The COSMOS Legacy Survey: We are members of the COSMOS Legacy, a global collaboration built around an HST Treasury Program of ACS images covering an unprecedentedly large 2square-degree field with extensive follow-up observations, over a broad range of wavelengths, using forefront facilities around the world. The primary goal of the COSMOS program is to establish the links between the evolution of galaxies and their central black holes, their environments and the large-scale structure in which they are embedded. With COSMOS, we are taking the systematic study of galactic environments out to high redshifts, up to z~2.5-3, thus reaching to the peak period of star-formation and AGN activity in the Universe. The size of the COSMOS ACS field is chosen so that the transverse dimension exceeds 50 comoving Mpc at all redshifts z > 0.5, thus comfortably exceeding the largest known structures in the Universe, minimizing cosmic variance and ensuring that the full range of cosmic environments is sampled. The worldwide COSMOS team is assembling a set of very deep multi-wavelength data on this field, including deep ground-based imaging in the optical and near-infrared, in the radio, and with X-ray and ultraviolet satellites.

zCOSMOS, 40'000 Spectroscopic Redshifts (and more!) for COSMOS: We are leading zCOSMOS (PI: Lilly), the approved Large Program of 600 hours on the ESO VLT to acquire spectra and redshifts of approximately 40,000 0 < z < 3 galaxies in the COSMOS survey field. The primary goals of zCOSMOS are to characterise the environments of galaxies from the immediate group scale up to the 100 Mpc scale of the cosmic web, and thus to understand the interplay between the evolution of galaxies and AGN and their cosmic environments.

ULTRA-VISTA: UltraVista is a spin-off of COSMOS. It is an ESO public survey of the COSMOS field with the NIR VISTA facility, which will soon commence and will be unmatched in depth and area until the launch of the JWST mission. ULTRA-VISTA will amount to 1400 hr of ultra-deep, and ~200 hr of wider, less deep, broad-band imaging in the Y, J , H, and Ks filters. A main goal of the survey is to further our understanding of the very high redshift universe (z > 6.5). In addition however, ULTRA-VISTA will make it possible to secure a large, volume-complete, census of stellar populations out to z~4. The survey will reach down to 0.1L*; the total volume between z = 2 and z = 4 will be 1.6 x 10^7 Mpc^3, thereby providing a representative sample of the universe, minimizing cosmic variance.We at the ETH are committed to contribute to the quality control of the ULTRA-VISTA data emerging from the pipeline processing software developed by the Consortium, and will be amongst the few European Institutes that will have first-hand access to the ULTRA-VISTA science data produced within the Consortium. ULTRA-VISTA will allow for a selection of 2<5 galaxy samples by stellar mass down to M~10^10 solar masses.

ZENS: The Zurich ENvironmental Survey: ZENS is a deep optical imaging survey of a complete sample of 185 groups between 0.05 < z < 0.06 identified from the 2dFGRS. The optical ZEN Survey has a complement at radio wavelengths: The ZENS groups have been observed at the GBT to determine their HI content down to faint limits (PI: J. vanGorkom, Columbia University). The ZENS groups cover a large range of mass, density, velocity dispersion, compactness and location relative to the large-scale structure, so we will learn how the galaxy properties depend on group properties and large-scale environment. This is key to constraining models and theories of galaxy formation - to understand the processes that shape the Hubble sequence and the origin of the morphology-density relation. This dataset provides the z=0 baseline to compare the results on the Group environment at z=1 that zCOSMOS will deliver.

Searches for the earliest galaxies: We will receive the first data on the early Universe that will be taken with the new camera to be installed on the Hubble Space Telescope - the UV-to-NIR WFC3 camera. We will have priviledged access to the Early Release Science (ERS) data (through membership in the Science Oversight Committee for the WFC3), which include 40 orbits of NIR imaging of the GOODS field, and, as members of the UDF09 international collaboration, to the UDF09 data as well. The UDF09 is a spin-off of our UDF05 project, based on an HST Large Program of 204 orbits (GO-10632; Cycle 14). The UDF05 constructed so as to increase the depth and area coverage of the Hubble Ultra Deep Field (HUDF), and consists of four fields with very deep ACS and NICMOS imaging. We at the ETH have already used the UDF05 to pin down the faint end slope of the Luminosity Function of star forming galaxies at redshift 5 and 7; ongoing projects include quantifying the physical properties of galaxies at these epochs. The UDF09 program of WFC3 imaging (GO-11563; Cycle 17) has been granted 192 orbits for infrared imaging of the HUDF/UDF05 fields to increase of an order of magnitude the sample of z~7 galaxies, to detect about a couple of dozens z~8-9 galaxies, and possibly to glimpse at the z~10 universe as well. The ERS data and the UDF09 data will start flowing in as soon as the WFC3 will become operational after the next Servicing Mission to the Hubble, which is now planned for the early Spring 2009.

Magnetic fields at high redshifts: We are probing magnetic fields at in the high redshifts intergalactic medium. Using a large sample of Faraday Rotation Measures from QSOs extending up to z~3 we are studying magnetic fields at high redshifts. We have recently found that the width of the RM distribution increases with redshift and hypothesized that this is caused by the increasing probability with z of intercepting an intervening system. More recently we could test this hypothesis directly using UVES/VLT spectra. We have found that lines of sight with intervening MgII absorption systems have significantly higher Faraday Rotation than those without. Our findings imply that normal galaxies at z approx. 1 had already a magnetic field of B approx 10 μG comparable to those in today’s spiral galaxies. This result has been published in Nature. We are now doing the follow-up imaging of the QSO fields to identify the parent galaxies responsible for the MgII absorption. We can then relate the observed RM values with the impact parameters and can thus study the extension of the magnetic fields and how they are related with other galactic properties, e.g. luminosity and color.

