LIGO-G1300800

Opening the Gravitational Wave WindowGabriela González

Louisiana State UniversityLSC spokesperson

For the LIGO Scientific Collaboration and the Virgo Collaboration

LIGO Livingston Observatory,Louisiana, USA

LIGO Hanford ObservatoryWashington, USA

Virgo detector, Cascina, Italy

LIGO-G13008002

Gravitational waves

Gravitational waves are quadrupolar distortions of distances between freely falling masses. They are

produced by time-varying mass quadrupoles.

€

Gμν = 8πGc 4 Tμν (= 0 in vacuum)

gμν =η μν + hμν

€

h =ΔLL

LIGO-G1300800

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The GW Detector Network 2005-2010

GEO600LIGO Hanford

LIGO Livingston

Virgo

LIGO-G13008004

LIGO Scientific Collaboration

• 900+ members, 86+ institutions, 17 countries

https://www.zeemaps.com/map?group=245330 roster.ligo.org

LIGO-G1300800

LIGO Detectors 2009-10 (S6)

5

Stra

in (1

/√H

z)

LIGO-G1300800

LIGO Detectors 2009-10 (S6)

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Find all LSC results and publications in www.ligo.org - science tab

Crab pulsar (NASA, Chandra Observatory)

?

Stra

in (1

/√H

z)

NASA, WMAP

LIGO-G13008007

LIGO-Virgo detectors 2005-2011atlasofthe universe.com

LIGO-G1300800

Some interesting results 2005-2011

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atlasofthe universe.comGRB070201

Astrophys. J. 681 (2008) 1419

GW100916Phys. Rev D85 (2012) 082002

LIGO-G13008009

Sept 16, 2010: “Big Dog event”

http://ligo.org/news/blind-injection.phpYou can get (and listen to!) the detector data and other details: http://ligo.org/science/GW100916/

False alarm rate ~1/7000 yrs!

Phys. Rev D85 (2012) 082002

LIGO-G130080010

Some other LVC Results 2005-2011Upper limit on GW stochastic background

Nature 460 (2009) 990

Upper limit on GW energy emitted by generic sources at 10 kpc

Phys. Rev. D 81 (2010) 102001

Upper limits on GW emissions from Crab and Vela pulsars

(X-ray: NASA/CXC/Univ of Toronto/M.Durant et al;

Optical: DSS/Davide De Martin)

NASA/CXC/ASU/J Hester et al. (Chandra); NASA/HST/ASU/J Hester et al. (Hubble)

Astrophys. J. 722 (2010) 1504Astrophys. J. 737 (2011) 93

Quantum-enhanced sensitivity!

LIGO-G1300800

Advanced LIGO

Now under construction: Advanced LIGO

~10 times better than initial LIGO , lower frequencies in bandInstallation in progress, going very well!

Coincident “lock” in ~2014, science runs starting in 2015 with increasing sensitivity to follow.

LIGO-G1300800

1212

The GW Detector Network~2016

GEO600-hfAdvanced LIGO

Hanford

Advanced LIGO Livingston

Advanced Virgo

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In progress: Advanced LIGO

Vacuum system – same as initial LIGO

US NSF funding for Advanced LIGO: 2008-2015.

Advanced

LIGO

LIGO-G1300800

Advanced LIGO construction (aLIGO) started 1Apr2008

Major technological differences between LIGO and Advanced LIGO

Initial Interferometers

Advanced Interferometers

Open up wider band

ReshapeNoise

Advanced interferometrySignal recycling

Active vibration isolation systems

High power laser (180W)

40kg

Quadruple pendulum:Silica optics, welded tosilica suspension fibers

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LIGO-G1300800

Initial vs Advanced LIGO

Lasers become more powerful: 10W 200 W

Advanced

LIGO

LIGO-G1300800

Initial vs Advanced LIGO

Seismic isolation goes from passive to active.

Advanced

LIGO

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Initial vs Advanced LIGO10 kg test masses on simple pendulums become 40 kg monolithic suspensions in quadruple pendulums, with better quality optics

40 kg silica test

mass

parallel reaction chain for control

actuation

Advanced

LIGO

LIGO-G130080018

More on Adv LIGO: LIGO magazine in www.ligo.org

LIGO-G1300800

Detection Rates

Neutron Star Binaries:Initial LIGO:

Average BNS reach ~15 Mpc rate ~1/50yrs

Advanced LIGO: ~ 200 Mpc “Realistic rate” ~ 40/year (but can be 0.4-

400)

Other binary systems:

NS-BH: 0.004/yr 10/yrBH-BH: 0.007/yr 20/yr

Class. Quant. Grav. 27, 173001 (2010)

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Advanced

LIGO

LIGO-G1300800

2020

The GW Detector Network~2016

GEO60Advanced LIGO

Hanford

Advanced LIGO Livingston

Advanced Virgo

LIGO-G130080021

Coming soon near you:Advanced GW Detectors running!

arXiv:1304.0670

LIGO-G130080022

• Mostly (but not all) robotic wide-field optical telescopes Many of them used for following up GRBs and/or hunting for supernovae

• Nine event candidates followed up by at least one scope• Astron Astrophys 539 (2012) A124• Astron Astrophys 541 (2012) A155

X-ray and UV/Optical

Radio

Multi-messenger astronomy2010 (initial detectors)

LIGO-G1300800

2323

The GW Detector Network~2020

GEO600Advanced LIGO

Hanford

Advanced LIGO Livingston

Advanced Virgo

LIGO-India

KAGRA

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BNS Merger Localization: Hanford-Livingston-Virgo

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3 site networkx denotes blind spots

S. Fairhurst, “Improved source localization with LIGO India”, arXiv:1205.6611v1

90% localization ellipses for face-on BNS sources at 160 Mpc.

LIGO-G1300800

BNS Localization: Hanford-Livingston-Virgo-India

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4 site network

S. Fairhurst, “Improved source localization with LIGO India”, arXiv:1205.6611v1

LIGO-G1300800

BNS Localization: Hanford-Livingston-Virgo-India-KAGRA

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5 site network:Slightly better localization,but also better sensitivity and duty cycle!

S. Fairhurst, “Improved source localization with LIGO India”, arXiv:1205.6611v1

90% localization ellipses for face-on BNS sources at 160 Mpc.

LIGO-G130080027

Multi messenger astronomy with Advanced Detectors

Two eras (dcc.ligo.org, LIGO-M1200055):• Now: The LSC and Virgo will partner with astronomers to carry out an

inclusive observing campaign for potentially interesting GW triggers, with MoUs to ensure coordination and confidentiality of the information. They are open to all requests from interested astronomers or astronomy projects which want to become partners through signing an MoU.

• Later: After the published discovery of gravitational waves with data from LSC and/or Virgo detectors, both the LSC and Virgo will begin releasing especially significant triggers promptly to the entire scientific community to enable a wider range of follow-up observations.

Also: LIGO data will become public after 2 yrs, with 6 month cadence, after we enter the “observational era” (dcc.ligo.org, M1000066)

LIGO-G130080028

Call for interest in EM counterparts to GW candidates

60+ responses including 400+ interested people!

LIGO-G130080029

Gravitational waves are coming!

www.ligo.org