams with different velocities (Corotation Interaction Regions, CIRs). The long chain of processes connecting events on the Sun or creating through their propagation with their response in the Earth environment is complicated and thus it is a subject of intensive research for more than four decades. We believe that we know basic mechanisms of mentioned interactions. Our department deals with different aspects of this interaction and collaborates with leading institutions involved in space physics over the world. We offer experimental studies in following closely related directions: (1) the propagation and evolution of solar wind structures through the interplanetary space, (2) modification of their parameters due to interaction each with other and with magnetospheric boundaries, (3) formation of magnetospheric boundaries and transfer of the energy and mass to the magnetosphere via the magnetosheath. The study envisages both systematic analyses of data from various spacecraft operating in the solar wind and around the Earth and case studies of specific events. The solution of the thesis involves the use of present methods of data processing, including machine learning.
Supervisor: Prof. RNDr. František Němec, Ph.D.
Mars, unlike Earth, lacks a global magnetic field that would shield it from the direct influence of the solar wind. Instead, the solar wind induces currents in the ionosphere, forming what is known as an induced magnetosphere. A magnetic pile-up boundary can be identified, along with a bow shock farther upstream due to the supersonic nature of the solar wind. The interaction is further complicated by the presence of remnant crustal magnetic fields, which locally influence the interaction and the ionospheric conditions. As a result, Mars exhibits a highly variable plasma environment governed by numerous factors, fostering irregularities and wave phenomena.
The aim of the thesis is to use plasma and wave measurements from recent spacecraft missions (Mars Express, MAVEN) to investigate the variability of the Martian ionosphere and its interaction with the solar wind. Particular attention is given to wave phenomena, especially in regions of crustal magnetic fields. The study involves both systematic analyses of all available data and case studies of specific events and their effects on the Martian plasma environment. Modern data processing methods, including the potential use of machine learning algorithms, are envisaged to be employed throughout the thesis.
Supervisor: Prof. RNDr. Ondřej Santolík, Dr.
Nonlinear effects in space plasmas influence generation and propagation of electromagnetic emissions, especially those which are generated with embedded discrete time-frequency structures. Whistler mode chorus is a good example of these waves which are propagating in the Earth's magnetosphere. Chorus and other types of whistler-mode waves can influence the space environment of the Earth by their interactions with particles at different energies.
This PhD thesis work will be mainly focused on analysis of generation and propagation of whistler-mode emissions and their interactions with charged particles, improving thus our fundamental understanding of their behavior and effects.
Supervisor: RNDr. Libor Nouzák, Ph.D.
Interplanetary space is not empty but is filled with the solar wind plasma and small objects of various material of micrometer and sub-micrometer size of different shapes called dust. This dust is mostly the product of cometary debris or the collisional cascade of larger objects (e.g., asteroids, micrometeoroids, or space debris). On the other hand, dusty environments around the moons or ringed planets in the interplanetary space can be also populated by ejecta of micrometeoroid bombardment of moon surfaces (e.g., Moon, Europa, etc.) or by volcanic (Io) or thermal activity of the moons themselves (Enceladus). The physical properties of dust particles can be studied in-situ by using both electric field antennas located on the spacecraft and special dust detectors that are designed for each dust environment separately, thus are rarely present. The electric field antennas are a part of the plasma wave subsystem on each spacecraft and the dust is detected as a transient event (spike) in the electric field data. The dust flux is estimated from the abundance of spikes in the data. The ratio of antenna signals provides information about the flux direction, while the size of the signals brings information about the mass of dust particles present in the flux. This approach has been successfully employed on the Parker Solar Probe and Solar Orbiter spacecraft to measure alpha and beta meteroids in the close vicinity of the Sun as well as to determine interplanetary dust flux variation with radial distance from the Sun and solar cycle. We suppose to employ the same detection method for analysis of the Saturn and its rings at different radial distances from Saturn using the Cassini spacecraft. In this case, we plan to involve data from the CDA (Cosmic Dust Analyser) instrument located on board Cassini with motivation to obtain supplementary information about the dust particles detected by the antenna instruments.
