BIG QUESTIONS IN ASTROPHYSICS – THE NEXT DECADES · ASTROPHYSICS – THE NEXT DECADES. Keynote talks during the symposium will cover major topics in contemporary astrophysics, including

1 BIG QUEST IONS IN ASTROPHYSICS – THE NE X T DECADES

KNUT AND AL ICE WALLENBERG FOUNDAT ION

BIG QUESTIONS IN ASTROPHYSICS – THE NEXT DECADES

A SYMPOSIUM TO CELEBRATE THE KNUT AND ALICE WALLENBERG

FOUNDATION’S 100-YEAR ANNIVERSARY

April 4, 2017, Grand Auditorium, Lux, Helgonavägen 3, Lund



The Knut and Alice Wallenberg Foundation primarily grants funding in the natural sciences, technology and medicine, in the form of grants for basic research of the highest international standard. During the Foundation’s 100 years, SEK 24 billion has been awarded in grants for excellent Swedish research and education. Recent annual grants of SEK 1.7 billion make the Foundation one of the largest private funders of scientific research in Europe.

Over their lifetimes, Knut and Alice Wallenberg built up a sizable fortune, and, even before the establishment of the Foundation, they financed various construction and public development projects. They wanted to organize their support through the establishment of the Foundation.The endowment consisted mainly of shares in Stockholms Enskilda Bank and Investor worth SEK 20 million, SEK 593 million in today’s currency value. Even though the Foundation has granted SEK 24 billion, the assets have, after 100 years and successful capital management, grown to SEK 90 billion.

Knut and Alice Wallenberg were determined to promote scientific research and education beneficial to Sweden, things that contributed to Swedish progress in research and education. In the beginning, the Foundation mainly financed buildings to house research and education. Gradually the support shifted to financing of advanced equipment needed for research. In recent years one of the main areas of support has been individual grants for outstanding researchers. The Foundation supports outstanding individuals through its programs: Wallenberg Scholars and Wallenberg Clinical Scholars for senior scientists; and Wallenberg Academy Fellows for younger scientists. Another important area is grants for researcher-initiated projects with high scientific potential and of the highest international standard.

100 YEARS IN SUPPORT OF EXCELLENT SWEDISH RESEARCH AND EDUCATION



BIG QUESTIONS IN ASTROPHYSICS –

THE NEXT DECADES

To celebrate 100 years of research funding, in 2017 the Knut and Alice Wallenberg Foundation will organize conferences in scientific areas where it has provided substantial support throughout the years. Astronomy is one of these areas. We have been given the honor of organizing a symposium on astronomy in Lund on April 4, 2017. The symposium is titled BIG QUESTIONS IN ASTROPHYSICS – THE NEXT DECADES. Keynote talks during the symposium will cover major topics in contemporary astrophysics, including understanding the formation of planets and stars, galaxy evolution, dark matter and the transient revolution in astrophysics. Other speakers will present their research results from projects that are supported financially by Knut and Alice Wallenberg Foundation. In connection to the symposium, the scientific committee has taken the opportunity to organize three workshops which will cover The Transient Universe and Dark Matter on Monday April 3 and Galaxy Evolution and Star Formation across the Universe on April 5.

The centenary will be celebrated with the following symposia:

Lund, April 4; Lund UniversityUmeå, June 19; Umeå University and Swedish University of Agricultural SciencesLinköping, September 13; Linköping UniversityStockholm, September 15; Stockholm University, KTH Royal Institute of Technology and Karolinska InstitutetUppsala, September 21; Uppsala UniversityGothenburg, September 28; University of Gothenburg and Chalmers University of Technology



08:30–08:35

08:35–08:40

08:40–08:55

08:55–09:00

INTRODUCTION Sofia Feltzing, Chairman of the Program Committee

WELCOME REMARKSTorbjörn von Schantz, Vice-Chancellor, Lund University

PRESENTATION OF THE KNUT AND ALICE WALLENBERG FOUNDATIONPeter Wallenberg Jr and Göran Sandberg, the Knut and Alice Wallenberg Foundation

THE ROYAL SWEDISH ACADEMY OF SCIENCESGöran K. Hansson, Secretary General, the Royal Swedish Academy of Sciences

09:00–09:40 RECENT TRENDS IN ASTROPHYSICS AND CRUCIAL PROBLEMS FOR THE FUTURESir Martin Rees, Cambridge University

