KEK Report 2012-4 October 2012 A/M Energy Recovery Linac Conceptual Design Report High Energy Accelerator Research Organization © High Energy Accelerator Research Organization (KEK), 2012 KEK Reports are available from: High Energy Accelerator Research Organization (KEK) 1-1 Oho, Tsukuba-shi Ibaraki-ken, 305-0801 JAPAN Phone: +81-29-864-5137 Fax: +81-29-864-4604 E-mail: [email protected] Internet: http://www.kek.jp Energy Recovery Linac Conceptual Design Report CONTENTS CONTRIBUTORS...............................................................................................................................iii Chapter.1.Executive.Summary.........................................................................................................1 . 1.1. Introduction . 1.2. Capabilities Chapter.2.Why.ERL.is.Needed..........................................................................................................3 Chapter.3.Enabling.Methodologies.................................................................................................5 . 3.1. Diffraction.imaging.using.coherent.beams 3.1.1 Introduction 3.1.2 Scientific goals and challenges 3.1.3 Current status and limitations 3.1.4 Future prospects with ERL . 3.2. Macromolecular.structure.from.nanocrystals 3.2.1 Introduction 3.2.2 Scientific goals and challenges 3.2.3 Current status and limitations 3.2.4 Future prospects with ERL . 3.3. Capturing.ultrafast.phenomena 3.3.1 Introduction 3.3.2 Scientific goals and challenges 3.3.3 Current status and limitations 3.3.4 Future prospects with ERL and XFEL-O . 3.4. Coherent.nanobeam.and.imaging 3.4.1 Introduction 3.4.2 Scientific goals and challenges 3.4.3 Current status and limitations 3.4.4 Future prospects with ERL . 3.5. X-ray.photon.correlation.spectroscopy 3.5.1 Introduction 3.5.2 Scientific goals and challenges 3.5.3 Current status and limitations 3.5.4 Future prospects with ERL Chapter.4.Science.Cases................................................................................................................18 . 4.1. Natural.photosynthesis 4.1.1 Oxygen evolving manganese complex in photosystem II – structural approach 4.1.2 Oxygen evolving manganese complex in photosystem II – spectroscopic approach 4.1.3 Electron transfer reaction in photosynthesis . 4.2. Catalysis 4.2.1 Heterogeneous catalysts on a nanoscale order 4.2.2 Real-time observation of surface reactions . 4.3. Strongly.correlated.electron.systems 4.3.1 Overview of strongly correlated electron systems 4.3.2 Orderings of electronic degrees of freedom 4.3.3 Dynamics of skyrmion crystal 4.3.4 Electronic structure of transition metal oxide devices 4.3.5 Electronic structure at the surface and interface of magnetic thin films 4.3.6 Electron dynamics explored by resonant soft X-ray emission spectroscopy in strongly correlated electron systems 4.3.7 Dynamics in strongly correlated electron systems 4.3.8 Multiferroic materials 4.3.9 Photoinduced phase transitions 4.3.10 Electronic structure of transition metal compounds . 4.4. Materials.under.extreme.conditions 4.4.1 Overview 4.4.2 Structural characterization of materials under high pressure 4.4.3 High-pressure physics 4.4.4 High-pressure earth and planetary science . 4.5. Environmental.sciences 4.5.1 Environmental behaviors of various elements by micro-XRF-XAFS-XRD analysis 4.5.2 Understanding the formation process of dioxins by XAFS . 4.6. Life.sciences 4.6.1 Membrane proteins 4.6.2 Epigenetics i Chapter.5.Accelerator......................................................................................................................71 . 5.1. Overview . 5.2. Beam.dynamics.issues 5.2.1 Injector design and optimization 5.2.2 Lattice and optics of return loop and main linac 5.2.3 HOM BBU and heating 5.2.4 Resistive-wall wake 5.2.5 Ion trapping 5.2.6 Beam loss 5.2.7 Error tolerances . 5.3. Electron.gun 5.3.1 Introduction 5.3.2 Goals and challenges 5.3.3 Current status . 5.4. Superconducting.cavity.for.injector.linac 5.4.1 Introduction 5.4.2 Goals and challenges 5.4.3 Current status . 5.5. Superconducting.cavity.for.main.linac 5.5.1 Introduction 5.5.2 Goals and challenges 5.5.3 Current status 5.5.4 Summary . 5.6. RF.sources 5.6.1 HPRF and LLRF 5.6.2 RF configuration at the ERL and their specifications 5.6.3 Current status and future plan for the RF sources . 5.7. Cryogenics 5.7.1 Introduction 5.7.2 Current status 5.7.3 Goals and challenges . 5.8. Magnet.for.3-GeV.ERL . 5.9. Vacuum 5.9.1 Introduction 5.9.2 Goals and challenges 5.9.3 Current status . 5.10. Beam.diagnostics 5.10.1 Introduction 5.10.2 Goals and challenges 5.10.3 Current status . 5.11. Insertion.devices 5.11.1 Introduction 5.11.2 Goals and challenges 5.11.3 Current status . 