Forelæsning 3, uge 11 Nye aceleratorer anvendelser: Et smugkig i fremtiden... AB: Nye acceleratoranvendelser Acceleratorer inden for energiteknologi Accleratorer til materialeforskning Seneste udviklinger SPM: nye acceleratorer Magneter Nye collidere Nye accelerationstrukturer Nye accelerationsprincipper
Acceleratorer inden for energiteknologi Nuclear Waste Transmutation Ide af Carlo Rubbia, foreslået i (Nobel pris i 1984 sammen med Simon van der Meer og CERN direktør i 1989-1993): Problem: Atomaffald Reducering af radiotoksicitet af affaldet Minimiring af volumen og varmebelastningen af affaldet sendt til lagring EU: 145 reactorer, 125 GWe, 850 TWh årlig produktion (35%) Årlig produktion af 2500 tons af atombrændstof i EU (25 tons Pu!) Strategi: Partitionering og Transmutation Kemisk separation af affaldet (separe Pu, MA, LLFF) Brug affaldet som brændstof i transmuter systemer Løsning: Underkritisk reaktor (k<1), med uran fri (arm) brændstof Kædereaktionen er ikke vedholdende Intens spallationskilde (høj proton flux på liquid lead target) Generer de manglende neutroner til at holde kædereaktionen i gang.
Hvad er spallation?
Underkritisk fission vha. af spallations neutroner 50 yield / E p (neutrons/gev) 40 30 20 10 0 0 0.5 1 1.5 2 2.5 proton energy, E_p (GeV)
Europæisk studie
Los Alamos studie
LINAC scheme Accelerator concepts
Acceleratorer i fusionsmaskiner
Neutralpartikel injektorer 16.5 MW neutral beam of 1 MeV D 40 A of 1 MeV D - at last grid
Andre anvendelser for spallationsneutroner Opsamling af neutroner og transport til eksperiment stationer
Hvad er neutroner godt for?
Spallation Neutron Source at Oak Ridge Nat l Lab in Tennesse, USA
SNS Oak Ridge Natl Lab The SNS accelerator system consists of a negative hydrogen (H-) radio-frequency volume source, a low-energy beam transport housing a first-stage beam chopper, a 4-vane radio-frequency quadrupole for acceleration up to 2.5 MeV, a medium-energy beam transport housing and a second-stage chopper, a 6-tank drift-tube linac up to 87 MeV, a 4-module coupled-cavity linac up to 186 MeV, and a superconducting linac with 11 medium-beta cryomodules (up to 379 MeV) and 12 high-beta cryomodules (up to 1000 MeV). The linac produces a 1-ms-long, 38-mA peak, chopped beam pulse at 60 Hz for accumulation in the ring. A high-energy beam transport line provides for diagnostics and collimation after the linac injects into a 248-mcircumference accumulator ring to compress the 1-ms pulse to ~700 ns for delivery onto the target through a ring-to-target beam transport beam line. Neutrons are produced by spallation in the target, dumping 27 kj per pulse into ~1 m3 of circulating mercury. The neutron energy is then moderated to useable levels by supercritical hydrogen and water moderators before feeding into 24 beam lines.
Spallation Neutron Source Primary Parameters Proton beam power on target 1.4 MW Proton beam kinetic energy on target 1.0 GeV Average beam current on target 1.4 ma Pulse repetition rate 60 Hz Protons per pulse on target 1.5x1014 protons Proton pulse length on target 695 ns Ion type (Front end, Linac, HEBT) H minus Front end length 7.5 m Linac length 331 m HEBT length 170 m Ring circumference 248 m RTBT length 150 m Ion type (Ring, RTBT, Target) proton Ring filling time 1.0 ms Ring revolution frequency 1.058 MHz Number of injected turns 1060 Ring filling fraction 68 % Ring extraction beam gap 250 ns Maximum uncontrolled beam loss 1 W/m Target material Hg
Sammenligning med eksiterende anlæg
ESS European spallation source
ESS site area: ESS cost Linear accelerator Linac beam energy 1 square km 1.55 Billion Euro Beam power 10 MW 1,330GeV Short Pulse target station Beam Power 5MW Pulse duration 1,4µs Repetition rate 50 Hz Number of neutron scattering instruments 22 Long Pulse target station Beam power 5MW Pulse duration 2.0ms Repetition rate 16 2/3 Hz Number of neutron scattering instruments 22 Expected number of users per year 4-5000 Expected direct and indirect jobs 2000 Staffing during operations 245 Scientists
To alternative linac strukturer
Hvor skal bygges? DK N S konsortie: Lund, Sverige?
FAIR (Facility for Antiproton and Ion Research) GSI, Darmstadt
Kerneforskning/nukleosyntese
Antiproton proton spredning
Atomfysik @ FAIR
Køreplan / budget Schedule & Costs Schedule 2007 start of project 2012 first experiments 2015 completion Costs approx. 1.2 billion Funding 65% German Federal Government 10% State of Hesse 25% international partners
X-FEL Ide: Free electron laser i det bløde Røntgen område (0.1...6.5 nm) Forsking:
TESLA-XFEL ved DESY (Hamburg)
Layout
3 XFEL beamlines + Undulator BL
Self-Amplified Spontaneous Emission (SASE)
Undulator beamlines
XFEL undulatorer
Undulatorerene
Justerbar polarisation
Accelerator Electron source
Main Linac
2 designs Beam dump
VUV FEL resultater Mætning (@λ=98 nm) 1 GW, 50 fs pulse length Shot noise forstærkning
Transversal kohærens Dobbeltspalte eksperiment Spalter: 2mmx0.2mm @ 12m bag undulator (3m fra spalter til detektor)
Linjebredde / longitudinal kohærens Antal af logitudinale modes afhænger af bunch kompressionen kort bunch lang bunch
Hvornår første XFEL beam?
Linac coherent light source LCLS: XFEL at SLAC (Stanford Linear Acclerator Center) 113 m magn. length Beam energy 14.3 GeV, peak current 3400 A, Norm ε 1.2 mm mrad RMS bunch length 77 fs
Køreplan / Budget 1999 2002 Research and Development 2003 2006 Project Engineering Design 2005 Long-Lead Procurement 2006-2008 Facilities Construction, Startup 2009 Start Operations 265M-$315M Total Project Cost, including -R&D - Design and Construction (in the range $220M - $260M, as listed above) - Startup costs - Specialized spare components for operations maintenance
Ionkilde udvikling MSc. Projekter (speciale)
HTS prototypemagnet MSc. Projekter (speciale)