09:40–10:20 UNDERSTANDING THE FORMATION OF THE EARTH, SUN, AND STARS – A CHALLENGE FOR THE NEXT GENERATIONBruce Elmegreen, IBM Research

10:20–10:50 COFFEE

10:50–11:05 THE FUTURE OF PLANETARY ARCHITECTURES Melvyn B. Davies, Lund University

11:05–11:20 FORMING HABITABLE PLANETS ON THE COMPUTERAnders Johansen, Lund University

11:20–11:35 TOWARD DIRECT STUDIES OF HABITABLE EXOPLANETSMarkus Janson, Stockholm University

11:35–11:50 DOING CHEMICAL ANALYSIS OF EXOPLANETARY ATMOSPHERESNikolai Piskunov, Uppsala University

PROGRAMBIG QUESTIONS IN ASTROPHYSICS – THE NEXT DECADES

A SYMPOSIUM TO CELEBRATE THE KNUT AND ALICE WALLENBERG FOUNDATION’S 100-YEAR ANNIVERSARY

Tuesday, April 4, 2017, Grand Auditorium, Lux, Helgonavägen 3, Lund



11:50–12:50 LUNCH

12:50–13:30 FRONTIERS IN GALAXY EVOLUTION: ACHIEVEMENTS SO FAR AND DISCOVERIES AHEAD Marcella Carollo, ETH Zürich

13:30–14:10 MAKING THE UNIVERSE AND ITS CONTENTS – WHAT TO EXPLORE IN THE COMING DECADESVolker Springel, Heidelberg University and HITS

14:10–14:25 THE (ULTRA-) LOW SURFACE BRIGHTNESS UNIVERSEMatthew Hayes, Stockholm University

14:25–14:40 EARLY GALAXY EVOLUTION – THE FAR-INFRARED PERSPECTIVEKirsten Kraiberg Knudsen, Chalmers

14:40–14:55 THE NEW MILKY WAYThomas Bensby, Lund University

14:55–15:25 COFFEE

15:25–16:05 ESO AND THE EXTREMELY LARGE TELESCOPE: THE FUTURE OF EUROPEAN GROUND-BASED ASTRONOMY Michele Cirasuolo, European Southern Observatory (ESO)

16:05–16:20 UNDERSTANDING SOLAR MAGNETIC FIELDS AND THEIR ROLE IN HEATING THE OUTER SOLAR ATMOSPHERE AND IN PRODUCING SPACE WEATHERGöran Scharmer, Stockholm University, Institute for Solar Physics

16:20–17:00 THE TRANSIENT REVOLUTION IN ASTROPHYSICSAvishay Gal-Yam, Wiezmann Institute of Science

17:00–17:15 SUPERNOVA 1987A AT 30 YEARSJosefin Larsson, KTH Royal Institute of Technology

17:15–17:30 HUNTING FOR SUPERNOVAE Jesper Sollerman, Stockholm University

17:30–17:45 ASTROPHYSICAL DETECTION OF PARTICLE DARK MATTER – NOW AND IN THE NEXT DECADEJan Conrad, Stockholm University

17:45–17:50 CLOSING/CONCLUDING REMARKS


KNUT & AL ICE WALLENBERG FOUNDAT ION

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Powerful instruments had led to astonishing progress in tracing the emergence of atoms, galaxies, stars and planets from a mysterious ’beginning’ nearly 14 billion years ago. Unmanned spacecraft have visited the other planets of our Solar System (and some of their moons), beaming back pictures of varied and distinctive worlds. An exciting development in the last two decades has been the realisation that many other stars are orbited by retinues of planets—some resembling our Earth (and capable of harboring life).

Looking further afield, observers can probe galaxies and the massive back holes at their centres and can check models of their evolution by detecting objects all the way back to an epoch only a billion years after the ’big bang’. Indeed we can trace pre-galactic history with some confidence back to a nanosecond after the ’big bang’.

But the key parameters of our expanding universe—the expansion rate, the geometry and the content—were established far earlier still, when the physics is still conjectural but is being constrained, especially by precision measurements of the microwave background. These advances pose new questions. Illustrated lecture will attempt to address such issues.

