Einstein Telescope: seismic and GGN studiesgw.icrr.u-tokyo.ac.jp/gwadw2010/program/2010_GWADW_Beker.pdf · Mark Beker, Nikhef Amsterdam on behalf of the ET design study team GWADW

Mark Beker, Nikhef Amsterdamon behalf of the ET design study teamGWADW 2010, Kyoto, Japan17 May 2010

Einstein Telescope: seismic and GGN studies

[email protected]

Tuesday, May 18, 2010

mailto:[email protected]

mailto:[email protected]

Gravity gradient noise may limit Einstein Telescope sensitivity at low frequencies

2

Seismic noise spectrum - displacement

ASD

[m/rt

Hz]

Frequency [Hz]

GGN calculationsHigh/Low noise model

1e-12

1e-11

1e-10

1e-09

1e-08

1e-07

1e-06

1e-05

0.1 1 10

ET noise budget

10 0 10 1 10 210 26

10 25

10 24

10 23

10 22

10 21

10 20

10 19

Frequency [Hz]

Quantum noiseSeismic noiseNewtonian noiseCoating Brownian noiseCoating thermo-optic noiseSubstrate Brownian noiseExcess gasTotal noiseAdvanced VirgoET target

Strain

[1/

Hz]

Assumptions: - Surface detector - Isotropic body pressure waves - Seismic spectrum: (5 nm/ f2 )/√Hz

Saulson’s model prediction of GGNET-B requirement 0.1 nm/√HzET-C requirement (0.1 nm/ f2 )/√Hz

[S. Hild et. al. arXiv.org:0810.0604][P. R. Saulson, Phys. Rev. D, 30, 1984]



2


ASD

[m/rt

Hz]

Frequency [Hz]


1e-12

1e-11

1e-10

1e-09

1e-08

1e-07

1e-06

1e-05

0.1 1 10

ET noise budget

10 0 10 1 10 210 26

10 25

10 24

10 23

10 22

10 21

10 20

10 19

Frequency [Hz]


Strain

[1/

Hz]






2


ASD

[m/rt

Hz]

Frequency [Hz]


1e-12

1e-11

1e-10

1e-09

1e-08

1e-07

1e-06

1e-05

0.1 1 10

ET noise budget

10 0 10 1 10 210 26

10 25

10 24

10 23

10 22

10 21

10 20

10 19

Frequency [Hz]


Strain

[1/

Hz]





ET sensitivity requirements corresponds to a seismic acceleration PSD of 3x10-17 (m2/s4) f4/Hz

3

PSD

[(m

2/s4

)/Hz]

Frequency [Hz]

ET-B requirementsHigh/Low noise model

1e-19 1e-18 1e-17 1e-16 1e-15 1e-14 1e-13 1e-12 1e-11 1e-10 1e-09

0.1 1 10

Seismic noise spectrum - acceleration

ASD

[m/H

z]

Frequency [Hz]


1e-12

1e-11

1e-10

1e-09

1e-08

1e-07

1e-06

1e-05

0.1 1 10



Can a suitably seismically quiet location be found to satisfy this requirement?

4

PSD

[(m

2/s4

)/Hz]

Frequency [Hz]


1e-19 1e-18 1e-17 1e-16 1e-15 1e-14 1e-13 1e-12 1e-11 1e-10 1e-09

0.1 1 10


Seismic measurements have been done throughout Europe to classify underground locations

• 2 Trillium 240 seismometers• Broadband mHz - 30 Hz

• Hard-rock tile

• Insulation cover

• Data acquisition systems• LabView readout through 18 bit DAQ card

• Low noise amplifier

5Tuesday, May 18, 2010



• Hard-rock tile







• Hard-rock tile







• Hard-rock tile







• Hard-rock tile





6

5/14/10 6:30 AMEinstein Telescope project - Google Maps

Page 1 of 5http://maps.google.com/maps/ms?f=q&source=s_q&hl=en&geocode=…5ff&ll=52.643063,18.017578&spn=29.791782,68.466797&z=4&pw=1

ETseismic locations0 views - PublicCreated on May 13 - Updated < 1 minute agoBy mbekerRate this map - Write a comment

