A b o u t g r a v i t a t i o n a l w a v e d - PowerPoint PPT Presentation

A b o u t g r a v i t a t i o n a l w a v e d e t e c t o r s A b o u t g r a v i t a t i o n a l w a v e d e t e c t o r s L o ï c R o l l a n d L a b o r a t o i r e d ’ A n n e c y d e P h y s i q u e d e s P a r t i c u l e s DAUTREPPE 2018 Dernières nouvelles de l’univers Université Grenoble-Alpes Saint Martin d’Hères December 5 th 2018

T T h h e e g g r r a a v v i i t t a a t t i i o o n n a a l l w w a a v v e e ( ( G G W) W) s s p p e e c c t t r r u u m m C o s m i c s t r i n g s B i n a r i e s o f b l a c k S u p e r n o v a e B i n a r y m e r g e r s h o l e s a n d n e u t r o n s t a r s R e l i c r a d i a t i o n S u p e r m a s s i v e b i n a r y E x t r e m e m a s s r a t i o b l a c k h o l e b i n a r i e s b i n a r i e s R o t a t i n g n e u t r o n s t a r s 2 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

G r o u n d - b a s e d i n t e r f e r o m e t e r s G r o u n d - b a s e d i n t e r f e r o m e t e r s ( ( G G W W i i n n t t h h e e r r a a n n g g e e 1 1 0 0 H H z z t t o o f f e e w w k k H H z z ) ) 3 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

D e t e c t i n g g r a v i t a t i o n a l w a v e s D e t e c t i n g g r a v i t a t i o n a l w a v e s w w i i t t h h g g r r o o u u n n d d - - b b a a s s e e d d i i n n t t e e r r f f e e r r o o m m e e t t e e r r s s M a s s e s i n m o t i o n S p a c e - t i m e d e f o r m a t i o n G r a v i t a t i o n a l w a v e h(t) : a m p l i t u d e o f t h e G W 3 km h ( h a s n o d i m e n s i o n ) time F o r G W1 7 0 8 1 4 , fj r s t V i r g o d e t e c t e d e v e n t : - 2 2 - 1 8 h = 5 x 1 0 → δ L = ± 0 . 8 x 1 0 m 4 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

A n i n t e r n a t i o n a l n e t w o r k o f d e t e c t o r s A n i n t e r n a t i o n a l n e t w o r k o f d e t e c t o r s N e t w o r k w o r k i n g a s a s i n g l e d e t e c t o r s i n c e 2 0 0 7 T h e n e t w o r k i s a “ G r a v i t a t i o n a l w a v e t e l e s c o p e ” ✔ R e j e c t i o n o f s p u r i o u s l o c a l n o i s e ( c o i n c i d e n c e ) → b e t t e r s e n s i t i v i t y ✔ S o u r c e l o c a l i s a t i o n ( t r i a n g u l a t i o n ) → a s t r o n o m y ✔ Wa v e p o l a r i z a t i o n 5 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

O O p p t t i i c c a a l l c c o o n n fj fj g g u u r r a a t t i i o o n n , , d d e e t t e e c c t t o o r r c c o o n n t t r r o o l l s s a a n n d d h h i i n n t t s s o o f f d d e e t t e e c c t t o o r r s s s s e e n n s s i i t t i i v v i i t t y y 6 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

S S i i m m p p l l e e M M i i c c h h e e l l s s o o n n i i n n t t e e r r f f e e r r o o m m e e t t e e r r C o m p u t a t i o n o f p o w e r o u t p u t a s s u m i n g p l a n e w a v e s : E q u i v a l e n t s i z e o f V i r g o b e a m We d o n o t m e a s u r e n i c e f r i n g e i m a g e s ! 7 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

L L o o n n g g i i t t u u d d i i n n a a l l l l y y - - c c o o n n t t r r o o l l l l e e d d M M i i c c h h e e l l s s o o n n i i n n t t e e r r f f e e r r o o m m e e t t e e r r S e t t i n g a w o r k i n g p o i n t With C=1 C o n t r o l l e d m i r r o r p o s i t i o n s F r e e l y s w i n g i n g m i r r o r s P o w e r v a r i a t i o n s a s a f u n c t i o n o f s m a l l d i fg e r e n t i a l l e n g t h v a r i a t i o n s 8 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