5.12. XFEL.oscillator 5.12.1 Introduction 5.12.2 Goals and challenges 5.12.3 Current status Chapter.6.Beamlines.....................................................................................................................102 . 6.1. Introduction . 6.2. R&D.items.for.optical.elements 6.2.1 Monochromator crystals 6.2.2 Gratings 6.2.3 Zone plates 6.2.4 Mirrors 6.2.5 Other optical elements such as beryllium windows . 6.3. R&D.items.for.instrumentation Chapter.7.Detector.Developments...............................................................................................108 Layout of the 3GeV ERL and 6~7 GeV XFEL-O in KEK ii CONTRIBUTORS Hitoshi Abe 1, Shin-ichi Adachi 1, Kenta Amemiya 1, Taka-hisa Arima 2, Kiyotaka Asakura 3, Leonard Chavas1, Nobumasa Funamori2, Takaaki Furuya1, Ryoichi Hajima4, Kentaro Harada1, Yoshihisa Harada2, Keiichi Hirano1, Tohru Honda1, Sumio Ishihara5, Kenji Ishii4, Kaoru Iwano1, So Iwata6, Eiji Kako1, Nobuo Kamiya7, Hiroshi Kawata1, Shunji Kishimoto1, Yoshinori Kitajima1, Hisao Kobayashi8, Yukinori Kobayashi1, Hiroshi Kondoh9, Tadashi Kondo11, Shin-ya Koshihara10, Reiji Kumai1, Hiroshi Kumigashira1, Genji Kurisu11, Shinichiro Michizono1, Takashi Mizokawa2, Madoka Mochida1, Youichi Murakami1, Hirotaka Nakai1, Norio Nakamura1, Hironori Nakao1, Masaharu Nomura1, Takashi Obina1, Eiji Ohtani5, Shogo Sakanaka1, Tomoko Sato12, Norihiro Sei13, Toshiya Senda13, Yuya Shinohara2, Akio Suzuki5, Hiroki Takahashi14, Yoshio Takahashi12, Yukio Takahashi11, Masaki Takaoka6, Kimichika Tsuchiya1, Soichi Wakatsuki1, Masahiro Yamamoto1, Yuichi Yamasaki1, Junko Yano15, Wataru Yashiro5. 1KEK 2The University of Tokyo 3Hokkaido University 4JAEA 5Tohoku University 6Kyoto University 7Osaka City University 8University of Hyogo 9Keio University 10Tokyo Institute of Technology 11Osaka University 12Hiroshima University 13AIST 14Nihon University 15LBNL iii Chapter 1 Executive Summary 5 Chapter 1 Executive Summary 1.1 Introduction High Energy Accelerator Research Organization (KEK) has prepared a conceptual design report of Energy Recovery Linac (ERL) at the electron beam energy of 3 GeV (Fig. 1-1). ERL is a future X-ray light source designed based on state-of-the-art superconducting linear accelerator technology, which will offer far higher performance than the existing storage ring. The high repetition rate, short pulse, high spatial coherence and high brightness of ERL will enable the filming of ultrafast atomic-scale movies and determination of the structure of heterogeneous systems on the nano-scale. These unique capabilities of ERL will drive forward a distinct paradigm shift in X-ray science from “static and homogeneous” systems to “dynamic and heterogeneous” systems, in other words, from “time- and space-averaged” analysis to “time- and space-resolved” analysis. This paradigm shift will make it possible to directly witness how heterogeneous functional materials work in real time and space, and will enable predictions to be made in order to design and innovate bet- ter functional materials which will eventually solve the grand challenges of society and support life in fu- ture. Such functional materials will continue to be used in indispensable technologies such as catalysts, batteries, superconductors, biofuels, random access memories, spintronics devices and photoswitches. On the other hand, life itself is an intrinsically heterogeneous and dynamic system. Structural biology based on the existing storage ring technology has greatly contributed to providing the static atomic co- ordinates of proteins which are useful information for rational drug design. ERL will further contribute to biological science and biotechnology by shedding light on the heterogeneity and complexity of cellular functions. In short, ERL will be an unprecedented tool that will bridge the critical gaps in our understanding of material science and technology. More details as to why ERL is needed and how it will help solving problems of society will be presented in the following chapters. ERL is planned to be constructed in late 2010s, and expected to be operational in early 2020s. In addition, continuous improvement of linear accelerator technology will result in further quantum leaps in X-ray science in the future. One possibility is the realization of a fully coherent X-ray free-elec- tron laser. Although self-amplified spontaneous emission X-ray free-electron lasers (SASE-XFELs) have been constructed around the world, the X-ray beam from SASE-XFEL is essentially not fully coherent in the temporal domain. By configuring a Bragg diamond cavity for lasing in the X-ray region, it is proposed 3 GeV 3GeV ERL 100m Al O Al O 2 3 undulator 2 3 (00030) (00030) 143KeV X-rays λrf /2 path-length T=0.997 T=0.997T=0.997 R =0.96 R =0.92 changer 6 (7) GeV 1 1 T1=0.032 XFEL-O in 2nd stage Figure 1-1 Conceptual layout