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ASTRONET ERTRC Report Radio Astronomy in Europe: Up to, and beyond, 2025 A report by ASTRONET’s European Radio Telescope Review Committee ! 1!! ! ! ! ERTRC report: Final version – June 2015 ! ! ! ! ! ! 2!! ! ! ! Table of Contents List%of%figures%...................................................................................................................................................%7! List%of%tables%....................................................................................................................................................%8! Chapter%1:%Executive%Summary%...............................................................................................................%10! Chapter%2:%Introduction%.............................................................................................................................%13! 2.1%–%Background%and%method%............................................................................................................%13! 2.2%–%New%horizons%in%radio%astronomy%...........................................................................................%13! 2.3%–%Approach%and%mode%of%operation%...........................................................................................%14! 2.4%–%Organization%of%this%report%........................................................................................................%15! Chapter%3:%Review%of%major%European%radio%telescopes%................................................................%16! 3.1%–%Introduction%...................................................................................................................................%16! 3.2%–%Regional%interferometers:%eQMERLIN,%WSRT,%and%AMI%....................................................%16! 3.2.1 – e-MERLIN!..............................................................................................................................................................!16! 3.2.2 – WSRT – The Westerbork Synthesis Radio Telescope!..................................................................!18! 3.2.3 – AMI – Arcminute Micro-kelvin Imager!.....................................................................................................!19! 3.2.4 – Major regional interferometers outside Europe: ATCA, JVLA and GMRT!...........................!19! 3.3%–%PanQEuropean%interferometers:%EVN%&%LOFAR%...................................................................%20! 3.3.1 – EVN – European VLBI Network!.................................................................................................................!20! 3.3.2 – LOFAR – Low-Frequency Array!.................................................................................................................!21! 3.3.3 – Other major, non-European facilities: VLBA, MeerKAT and ASKAP!.....................................!23! 3.4%–%Large%single%dishes:%Effelsberg,%Lovell,%Yevpatoria,%Nançay%and%Sardinia%.................%24! 3.4.1 – Effelsberg!...............................................................................................................................................................!24! 3.4.2 – Lovell!........................................................................................................................................................................!25! 3.4.3 – Yevpatoria!..............................................................................................................................................................!25! 3.4.4 – Nançay!....................................................................................................................................................................!26! 3.4.5 – Sardinia!...................................................................................................................................................................!27! 3.4.6 – Other major, non-European facilities: Arecibo, Parkes, GBT and FAST!..............................!27! 3.5%–%MediumQsized%single%dishes:%Medicina,%Noto,%Metsähovi,%Onsala,%Toruń%and%Yebes %.......................................................................................................................................................................%28! 3.5.1 – Medicina and Noto!............................................................................................................................................!28! 3.5.2 – Metsähovi!...............................................................................................................................................................!29! 3.5.3 – Onsala!......................................................................................................................................................................!29! 3.5.4 – Toruń!........................................................................................................................................................................!30! 3.5.5 – Yebes!.......................................................................................................................................................................!31! 3.5.6.!–!Other!medium7sized!facilities!........................................................................................................................!31! 3.6%–%Conclusions%.....................................................................................................................................%31! A.1%–%Graphical%comparison%of%telescope%parameters%................................................................%32! Chapter%4:%Addressing%the%ASTRONET%Science%Vision%goals%with%existing%European%radio% telescopes%.......................................................................................................................................................%40! 4.1%–%Introduction%...................................................................................................................................%40! 4.2%–%Contributions%of%radio%astronomy%to%the%ASTRONET%Science%Vision%..........................%40! A.%Do%we%understand%the%extremes%of%the%Universe?%..................................................................%40! A1. How did the Universe begin?!..............................................................................................................................!40! A2. What is dark matter and energy?!......................................................................................................................!40! A3. Can we observe strong gravity in action?!.....................................................................................................!42! A4. How do supernovae and gamma-ray bursts work?!.................................................................................!42! A5. How do black hole accretion, jets and outflows operate?!....................................................................!43! A6. What do we learn from energetic radiation and particles?!..................................................................!43! B.%How%do%galaxies%form%and%evolve?%...............................................................................................%44! B1. How did the Universe emerge from the Dark Ages?!..............................................................................!44! B2. How did the structure of the cosmic web evolve?!....................................................................................!44! B3. Where are most of the metals throughout cosmic time?!......................................................................!45! B4. How were galaxies assembled?!........................................................................................................................!45! 3!! ! ! ! B5. How did our galaxy form?!.....................................................................................................................................!46! C.%What%is%the%origin%and%evolution%of%stars%and%planets?%.........................................................%47! C1. How do stars form?!..................................................................................................................................................!47! C2. Do we understand stellar structure and evolution?!.................................................................................!47! C3. What is the life cycle of the interstellar medium and stars?!................................................................!48! C4. How do planetary systems form and evolve?!............................................................................................!48! C5. What is the diversity of planetary systems in the Galaxy?!..................................................................!48! C6. Determine the frequency of Earth-like planets and push towards direct imaging.!..................!49! D.%How%do%we%fit%in?%................................................................................................................................%49! D1. What can the Solar System teach us about astrophysical processes?!........................................!49! D2. Develop a unified picture of the Sun and the Heliosphere.!.................................................................!49! D3. What drives solar variability on all scales and transient activity?!....................................................!50! D4. Understand the role of turbulence and magnetic fields in the evolution of the primordial nebula!.......................................................................................................................................................................................!50!
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