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Thirty Meter Telescope Detailed Science Case: 2015 TMT.PSC.TEC.07.007.REL02 PAGE 1 DETAILEDThirty SCIENCE CASE: Meter 2015 TelescopeApril 29, 2015 Detailed Science Case: 2015 International Science Development Teams & TMT Science Advisory Committee TMT.PSC.TEC.07.007.REL02 PAGE I DETAILED SCIENCE CASE: 2015 April 29, 2015 Front cover: Shown is the Thirty Meter Telescope during nightime operations using the Laser Guide Star Facility (LGSF). The LGSF will create an asterism of stars, each asterism specifically chosen according to the particular adaptive optics system being used and the science program being conducted. TMT.PSC.TEC.07.007.REL02 PAGE II DETAILED SCIENCE CASE: 2015 April 29, 2015 DETAILED SCIENCE CASE: 2015 TMT.PSC.TEC.07.007.REL02 1 DATE: (April 29, 2015) Low resolution version Full resolution version available at: http://www.tmt.org/science-case © Copyright 2015 TMT Observatory Corporation arxiv.org granted perpetual, non-exclusive license to distribute this article 1 Minor revisions made 6/3/2015 to correct spelling, acknowledgements and references TMT.PSC.TEC.07.007.REL02 PAGE III DETAILED SCIENCE CASE: 2015 April 29, 2015 PREFACE For tens of thousands of years humans have looked upward and tried to find meaning in what they see in the sky, trying to understand the context in which they and their world exists. Consequently, astronomy is the oldest of the sciences. Since Aristotle began systematically recording the motions of the planets and formulating the first models of the universe there have been over 2350 years of scientific study of the sky. The earliest scientists explained their observations with the earth-centered universe model and little more than two millennia later we now live in an age where we are beginning to characterize exoplanets and systematically probing the evolution of the universe from its earliest moments to the present day. Human understanding of the universe has leapt forward incrementally with each new technology. Firstly with improvements in the methods of observing with the naked eye and the recording of observations, then, over 400 years ago with Galileo and the first telescopes. There followed a continuing constant evolution to larger collecting surfaces. Larger lenses and much larger mirrors were developed and within the last 150 years the use of photographic plates and spectroscopy coupled with improved mechanical tracking allowed huge advances. The sphere of the observable universe increased to distances and times when the universe was considerably younger than today. With the introduction and availability within the last few decades of electronic detectors, telescopes in space, supercomputing, segmented mirror technologies and adaptive optics, every improvement has allowed existing questions to be answered, spawned the development of new ones and led to almost countless unexpected discoveries. As our level of knowledge grows, the next level of questions that arise require facilities with even greater capabilities to gather the observations needed to answer them. With each incremental step in capability, the resulting new questions require an even larger step in capability in order to be answered. No single university, no single country, not even a whole continent has the technological resources to build these facilities. In order to answer the key questions about the structure and evolution of the universe and to explore the enigmatic processes, environments and bodies that pervade the universe the Thirty Meter Telescope Observatory was conceived. We have now embarked on the construction of the Thirty Meter Telescope and its capable suite of first light instruments. Over the past decade a strong and capable international partnership has been established, bringing together the necessary resources, building new international scientific collaborations, developing the design and preparing to build the Thirty Meter Telescope. The Thirty Meter Telescope will be an extremely powerful facility in its own right and will comprise a key component of the future suite of astronomical facilities including JWST, LSST and ALMA. In the pursuit of scientific knowledge, the international partnership brings together the combination of scientific and engineering expertise and industrial capabilities needed to build and operate the TMT and provide each partner with cutting edge facilities to support their research communities as well as creating immeasurable benefits for broader society. Warren Skidmore (editor-in-chief) TMT.PSC.TEC.07.007.REL02 PAGE IV DETAILED SCIENCE CASE: 2015 April 29, 2015 TABLE OF CONTENTS 1. INTRODUCTION 1 1.1 Purpose and Scope ................................................................................................... 1 1.2 Applicable and Reference Documents and Change Record .................................... 1 2. OVERVIEW 2 2.1 The Big Picture .......................................................................................................... 2 2.2 The Big Questions ..................................................................................................... 4 2.3 The Required Tools ................................................................................................... 5 2.3.1 First Light Suite ................................................................................................... 7 2.3.2 First Light Instruments Exposure Time Calculators ........................................... 7 2.3.3 Future Instruments .............................................................................................. 7 2.3.4 Observatory Operations ...................................................................................... 8 3. FUNDAMENTAL PHYSICS AND COSMOLOGY 9 3.1 The nature of dark matter .......................................................................................... 9 3.1.1 Dwarf galaxy radial mass profiles ....................................................................... 9 3.1.2 Dark Matter Substructure .................................................................................. 11 3.1.3 Dark Matter self-interaction cross-section ........................................................ 13 3.1.4 Baryonic power spectrum ................................................................................. 14 3.1.5 Dark energy and modified gravity ..................................................................... 15 3.1.6 Time-delay cosmography ................................................................................. 16 3.1.7 Cosmology from clusters of Galaxies ............................................................... 17 3.1.8 Tests of general relativity .................................................................................. 18 3.2 Physics of extreme objects – Neutron Stars ........................................................... 19 3.3 Variation of Fundamental Physical Constants ........................................................ 20 4. EARLY UNIVERSE 22 4.1 Early galaxies and cosmic reionization ................................................................... 22 4.1.1 Uncovering primordial stellar systems with TMT .............................................. 23 4.1.2 Detecting the sources of reionization ................................................................ 25 4.1.3 The process and history of reionization ............................................................ 26 4.2 Angular sizes and the synergy with JWST and future space missions .................. 28 4.3 Gravitational Lensing ............................................................................................... 30 5. GALAXY FORMATION AND THE INTERGALACTIC MEDIUM 32 5.1 The Peak era of galaxy assembly ........................................................................... 33 5.1.1 TMT and galaxy formation ................................................................................ 33 5.1.2 How does the distribution of dark matter relate to the luminous stars and gas we see? .................................................................................................................. 35 TMT.PSC.TEC.07.007.REL02 PAGE V DETAILED SCIENCE CASE: 2015 April 29, 2015 5.1.3 The Growth of Stars: Star-Formation Histories, Dust, and Chemical Evolution ........................................................................................................................ 36 5.1.4 The formation of passive galaxies and the birth of the Hubble Sequence ...... 37 5.1.5 The Stellar Initial Mass Function, Early Black Holes and the Growth of Quasars ......................................................................................................................... 38 5.1.6 The Census of Baryons and the Baryon Cycle ................................................ 40 5.1.7 Spatial dissection of forming galaxies ............................................................... 42 5.1 The Age of Maturity and Quiescence ...................................................................... 44 5.1.1 Morphological and Kinematic Growth of Galaxies ........................................... 44 5.1.2 Feedback and the Physics of Galaxy Quenching ............................................ 51 5.1.3 The Influence of Local and Large-Scale Environment ..................................... 52 5.2 The Intergalactic Medium ........................................................................................ 57 5.2.1 Background ....................................................................................................... 57 5.2.2 TMT and the IGM
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