Discovery 2020 Yuta Michimura Department of Physics, University of - PowerPoint PPT Presentation

Ando Lab Midterm Seminar April 21, 2020 Discovery 2020 Yuta Michimura Department of Physics, University of Tokyo

Contents • Looking back on the year 2019 • Working from home • My plans and expectations for the year 2020 • Hot topics (continued and expanded from 2019) - Ultralight dark matter search with interferometers - Optical levitation of photonic crystal mirror - Lorentz invariance test in space - SILVIA: Space Interferometer Laboratory Voyaging towards Innovative 2 Applications (c)Philip FONG / AFP

Review: My Plans JFY2019 Only upto ~0.97 Mpc Mostly not done Done for some tables KAGRA+ paper not done Work in progress (Paper with Somiya-san published) SILVIA Cavity constructed New collaboration 3 started (PnC, LMA)

Review: My Expectations JFY2019 Successful implementation Paper by Enomoto-kun Not achieved Partially done DONE at below 100 Hz Achieved good sensitivity but not started DONE Cryostat constructed PASSED From this year? 4

Effort Report for 2019 5

Effort Report for 2019 • Compared with 2018: - KAGRA slightly decreased, KAGRA+ halved - Quantum and dark matter doubled - DECIGO greatly increased • Many visits (thank you for supports!) For 2018 45.0% 19.9% 4.6% 0.0% 4.7% 2.3% 15.6% 8.0% without Virgo * Number of days spent was counted for each topic based on my personal record. 6 If n topics on the same day, 1/n was allocated for each topic.

Effort Report for 2020 (so far) 7

Working from Home • At first could not concentrate on work • Now I’m used to it. No commuting is convenient. • But I started to feel like I’m left behind • Lucky that most of the work can be done remotely with my brain and PC (which is not ideal for experimentalists, though) Sleep Sleep Eat Eat News Work Eat Work Eat Shop 8 Commute Chat Eat

Email Traffic over the Month • I was expecting a decrease, but slightly increased? (may be just a coincidence) https://emailanalytics.com/ 7 都府県 Started to work from home 緊急事態宣言 Test emails to check granite 9

Summary and News from JFY2019 • Significant achievements by group members • New projects such as SILVIA, DANCE and optical levitation mirror started as anticipated • Progress in KAGRA much less than anticipated (found tragedic issues: birefringence and frosting) • Visited (too?) many places, gave a number of talks, including lectures at TianQin Research Center and Durham University, and met new people • Wrote many applications (4 positions, 3 grants, involved in other 6 applications including a big one on dark matter) • Wrote EPJD review paper on mg-scale optomechanics, Parity article on KAGRA • New people related to dark matter • Time to realize ideas rather than coming up with new ideas? 10

Productivity for the Past 10 Years • 2019 was the most productive year by numbers • But this is just from past activities of group members As of April 2020 PhD Thesis B4->M1 11

Number of People in Ando Group • First big decrease in our group • 2020 will be the touchstone of our ability to keep up 12

Grants for JFY2020 • Largest over the past years • Largest output is expected Lorentz violation - observation! Optical levitation - mirrors! Quantum - mirrors! Axion - demonstration! ※ 間接経費含む 13

Balance between Topics • Work-work balance would be very important in coming years • Large scale vs Table top • Ongoing vs Emerging • Management vs Implementation …… 14

My Plans JFY2020 • Remaining things for O4 - OMC, beam shutter - Optical table cover for TRX and TRY - upgraded MZM? In-vac RF PDs and RF/DC QPDs? • Finish KAGRA+ paper, write birefringence paper • More concrete planning of SILVIA and DECIGO • Write SILVIA and DECIGO paper • Absorption calculations for optical levitation mirror • Start DANCE Act-1 observation • Introduce polarization optics to TRX and TRY of KAGRA • Search for ultralight dark matter with KAGRA data 15

My Expectations JFY2020 • New data analysis on GW polarization • Better control of filter cavity and more clear squeezing angle rotation • Pave the way to optical levitation mirror (photonic crystal or curvature from coating stress) • Stability confirmation paper for optical levitation • Start Lorentz violation search with upgraded setup • Q measurement at cryogenic temperatures • Coil-coil actuator paper • New people in our group 16

Schedules in JFY2020 • June: 16 th Patras Workshop @ Trieste, Italy → postponed to June 2021 • July: 13 th LISA Symposium @ Glasgow, UK ?? • September: 日本物理学会 @ 筑波大学 , 熊本大学 ?? • September: 日本天文学会 @ 弘前大学 ?? • September: LVKC @ Cardiff, UK ?? • October: JGRG30 @ 早稲田大学 ?? • March: 日本物理学会 @ 東京大学駒場キャンパス ?? 17