RECENT TRENDS IN ASTROPHYSICS AND CRUCIAL PROBLEMS FOR THE FUTURESir Martin Rees, Cambridge University

SIR MARTIN REES is a cosmologist and space scientist. His research interests include galaxy formation, active galactic nuclei, black holes, gamma-ray bursts, and more speculative aspects of cosmology. He is based in Cambridge, where he has been Director of the Institute of Astronomy, a Research Professor, and Master of Trinity College. He was President of the Royal Society (the UK’s academy of science) during 2005–2010. In 2005 he was appointed to the UK’s House of Lords. He has received many international awards for his research, and belongs to numerous academies including the National Academy of Sciences, the Swedish Academy, the Russian Academy and thePontifical Academy. He has served on many bodies connected with international collaboration in science—and those that address threats stemming from humanity’s ever-heavier ’footprint’ on the planet, and the runaway consequences of ever more powerful technologies.He lectures,, writes and broadcasts widely for general audiences. His books include ’Before the Beginning’, ’Our Final Century?’ ’Just Six Numbers’, ’Our Cosmic Habitat’, ’Gravity’s Fatal Attraction’ (with M Begelman) , and ’From Here to Infinity: Scientific Horizons’ A further book, ’What we still don’t know’ is forthcoming.



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New stars are observed to be forming all around us in the Milky Way and in other galaxies by a common process where turbulent magnetic gas collapses under its own weight into dense filaments and clumps. Tiny dust particles carried along with this gas block out the surrounding starlight until the temperature in the gas drops to near absolute zero, at which point the pressure is overwhelmed by gravity and the collapse becomes unstoppable. What forms in the center is a proto-star that shines red from the heat of compression, and an orbiting disk of gas and dust that glows in the far-infrared from cold thermal emission of dust. The proto-star continues to radiate, shrink, and heat up until nuclear fusion begins in the center. The disk typically forms planets. Observations now show that most proto-stars have far-infrared disks and most stars have planets. What happens next is not yet clear, but detailed models suggest that in the next few million years, the dust in the inner disk coagulates into rocks and boulders that grow and gravitate into rocky proto-planets, eventually forming new Earths, while the gas and dust in the outer regions collapse through gravitational forces, forming new planetary giants like Jupiter. This talk will review our current understanding of the formation of the Earth, Sun, and Stars, and will highlight the new telescopes and instruments that are being built for the next generation to witness this process in even more detail.

UNDERSTANDING THE FORMATION OF THE EARTH, SUN, AND STARS – A CHALLENGE FOR

THE NEXT GENERATIONBruce Elmegreen, IBM Research

DR. BRUCE G. ELMEGREEN works in IBM’s Research Division studying star formation and interstellar matter. He received the Dannie Heineman Prize for Astrophysics and currently serves as President of the Division on Interstellar Matter and Local Universe of the International Astronomical Union. He got his doctorate at Princeton University, was a Junior Fellow at Harvard University, and a faculty member at Columbia University before joining IBM.



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Observations over the last twenty years have revealed a myriad of planetary systems around other stars. In this talk I will show how observations have given us several surprises, revealing planetary systems quite different from our own Solar System. These observations have led to significant developments in our understanding of how planetary systems form and subsequently evolve. I will review some of the important questions we wish to answer in the coming decades and explain how answering these questions will help us to understand what fraction of Sun-like stars possess planetary systems similar to our own Solar System.

THE FUTURE OF PLANETARY ARCHITECTURESMelvyn B. Davies, Lund University

MELVIN B. DAVIES is a theoretical astrophysicist who studies the formation and evolution of stellar clusters and their contents. He considers how encounters within stellar clusters affect the formation and subsequent evolution of planetary systems, compact binaries and black holes. Melvyn studied physics as an undergraduate at Jesus College, Oxford. He was a PhD student in astronomy at Harvard University completing his PhD in 1992. He was then an R.C. Tolman Fellow in theoretical astrophysics at the California Institute of Technology, before returning to the UK, taking up a Royal Society Research Fellowship at University of Cambridge. He took up a permanent faculty position at University of Leicester in 1998, becoming Reader in 2003. He moved to Lund University in 2004 as a KVA Research Fellow, becoming professor in 2005.



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Several thousand exoplanets – planets that orbit stars other than the Sun – have been discovered since the first exoplanet was detected in 1995. The ever-expanding catalogue of exoplanets has revealed that nature forms a surprising variety of planetary systems. Some stars host gas-giant planets akin to Jupiter in close proximity to the host star, while other systems boast multiple super-Earths, more massive counterparts to the terrestrial planets in the Solar System. Stars with higher luminosity than the Sun are sometimes orbited by massive gas giants in very wide orbits. I will present a coherent theoretical framework that explains the formation of this diversity of planets. I will discuss ongoing efforts to detect small planets in the habitable zone of the host star and highlight pathways to, and challenges in, modelling the formation of terrestrial planets and the delivery of life’s chemical building blocks to young planets.

