As Assembly of of Pr Prot otot otyp ype Sapphi Sa hire e Su - PowerPoint PPT Presentation

As Assembly of of Pr Prot otot otyp ype Sapphi Sa hire e Su Suspens ension on Bin-Hua Hsieh 1 R Kumar 2 , T Suzuki 2 , T Yamada 1 , K Craig 1 , H Vocca 4 , K Yamamoto 3 , T Kajita 1 , T Tomaru 2 ICRR, The University of Tokyo 1 High Energy Accelerator Research Organization (KEK) 2 The University of Toyama 3 The University of Perugia, Italy 4 The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 1

Ou Outlin tline l Design of Sapphire Suspension System l Assembly of Sapphire Suspension l Sapphire Fiber Strength Test l Future Work l Summary The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 2

Cr Cryogenic Pa Payload System Operational temperature - 20 K Sapphire Suspension The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 3

Wh Why y do o we e use e Sap apphire? e? 2×10 , l To reduce the thermal noise fluctuations and increase the sensitivity of the detector l Thermal noise power spectrum 𝑦 " ∝ 𝑈×𝜚 = 𝑈 𝑅 T. Uchiyama et al., Physics Letters A 261(1999)5 The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 4

Th Thermal al Noi oise se K. Yamamoto et al., PHYSICAL REVIEW D 74, 022002 (2006) The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 5

Sap Sapphir ire Su Suspension ion Indium Each fiber should support a load of 5.75 kg Credit: R Kumar, ANSYS model Indium The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 6

As Assembly ly of f Prototyp ype Sa Sapphir ire Sus Suspens pensio ion 1. Assembled of all metal prototype(22 kg dummy mirror, CuBe blade springs and metal fibers) 2. Replaced metal dummy mirror with sapphire mirror 3. Replaced CuBe blade spring with sapphire blade spring 4. Replaced metal fibers with sapphire fibers and suspend the sapphire mirror Ch Characterization on (S (Sapphire S Suspension on) 1. Check the strength of the suspended system 2. Measure the resonant frequency of sapphire suspension system 3. Perform a cool down test in cryostat at KEK The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 7

Earthquake stopper 22kg dummy mirror All metal prototype Fiber holder Replace with sapphire mirror The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 8

Nail head clamps 3 axis linear stages Brackets for attachment at support structure Sapphire fiber holders The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 8

Intermediate mass Micrometer screw Copper clamp Sapphire blade springs Sapphire fiber The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 9

Fi Fiber ber S Streng ength T h Tes est • Proof check – Sapphire fibers should survive 6 kg & 12 kg load test for 1 hour each (safety factor 2) • We strength tested 22 sapphire fibers from IMPEX • 12 sapphire were found to be strong • 10 fibers were found to be weak at weld points Load 6 kg Load 12 kg The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 11

Wh Why y Sapphire Fiber broke? 2014 fibers construction schematic 2015-16 fibers construction schematic Only 1 of the 6 fibers in 2014 batch Finally 12 sapphire fibers out of 16 survived 6kg load (i.e. 5 were survived 12 kg load test (1 hour of broken) hanging) The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 12

Su Succe ccessfu ful test hang g of f Sa Sapphire Su Suspension On May 13 th 2017, we suspended 22kg sapphire test mass on 4 sapphire fibers and 4 sapphire blade springs The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 13

Fu Futu ture Work rk 1. Measure the resonant frequency of sapphire suspension system 2. Perform a cool down test in cryostat The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 14

Su Summary l We performed test hanging using metal blade springs and fibers, then replaced metal components with sapphire in a step by step process. l We tested the sapphire fibers strength using 6kg and 12 kg mass. 12 fibers survived the strength test. l We successfully assembled and suspended the prototype sapphire suspension system. The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 15

The End Thanks for your listening! The 3 rd KAGRA International Workshop @Academia Sinica, Taipei May 21 st , 2017 16