Planet-Z: PLANET-Z is a multi-disciplinary research effort in Planetary Sciences linking research groups at the ETH Zurich, the University of Zurich and the University of Bern. The initial focus is on planet formation, from circumstellar disks, through numerical dynamical simulations of disks to the collisions of large planetesimals and the creation of planetary interiors.

Precursor Science for MUSE: MUSE is a second-generation instrument for the VLT, being built by a European consortium of which ETH is a member. MUSE will be an integral field spectrometer with a 1x1 arcmin^2 field of view sampled at 0.2x0.2 arcsec^2 spaxels (90,000 channels), spanning the 4800-9600 A wavelength range at R ~ 3000, which will be fed by the new ESO AO facility. MUSE will go to the telescope in 2010/11 and will have a GTO program of more than 200 nights on the VLT. In anticipation of the forecoming MUSE data, we are building up a MUSE team at ETH to develop the science program for the MUSE GTO time.

EUCLID, Exploring Dark Energy: EUCLID is a candidate ESA Cosmic Visions mission to study fundamental cosmology through weak lensing, BAO and other cosmological probes. The current concept is based around a 20,000 deg^2 imaging survey at 0.2 arcsec resolution in the visible, and at poorer resolution for photometry (to H_AB = 24) in the near infrared; a 10^8 galaxy redshift survey over the same region, plus roughly 2 mag deeper imaging and spectroscopy in a smaller deep survey region. ETH is a member of the consortium (ex-DUNE) that is studying the combined visible and infrared channel.

Galaxy Formation within the Cosmic Web: We are pursuing a strong program of numerical experiments at the ETH Physics Department Beowulf Cluster BRUTUS and at the National Swiss Supercomputing Center (CSCS) to address a number of fundamental questions concerning the formation and evolution of galaxies and structure in the universe, including:

• A few million CPU hours program to study the evolution of central massive galaxies - and satellite galaxies - in the potentials of galaxy groups;

• A similar large program to investigate flows and galaxy alignments with the filaments of the cosmic web;

• The formation of a large spiral galaxy across a range of scales, from the Milky Way down to the LMC. Work in progress is also looking at the satellites of the Local Group and and at the effect of early heating from a UV field produced by Pop III stars;

• The orbital evolution and the mass growth of central galactic black holes during mergers with a resolution of 1 pc in a box of hundreds of kpc. These unprecedented simulations include molecular gas, metals and radiative feedback.

Ly-alpha fluorescence: Using hydrodynamical simulations of structure formation and a radiative transfer scheme, we have developed a method to produce realistic simulations of fluorescent Ly-alpha sources at high redshift. We are now applying our method in different observational contexts, aimed at detecting the filamentary cosmic web. Our studies of the IGM will also be based on looking at the three-dimensional distribution of neutral hydrogen in the zCOSMOS 100x100x1000 Mpc^3 volume at z~2-2.8, in order to understand the relationship between gas and galaxies at high redshifts.

ZEBRA2 - Beyond ZEBRA: Building on ZEBRA, our state-of-the-art package for photometric redshift estimates, we are building ZEBRA2, a software package to determine the full statistical distributions of several key diagnostics of galaxy evolution (including stellar masses, metallicities, etc). ZEBRA2 uses a novel template-mismatch minimization algorithm, which is an expansion of the one we used in ZEBRA.

Computational Astrophysics Program: Within the framework of Adaptive Mesh Refinement, we are:

Developing numerical techniques (a) for the study of systems characterized by stiff sources, such as astrophysical fluids with efficient radiative losses or stiffly coupled multi-fluid models; and (b) to account for the effects of cosmic-ray on hydrodynamics;

• Implementing a magneto-hydrodynamic code for cosmological simulations;

• Using our large scale structure simulations which include matter and magnetic field distributions to study the origin and propagation of ultra high energy cosmic rays.

Primordial non-Gaussianity and the 21cm background: We are studying the potentiality of 21cm studies to constrain the level of non-Gaussianity in the primordial density field. In this context, we are also using state-of-the-art N-body simulations with non-Gaussian initial conditions, run at the Swiss National Supercomputing Center, to determine the evolution and properties of the Universe with non-Gaussian initial conditions - to forecast the ability of upcoming experiments to constrain the degree of primordial non-Gaussianity, using the abundance and clustering of galaxy groups and clusters.

Dusty Circumstellar Disks and Planet Formation: Using cutting-edge numerical simulations we are pushing a vigorous program in planet formation with specifically the following aims:

• To study the formation of protoplanetary disks from the collapse of a rotating molecular cloud core with sub AU resolution. We are working on including a turbulent velocity field in the initial conditions;
• To investigate how the migration rate changes with more relistic equations of state. Our SPH simulations include radiative transfer and planets with time-dependent mass. We use the splitting of SPH particles to follow the flow around the planet with unprecented resolution, and study the structure of the circumplenetary envelope where satellites of giant planets might form. We furthermore feed the temperatures and densities obtained in our SPH simulations into a chemical network, to get insight into the chemical evolution of a protoplanetary disk, and be able to interpret the observations.
• To study the effect of a spiral wave - due to a gravitational instability or an embedded planet - on the local chemistry in a protoplanetary disk and the potential feedback on the dynamics.

Wengen Code Comparison We are coordinating a large project in computational astrophysics that involves the comparison between SPH and grid codes (including AMR codes) on a variety of test problems that are of interest to cosmology, physics of the interstellar medium, star and planet formation. Codes participating to the project include GASOLINE, ENZO, FLASH, GADGET2 and HYDRA.