FORMING HABITABLE PLANETS ON THE COMPUTER

Anders Johansen, Lund University

ANDERS JOHANSEN Anders Johansen works on computer simulations of planet formation. He obtained his PhD degree from the Max Planck Institute for Astronomy and Heidelberg University in 2007. He moved to Lund University in 2010 and is now a professor of astronomy. In 2013 he received the “Harold C. Urey Prize” from the American Astronomical Society and in 2015 the “Sten von Friesen Prize” from the Royal Physiographic Society in Lund.



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TOWARD DIRECT STUDIES OF HABITABLE EXPLANETSMarkus Janson, Stockholm University

The capacity of exoplanet imaging is steadily improving, and by now it is possible to acquire high S/N spectra of young high-mass planets in wide orbits, allowing for detailed studies of their chemical compositions, as well as fundamental physical characteristics such as their tempera-ture, radius, metallicity, and rotation rate. With improved techniques and instruments, the aim for the next decades is to push the detection limits of such studies to include Earth-like planets in the classical habitable zones of their stars. I will outline the next steps with both ground- and space-based facilities that will bring us toward this goal, as well as discuss target identification strategies. The complementarity of direct imaging to other exoplanet detection and characterization techniques will also be discussed. Direct imaging of Earth-like planets will most likely provide the first falsifiable and reproducible evidence regarding the distribution of habitability and life in our galaxy, and is achievable within the next decades.

MARKUS JANSON is a docent and Wallenberg Academy Fellow at Stockholm University. Having completed his PhD at the Max Planck Institute for Astronomy in Heidelberg in 2008, he has since held the Reinhardt and Hubble fellowships at University of Toronto and Princeton, respectively. His research involves studies of extrasolar planets through imaging and complementary techniques, as well as the circumstellar disks in which planets form and reside. He also studies stellar multiplicity and its influence on the formation and architecture of extrasolar systems.



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I will present the current status of the characterisation of the exoplanetary atmospheres using transit and reflection spectroscopy, describe the upcoming instrumentation aimed at achieving major progress in this field and outline what observational data we can/should expect to become available in the coming few years.

DOING CHEMICAL ANALYSIS OF EXOPLANETARY ATMOSPHERES

Nikolai Piskunov, Uppsala University

NIKOLAI PISKUNOV graduated from Moscow State University in 1980, worked for Russian Academy developing Doppler Imaging methods, defended his PhD at Tartu University in 1985 and then moved to Helsinki University in 1991 to work on active late-type stars. In 1993–1996 he worked for the University of Western Ontario and JILA in Boulder (CO). During this period Piskunov continued working on stellar activity and several instrumentation projects. Since 1996 he is astronomy professor in Uppsala.



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Deep surveys of the distant Universe have revealed the broad outlines of where, when, and at what rate stars have been forming in the Universe. Not least we have understood that, at any epoch, most stars form in dark matter haloes of a particular characteristic mass, and have broadly charted the phenomenology behind the decrease in the efficiency of star formation in halos that are either either more or less massive than this characteristic mass. The physical processes behind this gross evolutionary behavior are however largely unknown.

Hydrodynamic simulations in a Cold Dark Matter universe still parametrize key physics through sub-grid recipes, due to the enormous dynamic ranges involved, and also do not yet include physical processes that may be fundamental in establishing galactic equilibrium. Therefore they are limited by issues of uniqueness and degeneracies even when starting from identical initial conditions. On the other hand, observational studies are faced with a bewildering variety of phenomena. Disentangling the relative importance of these, and establishing the underlying physical causality behind even very tight observational correlations, is proving to be a difficult task.

The next generation of large surveys, telescopes and computers will confront these challenges by producing petabytes and possibly even exabytes of data. A philosophical challenge is raised in turn, namely whether data mining through machine learning algorithms can provide a full understanding of reality without an Ansatz for a physically-motivated model for the origins and evolution of our Universe.

FRONTIERS IN GALAXY EVOLUTION: ACHIEVEMENTS SO FAR AND DISCOVERIES AHEADMarcella Carollo, ETH Zürich

MARCELLA CAROLLO is since 2002 a Professor at the ETH Zurich. She received her PhD in 1994 from the Ludwig Maximilians Universität (Munich, Germany), then was a Fellow at Leiden University and Johns Hopkins University in Baltimore before moving as faculty to Columbia University in 1999. Her main research interests focus on understanding the formation of galaxies and the evolution of structure in the Universe, from the earliest epochs down to the present time. She is involved in several of the next generation surveys that will address open challenges in galaxy evolution.



