Status of Projects using TESLA Cavities Mike Dykes, ASTeC, Head of RF.
Daresbury ERLP
OUTLINE Status of other Projects 4GLS Daresbury ERLP Injector Linac Cryogenics Summary
Projects Cornell ERL BESSY University of Erlangen Rossendorf
TESLA Modules Many Projects using TESLA cavities Many Projects using or modifying TESLA cryostat or Tesla cavities in new cryostat
Cornell Phase 1 E [MeV] γε [mm-mrad] Q [pc] I ave [ma] σ z [ps] f max [GHz] 100 2 @ 77 pc 1-400 100 0.1-2 1.3
Cornell Phase II
Cornell Modifications
BESSY
ERLSYN Stage 2: ERL Stage 1: Storage Ring E = 3.5 GeV ε = 1 nm C = 450 m Stage 2:
Rossendorf
Rossendorf Cryo-Module
4GLS
4GLS An XUV SASE free electron laser the XUV-FEL. A cavity-based VUV free electron laser the VUV-FEL. An integrated infra-red free electron laser the IR-FEL. Is a low energy ring; radiation from a variety of undulators. l
4GLS effectively infinite electron beam lifetime very small emittance very short pulses pulse structure flexibility www.4gls.ac.uk
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)
Why ERL Prototype? UK Skill shortage in vital areas Photo-cathode Injectors (guns) Superconducting RF Technology Esp. SRF Linacs
4GLS ERL Prototype Work is progressing in all areas for the ERLP. This talk concentrates on:- Photo-injector Gun Gun High Voltage 500kV DC supply Laser System Booster cavity RF Power Supply Superconducting linac Cryogenic Systems The work will be cross departmental and will involve ASTeC,SRD, CLF, ED, ID and HEIs.
ERLP Layout
ERLP Layout
Photo-Injector Gun Based Heavily on JLAB ERL Injector JLAB M.O.U. in place Imperial drawings 500kV DC photocathode gun GaAs Cathode choice
Photo-Injector Gun
Gun and SF6 Enclosure
Gun Pictures
500kV 8mA HT DC Supply Commercial 500kV 8mA DC Power Supply Contract placed with Glassman Europe. Power supply and gun enveloped by 0.8Bar SF6 environment
Gun HT Stack and SF6 Envelope
ERLP Photoinjector Architecture Phase stabilised fibre Phase-locked loop electronics Mirror control signal RF sensor Electrons to Linac Electron gun Booster Frequency multiplier Laser amplifier Beam conditioning Laser oscillator Controlled environment G. Hirst
Photoinjector 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: up to 10% Timing jitter: <1ps Spatial profile: circular (top hat) on photocathode G. Hirst
Booster Cavity Superconducting multi-cell cavity, boosts beam energy to 5MeV 650 MHz Freq.
Booster Cavity E-Field Mode 1 Simulation of a 600MHz 3 cell structure
RF Power Supplies
RF Power Supplies
RF Distribution
Superconducting Linac Two types under consideration. ELBE TESLA JLAB Number of cryo modules depends on individual cost Commercially available Accel Tesla cavity based
Rossendorf Cryo-Module
Superconducting Linac ELBE Type Cryostat with dual Tesla Linac Sections
Superconducting Linac ELBE TYPE
Cryogenic Refrigerator Systems
Cryogenic Refrigerator Systems Choice of Helium production method 4K and 2K systems Additional pumping reqs. Operation regime
Cryogenic Design Criteria Static Load = 3 Watts/m (24 hours/day) Dynamic Load = 45 Watts/m* (4 hours/day, 5 days/week) Temperature = 1.8-2.0 k LHe Consumption = 7000 L/week Duration of Experiment = 46 Week * Dependent on chosen E acc
Cryogenic Options Gas Recovery 2 K Refriger n 4 K Refriger n Closed Loop System Liquefier 2 K Pumping System Gas Recovery Gas feed directly into liquefier compressor Modify the Wiggler System Liquefier 2 K Pumping System Gas Recovery Gas feed directly into liquefier compressor Bulk Helium Supply 2 K Pumping System Gas Recovery Gas Bag & Bauer HP No Gas compressor Recovery Gas Recovery 2 K Refriger n 4 K Refriger n Cost A Cost B Cost C Cost D Cost E Closed Loop System Liquefier IP gas recovery Wiggler Liquefier IP gas recovery Bulk liquid HP gas recovery Bulk liquid
Cryogenic Solutions? Custom 2k Liquifier Performance Guaranteed, But expensive. 4K Liquifier, 2k sub cooler Less costly, more opportunity to enhance are skills base, But no guaranteed performance. Bulk Helium with 2k sub cooler Could be cheaper on 1 year project. Need to establish if recover is economically & Logistically viable!
Refrigeration 4k to 2K
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.
Timescales - Injector Decide cathode material 17/07/03 Decide laser λ 17/07/03 Booster designed 02/01/04 Laser commissioned 30/07/04 1 st electrons from gun 01/08/04 Booster commissioned 30/04/05 1 st electrons from booster 01/05/05
Timescales - Linac Frequency decided 17/07/03 Cryo-module decided 01/09/03 Cryogenic system ordered 02/01/04 RF power source ordered 02/01/04 Cryo-module Commissioned 31/05/05 1 st electrons accelerated 01/08/05
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 will be mainly made in house. Specialist components/services sourced from JLAB. 500kV power supply contract running. Decisions on Linac type needed soon! Decision on cryo systems needed soon!