Gravitational Radiation Detectors

Rana X Adhikari ICTS / RRCAT Caltech GW School / Dec 2013

1 They Exist !

On the Earth: TAMA 300 / KAGRA - Tokyo / Toyama, Japan GEO 600 / HF - Hannover/Ruthe, Germany Virgo 3000 / AdVirgo - Pisa/Cascina, Italy LIGO 4000 / aLIGO - Washington+Louisiana, USA

BARS: ALLEGRO, AURIGA, NAUTILUS, EXPLORER

Space:

LISA 5x10^6 - Orbiting the Sun (2035-2040) Pulsar Timing (IPTA) - Analyzing Radio data (NOW) BBO/DECIGO - Directly Observe Inflation (???)

2 GWs and Bars First ground-based detectors— the beginning of GW detection: Weber Much improvement in Bars Cryogenics Quantum Limited Readout

Joe Weber + Bar

Bar display at LIGO Hanford 3 Ju, L., D. G. Blair, and C. Zhao, 2000, Reports on Progress in Physics 63(9), 1317 First World-wide GW Network: IGEC International Gravitational Event Collaboration Established 1997 in Perth

Included all operating bar detectors in the world

Figure courtesy of Massimo Cerdonio

4 BS

Anti- Symmetric Port courtesy Lillian MacArthur PhotoDetector Bunnahabhain Distillery Michelson Cheat Sheet Phase Shift ∝ Arm Length d L d(strain) /

Ly dP Signal ∝ Laser Power 2⇡ PBS sin()cos() = (L L ) d / ⇥ y x

Lx Laser

Anti-Symmetric 2 (Dark) Port P PBS sin () ' ⇥

Shot Noise 1 P pP SNR Poisson/ Statistics... / pP optimum Typical 20th century Optical Configuration Michelson Interferometer + Fabry-Perot Arms end test mass + Power Recycling

km scale Fabry-Perot arm cavity

recycling mirror input test mass

Laser

beam splitter GW Signal Readout

7 http://www.srl.caltech.edu/lisa/graphics/LISA_science.html!

eLISA

8 http://www.srl.caltech.edu/lisa/graphics/LISA_science.html! Beyond Einstein Roadmap! 1979: Gravitational Waves Observed PSR1913+16: ‘Hulse-Taylor Binary Pulsar’

Arecibo Dish

9 http://nobelprize.org/nobel_prizes/physics/laureates/1993/ Timeline of GW Detectors

1970 1980 1990 2000 2010 2020 20NN ? ? ? ?

1st Tabletop 1st Bar Interferometer −13 Detectors (Forward, Malibu) 10

(Weber) −15 10

Interferometer −17 10 Hz]

Concept √ −19 (Weiss, MIT) 10

−21 10 Strain [1/

−23 10 Bars

−25 10 1970 1980 1990 2000 2010 2020 2030 2040 Time [year] LIGO: Laser Interferometer Gravitational-wave Observatory Hanford Nuclear Reservation, Eastern Washington - Two nearly identical sites (very different seismic, cultural environments) - Arms aligned to observe same polarization - Hanford used to have a 3rd interferometer of half length

Livingston, LA (L1 4km) ~1 hour from New Orleans Progress of LIGO Sensitivity

12 Anatomy of the Noise

13 GEO600

Interferometer with 600 m arms, located near Hannover, Germany

Developed many advanced techniques: monolithic glass suspensions, signal recycling, electro-static drive, stray charge reduction,...

14 GEO600 Sensitivity

15 GEO600:

Signal Recycling Mirror

Location of Signal Recycling Mirror Harald Lück Changes Frequency Response Rencontres de Moriond (Frequency of Maximum Sensitivity)

16 Virgo One interferometer with 3 km arms, located near Pisa, Italy

17 Virgo Office Building Progress of Virgo Sensitivity

19 TAMA300

300 m interferometer, located at National Astronomical Observatory of Japan (Tokyo)

Project started 1995

First large interferometer to begin observations

Best sensitivity in L=300m world 2000-2002

from Kazuaki Kuroda for the TAMA/CLIO/LCGT Collaboration Mitaka campus, National Astronomical Observatory

