1

Sta

tus

of

the

Cav

ity B

PM

Dev

elopm

ents

at K

NU

and F

erm

ilab

Seu

nghw

an S

hin

KN

U /

Fer

mil

ab

17,

Mar

ch,

2009

2

Agen

da •

Intr

oduct

ion.

•C

avit

y B

PM

R&

D f

or

ILC

BD

S a

t K

NU

.

•C

avit

y B

PM

R&

D f

or

ILC

ML

at

Fer

mil

ab.

•R

emote

mac

hin

e st

udy f

or

futu

re w

ork

.

•S

um

mar

y.

3

Intr

oduct

ion /

The

requir

emen

t fo

r hig

h r

esolu

tion B

PM

.

Rea

liza

tion

of

a pre

cise

bea

m h

andli

ng

is

stro

ng

ly r

equir

ed i

n f

utu

re

acce

lera

tors

such

as

lin

ear

coll

ider

s (L

C)

and X

-ray

fre

e el

ectr

on l

aser

s (X

FE

L).

It g

oes

wit

hou

t sa

yin

g t

hat

a h

igh

res

olu

tio

n b

eam

posi

tion

mea

sure

men

t is

th

e k

ey.

Sch

emat

ic l

ayou

t of

the

ILC

co

mp

lex

ML

:

L-B

and

cav

ity B

PM

2×2

80

(~

0.5

-2 µ

m)

BD

S:

C-B

and c

avit

y B

PM

S-B

and

cav

ity B

PM

14 (

< 0

.1-0

.5 µ

m)

Fer

mil

abK

NU

Hig

h l

um

inosi

ty

Sm

all

bea

m s

ize

(~ n

m l

evel

)P

reci

se o

rbit

contr

ol

( ~

nm

res

olu

tion)

4

Intr

oduct

ion /

Ele

ctro

de

BP

M

Stripline BPM in ATF .

“Wall Current”σ ∼

1/γ

1

2

3

4

1.

Lar

ge

ther

mal

nois

e due

to w

ide

ban

d w

idth

.

2.

Zer

o p

osi

tion a

lso p

roduce

the

larg

e si

gnal

for

each

ele

ctro

de.

3.

Sin

ce t

he

signal

s of

elec

trode

are

read

out

indep

enden

tly,

reso

luti

on i

s li

mit

ed b

y A

DC

bit

count.

(To d

irec

tly

subtr

act

anal

og s

ignal

s)

r <

< R

5

Intr

oduct

ion /

Cav

ity B

PM

Pri

nci

ple

Dip

ole

mo

de

~ q

·δx

Mo

no

ple

mo

de

~ q

Gen

erat

es d

ipole

(T

M110)

and m

onopole

(T

M010)

modes

Nee

ds

monopole

mode(

TM

110)

suppre

ssio

n!

Dip

ole

mode

sele

ctab

le c

ouple

r

1.

Sm

all

ther

mal

nois

e due

to n

arro

w b

and w

idth

(~

MH

z).

2.

No s

ignal

at

zero

posi

tion.

3.

Posi

tion i

s ca

lcula

ted w

ith t

he

dip

ole

mode

of

cavit

y p

ickup

4.

Norm

aliz

atio

n f

rom

dif

fere

nt

signal

(m

onopole

mode)

.

6

Intr

oduct

ion /

Cav

ity B

PM

PUω

≡L

Qw

all

0Q

P

Uω

≡o

ut

ext

QP

Uω

≡

Vo

ut

tim

e

Vo

ut

0

2τ

2π

/ω

Uω

2V

R/Q

W

her

e=

∫⋅

=

EV

zd

)R

/Q(

Q2

Vex

t

0

Zq

ZPout

out

ω=

=

)si

n(

VV

20

φω

τ+

=−

te

t

out

out BW

Tkb

⋅=

4V

Th

ext

QQ

11

Q11

0L

+=

≡ω

τ

Par

amet

ers

for

cavit

y B

PM

S:

N:

~δx

Pout

7

KN

U a

ctiv

itie

s /

KN

U i

ntr

oduct

ion

KNU

Science Hall 1

College of Engineering Bldg. 3

College of Engineering Bldg. 10

Techno Park

Cavity B

PM

desig

n

Cavity B

PM

Fabri

cation

Ele

ctr

onic

s d

esig

n

Ele

ctr

onic

s F

abrication

RF

measure

men

t

Seo

ul

PA

LK

NU

Th

e C

entr

e fo

r H

igh

-En

erg

y P

hysi

cs i

n K

ore

a w

as f

orm

ally

in

aug

ura

ted

at

KN

U.

