BU

D. Ang

Abstract The MAX

top up into injector for aphase 2) [1achromats wmomentum ctogether withphase space.the achromattracking thromode.

The MAXand construcenergy linac will be opersingle pass sps x-ray puldrive both inproduce highrelaxed demdemands a buresults, preseare easily obtwo of the Mable to prodSuch results

TThe same

to drive bothFERMI gun linac sectionof a 35 MW power will b

UNCH CO

Sgal-Kalinin

X IV linac willtwo storage ra Short Pulse1]. Compress

with positive Rcompaction, Th weak sextu In this procet compressorsough the MAX

MX IV project [2

tion has starteand a Short

rated at 1.5 aspontaneous lilses. The injenjection and toh brightness p

mands on emiunch length bented later in tbtained with tMAX IV projduce low emihave also bee

THE MAXphoto cathod

h ring injectio[3]. The acc

ns together wiklystron and

be doubled wi

OMPRES

S. Thorin, MJ. McKenz

l be used bothrings, and as

e Facility (SPFsion is doneR56. The nat

T566, from theupoles to lineeeding we pres and initial reX IV Injector

MAX IV 2] at MAX-labed to build 2 sPulse Facility

and 3 GeV. Tinac lightsourctor will be fop-up for the

pulses for the ittance ( < 1elow 100 fs Fthis paper, shothe MAX IV ect, the injecttance pulses

en produced in

X IV INJECde RF electronon and SPF. Iceleration is dith 15 RF unia solid state mith a SLED. T

Figure 1:

SSION BYTHE MA

M. Eriksson,zie, B. Milit

h for injectiona high brigh

F) and an FEe in two dotural second e achromats isearise longituesent the desiesults from pain high brigh

b has been funstorage rings, y (SPF). The The SPF will rce, producingflexible enoustorage ringsSPF. The SPF0 mm mrad)

FWHM. Simulow that such p

injector. In pctor should als

to drive an n simulations.

CTOR n gun will be It is a copy odone in 39 S-its, each consimodulator. ThThe repetition

Schematic ov

Y LINEAAX IV INJ

S. Werin Msyn, P. Will

n and htness EL (in ouble order

s used udinal gn of

article htness

nded, a full rings be a

g sub-gh to s, and F has ) and lation pulses phase so be FEL.

used of the -band isting he RF n rate

of thrings Gen Thewithquadinjeccompapprsche

DouLine

Tcompunliknegaof thnaturlineachoooptimlinac

A dispepositcouldsextu

ThoversextuT566full sextu

verall layout o

ARISING AJECTOR

MAX-lab, Lliams, STFC

he injector is s will be at 10

neral Layou lattice in the

h focusing qdrupole, and ction into thpression is

roximately 26matic view of

uble Achromearisation The magneticpressors in thke the commoative R56. Wehe RF voltagrally have a parising effect ose the opticmal linearisatic for this purp

sextupole is ersion at the tioned at the d be compareupoles in a stohe natural T5r-linearising upoles work i6, to compens

linearisationupole strength

of the MAX IV

ACHROMR

Lund, SwedeC/DL/ASTe

100 Hz, but t0 Hz.

ut e main linac iquadrupole, l

linac. The he rings at

done in 60 MeV and af the layout ca

mat Compre

c double ache MAX IV inonly used mage have thus toge. Both typpositive T566

in the achral parametersion without nose. needed to mend of the achromat m

ed with the corage ring. 66 of the douthe RF indin the opposi

sate for the ovn of longituh has to be i

V Injector.

MATS FO

en eC, Daresbu

top up and inj

is done as a Flinac sectionbeam is kic1.5 and 3

double acat full energyan be seen in F

ession and

chromats usenjector has a gnetic chicaneo work on thepes of bunch

and a positivromat case. Ws in the ach

needing to hav

minimize the achromat. Th

middle, is rathchromaticity c

uble achromaduced curvatuite direction oer-linearisatio

udinal phase increased [4].

OR

ury, UK

njection to the

FODO latticen, defocusingcked out forGeV. Bunch

chromats aty, 3.6 GeV. AFigure 1.

ed as bunchpositive R56

e which has ae falling slope

compressorsve T566 has aWe can thus

hromat to getve a harmonic

second orderhis sextupole,her weak andcompensating

ats is actuallyure and theof the naturalon. To achieve

space, the This can be

e

e g r h t

A

h 6 a e s a s t c

r ,

d g

y e l e e e

Proceedings of FEL2010, Malmö, Sweden WEPB34

FEL technology I: Injector and Linac 471

done in suchclosed at thedispersion beFor a spontana problem. Bsatisfying linemittance pu

One singlsecond-orderThe relevant angle or posithe achromatthese terms. the beam insconstruction Since the R5crest RF phaSchematic vachromat buFigure 5. CoBC’s for theand for the F

Figu

Figu

h a way that e end of the Becomes large,neous source

But even withonearisation ca

ulses, althoughle achromat r effects actinones are ener

ition. The intrts bending in We will also

stead of a chof the linac h

56 of the douase is used t

views, dispersunch compressmpression and

e SPF optimisFEL optimisati

ure 2: Layout

ure 3: Layout

second orderBC, but the en leading to inlike the SPF t

out over-tuninan be achieveh at a lower pe

will also inng in the trargy-dependentroduction of aopposite dire

o effectively gange of angleall.

uble achromato vary the cosion and optsors can be sd linearisationsation are preion in Table 2

of bunch com

of bunch com

r dispersion snergy derivatincreased emittthis is howeve

ng the sextupoed to produceeak current. nduce some ansverse direct and thus linea double achroections, will cget a translatioe, which ease

ts is fixed, thompression faics of the doeen in Figuren parameters oesented in Ta2.

mpressor 1.

