splinter meeting of the conference Zooming in: The Cosmos at High Resolution
Bonn, Germany, Sep. 14-15, 2010
Conveners: Dominik Bomans, Adam Ruzicka
Meeting schedule now available - UPDATED (Aug 27)!
The usual one to two year rate at which the Magellanic meetings have been organized turned out to be ideal in order to cover the steeply increasing wealth of observational and theoretical data related to the Magellanic Clouds. Therefore, the year 2010 is a natural window for organizing the next workshop on the Magellanic System. It is highly desirable to allow for a meeting of the scientists involved in the research of the Magellanic Clouds in order to summarize the recent achievements, to exchange knowledge, to encourage collaborations and to summarize the future prospects.
Nearby astrophysical laboratory.The Magellanic Clouds are a unique laboratory to study various astrophysical processes at a great detail, as their heliocentric distances are only 50 kpc (LMC) and 60 kpc (SMC), respectively. Unlike our Galaxy, the Magellanic Clouds are unevolved irregular galaxies and thus the formation of stars or the behavior of the multiphase interstellar medium (ISM) can be studied in a more primitive environment of generally low metallicities (compared to the Galaxy). There is also a strong evidence that the Clouds have been undergoing an interaction involving also the Milky Way. The high resolution observational data on both the global and local kinematics and morphology of the Clouds have enabled several exciting studies on the dynamical evolution and possible origin of the Magellanic Clouds. The knowledge in the history of observed galactic systems might improve or correct the present cosmological models. We have an opportunity to follow the interaction and assembly of galactic structures prominent in the high–redshift Universe.
Observations. An impressive number of high–resolution observations and surveys of ISM and stellar populations have been completed, continued or just started. The team of the microwave telescope NANTEN keeps offering us with detailed mapping surveys of CO in the Magellanic Clouds. The space probe XMM–Newton is being used for a new X–ray survey of the SMC. Radio observations in the emission line of neutral hydrogen continuously improve the insight into the features of the large–scale witnesses of the interaction between the Magellanic Clouds, namely of the Magellanic Stream – a prominent trailing filament of neutral hydrogen emanating from the Magellanic Clouds. The Halpha observations have revealed the evidence for the rather quick decay of the Magellanic Stream, opening the question of feeding this extended structure with gas. The Spitzer Space Telescope has been used to conduct several infrared surveys, e.g. SAGE or S3MC. New projects for stellar photometry have begun or continue, e.g. OGLE. Spectroscopic surveys have also offered remarkable data.
Theoretical studies. More than 40 theoretical studies focusing on the dynamical evolution of the Magellanic Clouds have been carried out so far. The observed large–scale distribution of the gaseous medium associated with the Clouds was explained satisfactorily as an outcome of a long term hydrodynamical and tidal (gravitational) interactions between the LMC, the SMC and the Galaxy. However, in 2006 the spatial motion of the Clouds was determined with an unprecedented accuracy using the astrometric measurements by the HST. The new data introduced a serious challenge to the standard models for the dynamical evolution of the Clouds. As the current spatial velocities increased and the Clouds were put on unbound orbits around the Galaxy, the timescales for the mentioned processes dominating the interaction were reduced dramatically. This complication hasn’t been fully resolved so far.
Hot topics and open question:
- the 3D shape of the main body of the SMC – stars and interstellar medium
- uneven and peaky star formation history in the LMC
- metalicity and star formation differences between the LMC and the SMC
- local and global features of the multi–phase ISM in the Magellanic System
- kinematics and morphology of the Magellanic Stream and its interaction with the ambient hot medium in the Galactic halo
- What is the orbital history of the Magellanic System? Is it bound to the MW? Do the Clouds form a bound system and if so, since when?
- What creates the Magellanic Stream: ram pressure, tidal forces or a combination of both?
- Are best dynamical models in agreement with the star formation history of both clouds? Can we assign major star formation epochs with the orbital properties of the Magellanic System?
- What is the age of the Magellanic Stream and the Leading Arm?
- What constraints on the MW potential, i.e. its flattening, can be derived?
- What is the mass and structure of the Magellanic. Clouds’ DM halo? Do both Clouds share a common DM. halo or do they have individual halos? What is their halos’ mass and shape?