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New and Complete Methods to constrain the Evolution of Massive Galaxies and their central Black Holes

Final Report Summary - SPHEROIDSEVOLUTION (New and Complete Methods to constrain the Evolution of Massive Galaxies and their central Black Holes)

Project SpheroidsEvolution (274139)

New and Complete Methods to constrain the Evolution of Massive Galaxies and their central Black Holes

Final report

In this second year of work we have completed several of the steps detailed in our application. Details on the scientific achievement are detailed in the following list:

1. Francesco Shankar has refined the semi-empirical model for galaxy evolution (SHAM) built on top of numerical dark matter merger trees. Details of the code have been provided in the Application and in the mid-term report, but for convenience are briefly reviewed here. Along the main branch the central galaxy is initialized via empirical correlations, and morphologically progressively transformed from disc to bulge/spheroid via minor and major mergers, as well as disc instabilities. Similarly, all infalling satellites on the main branch are initialized via empirical correlations and assigned a dynamical friction timescale. One paper has been submitted on results obtained with this model: Shankar, Mei et al., submitted. This paper shows for the first time how environment can efficiently break degeneracies among different galaxy evolution models.

2. The SHAM model has been used to study on one side environmental dependence, and on the other side the role of progenitor bias in determining the global size evolution of early-type galaxies. A separate paper is in preparation.

3. A Halo Occupation Distribution (HOD) model that assigns central and satellite galaxies to dark matter haloes in a given simulation has been developed. The HOD technique is extremely useful and complementary to full galaxy models, as it empirically probes the spatial location of galaxies inside and outside dark matter haloes. A technical paper led by the Fellow is in preparation. The latter work will serve as a base to create the mock catalogs for the preparation phase of the European mission EUCLID.

4. Regarding the other important goal of the Marie Curie project, i.e. the co-evolution of BHs and galaxies, the Fellow has further refined the continuity equation codes started before the beginning of the Marie Curie, to insert predictions of small and large scale structure of active galaxies at all redshifts and luminosities.
A paper on this project is underway, and will be submitted by the end of 2013-beginning of 2014. Other achievements in this respect have been a clear advance in the determination of the local BH mass function, an invited review for Classical and Quantum Gravity (submitted), and a refinement of the QSO merger model. All these papers are included in the lists below.

5. A variety of additional projects have been started by the Fellow during this second year with different collaborators, and all focused on the project of the Marie Curie grant. These projects will still serve as a base for future publications in the years 2014-2015.

The support of the European grant will anyway be acknowledged in all the publications where the support of the Marie Curie grant has been relevant.

The main projects are (not given in any publication list below):

• study of the bolometric luminosity function of active galaxies;

• obscured fraction of active galaxies;

• study of the colour and velocity functions of massive, early-type galaxies coupled to their size evolution;

• general predictions of alternative models for the size evolution of early-type galaxies using expansion and shut-down models.

It is relevant to point out that thanks to the visibility offered by the Marie Curie grant, the Fellow was able to step in a number of shortlists for faculty jobs in Europe. In June 2013, he has been offered a permanent Lectureship at the University of Southampton, UK.

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