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MAKING THE UNIVERSE AND ITS CONTENTS – WHAT TO EXPLORE

IN THE COMING DECADESVolker Springel, Heidelberg University and HITS

Arguably one of the most surprising discoveries of modern cosmology is that the Universe features a rather strange composition, with unknown dark matter and dark energy components domina-ting today’s energy density. Numerical simulations have played a pivotal role in demonstrating that this seemingly unlikely scenario gives rise to a remarkably successful theory for structure formation. We now understand in a fair amount of detail how an intricate cosmic web of structures emerges from the simple initial conditions left behind by the Big Bang. Nowadays, modern hydrodynamical simulations have become an important tool to study complex dynamics in the baryonic sector, allowing us to follow how hydrogen and helium gases condense out in galaxies, form stars, and populate the predicted dark matter structures. However, we still struggle to understand basic aspects of the involved processes, such as the regulation of star formation, which appears rather inefficient on a global scale, defying simple theoretical expectations. In this talk, I will review our current understanding of cosmic structure formation and some of the most pressing open questions. I will also discuss the ongoing quest of using structure formation to constrain the true physical nature of dark matter and dark energy.

VOLKER SPRINGEL studied physics at the University of Tübingen and the University of California at Berkeley, and received his PhD degree in the year 2000 from the Ludwig-Maximilians University in Munich. He now works at the Heidelberg Institute for Theoretical Studies and the Center for Astronomy at Heidelberg University, where he was appointed Professor for Theoretical Astrophysics in 2010. He is a specialist in computational astrophysics and works, in particular, on galaxy formation and cosmology. At the moment his main research interests are concerned with the regulation of star formation through supernova explosions and supermassive black holes. He has been awarded for his research work with the Otto-Hahn Medal of the Max-Planck Society, the Heinz-Maier Leibnitz Prize of the German Science Foundation, and the Klung-Wilhelmy Weberbank Prize for Physics. He is also a member of the German National Academy of Sciences, Leopoldina.



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THE (ULTRA-) LOW SURFACE BRIGHTNESS UNIVERSE Matthew Hayes, Stockholm University

In the canonical picture of galaxy formation, galaxies are built hierarchically through the mergers and accretion of smaller parts, in which framework current theoretical models are able to make very precise predictions. However major discrepancies remain between these expectations and the amount of stellar and gaseous material, and the number of low-mass galaxies, that surround massive nearby systems. This may be the result of a severe observational bias that has been implicit in observational astronomy for decades. Trends in science and telescopic design have focused upon finding fainter compact objects at larger distances and, admittedly, have overwhelmingly enhanced our view of the cosmos. However most modern telescopes are not optimized to detect faint light if it is spread over large areas of sky. Preliminary observations on small dedicated facilities, and even amateur telescopes, have recently delivered images that suggest there could be a large population of extended low-surface brightness galaxies lurking just below our current detection limit of current surveys. However to truly assess this, and precisely determine the distribution of baryonic matter in the modern universe, an overhaul in telescopic facilities is needed. In my talk I will review the current state-of-the-art in low-surface brightness astronomy, and show the limits of what can be achieved with current telescopes. I will discuss how the picture of stellar material and extragalactic gas will be enhanced with future observatories such as the Large Scale Synoptic Telescope (LSST) and dedicated satellite missions. I will give a summary of the (many) technical and observational challenges such studies will face, as well as their likely solutions, where we expect the frontier to lie in the coming decades.

MATTHEW HAYES, born in Malvern, Worcestershire, United Kingdom. He took his Master of Physics degree from the University of Leeds in1999 and his Doctor of Philosophy from Stockholm University in 2007. He held postdoctoral research positions at the Observatory of the University of Geneva, Swizerland (2007–2010) and at the Institute of Research in Astrophysics and Planetology in Toulouse, France (2010–2013). He currently holds the position as Associate professor of Astrophysics at Stockholm University. He has financial research support from the Swedish Research Council, the Swedish National Space Board, SNSB and the Knut and Alice Wallenberg Foundation (WAF-fellow since 2015). He has been the principle investigator of observational programmes seven times using the Hubble Space Telescope and 19 times using the Very Large Telescope facilities at the European Southern Observatory.



