SpheroidsEvolution · New and Complete Methods to constrain the Evolution of Massive Galaxies and their central Black Holes
FP7 — People (Marie Curie Actions)
- Duration
- 2011-09-01 → 2013-08-31
- EU contribution
- €186,864
- Participants
- 1
- Scheme
- MC-IEF
Lines connect the coordinator with its partners.
Results in brief
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.
Data: CORDIS, © European Union
Project objective
Detailed Semi-Analytic Models (SAMs) of galaxy formation often reach opposite conclusions on how early-type, bulge-dominated galaxies have formed and evolved. Hierarchical models predict a fraction of their stars formed in a fast, high-redshift burst of star formation, and the rest assembled later on via a sequence of (mostly gas-poor and minor) mergers. Monolithic models propose instead that most of the stars were formed in the initial burst. On other grounds, deep observations have now showed that massive spheroids at high redshifts, are much more compact than their local counterparts. Moreover, in recent years, dynamical observations have revealed that Supermassive black holes (BHs) are ubiquitous at the centres of all local early-type galaxies. These observations show that tight correlations exist between the mass of the BH and the bulge and velocity dispersion of the host. Hierarchical models predict that the late assembly of galaxies (and their BHs), can efficiently ``puff-up’’ their sizes, while monolithic models claim that the size evolution is mostly driven by a quasi-adiabatic, slow expansion consequent to strong mass loss caused by quasar and stellar feedback.In this project we propose to shed light on massive galaxy evolution by carrying out an extensive research based on exploiting state-of-the art purely hierarchical and mixed models for galaxy evolution. We will compare the predictions on mass, size, profile, velocity dispersion, and number density evolution of massive galaxies and their connection with central BHs, with a variety of new data sets derived from large and deep surveys of massive galaxies led by our group, such as COSMOS, NGVS and the local SDSS. We will also make use of detailed numerical simulations performed by our group, that will allow us to set definite answers on some theoretical predictions such as the expansion of galaxies.
Original text from CORDIS.
Participants
- OBSERVATOIRE DE PARIS · ParisCoordinatorFrance
Links
Data: CORDIS, © European Union