C a l i b r a t i o n o f a g r a v i t a t i - - PowerPoint PPT Presentation

SLIDE 1

C a l i b r a t i

• n
• f

a g r a v i t a t i

• n

a l w a v e d e t e c t

• r

D . E s t e v e z P h D S t u d e n t

• L

A P P

D a u t r e p p e

• 5

/ 1 2 / 2 1 8

SLIDE 2

Dautreppe - 05/12/2018 2

P

• n

c t u a l t e s t ma s s e s G r a v i t a t i

• n

a l w a v e s

E f f e c t

• f

g r a v i t a t i

• n

a l w a v e s

P e r t u r b a t i

• n

s

• f

t h e me t r i c : h ( t ) S t r e t c h a n d s q u e e z e s p a c e t i me b e t w e e n p a r t i c l e s w i t h r e s p e c t t

• t

h e w a v e p

• l

a r i z a t i

• n

SLIDE 3

Dautreppe - 05/12/2018 3

Beam-splitter Mirror Interference pattern Photodetector

Credit: H. Lück AEI Hannover

Laser

Mi c h e l s

• n

i n t e r f e r

• me

t e r

SLIDE 4

Dautreppe - 05/12/2018 4

Controls Controls photodetectors

A d v a n c e d V i r g

• West

North Signals T h e c

• n

t r

• l

s c a n c e l t h e d i s p l a c e me n t

• f

t h e mi r r

• r

s d u e t

• d

i f f e r e n t n

• i

s e s b u t a l s

• t

h e g r a v i t a t i

• n

a l w a v e s i g n a l h ( t ) . . .

SLIDE 5

Dautreppe - 05/12/2018 5

R e c

• n

s t r u c t i

• n
• f

h ( t )

h ( t )

(Sf x OITF)-1

P h

• t
• d

i

• d

e s i g n a l s ( W)

Gi Ai

mir/mar

C

• r

r e c t i

• n

s i g n a l s ( V )

GITF

• 1

L0

• 1

R e c

• n

s t r u c t i

• n
• f

h ( t )

➔ S

u b t r a c t c

• n

t r

• l

s i g n a l s f r

• m

d a r k f r i n g e s i g n a l

➔ C

• r

r e c t f

• r

t h e i n t e r f e r

• me

t e r

• p

t i c a l r e s p

• n

s e N e e d t

• b

e c a l i b r a t e d !

SLIDE 6

Dautreppe - 05/12/2018 6

Wh a t i s c a l i b r a t i

• n

?

• N

e e d t

• u

n d e r s t a n d t h e d e t e c t

• r

r e s p

• n

s e w h e n a n e x t e r n a l s i g n a l c h a n g e s t h e d i f f e r e n t i a l a r m l e n g t h a n d e x t r a c t t h e e x t e r n a l p e r t u r b a t i

• n
• Me

a s u r e t h e d e t e c t

• r

s e n s i t i v i t y h ( f )

• R

e c

• n

s t r u c t i n r e a l t i me t h e e v

• l

u t i

• n
• f

t h e a mp l i t u d e s i g n a l h ( t )

• S

i mu l a t e g r a v i t a t i

• n

a l w a v e s i g n a l s b y mo v i n g t h e mi r r

• r

s

Δ L=LN−LW hext= Δ L L0 , L0=3km

A d v a n c e d V i r g

• c

u r r e n t s e n s i t i v i t y

h ( f )

SLIDE 7

Dautreppe - 05/12/2018 7

E l e c t r

• ma

g n e t i c a c t u a t

• r

s

T e s t ma s s C

• i

l s Ma g n e t s

L A S E R

Mu l t i p l e s u s p e n s i

• n

s t a g e s

• A

p p l y a v

• l

t a g e

• n

t h e c

• i

l s ( V )

• >

Mo v e s t h e mi r r

• r

s ( m)

• R

e f e r e n c e i s t h e w a v e l e n g t h

• f

t h e I T F : 1 6 4 n m

• Me

a s u r e t h e

• p

t i c a l s i g n a l w h e n t h e i n p u t mi r r

• r

s mo v e f r e e l y a n d r e c

• n

s t r u c t

• I

n p u t mi r r

• r

s a n d b e a ms p l i t t e r a r e t h e n c a l i b r a t e d

• T

r a n s f e r p r

• c

e d u r e s t

• c

a l i b r a t e t h e

• t

h e r mi r r

• r

s w h e n c

• n

t r

• l

l e d

Δ Lfree

D u r i n g t h e

• b

s e r v a t i

• n

r u n O 2 ( A u g u s t 2 1 7 f

• r

V i r g

• )

S y s t e ma t i c u n c e r t a i n t i e s w e r e :

➢ 1

, 1 % i n a mp l i t u d e ( m/ V )

➢ 5

mr a d

• n

p h a s e

SLIDE 8

Dautreppe - 05/12/2018 8

U n c e r t a i n t y

• n

h ( t )

Mo v i n g a mi r r

• r

➢ h

i n j }

R e c

• n

s t r u c t i

• n
• f

t h i s d i s p l a c e me n t u s i n g t h e w h

• l

e i n t e r f e r

• me

t e r

➢ h

r e c

±4 % a mp l i t u d e ±3 5 mr a d p h a s e σhrec = ±5 . 1 % a mp l i t u d e σhrec = ±(4 mr a d + 2 πf τ) o ù τ = 2 µs

l a s e r p h

• t
• d

i

• d

e

➢ C

• mp

u t e hrec/hinj

C l a s s . Q u a n t . G r a v . 3 5 ( 2 1 8 ) n

• .