SITE CHARACTERISTICS:- Decommissioned lead mine.- Local geology is andesite (wave speed equal to granite)

GYÖNGYÖSOROSZI MINE

Data collected from these sites

Measurements still to be carried out at these sites


6








Underground data available from these sites


6








5/16/10 10:52 AMInotani Station, Japan - Google Maps

Page 1 of 2http://maps.google.com/

Address

AND, Basarsoft, Geocentre Consulting, Mapabc, PPWK, Tele Atlas, Transnavicom, Europa Technologies, Google, INEGI, LeadDog Consulting, MapLink -

ETseismic locations

SITE CHARACTERISTICS:- Decommissioned lead mine.- Local geology is andesite (wave speed equal to granite)- Longest mine drift is approximately 3km.- Mine is at 330m depth.- Current seismic station is at approx 50m.- Local population density 75/km2 (Gyongyosoroszi 21.39km2)- Distance to sea or ocean is approximately 500km.SITE MEASUREMENTS:01/04/2010 UNTIL 07/04/2010Seismic info:https://workarea.et-gw.eu/et/general/public-slides/sites/Hungary.pdf


View in Google Earth Print Send Link Get Directions My Maps

To see all the details that are visible on thescreen,use the "Print" link next to the map.

2 Seismometers in Homestake mine, SD



6










Address


ETseismic locations








Address

©2010 Google - Map data ©2010 AND, Europa Technologies, Geocentre Consulting, Mapabc, ZENRIN, SK M&C -

SITE CHARACTERISTICS:- Decommissioned salt mine (largest salt mine in Europe)- Local geology is andesite.- Already contains some large caverns.- Current depth of seismic station is unknown.- Depth of mine is at a few hundreds of metres.- Local population density is 180/km2 (Slanic 40km2).- Distance to sea or ocean is 300km.SITE MEASUREMENTS:08/04/2010 UNTIL 14/04/2010 Seismic info:https://workarea.et-gw.eu/et/general/public-slides/sites/Romania-SLANIC-PRAHOVA.pdf

Sl!nic

Baksan Neutrino Observatory




Thanks to:Dr. Kazuaki KurodaDr. Uchiyama TakashiDr. Osamu MiyakawaDr. Shinji Miyoki


6










Address


ETseismic locations








Address

©2010 Google - Map data ©2010 AND, Europa Technologies, Geocentre Consulting, Mapabc, ZENRIN, SK M&C -

SITE CHARACTERISTICS:- Decommissioned salt mine (largest salt mine in Europe)- Local geology is andesite.- Already contains some large caverns.- Current depth of seismic station is unknown.- Depth of mine is at a few hundreds of metres.- Local population density is 180/km2 (Slanic 40km2).- Distance to sea or ocean is 300km.SITE MEASUREMENTS:08/04/2010 UNTIL 14/04/2010 Seismic info:https://workarea.et-gw.eu/et/general/public-slides/sites/Romania-SLANIC-PRAHOVA.pdf

Sl!nic

Baksan Neutrino Observatory




Thanks to:Dr. Kazuaki KurodaDr. Uchiyama TakashiDr. Osamu MiyakawaDr. Shinji Miyoki

Surface seismic data from > 200 sites (Orfeus network)


7

Characterization of sites is done using spectral variation plots of half hour averages

The Netherlands


7

Characterization of sites is done using spectral variation plots of half hour averages

The NetherlandsSpain - Lab. Sub. Canfranc


Locations in Hungary, France and Spain have shown to be within ET-B requirements > 2 Hz

8

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

1e-11

0.1 1 10Frequency [Hz]

Mode from half hour PSDs N

PSD

[m /s

/Hz

]2

4

RomaniaHolland

HungarySpain - LSC

France - LSMHigh/Low noise model

ET-B req.



8

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

1e-11



PSD

[m /s

/Hz]

24

RomaniaHolland

HungarySpain - LSC


ET-B req.

