Former research groups of the Konkoly Thege Miklós Astronomical Institute

Lendület Fly’s Eye Research Group (2012-2019)
Lendület Légyszem-kamera Csoport
András Pál

CoRoT Hungarian Astroseismological Research Group (2012-2015) - Dr. Paparó Margit
Group Leader: Paparó Margit
Group Members: Markus Hareter (AT), Benkő József, Bognár Zsófia
About the research team:The team was established in 2005 to support the preparatory work of the CoRoT (Convection, Rotation and Planetary Transits) space project in the framework of the PECS. To date, our task is to collect additional multi-colour photometric measurements, which make excellent use of the Hungarian instrumental capabilities, and to process the semi-annual continuous data series of CoRoT. The importance of this research area is due to the fact that we do not have direct access to the layers below the stellar photosphere. Astroseismology is the only way to study the inner layers of stars, where the discontinuity of the energy flow excites self-sustained oscillations that propagate as waves. The oscillations form brighter and darker (higher and lower temperature) regions on the surface of the star, creating characteristic patterns. The waves of different frequencies penetrate to different depths inside the star and are then reflected back. The difference between the frequencies gives the parameters (pressure, density, temperature, sound speed and chemical composition) of the region where only one wave passes. The more pulsational modes and more precise frequencies can be determined from the observations and the more vibrations that can be identified (radial, horizontal, azimuthal quantum numbers), the more detailed the picture of the internal structure of the star will be. Since the CoRoT space telescope does not measure in calibrated wavelength ranges, ground-based multi-colour photometry measurements are important for the identification of the type of the large number of stars studied and for the identification of the vibrations.Depending on the scientific profile of the current members of the team, different types of stars with characteristic vibrations will be studied. We are still working on RR Lyrae stars with Blazhko modulation (radial pulsation), but in the future the bulk of our investigations will be on Delta Scuti (pressure oscillations) and Gamma Doradus (gravitational oscillations). The presence of multiple frequencies in these non-radially pulsating stars will lead us to the level of astroseismology. New methods are sought to identify these vibrations using regularities between a large number of frequencies. We are using the new frequency modulation (FM) method to detect binary systems, determine orbital parameters, relative mass and radial velocity.Since stars are the fundamental building blocks of the Universe and exoplanets orbit stars, other fields cannot flourish without a better understanding of stellar physics. The group is supported by ESA's PECS project through the Hungarian Space Agency. We currently have a contract until the end of 2013, with a decision on its continuation to be taken this year. The amount available in 2013 is 30 000 EUR. 15 000 EUR can be drawn down at the beginning of 2014 after the last milestone has been reached

Hompage of the group

Gaia Research Group (2012-2015) - Dr. Szabados László
Group Leader: Dr. Szabados László
Group Members: Klagyivik Péter, Marschalkó Gábor,
Description of the research team: The Specific Object Studies working group of the Gaia DPAC Coordination Unit 7 (CU7) focuses on the study of the observable behaviour of pulsating variable stars, in particular in the field of Cepheid variable stars, and the related simulations. In the framework of the Supplementary Observations working group, photometric observations with the telescopes of the Piskéstető Observatory will be carried out. The observations are partly coordinated with the Ground-Based Observations for Gaia (GBOG) group. In 2010 we joined the Gaia Follow-up Network (FUN) collaboration and the Gaia Science Alerts working group.

Hompage of the group

Konkoly Blazhko Survey Research Group (2012-2015) - Dr. Jurcsik Johanna
Group Leader: Dr. Jurcsik Johanna
Group Members: Szeidl Béla, Sódor Ádám, Smitola Péter
The main research topics of the research group are: Period doubling and additional frequencies in KBS [V759 Cyg (2011); CZ Lac (2010)] and Kepler Blazhko star data.
IPM analysis of multicolor photometric data of Balzhko stars.
Fine tuning of IPM based on photometric/spectroscopic measurements of M3 variables.
Verification of IPM based on photometric/spectroscopic measurements of DR And.
Investigation of M15 variables based on archival photographic and CCD data.
calibration of the [Fe/H](Fourier parameters) formula for spherical sets.
Investigation of modulations of overtone pulsators.
A study of the red giant stars of M3 based on CCD measurements in 2011.
A study of the long secondary periods of red giants compared to the behaviour of Blazhko stars. Calibration of light curve - physical parameter formulas for ugriz filters.