2 , 2 5 4

SLIDE 9

Dautreppe - 05/12/2018 9

U n c e r t a i n t y

• n

h ( t )

Mo v i n g a mi r r

• r

➢ h

i n j }

R e c

• n

s t r u c t i

• n
• f

t h i s d i s p l a c e me n t u s i n g t h e w h

• l

e i n t e r f e r

• me

t e r

➢ h

r e c

±4 % a mp l i t u d e ±3 5 mr a d p h a s e σhrec = ±5 . 1 % a mp l i t u d e σhrec = ±(4 mr a d + 2 πf τ) o ù τ = 2 µs

l a s e r p h

• t
• d

i

• d

e

➢ C

• mp

u t e hrec/hinj

C l a s s . Q u a n t . G r a v . 3 5 ( 2 1 8 ) n

• .

2 , 2 5 4

I N D E P E N D E N T M E T H O D S N E E D E D

SLIDE 10

Dautreppe - 05/12/2018 10 ( P

r e f

) F a i s c e a u l a s e r p r i n c i p a l C â b l e s ⃗

F

P h

• t
• n

c a l i b r a t

• r

( P c a l )

S u s p e n s i

• n

s S u s p e n d e d mi r r

• r

( ma s s m) R e f l e c t e d l a s e r b e a m ( P

r e f

) I n t e r f e r

• me

t e r l a s e r b e a m A u x i l i a r y l a s e r b e a m

Mo v i n g t h e mi r r

• r

s b y r a d i a t i

• n

p r e s s u r e :

x (t)=− 1 m F (t) (2 π f )

2

F (t)= 2 cos (i) c Pref (t)

SLIDE 11

Dautreppe - 05/12/2018 11

WE

Injection Reflection

P c a l s e t

• u

p

• n

A d v a n c e d V i r g

SLIDE 12

Dautreppe - 05/12/2018 12

C h e c k i n g h ( t ) w i t h t h e P c a l

➢ C

• n

s i s t e n t w i t h t h e u n c e r t a i n t i e s g i v e n f

• r

h ( t ) r e c

• n

s t r u c t i

• n

d u r i n g t h e

• b

s e r v a t i

• n

r u n O 2 w i t h t h e e l e c t r

• ma

g n e t i c a c t u a t

• r

s A mp l i t u d e : ± 4 % P h a s e : ± ( 3 5 mr a d + 2 πf τ) w i t h τ = 7 µs

C l a s s . Q u a n t . G r a v . 3 5 ( 2 1 8 ) n

• .

2 , 2 5 4

SLIDE 13

Dautreppe - 05/12/2018 13 Mirror

x axis

N e w t

• n

i a n c a l i b r a t

• r

( N c a l )

➢ R

• t
• r

ma d e

• f

t w

• ma

s s e s

➢ N

• n
• l

i n e a r N e w t

• n

i a n f

• r

c e g e n e r a t e s t h e s i g n a l

➢ S

i g n a l a t t w i c e t h e f r e q u e n c y

• f

t h e r

• t
• r

➢ 1

/ d

4

e f f e c t

NCal moving line

Hz

➢ S

t i l l i n d e v e l

• p

me n t

➢ P

r

• mi

s i n g r e s u l t s f

• r

f u t u r e c a l i b r a t i

• n

SLIDE 14

Dautreppe - 05/12/2018 14

N c a l s e t

• u

p

• n

A d v a n c e d V i r g

• N

c a l s Vacuum tube End tower

SLIDE 15

Dautreppe - 05/12/2018 15

C h e c k i n g h ( t ) w i t h t h e N c a l

→ Me a s u r e d / e x p e c t e d N C a l l i n e s a mp l i t u d e a r e c

• n

s i s t e n t w i t h t h e c

• i

l s i n j e c t i

• n

s me a s u r e me n t s . → B e t t e r c

• n

t r

• l
• f

t h e s y s t e ma t i c u n c e r t a i n t i e s ( ma s s , d i s t a n c e . . . ) → A b s

• l

u t e c a l i b r a t i

• n

b e l

• w

1 % s e e ms p

• s

s i b l e .

C l a s s . Q u a n t . G r a v . 3 5 ( 2 1 8 ) n

• .

2 3 , 2 3 5 9 h r e c / h i n j

SLIDE 16

Dautreppe - 05/12/2018 16

E M P c a l N c a l

F Mirror x axis A u x i l i a r y l a s e r b e a m I n t e r f e r

• me

t e r l a s e r b e a m R e f l e c t e d l a s e r b e a m ( P

r e f

) T e s t ma s s C

• i

l s Ma g n e t s

S u mma r y

• f

c a l i b r a t i

• n
• C

a l i b r a t i

• n
• f

MI R / MA R a c t u a t

• r

s

• C

h e c k h r e c u p t

• 1

k H z b u t w i t h t h e s a me mo d e l

• C

a l i b r a t i

• n
• f

MI R / MA R a c t u a t

• r

s

• I

n d e p e n d e n t c h e c k h r e c f r

• m

a f e w H z t

• a

f e w k H z

• S

y s t e ma t i c u n c e r t a i n t i e s n

• t

e a s y t

• c
• n

t r

• l

( p

• w

e r . . . )

• C

a l i b r a t i

• n
• f

MI R / MA R a c t u a t

• r

s

• I

n d e p e n d e n t c h e c k h r e c u p t

• a

f e w h u n d r e d s

• f

H z

• B

e t t e r c

• n

t r

• l
• f

s y s t e ma t i c u n c e r t a i n t i e s ( ma s s , d i s t a n c e . . . )

SLIDE 17

17

T h a n k y

• u

!

A n y q u e s t i

• n

s ?