Postdoctoral researcher
Max Planck Institute for Astrophysics
csogeza *;at;* mpa.garching.mpg.de
I am Géza Csörnyei, currently a
Postdoc at Max Planck Institute for Astrophysics.
I am originally from Hungary; I finished both my bachelor's and master's studies at Eötvös University, Budapest. In the meantime, I worked at Konkoly Observatory as an observatory assistant. After finishing my studies, I was admitted to a PhD position at MPA Garching through the International Max Planck Research School (IMPRS). I received my PhD in April of 2024, and will start a Fellowship position at the European Southern Observatory in September 2024!
My research topics are diverse, I have tried out a few fields:
Interested in my research? Here are the ones which I first-authored, with some brief summary! Click on the titles to see more!
Despite being a well-known galaxy, the distance to M 51 was quite uncertain, with little to no agreement between methods. Even though somebody surely observes this beautiful galaxy on the globe every day, and despite it having been visited by the Hubble Space Telescope multiple times, no Cepheid distance was inferred to it—up until now!
Less known than, say, Cepheids, but Type IIP supernovae are also precise distance indicators. Even better, they do not require external empirical calibrations; one may infer distances to them without the need to calibrate a "ladder" to these SNe based on Cepheids or TRGB. One question, of course, is whether these distances are meaningful, and one way to check this is by applying the method to SNe that exploded in the same galaxy.
Another study on the Cepheid period changes; however, this time, instead of a single object, we went after a larger, more representative sample of 148 stars! While we were looking for effects that may be tied to the binarity of the objects, we found something else: that they are not perfect clocks. Not only do they evolve, but they fluctuate as well!
Have you ever wondered how strong emission lines affect the accuracy of photometric redshift estimations? Even though they are pretty random, surprisingly, they improve them noticeably. To show this, we analyzed a large sample of SDSS spectra using machine learning and devised a way to generate spectra with realistic emission line ratios.
This is my very first article. This project dealt with the period changes of a peculiar Type II Cepheid, among the shortest known binary Type II Cepheids. It was known to exhibit strange and strong period changes, so our plan was to investigate how some additional data clarifies the picture drawn 30 years ago.