mpressor 2.

till is ive of tance. er not oles, a e low

other ction. ear in omat,

cancel on of es the

he off factor. ouble

e 2 to of the able 1

Fig

Fig

Tablhigh

R

T

E

L

Is

gure 4: Optics

gure 5: Optics

e 1: Compresh peak current

R56

T566

Energy

Linac phase

Integrated sexstrength

and dispersio

and dispersio

sion and lineaoptimisation

BC1

3.23

9.26

275 M

32○

xtupole ± 10

on in bunch co

on in bunch co

arisation param

BC2

cm 2.6 cm

cm -17.8

MeV 3700 M

17.5○

m-2 ± 10 m

ompressor 1.

ompressor 2.

meters in the

m

cm

MeV

m-2

WEPB34 Proceedings of FEL2010, Malmö, Sweden

472 FEL technology I: Injector and Linac

Table 2: Comlow emittanc

R56

T566

Energy

Linac pha

Integratestrength

BEAMA realistic ASTRA [5] first linac moread into Elethe bunch clongitudinal longitudinal radiation. Befound in Tab

Figur

mpression andce optimisation

ase

ed sextupole

M DYNAMbunch distr

to optimise podule L0. Theegant [6] for compressors.

wakefields space charg

eam parametele 3.

re 6: Simulatio

d linearisationn BC1 B

3.23 cm 2

33 cm 8

275 MeV 3

32○

± 5 m-2 ±

MICS SIMUribution was parameters upe bunch was ttracking throThe effects

were incge and coh

ers after the el

on results for t

n parameters i

BC2

2.6 cm

8.5 cm

3700 MeV

15.5○

± 4 m-2

ULATIONSgenerated

p to the end othen convertedough the linacof transverse

cluded, as erent synchrlectron gun ca

the high peak

in the

S using

of the d and c and e and

was rotron an be

Tamo

E

Δ

N

Hig Selongset uemitshowcomplineais acand the erespeemitaccebelow

current optim

able 3: Beam podule Energy

ΔE/E

Norm. emittan

gh Peak Curxtupoles in itudinal phasup is optima

ttance degradaws the propertpressor. It arisation is effchieved. This slice emittaneffect of shifect leading ttance value optable numbew 10 mm mra

misation for the

parameters aft

105 M

1.5 %

nce 0.4 m

rrent Optimithe achromae space curval for the shation is not oies of the buncan be seen

ffective and this done at thece. Coherent

fting trailing pparticles, givof 2.5 mm m

er for the SPF,ad.

e SPF.

fter the gun an

MeV

% (FW)

mm mrad

isation ats were tuneature was mihort pulse faof great concnch at the exit n that comphat a peak cure expense of b

synchrotron particles tranving the finmrad. This is, which needs

d first linac

ed such thatinimised, thisacility whereern. Figure 6of the second

pression andrrent of 20kAboth projectedradiation hassversely withal horizontals still a verys an emittance

t s e 6 d d A d s h l y e

Proceedings of FEL2010, Malmö, Sweden WEPB34

FEL technology I: Injector and Linac 473

Low Emitta In order toelectron lasedegradation tuning the sethe chromaderivative olongitudinal not comprecurrent again7 shows thcompressor 2well preservstudies at sisufficient to

Outlook

In order compressors disturbing thsextupole famexamined bcompressors

ance Optimo provide a ber we must as much as p

extupoles in batic amplitudf dispersion, linearisation ss as aggresnst final projehe bunch pro2. We see thaved. The peakimilar facilitiedrive an FEL.

to make more flex

he energy dermily could bebefore the is decided.

Figure 7: Sim

misation bunch suitablsuppress tra

practicable. Thbunch comprede functions

in exchangeof the bunch. ssively, therected and slice

operties at that the bunch sk current is es suggest th.

the double xible to tunrivative of die added. This final design

mulation resu

le to drive a ansverse emithis is achievessor 2 to min

s and chrome for relaxing

In addition weby trading e emittance. Fhe exit of bslice propertiereduced, how

hat 3kA woul

achromat bne T566 wiispersion, an possibility w

n of the b

lts from the lo

free-ttance ed by imise matic g the we do

peak Figure bunch es are wever ld be

bunch ithout extra

will be bunch

MdriveextrachanR56

[1]

[2]

[3][4]

[5]

[6]

[7]

ow emittance

Many options ter are availaba linac sectionnging the sec

chicane. Mor

S. Werin et aPhysics ReseaMAX IV cohttp://www.mMAX-IV-CDM. Trovò et aR. J. Englandlongitudinal tdispersionlessSpecial TopicK. Flöttman. Awww.desy.deM. Borland. ECode for Acc(2000). S. werin et alRay FEL Driv

optimisation. to use the MAble. Examplens to reach higcond bunch cre about this c

REFEREal., Nuclear Inarch A 601 (2onceptual des

maxlab.lu.se/mDR.pdf. al., EPAC 08, d et al., “Sextutransport of res translating scs-AcceleratorASTRA User

e/$\sim$mpyflElegant: A flexcelerator Simu

., “The MAX ver.” WEPA1

AX IV Injectes of upgradegher electron compressor foan be found h

NCES nstruments an2009) 98–107.sign report (

maxlab/publica

MOPC080. upole correctioelativistic beamections.” Phyrs And Beamsr Manual (200lo. xible SDDS-C

ulation. APS L

IV Injector as1, These proc

or as an FELes are addingenergies, and

or a negativehere [7].

nd Methods in (2006). URLations/max4/

on of the ms in sical Review s 8 (2005). 00). URL

Compliant LS-287

s a Soft X-ceedings.

L g d e

n

L

WEPB34 Proceedings of FEL2010, Malmö, Sweden

474 FEL technology I: Injector and Linac