Hompage of the group

Lendület Exoplanets and Stellar Structure Research Group (2012-2015) - Dr. Kiss László
Group Leader: Dr. Kiss László
Group Members: Bányai Evelin, Benkő József, Derekas Aliz, Kővári Zsolt, Mező György, Nuspl János, Regály Zsolt, Sárneczky Krisztián, Simon Attila, Szabó M. Gyula, Szabó Róbert, Vida Krisztián.
Research topics of the research group: Keywords:
- study of eclipsing exoplanets with national and foreign telescopes and space telescope measurements, and theories of planetary formation;
- stellar astrophysics research with the Kepler space telescope and ground-based spectroscopy campaigns;
- small celestial bodies in solar systems;
- instrument development at the Piskéstető Observatory;
the domestic introduction of high-resolution optical spectroscopy

Hompage of the group

Lendület Disk Research Group (2012-2015) - Kóspál Ágnes
Group Leader: Ágnes Kóspál
Group Members: Attila Moór, Zsolt Ragály, Péter Ábrahám
Brief description of the research topic:The formation of the Sun and stars like it, and their planetary systems, is one of the oldest questions of mankind. Today, it is one of the most intensively researched and exciting areas of modern astrophysics. To answer this question, a detailed study of the structure and evolution of orbiting discs is essential. The research team aims to understand the physics of these disks and the dynamical and transport processes that take place inside them. In the framework of this project, we are seeking answers to the following questions. What are the implications for planetary evolution of the dynamical structures observed in the small- and large-scale structures of the disk? On what timescale does the dust and gas material of the disk disappear? Our observations will include the use of the Chilean ALMA submillimetre antenna network. ALMA will be as powerful an instrument for astronomy as the Hubble Space Telescope was a quarter of a century ago. In collaboration with the Numerical Astrophysics Research Group, we will develop the modelling tools needed to interpret the results, opening up a new direction for disc science.

Solar Physics Research Group (2012-2015) - Dr. Robertus von Fay-Siebenburgen
Group Leader: Dr. Ludmány András
Group Members: Baranyi Tünde (PhD), Győri Lajos (PhD), Muraközy Judit, Korsós Marianna Brigitta, Gyenge Norbert, Erdélyi Róbert
A brief description of research topics:A művelt témák leírása:

  • Sunspot databases - our priority, based on a lot of very positive feedback from this research field. This is what our detection material and our evaluation methodology oblige us to do. Our materials are unrivalled and are the most detailed sunspot catalogues available. Part of the work involves cross-calibration analysis of our data with data from other observatories. Further development of the evaluation procedure is also underway, and the method is now at the stage where it can identify and track spot movements and changes on successive observations.
  • Investigating long-term changes in solar activity - one of the most important uses of our sunspot data, has been one of the biggest challenges in solar physics in recent years, as the 24th cycle has been late and low intensity and there is a strong possibility that a prolonged ("Maunder") minimum may occur again in the not too distant future. Our most recent work is on phase differences and solar cycle forecasting in hemispheric cycles.
  • Non-axisymmetric solar activity - A new topic, one of the tasks undertaken in the FP7 project eHEROES. We seem to have found the time-length diagram equivalent of the Spörer (butterfly) diagram describing the time-length variation of solar activity. We have identified a 1.3-year period in the active longitude zone, which was previously detected at the bottom of the convective zone. This may indicate that the active longitudes are rising from the depth of the tachoclinic layer. We further analyse this phenomenon and its correlations with phleractivity.
  • Developing a Fler prediction method - A new topic, one of our tasks in the FP7 project eHEROES. Our method is not based on magnetograms, but on our own sunspot data. We have found features in the behaviour of the horizontal gradient of the magnetic field before a flare that will allow us to estimate the probability of a flare occurring, and even its intensity, over time scales of up to a few hours. Once the method is fully developed, we would like to become a player in the European space weather monitoring system.
  • Modelling irradiances changes - Our detailed and accurate sunspot and flare data allow a more precise study of how these shapes affect the total solar irradiances (TSI) changes. These studies can contribute to our understanding of how the Sun's electromagnetic radiation changes over the long term.
  • Detailed analysis of the evolution of active regions - Previously only possible at daily resolution and for a whole patch group, our data now allow detailed analysis of the internal structure at one and a half hour resolution and polarity separation. A number of new findings on the dynamics of spot group emergence, leader-follower asymmetries, fragmentation have been revealed, which have a significant theoretical literature but lack empirical contributions. In the future, we will conduct a statistical study of patch fragmentation.
  • New activity index - The new demand for long-term data series has also necessitated a revision of the classic sunspot relative index. An international research group was formed, to which we were invited as the other major sunspot data centre besides the Brussels centre for the sunspot relative index. This is our new field of research, our data are suitable to create a more physically based activity index (Debrecen Sunspot Index).