I I m m p p r r o o v v i i n n g g t t h h e e s s e e n n s s i i t t i i v v i i t t y y w w i i t t h h r r e e s s o o n n a a n n t t c c a a v v i i t t i i e e s s I n c r e a s e t h e i n p u t p o w e r I n c r e a s e t h e p h a s e d i fg e r e n c e o n B S b e t w e e n t h e a r m s f o r a g i v e n d i fg e r e n t i a l a r m l e n g t h v a r i a t i o n R e c y c l i n g c a v i t y F a b r y - P e r o t c a v i t i e s i n t h e a r m s 9 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

A A h h i i n n t t o o f f ( ( s s h h o o t t - - n n o o i i s s e e l l i i m m i i t t e e d d ) ) s s e e n n s s i i t t i i v v i i t t y y Response of recycled Michelson with Fabry- Perot cavities: 3-km Fabry-Perot cavities Input beam BS Power recycling cavity Sensor 10 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

A A d d v v a a n n c c e e d d V V i i r r g g o o o o p p t t i i c c a a l l l l a a y y o o u u t t F a b r y - P e r o t c a v i t i e s ( 3 k m , fj n e s s e 4 5 0 ) I n p u t - M o d e - C l e a n e r c a v i t y ( ~ 1 0 0 m ) P o w e r R e c y c l i n g a n d S i g n a l R e c y c l i n g O u t p u t - M o d e - C l e a n e r c a v i t i e s C a v i t i e s ( ~ 7 c m ) 11 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

D D e e t t e e c c t t o o r r n n o o m m i i n n a a l l s s e e n n s s i i t t i i v v i i t t y y New mirror suspensions Wider laser beam Improved vacuum More powerful laser and Signal recycling 12 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

C C o o n n t t r r o o l l l l i i n n g g t t h h e e w w o o r r k k i i n n g g p p o o i i n n t t o o f f t t h h e e i i n n t t e e r r f f e e r r o o m m e e t t e e r r Photodiode C a v i t i e s t u n e d s o t h a t t h e d i fg e r e n t b e a m s a r e n o t a l l r e s o n a n t i n a l l → i m p r i n t o f c a v i t y l e n g t h s i n t h e i n t e r f e r e n c e b e t w e e n b e a m s , h e n c e i n d e t e c t e d p o w e r → ( d i g i t a l ) d e m o d u l a t i o n a t Ω t o e x t r a c t Phase c a v i t y l e n g t h e r r o r s i g n a l modulator Input Photodiode beam M a i n b e a m “ S i d e b a n d s ” b e a m s = 1 0 6 4 n m a t f = f 0 ± Ω λ F o r c e a p p l i e d o n t h e m i r r o r s v i a 0 f o r c o n t r o l s f ~ 3 x 1 0 1 4 H z e l e c t r o m a g n e t i c a c t u a t o r s t o k e e p t h e 0 ( Ω f e w M H z ) c a v i t i e s l o c k e d a t t h e i r n o m i n a l l e n g t h Photodiode 13 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble

A A c c a a v v i i t t y y t t o o c c l l e e a a n n t t h h e e i i n n t t e e r r f f e e r r o o m m e e t t e e r r o o u u t t p p u u t t b b e e a a m m C o n t r o l o f t h e c a v i t y l e n g t h t o Beam wavelength k e e p r e s o n a n c e o f t h e Main beam selection G a u s s i a n m o d e o f m a i n b e a m Sidebands - P e l t i e r c e l l - P i e z o a c t u a t o r 2 bow-tie cavities in series Beam geometry selection Gaussian beam, Higher order modes the one sensitive to in the output beam gravitational waves (due to interferometer imperfections) 14 L. Rolland - 5th December 2018 - Séminaire Dautreppe, Grenoble