The field of galaxy formation and evolution has gone through a major development in the past two decades. It has been realised that cosmologically distant galaxies have orders of magnitude increased star formation rate and black hole growth activity compared to present-day galaxies. Also it has been understood that a significant part of the on-going star formation activity is obscured by cosmic dust. In this talk I will show the fundamental progress that observations at far-infrared and mm wavelength provide for our understanding of galaxy evolution. It is at those wavelengths we can view the gas and dust that fuels the on-going star formation and thus galaxy build-up.

I will focus on the first few billion years after the big bang, specifically discussing some of the major recent results from the Atacama Large Millimeter Array (ALMA, in Chile). These results do not only impact our understanding of how galaxies form, but also set the stage for future progress.

EARLY GALAXY EVOLUTION – THE FAR-INFRARED PERSPECTIVE

Kirsten Kraiberg Knudsen, Chalmers

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KIRSTEN KRAIBERG KNUDSEN, Wallenberg Academy Fellow, is an astronomer at Chalmers University of Technology. She has an international background with a PhD from Leiden and postdoc positions in Germany. Her research is focused on understanding early phases of galaxy evolution through studying cosmologically distant galaxies. To conduct her research she successfully use world-leading telescopes such as ALMA. In 2014 she became a member of the Young Academy of Sweden.



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Understanding how spiral galaxies like our Milky Way formed and evolved to its current state is a major goal in galactic research. To do that we need a complete and accurate picture of the structure and composition of the galaxy in question. However, the picture of our home galaxy, the Milky Way, has changed dramatically the last few decades. Previously the Milky Way was seen as a rather simple spiral galaxy with a rotating disk of stars about 100000 light years in diameter, surrounded by a diffuse halo of stars, and a central spherical bulge. Starting in the 1980s it has been discovered that the Milky Way actually contains two disk populations, that the halo harbours a plethora of remnants from mergers between the Milky Way and other galaxies, and that the bulge contains a peanut-shaped bar structure and a complicated mixture of stars from many of the other major Galactic stellar populations. This talk will describe our ongoing efforts to map the detailed structure of the Milky Way. Main focus will be on major spectroscopic surveys such as The Gaia-ESO Survey, WEAVE, and 4MOST that will provide detailed elemental abundance data, kinematics, and stellar ages for several millions of stars the coming 10–15 years. Together with the Gaia astrometric data, this will form a gold mine to map the chemical and dynamical properties of millions of stars and stellar populations, enabling us to probe the origin and evolution of the nearest large spiral galaxy, our own Milky Way.

THE NEW MILKY WAYThomas Bensby, Lund University

THOMAS BENSBY. After obtaining a PhD in Lund in 2004, I have worked as a postdoc at University of Michigan and as an ESO Fellow at the Very Large Telescope at the European Southern Observatory on Cerro Paranal in Chile. Now I am a senior lecturer at Lund University. My research focuses on Galactic archaeology, unravelling the detailed structure of our home galaxy, the Milky Way, in order to constrain its origin and evolution, and to understand galaxy formation in general.



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The European Southern Observatory (ESO) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive astronomical observatory. ESO provides state-of-the-art research facilities to astronomers and astrophysicists, allowing them to conduct front-line science.

First I will provide an overview of the ESO facilities at Cerro Paranal in Chile and the instrumentation programme. I will present the latest status of the current and new instrumentation, focusing on their scientific potential.

Then I will highlight the key science drivers of the new ESO’s flagship facility: the European Extremely Large Telescope.

The E-ELT is now under construction and with its 39-metre primary mirror it will be the largest optical/near-IR telescope in the world. I will present an overview of the E-ELT Programme, presenting the latest status of the telescope, its instrumentation and the scientific synergies with other facilities.

ESO AND THE EXTREMELY LARGE TELESCOPE: THE FUTURE OF EUROPEAN GROUND-BASED

ASTRONOMYMichele Cirasuolo, European Southern Observatory (ESO)

DR. MICHELE CIRASUOLO is an astrophysicist at the European Southern Observatory and Programme Scientist for the Extremely Large Telescope. His main topic of research is understanding the formation and evolution of galaxies across cosmic time, both from theoretical and observational point of view. He has also an extensive track record in developing astronomical instrumentation.



