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Projekt Druckansicht

Extragalaktische Archäologie: Das Zusammenspiel von Aktiven Galaxienkernen und Dunklen Materiehaufen im Verlauf der kosmischen Zeit

Antragsteller Dr. Mirko Krumpe
Fachliche Zuordnung Astrophysik und Astronomie
Förderung Förderung von 2014 bis 2018
Projektkennung Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 265092751
 
Erstellungsjahr 2019

Zusammenfassung der Projektergebnisse

The research project aimed for providing the evolution of the full distribution of the number of AGN as a function of halo mass in the last ∼11 Gyr with three independent measurements. In addition, the observed AGN clustering properties and halo occupation distribution should be compared to cosmological simulation to discriminate between currently favored AGN triggering scenarios. As found previously at other redshifts, our HOD model for local and z ∼ 0.6 type I AGN indicates that above DMH masses of Mh ∼ 1012 h−1 M⊙ the duty cycle of AGN in satellite galaxies decreases with increasing halo mass, in that the slope of the HOD is shallower for AGN than for galaxies. This trend tends to weaken with redshift, i.e., the discrepancy between the AGN and galaxy HOD is smaller at higher redshift than in the local Universe. Only in the local sample, we could also compare in an unbiased way the clustering properties between type I and II AGN. Local type II AGN have an HOD that is very similar to that of galaxies. The average number of type II AGN in satellite galaxies increases approximately proportionally to DMH mass, as is observed for galaxies. Thus, the ratio of type I to II AGN should decrease with DMH mass. These differences in the clustering properties of type I and type II AGN are at odds with a simple orientation-based AGN unification scheme. Current state-of-the-art hydrodynamical simulations are able to well reproduce not only the galaxy luminosity function but also the observed HOD of galaxies very well. However, even though the AGN luminosity function is well represented, the distribution in the observed parameter plane (e.g. black hole mass vs. accretion ratio) as well as the AGN clustering properties and the HOD differs significantly from the observed ones. This project shows how much more constraining power is given to these simulation if they do not only have to reproduce luminosity function but clustering and HOD parameter as well. During this project, a student wrote his Diploma thesis on correlation functions and a PhD student was co-supervised on clustering measurements and HOD modeling using cosmological simulations. The time plan for HETDEX slipped significantly. The CCDs did totally not perform as expected and caused a major delay of 3 years. Thus, instead of using the HETDEX data as a third independent AGN clustering and HOD measurement, we used the SDSS CMASS galaxies and ROSAT AGN at z ∼ 0.6 instead. - For different reasons the auto-correlation functions of the 2MASS and CMASS galaxy sample turned out to be significantly more complicated and time-consuming than expected. This could have been not forseen unless digging already very deep into the data.

Projektbezogene Publikationen (Auswahl)

 
 

Zusatzinformationen

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