Sep

tem

ber

2000

:

Mar

ch 2

006

: A

ccel

erat

or

rese

arch

was

sta

rted

.

Sep

tem

ber

2006

: C

avit

y B

PM

R&

Ds

for

ILC

was

sta

rted

.

8

AT

F &

AT

F2 (

KE

K)

Wh

y A

TF

?

=>

Worl

d’s

low

est

emit

tan

ce b

eam

.

Wh

at’s

AT

F2 f

or

?

=>

Fo

cusi

ng t

he

bea

ms

to n

m s

ize.

=>

Pro

vid

ing

su

b n

m s

tab

ilit

y.

T. T

auch

i, A

TF

2 m

eeti

ng,

May

2008

KN

U a

ctiv

itie

s /

AT

F i

ntr

oduct

ion

9

KN

U a

ctiv

itie

s /

KE

K I

P-B

PM

8.7

nm

po

siti

on

re

solu

tio

n!

1. N

arr

ow

gap to

be insensitiv

e to the b

ea

m a

ngle

.

2. S

mall

apert

ure

(bea

m t

ube)

to k

eep the s

ensitiv

ity.

3. S

epara

tion o

f x a

nd

y s

ignal. (

Recta

ngula

r cavity)

4. D

ouble

sta

ge h

om

od

yne d

ow

n c

onvert

or.

Port

f (GHz)

β βββQ0

Qext

X5.712

1.4

5300

3901

Y6.426

24900

2442

Desig

n p

ara

mete

r

Model

intr

oduct

ion

Ele

ctro

nic

s

Char

acte

rist

ics

Res

ult

s

Ne

ed

to

be

im

pro

ve

d t

o 2

nm

!

10

KN

U a

ctiv

itie

s /

KN

U l

ow

-Q I

P-B

PM

Char

acte

rist

ics

1. S

am

e b

asic

id

ea w

ith

KE

K I

P-B

PM

.

2. S

ho

rt d

ecay

tim

e 2

0 n

s fo

r x

an

d y

sig

nal

s.

3. S

ho

rt d

ecay

tim

e 3

0 n

s fo

r re

fere

nce

sig

nal

.

4. S

ing

le s

tag

e h

om

od

yn

e d

ow

n c

onv

erto

r.

5. L

.O. si

gn

al f

rom

ref

eren

ce c

avit

y.

Des

ign

par

am

eter

Port

f (G

Hz)

βQ

0Q

ext

X5.7

12

85900

730

Y6.4

26

96020

670

Ref

eren

ce6.4

26

0.0

117

1170

100250

ext

QQ

11

)1

(Q1

0L

+=

=ω

τ

Sm

all

val

ue

in r

efer

ence

cav

ity

Sm

all

val

ue

in s

enso

r ca

vit

y

Dev

elopm

ent

Oth

er s

ign

al c

on

tam

inat

ion

Lar

ger

co

up

lin

g s

lot

Purp

ose

Kick

erBP

M

Sign

al fe

edba

ck

Kick

erBP

M

Sign

al fe

edba

ck

150 n

s

11

KN

U a

ctiv

itie

s /

KN

U l

ow

-Q I

P-B

PM

Bas

ic b

eam

tes

t

Res

ult

s

-600

-400

-20

00

20

040

06

00

0

50

100

150

200

250

Voltage at the scope

(normalized to 10^10 electrons/bunch)

[mV ]

Beam

positio

n a

t th

e c

avity [

µm]

