Mission
Astroserver is a private, community supported non-profit organization with affordable solutions in research astronomy. The team offers expertise mainly in stellar astrophysics, spectroscopy, non-LTE model atmosphere calculations, assistance with publications and media content production, and help with service observations. These services are similar to the tasks of post-doctoral and graduate researchers. Therefore, our activity can be integrated into the programme of graduate schools and research institutes. To wrap-up: Astroserver is your "occasional post-doc".
The main goal of the Astroserver Team is to provide precise and reliable measurements of stellar atmospheric parameters in a consistent way across the Hertzsprung-Russell Diagram and make it accessible to everyone. The accuracy of these solutions depends on the choice of the model, the quality of input atomic data and observations. Therefore, our Team continuously improves the models and revise the atomic data input by analyzing high quality observations of standard objects. Beyond the main mission the Team is also keen on finding solutions to challenging problems on the frontiers of applied stellar spectroscopy.
Interested researchers: Please consider our services in the budget plan of your grant applications! Upon request we contribute to such proposals free of charge.
Feel free to contact us for more information!
- 2023
An 18.9-minute Blue Large-Amplitude Pulsator Crossing the "Hertzsprung Gap" of Hot Subdwarfs
Blue large-amplitude pulsators (BLAPs) represent a new and rare class of hot pulsating stars with unusually large amplitudes and short periods. Up to now, only 24 confirmed BLAPs have been identified from more than one billion monitored stars, including a group with pulsation period longer than 20 min ...
- 2017
Atomic diffusion in the atmosphere of Feige 86
A re-analysis of the ultraviolet and optical spectra of Feige 86 found large abundances of xenon in its atmosphere. The star shows a rich, sharp-lined peculiar spectrum both in the ultraviolet and the optical, which marks active atomic diffusion processes.
- 2023
Unveiling the Evolutionary State of Three B Supergiant Stars: PU Gem, ϵ CMa, and η CMa
We aim to combine asteroseismology, spectroscopy, and evolutionary models to establish a comprehensive picture of the evolution of Galactic blue supergiant stars (BSG). To start such an investigation, we selected three BSG candidates for our analysis: HD 42087 (PU Gem), HD 52089 (ϵ CMa), and HD 58350 (η CMa). These stars show pulsations and were suspected to be in an evolutionary stage either preceding or succeding the red supergiant (RSG) stage.
- 2017
A FEROS survey of hot subdwarf stars
We have initiated a small survey of twenty hot subdwarfs using the Fiber-fed Extended Range Optical Spectrograph (FEROS) and the 2.2-m telescope at La Silla. The sample includes apparently single objects as well as hot subdwarfs paired with a bright, unresolved companion extracted from our GALEX catalogue of hot subdwarf stars (Vennes et al., 2011; Nemeth et al., 2012). As expected (Kawka et al., 2015; Kupfer et al., 2015), the fraction of radial velocity variables ...
