4GLS and the Daresbury ERL Prototype. Mike Dykes, ASTeC, Head of RF.

Transcription

1 4GLS and the Daresbury ERL Prototype Mike Dykes, ASTeC, Head of RF.

2 OUTLINE 4GLS Daresbury ERL Prototype Gun Buncher & Booster Linac Cryogenics Controls Project Milestones Summary

3 THE SHAPE OF THINGS TO COME...

4 4GLS

5 4GLS Management SRO John Wood ERL Prototype Project Board Hywel Price (Chair and Project Sponsor), Elaine Seddon, Mike Poole, Mike Chesters, Henry Hutchinson, Pat Ridley, Wendy Flavell, Peter Weightman 4GLS Project Manager - Elaine Seddon ERL Prototype Management Group - chair Elaine Seddon ERL Prototype Technical Team - chair Susan Smith Gateway Group Start-to-end Design Controls Susan Smith Brian Martlew Gun SC RF Linac and Mike Dykes cryogenics Mike Dykes Synchronisation High Gain FELs Graeme Hirst Brian McNeil Electrical Engineering Steve Griffiths Vacuum Ron Reid Mechanical Engineering Neil Bliss Diagnostics Rob Smith Magnets Neil Marks Oscillator FELs and IDs Jim Clarke Beamlines and Experimental Systems Frances Quinn Health, Safety and Environmental Martin Holbourne Exploitation Group Regional Dimension Group 4GLS Design Group All activities supported by the Project Planning and Resources Group

6 4GLS IAC: Membership Prof Dr Gerd Materlik CEO, DLS Prof Ilan Ben Zvi BNL, USA Dr Paul Dumas LURE, France Dr George Neil JLAB, USA Prof Ingolf Lindau MAXLAB, Sweden Dr Jean-Michel Ortega LURE, France Prof Dr Uwe Becker Germany Prof John Sutherland BNL, USA Dr Carlo J. Bocchetta ELETTRA, Italy Dr Mikael Eriksson, MAXLAB, Sweden Prof Hasan Padamsee Cornell University, USA Prof Gennady Kulipanov BINP, Russia Prof Giorgio Margaritondo Lausanne, Switzerland Prof Peter Lindley Portugal Prof Francois Wuilleumier LSAI, Universite Paris-Sud Dr Albert Parr NIST, USA

7 4GLS IAC: remit To advise the project team on all aspects of the 4GLS project including strategic directions for the future.

8 RCUK Strategy Group Approved funding for the research, development and design phase of the 4GLS project. This funding has a three year timescale and the specific recommendations are: 1. to focus on the research and development work needed for the design and exploitation of the facility; 2. to establish an ERL prototype test facility; 3. to undertake detailed design studies leading to a technical Design Report (TDR); and 4. to proceed with Gateway preparations

9 Technical Priorities 1. Demonstrate energy recovery 2. Operate a superconducting linac 3. Produce and maintain bright electron bunches from a photo-gun 4. Produce short electron bunches from a compressor 5. Demonstrate energy recovery with an insertion device that significantly disrupts the electron beam 6. Have an FEL activity that is suitable for the synchronisation and seeding needs 7. Produce simultaneous photon pulses from a laser and a photon source of the ERL Prototype that are synchronised at or below the 1ps level

10 International Collaborations

11 ERLP Layout

12 ERLP Parameters ERL Prototype Actual Values ( 35 MeV ) Parameter Single Bunch Short Pulse Long Pulse CW Beam Gun to Booster Energy 500 kev 500 kev 500 kev 500 kev Injector Energy ~ 5 MeV ~ 5 MeV ~ 5 MeV ~ 5 MeV Beam Energy 35 MeV 35 MeV 35 MeV 35 MeV Linac RF Frequency 1.3 GHz 1.3 GHz 1.3 GHz 1.3 GHz Average Current (ma) Peak Current (ma) Bunch Length (RMS) at FEL ~ 0.6 ps ~ 0.6 ps ~ 0.6 ps ~ 0.6 ps Relative Energy Spread at FEL 0.2 % 0.2 % 0.2 % 0.2 % Bunch Length (FWHM) at U ps 0.5 ps 0.5 ps 0.5 ps Bunch Spacing (ns) Bunch Repetition Rate (MHz) Bunches per Train Train Length (ms) Train Spacing (ms) Train Repetition Rate (Hz) Duty Factor 1/ Max Bunch Charge (pc) Average Power at 35 MeV (kw) Average Power at 5 MeV (kw)

13 ERLP Shielding 13.9 W 1m concrete + 10 cm lead µsvh -1 gamma dominated µsvh -1 neutron dominated 13.9 W 2m concrete µsvh -1 gamma dominated µsvh W 2m concrete + 15 cm steel µsvh -1 gamma dominated µsvh -1