20 TAMA300 Sensitivity

21 A Global Network

GEO Virgo LIGO TAMA/KAGRA

• Detection confidence • Locate sources • Decompose the polarization of gravitational waves

t δ

L = c Δ θ LIGO-INDIA AIGO 1 2

22 Looking to the Future

23 LIGO Scientific Collaboration

lUniversity of Michigan lUniversity of Minnesota lAustralian Consortium lThe University of Mississippi for Interferometric lMassachusetts Inst. of Technology Gravitational Astronomy lMonash University lThe Univ. of Adelaide lMontana State University lAndrews University lMoscow State University lThe Australian National Univ. lNational Astronomical lThe University of Birmingham Observatory of Japan lCalifornia Inst. of Technology lNorthwestern University lCardiff University lUniversity of Oregon lCarleton College lPennsylvania State University lCharles Stuart Univ. lRochester Inst. of Technology lColumbia University lRutherford Appleton Lab lEmbry Riddle Aeronautical Univ. lUniversity of Rochester lEötvös Loránd University lSan Jose State University lUniversity of Florida lUniv. of Sannio at Benevento, lGerman/British Collaboration for and Univ. of Salerno the Detection of Gravitational Waves lUniversity of Sheffield lUniversity of Glasgow lUniversity of Southampton lGoddard Space Flight Center lSoutheastern Louisiana Univ. lLeibniz Universität Hannover lSouthern Univ. and A&M College lHobart & William Smith Colleges lStanford University lInst. of Applied Physics of the lUniversity of Strathclyde Russian Academy of Sciences lSyracuse University lPolish Academy of Sciences lUniv. of Texas at Austin lIndia Inter-University Centre lUniv. of Texas at Brownsville for Astronomy and Astrophysics lTrinity University lLouisiana State University lUniversitat de les Illes Balears lLouisiana Tech University lUniv. of Massachusetts Amherst lLoyola University New Orleans lUniversity of Western Australia lUniversity of Maryland lUniv. of Wisconsin-Milwaukee lMax Planck Institute for lWashington State University Gravitational Physics lUniversity of Washington Advanced LIGO

x10 better amplitude sensitivity ⇒ x1000 rate=(reach)3 ⇒ 1 day of Advanced LIGO » 1 year of Initial LIGO !

25 26 What is so Advanced?

Parameter LIGO Advanced LIGO Stored Laser Power 20 kW 800 kW Mirror Mass 10 kg 40 kg Power-recycled Dual-recycled Fabry- Interferometer Fabry-Perot arm Perot arm cavity To p o lo g y cavity Michelson Michelson GW Readout Method RF heterodyne DC homodyne Tunable, better than Optimal Strain 3 x 10-23 / rHz 5 x 10-24 / rHz in Sensitivity broadband Seismic Isolation f ~ 50 Hz f ~ 10 Hz Performance low low Mirror Suspensions Single Pendulum Quadruple pendulum 27 Advanced Virgo Similar scope to AdLIGO

Larger mirrors

Improved coatings

Higher laser power

DC read-out

Julien Marque Rencontres de Moriond 28 Stefan Hild Plans of GEO

29 Stefan Hild GEO HF § Emphasize high frequencies--length less important § Pioneer advanced techniques for other large interferometers § Tuned signal recycling and squeezing

30 KAGRA

3 km baseline

Utilizes cryogenic mirrors (sapphire)

Construction at an underground site (Kamioka mine)

Two parallel interferometers installed in a common vacuum envelope

Suspension pointKazuaki interferometer Kuroda for the TAMA/CLIO/LCGT Collaboration 31 LCGT

Conceptual Design SAS: 3 stage anti- vibration system with Vacuum is common inverted pendulum

Radiation outer shield

SPI auxiliary mirror Heat links start from this stage to inner radiation shield Sapphire fiber suspending main mirror

Main mirror

32 Overview'of'KAGRA

• KAGRA'science' • Characteris4c'features' – Direct'detec4on'of'GW' – Underground'at'Kamioka' in'one'year'observa4on' – Cryogenic'mirror – Opening'GW'astronomy' • World'wide'network' NASA'Photo KAGRA'enhances'sky'coverage'!

20K'sapphire'mirror

CQG'28'(2011)'125023'B.F.'Schutz VibraAon#IsolaAon #Main#SAS:##13m#tall# 2#stages#of#floor# • 19#standard#filters# have#been#built#and# delivered:#f GAS#filters on# # •# Six#out#of#11#pre: isolator#top#filters#ve# # # •# Prototypes#of#a# complete#chain t,#standard#filter,# bo@om#filter#and#opAcal# payload#have#been# completed#and#are# under#tests#in#Japan Ul#mate(design(sensi#vity(of(KAGRA This(sensi#vity(achieves(167(Mpc(for(( coalescence(GW(of(1.4(Ms(NSB. Duty%factor:%>%80%% Expected%event%rate% 20kg(test(mass(at(20(K( +14 Q1 9.8 Q6.6 yr Suspension(of(Q=108( Bulk(Q(of(mirror(108( 400kW(cavity(power( Q(of(coa#ng:(104( DC(read(out( ET Baseline Concept

§ Underground location » Reduce seismic noise » Reduce gravity gradient noise » Low frequency suspensions § Cryogenic § Overall beam tube length ~ 30km § Possibly different geometry

36 Einstein Gravitational-Wave Telescope (ET)

from Harald Lück 37