I will present new results from the first deep ALMA continuum image of the Hubble Ultra Deep Field (HUDF), designed to better connect our UV/optical and FIR/mm views of the high-redshift Universe. From a mosaic of 45 ALMA pointings we have constructed a 1.3mm image covering the full 4.5 sq arcmin of the HUDF as previous imaged with WFC3/IR and ACS on Hubble. This new image reaches an rms depth of 35 micro-Jy at a resolution of of 0.7 arcsec. I will describe the design and implementation of this project, and the analysis of the final data product both for source discovery and stacking in the galaxy mass/redshift plane. After presenting our results I will discuss the implications of our findings for our understanding of the 1.3mm background, the mass dependence of star formation and dust obscuration, and the history of cosmic star-formation density. I will close by discussing the prospects for future progress. [more]
There will be coffee, tea and croissants during the lectures. [more]
There will be coffee, tea and croissants during the lectures. [more]
"Symmetry and orders of magnitude, the two pillars of spectroscopy" [more]
see announcement on black board [more]
The detection of large populations of pebbles of mm-cm sizes in protoplanetary discs around young stars has motivated the study of pebble accretion as a driver of planetary growth. This seminar covers all aspects of planet formation by pebble accretion, from dust growth over planetesimal formation to the accretion of planetary embryos and fully-grown planets with gaseous envelopes. Pebbles are accreted at a very high rate, orders of magnitude higher than accretion of planetesimals, and the rate decreases only slowly with distance from the central star. This allows planetary cores to start their growth in much more distant positions than their final orbits. The giant planets orbiting our Sun and other stars, including systems of exoplanets in very wide orbits, can therefore be formed in complete consistency with planetary migration. I will demonstrate tracks of planetary mass versus semi-major axis for all the major classes of planets and outline priorities for future research directions in planet formation. [more]
Please safe the date! A detailed program will be announced later. But as usual we are going to have talks from all Cluster research areas, i.e. astronomy, cosmology, astroparticle, particle and nuclear physics. Prizes for the two Universe PhD Awards 2016 will be given. In addition, there will be a General Assembly of all Cluster members on Wed., 7 Dec, including elections for Research Area Leaders and Cluster Coordinators.Everybody is welcome. There will be no registration, no fee. [more]
Mixing in the radiative zones of stars is one of the least well understoodcomponents of stellar evolution, and yet can, in many instances, play acrucial role. In recent years, however, much progress has been made inquantifying mixing by a variety of hydrodynamic instabilities, thanks tonumerical experiments that have strongly benefited from advances insupercomputing. I will review the state of the field, and presentperspectives on what can and should be done next by the stellar evolutioncommunity, and by the astrophysical fluid dynamics community. [more]
ALMA has been producing stunning images and results for stars acrossthe mass and evolutionary ranges. In this talk, I will focus on someresults for Asymptotic Giant Branch Stars (AGB), Planetary Nebulae, RedSupergiants (RSG) and Supernovae. An area of particular interest is theshaping process by which AGB stars evolve to form often highly axisymmetricPlanetary Nebulae - what are the roles of binarity and magnetic fields? Aswell as the mechanisms by which some of the stars are losing large amountsof mass (10-7 to 10-4 Msun/yr) to the interstellar medium. Finally I willdiscuss how ALMA long baseline and high frequency data are starting tohelp answer some of the long-standing questions in stellar evolution. [more]
Cosmological Weak LensingWeak gravitational lensing is a unique technique to map the distribution of dark matter in the universe. It is also a sensitive probe of large scale structures in the universe and cosmological parameters. I will first briefly describe the principles of weak lensing. I will then review the current observational status of this field, highlighting several new measurements especially from the ongoing Dark Energy Survey (DES). I will then discuss the status of tensions between cosmological probes and results for a new integrated approach to combine them. [more]
http://wwwmpa.mpa-garching.mpg.de/~komatsu/lectureseries/ [more]
The study of Gravitational Waves (GW) from Core-Collapse Supernova (CCSNe) can help elucidate the explosion mechanism and give us information about the physical properties of the collapsed core.Given the variety of possible GW morphologies (usually long and broadband), the reconstruction of the waveform and extraction of physical information is a difficult task. It requires an understanding of multi-dimensional CCSN simulations, data analysis caveats, detector response, as well as understanding how insights provided by neutrino and electromagnetic messengers help us extract GW signals from the detector noise.In the LIGO/Virgo Supernova Working Group we need all the aspects of this research program.In this talk I will review the techniques used to search for GW from CCSNeand current work on O3 preparation and detection perspectives with possible future GW Observatories. [more]