Hompage of the group

Solar and Stellar Activity Research Team (SOLSTART) (2012-2015) - Dr. Oláh Katalin
Group Leader: Dr. Oláh Katalin
Group Members: Bartus János, Forgács-Dajka Emese, Kővári Zsolt, Kriskovics Levente, van Driel-Gesztely Lídia, Vida Krisztián
Research topics of the Research Group - Doppler mapping and differential rotation measurements on young Sun-type stars
-Doppler mapping and measurement of differential rotation on the giant component of RS Cvn-type binaries
-Determining differential rotation from the light curves of rapidly rotating Kepler stars
-The role of binarity in the magnetic dynamo
-Monitoring stellar activity on different time scales from flares to magnetic cycles
-Studying the Sun's magnetic activity at high resolution
-Study of the dynamo of young Sun-type stars in the framework of the solar paradigm
Computational Astrophysics Group (2012-2015) - Regály Zsolt, PhD
Group Leader: Regály Zsolt, PhD
Group Members: Forgácsné Dajka Emese (PhD, 20%), Juhász Attila (PhD, 30%), Király Sándor (MSc, 50%), Kovács Tamás (PhD, 50%), Moór Attila (PhD, 20%), Regály Zsolt (PhD, 75% ), Sándor Zsolt (PhD, 75%), Süli Áron (PhD, 50%), Szabó Róbert (PhD, 20%), Tarczay-Nehéz Dóra (MSc, 60%)
A brief description of research topics:
Numerical methods are used whenever a mathematical model de- scribing an astrophysical system is too complex to be solved analytically. The dynamics of most of the visible matter in the universe can be treated as a compressible fluid. Time-dependent and multidimensional solutions to the fluid equations require numerical methods. A vast range of problems are addressed in this way, from convection in stellar and planetary interiors, the interactions of newborn planets with their protoplanetary dics, to the formation of galaxies and the large scale structure of the universe. Solving the equations of hydrodynamics is a classic problem in numerical analysis which has application to many fields besides astrophysics. Important techniques of computational astrophysics include particle-in-cell (PIC) and the closely related particle-mesh (PM), N-body simulations, Monte Carlo methods, as well as grid- free (with smoothed particle hydrodynamics (SPH) being an important example) and grid-based methods for fluids. In addition, methods from numerical analysis for solving ODEs and PDEs are also used. The main research fields in our group are the following:

  • Modeling planet-disc interactions by means of numerical hydrodynamical simulations using computational demanding GPU-based numerical codes as well as parallelized CPU-based numerical solvers;
  • Studying planet formation theories concentrating on mutual interactions between the planets and the host disc, dynamics of planetesimals, planetary migration of different types;
  • Dust transport and evolution in different models of protoplanetary discs by means of particle and two-fluid approach, formation of planetesimals;
  • Studying stability and chaotic behaviours of planetary systems by means of efficient chaos indicators and high-precision/efficient N-body integrators;
  • High-resoluion infrared spectroscopic observations and modeling of molecular emissions/absorptions of protoplanetary discs by ESO VLT/CRIRES;
  • High angular resolution imaging of protoplanetary discs by radio interferometers (ALMA and MATISEE);

 

Former research groups of the Geographical Institute

 

Former research groups of the Institute for Geological and Geochemical Research