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UNDERSTANDING SOLAR MAGNETIC FIELDS AND THEIR ROLE IN HEATING THE OUTER SOLAR ATMOSPHERE AND IN PRODUCING SPACE WEATHERGöran Scharmer, Stockholm University, Institute for Solar Physics

Since the dawn of astrophysics, understanding the solar atmospheres always was in some respects possible but in other respects overwhelmingly difficult. Early on, simple one dimensional models sufficed to explain fundamental properties of the solar atmosphere, such as why the temperature decreases outwards. For many decades, however, explaining why the temperature instead increases outwards in the outermost layers was mostly open to pure speculations. Without direct observational evidence of the heating mechanisms at work, and without a solid theory to explain the observations, conclusions were not really possible.

Today, we are in a golden era where genuine breakthroughs in our understanding of the hottest layers of the solar atmosphere, the chromosphere and corona, are within reach. The very best solar telescopes (where the Swedish 1-m Solar Telescope is a contender) now see much sharper details than 10 years ago, thanks to adaptive optics. In addition, sophisticated instruments now allow unprecedented diagnostics of the chromosphere and the hotter layers above. We can already conclude that magnetic fields are somehow involved in the heating of the gas and we know that waves, electrical currents magnetic reconnection all may release substantial energy. But which of these mechanisms dominates? We will present state-of-the-art observations and the best numerical simulations that aim at answering this question and that ultimately will lead to an understanding of explosive events near sunspots and the origin of space weather.

GÖRAN SCHARMER is Professor and Director of the Institute for Solar Physics at Stockholm University. He has been responsible for the development of the Swedish 1-meter solar Telescope and various instrumentation for this telescope, including the dual Fabry-Pérot system CHROMIS. This instrument is built for studying the upper solar chromosphere, primarily using the CA II H&K lines. In 2004 Professor Scharmer obtained the Lennart Nilsson Award and in 2008 he was awarded the Tycho Brahe Pirze of the European Astronomical Society.



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The study of time-variable astrophysical phenomena has a long history, and has led to many fundamental discoveries, from the size of the universe revealed by Cepheid variable stars to the Nobel-prize winning discovery of cosmic acceleration using exploding Type Ia supernovae. And yet, our knowledge of the transient universe was limited by large number of celestial objects visible in the vast sky. We are know in the dawn of an era of discovery in time-domain astrophysics, enabled by the combination of maturing digital detector technologies, high-power computing, and globally-coordinated scientific networks. Starting in just a few months, we will be able to view most of the sky in the form of a cosmic movie, observing the heavens in visible light as they change on time scales of days. In somewhat smaller areas, we will observe variable phenomena on timescales of hours, and in few years time, also of minutes or shorter. At the same time, time- domain studies in other parts of the electro-magentic spectrum and beyond (gravitational waves, neutrinos) are also rapidly evolving. I will review some of the emerging new discoveries based on the most powerful surveys conducted so far, with a view towards forthcoming revolution in the near future.

THE TRANSIENT REVOLUTION IN ASTROPHYSICS

Avishay Gal-Yam, Wiezmann Institute of Science

AVISHAY GAL-YAM. Born in Jerusalem, in 1970, Prof. Avishay Gal-Yam earned his BSc in physics and mathematics in 1996 and his PhD in physics and astronomy in 2003 at Tel Aviv University. He received NASA’s prestigious Hubble postdoctoral fellowship and spent four years conducting research at the California Institute of Technology. He joined the Weizmann Institute of Science in 2007. Prof. Gal-Yam attempts to identify the stars responsible for spectacular stellar explosions called supernovae. Solving these mysteries can provide vital clues for both the origins of the elements that make up the periodic table – including those necessary for life itself – and for cosmological questions about the origin and fate of the universe. For example, Prof. Gal Yam and his team of graduate students and postdoctoral fellows reported the discovery of two new types of supernova explosions. One very faint type – that occurs when helium detonates – appears to produce significantly more calcium (vital for life as we know it) and titanium than were thought possible, and probably contributes a significant portion of these critical elements in the cosmos. On the other hand his team discovered massive superluminous supernovae. These are 10 to 100 times more powerful than any previously known type and may be similar to the first supernova explosions to have occurred after the big bang. Recently, The Gal-Yam team has been focusing on studies of massive stars observed “as they explode” – these works shed light on the nature and underlying physics of these cosmic explosions.



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Supernova 1987A is the most nearby supernova in the era of modern telescopes. Its proximity has enabled a number of unique discoveries and even today, thirty years after the explosion, it continues to provide us with new insights about exploding stars. In this talk I will discuss some of the most recent results on 1987A, including observations that reveal the 3D structure of the inner ejecta, the discovery of molecules within the ejecta, as well as the interaction between the ejecta and the circumstellar medium. I will also discuss what the future might bring for this unique object.