KE

K I

P-B

PM

Low

-Q I

P-B

PM

Expec

tati

on l

ine

of

low

-Q I

P-B

PM

Y s

ignal

x y

inte

nsi

ty

)R

/Q(

Q2

Vex

t

0

Zq

out

ω=

~δx

x y

15

0 n

s

12

KN

U a

ctiv

itie

s /

KN

U l

ow

-Q I

P-B

PM

Ele

ctro

nic

s des

ign

BP

F

Lim

iter

DA

Phase

shifte

r

Pow

er

div

ider

Dete

cto

r LP

F

LP

F

Hyb

rid

Couple

rB

PF

Rin

g

Couple

rM

ixe

r

LN

AD

A

LN

AD

A

LO

IF(I)

RF

RF

IF(Q)

Detection

Voltage

10 d

Bm

-3 d

B7 d

Bm

-3 d

B4 d

Bm

-1 d

B3 d

Bm

-3 d

B0 d

Bm

10 d

B10 d

Bm

10 d

Bm

-30 d

Bm

26 d

B-4

dB

m0 d

B-4

dB

m-3

dB

-7 d

Bm

-3 d

B-1

0 d

Bm

-8 d

B-1

8 d

Bm

-3 d

B-2

1 d

Bm

-21 d

Bm

26 d

B-4

dB

m

Pre

lim

inar

y f

eedbac

k t

est

by K

EK

Low

-Q c

avit

y B

PM

R&

D w

ill

be

conti

nued

….

13

KN

U a

ctiv

itie

s /

S-b

and B

PM

(K

NU

/LA

PP

/RH

UL

/KE

K)

1. S

ub

mic

ron

res

olu

tio

n f

or

BB

A w

ith

1 µ

m.

2. A

few

mm

dyn

amic

ran

ge.

3. 4

0 m

m d

iam

eter

bea

m t

ub

e.

4. 2

2 M

Hz

do

wn

-co

nv

erte

d f

req

uen

cy.

Port

f (G

Hz)

βQ

0Q

ext

X2.8

78

2.5

6000

2400

Y2.8

78

2.5

6000

2400

Des

ign

par

am

eter

Model

intr

oduct

ion

Char

acte

rist

ics

Fab

rica

tion &

RF

tes

tIn

stal

lati

on a

t A

TF

2

14

Fer

mil

ab a

ctiv

itie

s /

Over

vie

w

Tes

t fa

cili

ty

=>

Tes

ting s

up

erco

nduct

ing a

ccel

erat

ing

module

s w

ith a

bea

m s

truct

ure

sim

ilar

to b

oth

Pro

ject

-X a

nd I

LC

.

NM

L f

or

ILC

and P

roje

ct-X

FN

AL

cav

ity B

PM

for

ILC

ML

(F

abri

cati

on)

FN

AL

cav

ity

BP

M f

or

NM

L (

Des

ign)

Inje

cto

r

ILC M

odule 1

(DESY “kit”)

dog-l

eg t

est

bea

m-l

ine

(TB

D)

hig

h e

ner

gy b

eam

-

lines

ILC M

odule 2

(Made in USA)

Peo

ple

: M

. W

end

t /

A.

Lu

nin

/ G

. R

em

ano

v /

N. S

oly

ak /

L. V

aler

io /

I. G

oin

i /

S.

Sh

in

15

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

ILC

ML

Bea

m p

aram

eter

s, e

.g.

–B

un

ch-t

o-b

un

ch s

pac

ing

∆t b

≈37

0 n

s (I

LC

)

–N

om

inal

bun

ch c

har

ge

= 3

.2 n

C

Bea

m d

ynam

ic r

equir

emen

ts

–<

1 µ

m r

eso

luti

on

, si

ng

le b

unch

fo

r IL

C

–A

bso

lute

acc

ura

cy <

300

µm

–S

uff

icie

nt

dyn

amic

ran

ge

Cry

om

od

ule

quad

/BP

M p

ackag

e

–L

imit

ed r

eal

esta

te, 7

8 m

m b

eam

pip

e d

iam

eter

!

