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Silicon and Suprasil results with GeNS
Investigation on annealing effect in a Suprasil sample and loss measurements in silicon samples Elisabetta Cesarini a,b), Gianpietro Cagnoli a,c), Enrico Campagna a,d), Matteo Lorenzini a,b), Giovanni Losurdo a), Filippo Martelli a,d), Francesco Piergiovanni a,d) , Flavio Vetrano a,d) a) b) c) d) INFN Sez. Firenze Università di Firenze (Dip. Astronomia e Scienza dello Spazio) University of Glasgow Università di Urbino 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 1 Summary Last ILIAS-GW meeting 26-27 October 2006 we presented: Q measurement facility Innovative nodal suspension, designed and realized (GeNS) Now: We are measuring the loss angle of different interesting materials: •Herasil •Suprasil (annealed sample, that we are investigating with surface analysis) •Silicon (we are trying to calculate the thermoelastic contribution to fit our measurements) 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 2 Dissipation measurements on Suprasil samples Q-value @3469 Hz (lower frequency) Q-value @7889 Hz (higher frequency) SAMPLE: Suprasil 311 disk 75x3 mm (75x3 mm Suprasil disk and D_sphere= 4.75 mm) (75x3 mm Suprasil disk and D_sphere= 4.75 mm) Contact surface (radius 20 mm) Q-value +/- 5%) @3469 @7890 Hz Hz (lower (higher frequency) Q-value(in(inmilions milions+/-5%) frequency) (75x3 Suprasil disk disk and andD_sphere= D_sphere=4.75 4.75mm (75x3 m m Suprasil mm ) ) Q value Q value Sapphire sphere D= 4.75 mm 1,72E+07 1,17E+071,75E+07 1,75E+07 1,17E+07 1,71E+07 1,17E+071,79E+07 1,22E+07 2,00E+07 1,40E+07 1,74E+07 1,17E+07 1,81E+07 1,24E+07 1,72E+07 1,20E+07 1,11E+07 1,50E+07 1,20E+07 1,75E+07 1,00E+07 1,19E+07 8,00E+06 1,00E+07 6,00E+06 4,00E+06 5,00E+06 30 30 1313 2,00E+06 0,00E+00 0,00E+00 12,2 17,1 17,2 y displacement [ m y displacement [ m] m m] y y -13 -13 20 20 11,7 00 00 x x [mm[mm] ] 17,5 11,7 [m m] -13 -13 [mm] 13 10 10 18,1 12,4 17,5 11,7 -30 -30 -20 -20 00 -10 -10 00 -10 -10 17,4 11,1 -20 -20 10 10 20 20 17,911,7 30 30 7890 3469 Hz 2° 1° Butterfly mode 12,0 17,2 11,9 17,5 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 -30 -30 displacem ent xx displacem ent [mm [mm]] 3 Dissipation measurements on Suprasil samples Measurement after the annealing: Q(3469Hz)=2·107 First measurement: Q(3469Hz)=2.7·106 it is smaller by a factor two!! Anneal in FI samples air (suggested by S.Penn): -Raise the oven temperature to the annealing point (1120°C for Similar samples Suprasil) - Cool down to the strain temperature (1025°C for Suprasil) with a rate of about 10 degrees per hour V/S = 1.3875 μm Taken from Mechanical Loss in Fused Silica -8 Steveand Penn wait for -Turn off the oven φPenn = 2 · 10 Hobart and William Smith Colleges cool downLSC in 24 hours QPenn = 50 millions Meeting, March 2006 LIGO DCC LIGO-G0601 40-00-Z millions 4° ILIAS-GWA AnnualQ Meeting Tubingen (D), October 8-9, 2007 4 exp = -20 Annealing study Is the Q value increasing due to an internal or a surface effect? Surface Analysis In collaboration with: INFN sezione Genova and Università di Genova counts/s Ellipsometry and XPS Binding Energy (eV) 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 5 Dissipation measurements on silicon samples Samples: RESULT SUMMARY •75x1 mm •75x3 mm sapphire sphere (d=4.76 mm) •75x10 mm sapphire sphere (d=15-20 mm) Bad reproducibility of measurements in different suspensions CLEANING PROCEDURE We have to work in a clean room!!! 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 6 Dissipation measurements on silicon samples Q value vsthe frequency Taking into account only maximum values … (75x10 mm silicon disk, sapphire sphere Rc=15 mm) 1,80E+07 Q value14730 vs frequency Hz 1st butterfly mode 1,60E+07 4,00E+06 50906 Hz 3rd butterfly mode 3,50E+06 1,20E+07 3,00E+06 1,00E+07 Max Q-value Max Q-value 1,40E+07 (75x3 mm silicon disk, sapphire sphere Rc=4.76 mm) 31551 Hz 2nd butterfly mode 8,00E+06 6,00E+06 4,00E+06 2,50E+06 2,00E+06 1,50E+06 1,00E+06 2,00E+06 5155 Hz 1st butterfly mode 11781 Hz 2nd butterfly mode 0,00E+00 0 5,00E+05 20353 Hz 3r butterfly mode 10000 20000 30000 40000 50000 60000 0,00E+00 frequency [Hz] 0 5000 10000 15000 20000 25000 frequency [Hz] 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 7 Thermoelastic contribution calculation Thermoelastic contribution for a disk of finite dimensions Previous calculations : How to solve the problem - F. Bondu, P. Hello, J.Y. Vinet, of Phys. Lett A 246 (1998) 227 Liu andin K.S. Thorne, Phys. Rev. D 62 (2000) 122002 the-Y.T. sources a non-adiabatic - V. B. for Braginsky, M.L. Gorodetski, S.P. Vyatchanin, Phys Lett. A 264 (1999) 1 condition a cristalline material? ADIABATIC APPROXIMATION: We wantbytoheat simulate The DT is not influenced fluxesthe vibrations of the disk with ANSYS, then take the time derivative of the deformations and put them in the diffusion heat equation. What is our idea? We want to calculate exactly the thermoelastic contribution without any approximation 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 8 Next work… 1. New surface analysis after the annealing, trying to understand if the produced effect is internal or superficial. 2. Calculation of the thermoelastic contribution in silicon disks, without any approximation. 3. New loss measurements of the silicon samples with different thickness (in collaboration with Jena University). 4. Measurements of mechanical properties of coated samples suitably altered or damaged. 4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007 9 Thanks for your attention 10