Hot Topics • 2019 ver (see slides) - DANCE: D ark matter A xion ri N g C avity E xperiment - Optical levitation of photonic crystal mirror - Lorentz invariance test in space - C-DECIGO: km scale GW detector in space • 2020 ver - Ultralight dark matter search with interferometers - Optical levitation of photonic crystal mirror - Lorentz invariance test in space - SILVIA: Space Interferometer Laboratory Voyaging towards Innovative Applications 18

Laser Interferometry • Great tool to probe fundamental mysteries of our Universe • Laser interferometric gravitational wave detectors can be sensitive to various physics other than gravitational waves • Small scale experiments can beat large scale experiments Alternative Dark polarization energy modes Gravitational Cosmic expansion, Length change waves inflation δL /L Boson cloud Dark around BHs Laser B-L bosons matter Non-standard Speed of light Mirror forces change δc /c displacement Fringe change wave function ∝ δL /L, δc /c anisotropy polarization Axion extra collapse dependence dimensions Lorentz violation Quantization quantization of 19 of gravity spacetime

Dark Matter • We know they exist everywhere and we know they played an important role in forming our Universe, but we don’t know what they are at all 21

Past Searches: WIMPs • Wide range of candidates, but many focused on WIMPs • WIMP searches will be soon limited by neutrino background Park (2007) https://cerncourier.com/a/defeating-the-background- in-the-search-for-dark-matter/ PBHs 22 (upto 100 Msun = 1e59 GeV)

A New Era G. Bertone, T. M. P. Tait, Nature 562, 51 (2018) 23

Laser Interferometric Search • Strong tool to search for ultralight dark matter (wave-like dark matter) • Dark matter Axion search with riNg Cavity Experiment (DANCE) I. Obata, T. Fujita, YM, PRL 121 , 161301 (2018) • DM Axion search with laser interferometric GWD K. Nagano, T. Fujita, YM, I. Obata, PRL 123 , 111301 (2019) • B-L gauge boson search P. W. Graham+, PRD 93 , 075029 (2016) A. Pierce+, PRL 121 , 061102 (2018) D. Carney+, arXiv:1908.04797 • Search through fine-structure constant change H. Grote & Y. V. Stadnik, PRR 1 , 033187 (2019) • New searches with strong magnets R. Creswick, F. T. Avignone III, arXiv:2004.01642 24

DANCE • Axion-photon coupling ( ) gives different phase velocity between left-handed and right- handed circular polarizations axion mass coupling constant axion field • Measure the difference as resonant frequency difference in an bow-tie cavity 25

DANCE Act-1 • L= 1 m, Finesse = 3e3, Pin= 1 W • Also good for practicing a cavity experiments ∝ m a 1/2 ∝ m a 5/4 scan ∝ m a 5/4 T coh >T obs cavity pole ∝ m a 0 ∝ m a 1/4 ∝ m a 1/2 scan ∝ m a 1 26

DANCE Act-2 • L= 1 m, Finesse= 2e5, Pin= 1 W, Tobs= 3 months • New idea to do coherent search with two cavities • Table-top experiment is complementary to large-scale experiments like GW detectors Axion-photon coupling CAST γ -ray from SN1987A X-ray from M87 DANCE Act-2 Advanced LIGO (two cavities) (4 km) KAGRA (3 km) 27

DM Axion Search with GWDs • Different method is required for linear cavities in GW detectors Modulation at frequency • Axion-photon coupling create modulation in polarization p-pol angle of linear polarization • Sensitive when modulation period and round-trip time of light in a cavity are the same • Can be searched left-handed along with GWs p-pol is faster FI Laser right-handed is faster p-pol s-pol (GW signal) (Axion signal) 28

B-L Gauge Boson • Difference between baryon number and lepton number • B-L is conserved very well and could be a charge of U(1) B-L symmetry → It is natural to think that some gauge boson is coupled Baryon Lepton • Related to baryon asymmetry through leptogenesis 浜口幸一 (2017) 29

Gauge Boson Search • Several groups proposed laser interferometric search with GW detectors and mg-scale optomechanical experiments P. W. Graham+, PRD 93 , 075029 (2016) A. Pierce+, PRL 121 , 061102 (2018) D. Carney+, arXiv:1908.04797 • When mirrors have different B-L ratio (~neutron ratio), different resonant frequency, or mirrors are apart, amplitude or phase of force acting on mirrors are different and DM signal remains 30