–O

per

atio

n a

t cr

yo

gen

ic t

emp

erat

ure

s (2

-10

K)

–C

lean

-ro

om

cla

ss 1

00 a

nd

UH

V c

erti

fica

tion

16

Fer

mil

ab a

ctiv

itie

s /

FN

AL

cold

cav

ity B

PM

for

ILC

Frequency, GHz, dipole

monopole

1.468

1.125

Loaded Q (

both

monopole

and d

ipole)

~ 600

Beam pipe radius, mm

39

Cell radius, mm

113

Cell gap, mm

15

Waveguide, mm

122x110x25

Coupling slot, mm

51x4x3

Win

do

w –

Cera

mic

bri

ck o

f alu

min

a 9

6%

ε r=

9.4

Siz

e:

51

x4

x3 m

m

N t

ype

recepta

cle

s,

50 O

hm

17

Fer

mil

ab a

ctiv

itie

s /

FN

AL

cold

cav

ity B

PM

for

ILC

Des

ign

Fab

rica

tion

Low

tem

per

ature

UH

V t

ests

Bra

zing

(Tw

o h

alves

& c

eram

ic w

indow

s)

Wav

eguid

e fi

t

Bra

zing (

Wav

eguid

e)

Sta

tus

It s

hould

be

modif

ied f

or

Pro

ject

-X a

s w

ell

as I

LC

1.3

GH

z! C

om

pac

t! I

nte

nsi

ty s

ignal

fro

m S

C c

avit

y!

18

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

ILC

-lik

e P

roje

ct X

-lik

e

19

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

Des

igned

model

.

Char

acte

rist

ics

of

des

igned

model

.

23

0 m

m

78

mm

14

mm

Pil

l box c

avit

y w

ith b

eam

tube.

R

ecta

ngula

r ca

vit

y w

ith b

eam

tube.

But

no m

ode

(lea

kag

e to

bea

m t

ube)

.

Com

bin

ed m

odel

is

clea

nab

le.

Des

ign c

avit

y B

PM

consi

sts

of

cyli

ndri

cal

and r

ecta

ngula

r ca

vit

ies.

Cy

lindri

cal

cavit

y h

ave

eigen

modes

incl

udin

g d

ipole

mode.

But

rect

angula

r ca

vit

y h

ave

no e

igen

mode

due

to l

arge

bea

m t

ub

e.

Boundar

ies

bet

wee

n b

oth

cav

itie

s an

d b

etw

een c

avit

y a

nd b

eam

tub

e ar

e

op

en.

It m

akes

cav

ity

BP

M t

o b

e cl

eanab

le.

Dip

ole

mode

in c

yli

ndri

cal

cavit

y e

asil

y l

eakag

e in

to r

ecta

ngula

r ca

vit

y.

But

monop

ole

mode

does

n’t

.

20

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

Intr

oduct

ion t

o m

odel

.

Eig

en m

ode

clas

sifi

cati

on.

1.1

2.1

1.5

Mo

no

po

le

Dip

ole

Qu

ad

rup

ole

1.1

2.1

1.3

Mo

no

po

le

Dip

ole

Qu

ad

rup

ole

1.4

Q

ua

dru

po

le

1.7

1

.72

D

ipo

le-l

ike

Qu

ad

rup

ole

-lik

e

Fre

qu

en

cy (

GH

z)F

req

ue

ncy

(G

Hz)

Re

cta

ng

ula

r ca

vit

y

len

gth

(m

m)

60

3

0

0

Re

cta

ng

ula

r ca

vit

y l

en

gth

Be

cau

se i

t is

so

clo

se t

o d

ipo

le,

the

sig

na

l o

f th

is m

od

e s

ho

uld

be

ca

lcu

late

d i

n d

eta

il.

