Projects and Collaborations
The interest and work of our group divides into two broad science areas: the evolution of galaxies, and the observation of galaxy clusters through the Sunyaev-Zel'dovich (SZ) effect. Furthermore, we support the ALMA operations and its users through our ALMA Regional Center (ARC) node at Bonn/Cologne, we operate (with partners) the NANTEN2 submillimeter telescope in Chile, and we participate in the construction of the CCAT-prime submillimeter telescope.
Please click on the menu items to find more details.
CCAT-prime / FYST
The centerpiece of the Cerro Chajnantor Atacama Telescope (CCAT) Observatory is the Fred Young Submillimeter Telescope (FYST), a 6-meter telescope designed for observations at submillimeter to millimeter wavelengths. Located at an exceptional 5,600-meter site on Cerro Chajnantor in the Chilean Atacama Desert, it overlooks the ALMA array. FYST’s innovative optical design enables high-throughput, wide-field observations, allowing for rapid and efficient sky mapping. Its precision surface and superb location provide routine access to the 350-micron observing window.
Designed and built by CPI Vertex Antennentechnik GmbH, FYST is currently being transported from its construction site in Germany to Chile. First light is expected in late 2025.
The University of Bonn is a partner in the CCAT Collaboration which is responsible for construction of the telescope, instrument development, observatory operations, data analysis, and scientific publications. The Millimeter/Sub-Millimeter Astronomy Team at the Argelander-Institut für Astronomie supports both the scientific and technical aspects of the project.
For more details, visit the CCAT Observatory website.
SZ Effect and Cosmology
Our research is centered on the study of the Sunyaev-Zeldovich (SZ) effect from galaxy clusters, which is a tiny modification of the intensity of the cosmic microwave background (CMB) radiation, caused by inverse Compton scattering off the energetic electrons in the intracluster plasma. The SZ effect is a powerful tool in the study of galaxy cluster astrophysics and cosmology, providing information on topics as divers as the accelerated expansion of the universe and cosmic ray composition within AGN jets.
For over one decade we have been involved in the APEX-SZ cluster survey, using one of the world's first multi-pixel TES bolometer cameras, mounted on the APEX telescope in Chile. The data products from APEX-SZ are still being analyzed, while our research has moved onto multi-wavelength follow-up of galaxy clusters, particularly in X-rays and at radio wavelengths. Another focus of our SZ research had been the analysis of all-sky data from the Planck satellite, which we are using to gain expertise on SZ spectral measurements and prepare for future multi-wavelength CMB/SZ surveys.
At the moment, much of our scientific activities are centered on the CCAT-prime telescope, which will undertake one of the most sensitive and most wide-spectrum surveys of galaxy clusters. This survey will start collecting data as early as 2021, and our team in Bonn is heavily involved in all the relevant aspects of scientific and instrumental planning. The list of Bachelor's/Master's and PhD thesis topics on the right will give some idea on the breadth of our research.
To get a more general understanding of the many different aspects of the SZ effect and their impact on cosmological research, please have a look at the two recent documents listed below. One was prepared for the Astro 2020 Decadal Survey in the US, the other was prepared for the ESA Voyage 2050 call for their long-term scientific planning.
"SZ spectroscopy" in the coming decade: Galaxy cluster cosmology and astrophysics in the submillimeter (arXiv:1903.04944)
A Space Mission to Map the Entire Observable Universe using the CMB as a Backlight (arXiv:1909.01592)
For any question regarding SZ science, its future prospects, or the research opportunities in this group, please contact Dr. Kaustuv Basu or write him an Email (contact).
Galaxy Evolution
More information here. This page is under construction.
ALMA
More information here. This page is under construction.
NANTEN2
More information here. This page is under construction.