14 ERLP Layout

15 GUN

16 Photo-Injector Gun Based Heavily on JLAB ERL Injector JLAB M.O.U. in place Imperial drawings 500kV DC photo-cathode gun GaAs Cathode choice

17 Photo-Injector Gun

18 Jlab Gun

19 Gun Pictures

20 Cathode Ball & Stem Cathode ball Cathode stem

21 Gun Power Supply Commercial 500kV 8mA DC Power Supply Contract placed with Glassman Europe. Power supply and gun enveloped by 0.8Bar SF6 environment

22 Gun Stack and SF6 Tank

23 Laser Parameters Wavelength: 1.05µm, multiplied to 0.53µm/0.26µm Pulse energy: 40nJ on target Pulse duration: 10ps FWHM Pulse repetition rate: 160 MHz Macropulse duration: >100µs Duty cycle: 0.2% Timing jitter: <1ps Spatial profile: circular (top hat) on photocathode

24 Buncher& Booster

25 Buncher & Booster Cavity Buncher cavity Normal conducting cavity, bunch length compression 650 MHZ or 1.3 GHz Based on EU Hom damped cavity Booster cavity Superconducting multi-cell cavity, boosts beam energy to ~ 5MeV 1.3 GHz

26 Superconducting Linac ELBE TESLA Number of cryo modules depends on individual cost Commercially available Accel Tesla cavity based

27 Rossendorf Cryo- Module

28 Superconducting Linac ELBE Type Cryostat with dual Tesla Linac Sections

29 Superconducting Linac ELBE TYPE

30 Cryogenic Design Criteria Static Load = 12 Watts/m (24 hours/day) Dynamic Load = 100 Watts* (4 hours/day, 5 days/week) Temperature = k LHe Consumption = 7000 L/week Duration of Experiment = 46 Week * Dependent on chosen E acc

31 Cryogenic Options Gas Re covery 2 K Refriger n 4 K Refriger n Closed Loop System Liquefier 2 K Pumping System Gas Re covery Gas fe ed directly into liquefier compres sor Modify the Wiggler System Liquefier 2 K Pumping System Gas Re covery Gas fe ed directly into liquefier compres sor Bulk Helium Supply 2 K Pumping System Gas Re covery Gas Bag & Bauer HP No Gas compres sor Recove ry Gas Re covery 2 K Refriger n 4 K Refriger n Cost A Cost B Cost C Cost D Cost E Closed Loop System Liquefier IP gas re covery Wiggler Liquefier IP gas re covery Bulk liquid HP gas recovery Bulk liquid

32 Refrigeration 4k to 2K

33 ERLP Control System Provides remote monitoring and control of all important sub-systems (Injector, Linac, Vacuum etc) Distributed system with Input/Output Controllers (IOCs) connected to client consoles via Ethernet Uses the EPICS control system toolkit IOCs will use VME + PPC + VxWorks Clients will use Linux and standard EPICS tools Initial estimates show approx. 10 IOCs controlling about 5000 I/O signals.

34 Milestones 1. Operation of the photoinjector. 80 pc in 35 ps for a 100 µs macropulse. Date Operation of superconducting booster. Date Demonstrate electron/rf synchronisation. To sub-ps level. Date Linac modules and refrigeration. 2K operation with first beam and an energy gain of 30 MeV. Date

35 Milestones (cont) 5. Beam around the whole system without insertion devices and without energy recovery. Date Bunch compression. Date Energy recovery without insertion devices. Date Energy recovery with insertion devices. Date

36 Conclusions Work is now progressing in several technical areas. Gun will be based on JLAB gun. MOU means DL has access to all JLAB gun drawings, and expertise. Production of components has started, and will be mainly made in house. Specialist components/services sourced from JLAB. 500kV power supply contract running. Linac probably ELBE type, needs to be ordered soon! Cryo systems out to tender

37 Contributions This talk was prepared with help from:- Bob. Bate (ASTeC Cryogenics) Carl Beard (ASTeC RF) Steve Bennett (SRD, Gun Development) Neil Bliss (Eng. Dept) Kal. Fayz (Eng. Dept) Fay Hannon (ASTeC Gun development) Graeme Hirst (Central Laser Facility) Andy Goulden (SRD Cryogenics) Steve Griffiths (SRD Elec. Eng.) Rachael Jones (SRD Cryogenics) Charles Monroe (Monroe Brothers) Andy Moss (ASTeC RF) Rob. Smith (ASTeC Gun Development) Brian Todd (Eng. Dept)