21

1.0

1.2

1.4

1.6

1.8

2.0

1E

-4

1E

-3

0.0

1

0.1

Sqrt(1/Qext)

Fre

qu

ency (

GH

z)

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

10

4

10

5

10

6

10

7

10

8

(60,4

0)

(75,5

0)

Qext

Position (x mm,z mm)

(45,3

0)

73

74

75

76

77

48

49

50

51

52

z (mm)

x (mm)

631.0

675.4

719.8

764.1

808.5

852.9

897.3

941.6

986.0

Coupli

ng a

long p

osi

tion.

)R

/Q(

Q2

Vex

t

0

Zq

out

ω=

-3.5

-3.0

-2.5

-2.0

-1.5

400

500

600

700

800

900

Qext

Depth (mm)

Mo

no

po

le m

od

eD

ipo

le m

od

e

∆Q

ext:

4 %

fo

r 1

00

µm

∆

Qex

t: 0

.7 %

fo

r 1

00

µm

22

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

0.0

0.5

1.0

1.5

2.0

2.5

3.0

0.0

0.1

0.2

0.3

0.4

0.5

Dipole mode

Quad. (route 1)

Quad. (route 2)

Sqrt(R/Q) [sqrt(ΩΩΩΩ)]

Offset (mm)

route

1

route

2

(1 m

m o

ffset)

Dip

ole

mode

Quad

. m

ode

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.0

0.1

0.2

0.3

0.4

0.5

Sqrt(R/Q) [Sqrt(ΩΩΩΩ)]

Angle (rad)

Cav

ity

Rec

tan

gu

lar

stru

ctu

re

Bea

m

)R

/Q(

Q2

Vex

t

0

Zq

out

ω=

Norm

aliz

ed s

hunt

imped

ance

. angle

quadrupole

monopole

position

out

VV

VV

V0

++

+=

~δx

0.4

4 µ

m /

µra

d

23

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

0.0

0.5

1.0

1.5

2.0

-0.01

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

Amplitude

Fre

qu

en

cy (

GH

z)

020

40

60

80

100

120

140

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

Normalized voltage [sqrt(W)]

Time (ns)

0.0

0.5

1.0

1.5

2.0

0.00

0.02

0.04

0.06

0.08

0.10

Amplitude

Frequency (GHz)

PIC

sim

ula

tion I

.

12

Bea

m p

aram

eter

s

-o

ffse

t (3

mm

,3m

m)

-3

.2 n

C

-2

4 m

m r

ms

len

gth

24

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

-0.010.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

Amplitude

Angle (rad)

01

23

4

0.00

0.02

0.04

0.06

0.08

0.10

Amplitude

Off

se

t (m

m)

PIC

sim

ula

tion I

I.

Eq

uiv

alen

t p

osi

tio

n s

ign

al o

f tr

ajec

tory

an

gle

is

~ 0

.43

µm

/ µ

rad

(0

.44

µm

/ µ

rad

)

25

Fer

mil

ab a

ctiv

itie

s /

Cold

cav

ity B

PM

for

NM

L

Des

ign p

aram

eter

s an

d c

alcu

late

d s

ignal

s.

Parameter

Unit

Value

Dip

ole

fre

quen

cyG

Hz

1.3

QL

640

Qex

t710

Bea

m p

ipe

radiu

sm

m39

Cav

ity

Rad

ius

mm

112

Cav

ity

Len

gth

mm

18

Signal

ILC-like

Project-X like (Single / Multi)

Ther

mal

nois

e (µ

V)

44

Dip

ole

at

1µ

m (

µV

)400

(5.5

/ 2

75)

Monop

ole

at

1.3

GH

z (µ

V)

74

(1.0

/ 0

.5)

Bea

m t

raje

ctory

angle

(µ

m/µ

rad)

0.4

40.4

4

26

Fer

mil

ab a

ctiv

itie

s /

Oth

er a

ctiv

ity

Cav

ity B

PM

for

CL

IC

Accuracy

Resolution

Stability

Range

Bandwidth

Beam tube

aperture

Available le

ngth

Intercepting

device?

How m

an

y?

Used in RT

Feedback?

Machine p

rotection It

em?

Comments

Ref

BPM

5µm

50nm

100nm

35MHz8.0mm

95/65mm

No

4176

Yes

Yes

Choke BPM?