SUPERNOVA 1987A AT 30 YEARSJosefin Larsson, KTH Royal Institute of Technology

JOSEFIN LARSSON is an assistant professor at KTH Royal Institute of Technology in Stockholm. She studied physics and astronomi at Lund University and obtained her PhD from the University of Cambridge. She was awarded the Göran Gustafsson large prize for young researchers in 2013 and was appointed as a Wallenberg Academy Fellow in 2015. Her research interests include supernovae, gamma-ray bursts and active galaxies.



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HUNTING FOR SUPERNOVAEJesper Sollerman, Stockholm University

Supernovae are exploding stars, transient phenomena in the night sky. Astronomically they are connected to a diverse number of research areas; supernova cosmology, massive stellar evolution, nucleosynthesis and chemical enrichment of the universe. Observationally they require systematic searches and rapid follow-up. The Zwicky Transient Facility is the next large effort to search the transient sky, allowing us to find more, younger and different supernovae. For those not entirely dedicated to supernovae, ZTF will also help search for other transients; With a new experiment like this, we of course hope for entirely new classes of transients, perhaps connected to LIGO gravitational wave detections.

JESPER SOLLERMAN is professor in astronomy at Stockholm University. As an observational astronomer he is interested in finding new transients in the sky. With a background in searching for Type Ia supernovae for supernova cosmology and gamma-ray bursts and their connection to supernovae, he is now fully occupied with the Zwicky Transient Facility (ZTF), the upcoming (2017) next generation of supernova finding instruments. Sollerman leads the Oskar Klein Centre involvement in ZTF, funded by KAW. He is also a science journalist and chairman of the Swedish Astronomical Society.



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ASTROPHYSICAL DETECTION OF PARTICLE DARK MATTER – NOW AND IN THE NEXT DECADEJan Conrad, Stockholm University

The existence of dark matter is established beyond reasonable doubt. The evidence suggest that it is made of new types of particles hitherto unknown. In our talk we will present the status and outlook for detecting this particles from the cosmos, deep underground in detectors with very low background and high in the sky with telescopes to detect gamma rays. The next decade is crucial: if our current paradigm is correct, a detection should be imminent.

JAN CONRAD, professor i astropartikelfysik. Born 1973, PhD from Uppsala University in 2003 focusing on neutrinoastrophysics. He works in the area where particle physics and astrophysics meet and has recently been focused on detection of dark matter. The experiments are build in international collaborations in which Conrad had leading roles and has been responsible for the Swedish contribution. He has mainly worked on developing new and widely used methods for data analysis, which lead to internationally reckognized break-through in the search for dark matter in 2011. Conrad has been research fellow at the CERN laboratory in Geneva between 2004 and 2005 as well as VR research fellow at KTH between 2006 and 2007. He has been KVA research fellow from 2009–2013, Wallenberg Academy Fellow from 2012. Conrad is coauthor on about 300 scientfic articles. Conrad is married and has two children.



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The Knut and Alice Wallenberg Foundation was established in 1917. The Foundation’s aim is to benefit Sweden by supporting Swedish basic research and education, mainly in medicine, technology and the natural sciences. This is achieved through grants to excellent researchers and to projects.

During the Foundation’s 100 years SEK 24 billion has been awarded in grants for excellent research and education, of which SEK 1.7 billion annually in recent years, making the Foundation one of the largest private funders of scientific research in Europe.

The Royal Swedish Academy of Sciences is an independent, non-governmental organisation with a charter that, in its first article, defines its function as promoting the sciences and strengthening their influence in society. The Academy promotes science of the highest quality by fostering development and innovation in Swedish research. It enhances the status of science in society by drawing attention to key social issues, examining them in scientific terms and communicating the results, and joins in cooperation on global issues, with the aim of being an international scientific proponent of sustainable development.

KNUT AND ALICE WALLENBERG FOUNDATION

THE ROYAL SWEDISH ACADEMY OF SCIENCES



BIG QUESTIONS IN ASTROPHYSICS – THE NEXT DECADES

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BIG QUESTIONS IN ASTROPHYSICS – THE NEXT DECADES · ASTROPHYSICS – THE NEXT DECADES. Keynote talks during the symposium will cover major topics in contemporary astrophysics, including

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