Inductive BPM

CLIC note

764

BPM

20

µm

2µm

?<5mm

35MHz

23mm

104/74mm

No

41480

Yes

Yes

Inductive ?

Strip line?CLIC note 764

Drive beam

Accuracy

Resolution

Stability

Range

Bandwidth

Beam tube

aperture

Available len

gth

Intercepting

device?

How m

a

ny?

Used in RT

Feedback?

Machine pr

otection Ite

m?

Comments

Ref

Main beam

Info

rmal

yet

!

27

Futu

re w

ork

/ R

emote

mac

hin

e st

udy f

or

futu

re w

ork

.

PLS

Ferm

ilab

Rem

ote

acc

ess

from

Fer

mil

ab t

o P

LS

.

PL

S i

s 3

rdgen

erat

ion s

ynch

rotr

on r

adia

tion s

ourc

e.

Const

ruct

ion p

roje

ct:

Ap

ril

1988 ~

Dec

emb

er 1

994.

PL

S I

I p

roje

ct:

Januar

y 2

009 ~

Dec

emb

er 2

011.

Ener

gy

2.5

->

3.0

GeV

/ M

any

ID

s

28

Mac

hin

e m

onit

ori

ng. (2

009. 01. 31)

Futu

re w

ork

/ R

emote

mac

hin

e st

udy f

or

futu

re w

ork

.

29

Lat

tice

corr

ecti

on. (2

009. 02. 28)

05

010

01

50

200

250

300

-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

(βLOCO − βdesign) / βdesign

s (

m) B

efo

re L

OC

O a

pplic

ation

Aft

er

LO

CO

ap

plic

ation

05

010

01

50

200

250

300

-0.2

-0.1

0.0

0.1

0.2

0.3

Be

fore

LO

CO

ap

plic

ation

Aft

er

LO

CO

ap

plic

ation

s (

mm

)

(βLOCO − βdesign) / βdesign

05

10

15

20

25

30

35

40

-2-1012

desig

n v

alu

e

fitte

d v

alu

e

Q6 F

am

ily

Q5 F

am

ily

Q4 F

am

ily

Q3 F

am

ily

Q2 F

am

ily

k1(m-2)

Quadru

po

le

Q1 F

am

ily

Futu

re w

ork

/ R

emote

mac

hin

e st

udy f

or

futu

re w

ork

.

1.

The

per

form

ance

of

rem

ote

contr

ol

was

ver

y g

ood.

Rem

ote

contr

ol

had

bee

n d

one

as i

f w

e w

ere

in P

LS

contr

ol

room

.

2.

We

hope

this

rem

ote

mac

hin

e st

udy

to i

ncr

ease

the

inte

rest

for

coll

abora

tion

bet

wee

n F

erm

ilab

and s

om

e ac

cele

rato

r L

ab. in

Kore

a.

30

Su

mm

ary KN

U a

ctiv

itie

s

•K

NU

hav

e p

erfo

rmed

cav

ity B

PM

R&

Ds

for

ILC

.

•S

yst

em f

or

cavit

y B

PM

dev

elo

pm

ent

is e

stab

lish

ed i

n K

NU

.

•L

ow

-Q c

avit

y B

PM

and

S-b

and c

avit

y B

PM

wit

h i

nte

rnat

ion

al

coll

abora

tion

is

bei

ng

per

form

ed i

n K

NU

.

Fer

mil

ab a

ctiv

itie

s

•T

he

dev

elop

men

t of

cold

cav

ity B

PM

for

ILC

is

alm

ost

don

e.

•D

esig

n s

tudie

s fo

r co

ld c

avit

y B

PM

for

NM

L a

re f

inis

hed

.

•C

avit

y B

PM

wo

rk f

or

CL

IC w

as i

nfo

rmal

ly s

tart

ed.

Futu

re w

ork

•T

he

resu

lt o

f re

mo

te m

ach

ine

stud

y w

as s

how

n t

o i

ncr

ease

th

e in

tere

st

for

coll

abora

tio

n.