Error bars indicate 90 and 10%

occurrence levels



8

10 m2000 m200 m400 m800 m

Depth

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

1e-11



PSD

[m /s

/Hz]

24

RomaniaHolland

HungarySpain - LSC


ET-B req.


occurrence levels



8

10 m2000 m200 m400 m800 m

Depth

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

1e-11



PSD

[m /s

/Hz]

24

RomaniaHolland

HungarySpain - LSC


ET-B req.


occurrence levels

Romania was a working salt mine


SuSa Mo

9

Seismic noise at 1 - 20 Hz is dominated by anthropogenic activity

Earthquake, Solomon Islands, Magnitude 6.8 Mining blast


SuSa Mo

9

Seismic noise at 1 - 20 Hz is dominated by anthropogenic activity

Earthquake, Solomon Islands, Magnitude 6.8 Mining blast

Spectrogram Slanic salt mine Romania


Given that underground seismicity is achievable, what about the contribution of surface waves to GGN?

10

ET-B

ET-C

[G. Cella et. al. Class.Quan.Grav 2010]

Frequency [Hz]

Strain / √H

z



• G. Cella (ET workshop 2009)• Propagating surface wave modes only (distant sources)

• Significant reductions with depth

• Smaller wavelength = higher reductions

10

ET-B

ET-C


Frequency [Hz]

Strain / √H

z






10

Surface

ET-B

ET-C


Frequency [Hz]

Strain / √H

z






10

Surface-10 m

ET-B

ET-C


Frequency [Hz]

Strain / √H

z






10

Surface-10 m-50 m

ET-B

ET-C


Frequency [Hz]

Strain / √H

z






10

Surface-10 m-50 m-100 m

ET-B

ET-C


Frequency [Hz]

Strain / √H

z






10

Surface-10 m-50 m-100 m-150 m

ET-B

ET-C


Frequency [Hz]

Strain / √H

z






• Still left with self-generated local noise sources

• Local impulse excitations don’t profit from a reduction in depth

• Prediction and subtraction methods

10

Surface-10 m-50 m-100 m-150 m

ET-B

ET-C


Frequency [Hz]

Strain / √H

z


Finite element models can be used to get a better understanding of local source effects

• FE models have been shown to accurately reproduce seismic surface and body waves from an excitation

• Investigate surface / body wave effects• FE models can be developed to include inhomogeneities and complex geologies

• Used to test GGN subtraction algorithms


GGN simulations done on homogeneous media show strong contributions from local sources

12

5e-14

1e-13

1.5e-13

2e-13

2.5e-13

3e-13

3.5e-13

4e-13

0 0.5 1 1.5 2

Max

imum

acc

eler

atio

n [m

/s2 ]

Depth, z/cP

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

0.1 1 10

Ampl

itude

Spe

ctru

m [m

/s2 ]

Frequency [Hz]

z/cP = 0z/cP = 0.5

z/cP = 1z/cP = 1.5

-1e-13

-5e-14

0

5e-14

1e-13

0 1 2 3 4 5 6

Time [s]

z/cP=1.5

TotalSurface

Bulk

-1e-13

-5e-14

0

5e-14

1e-13

1.5e-13

2e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

Time [s]

z/cP=1 m

-4e-13

-3e-13

-2e-13

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

z/cP=0.5 m

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

QS2Clay3 z/cP=0 m

5e-14

1e-13

1.5e-13

2e-13

2.5e-13

3e-13

3.5e-13

4e-13

0 0.5 1 1.5 2

Max

imum

acc

eler

atio

n [m

/s2 ]

Depth, z/cP

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

0.1 1 10

Ampl

itude

Spe

ctru

m [m

/s2 ]

Frequency [Hz]

z/cP = 0z/cP = 0.5

z/cP = 1z/cP = 1.5

-1e-13

-5e-14

0

5e-14

1e-13

0 1 2 3 4 5 6

Time [s]

z/cP=1.5

TotalSurface

Bulk

-1e-13

-5e-14

0

5e-14

1e-13

1.5e-13

2e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

Time [s]

z/cP=1 m

-4e-13

-3e-13

-2e-13

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

z/cP=0.5 m

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

QS2Clay3 z/cP=0 m

z = 0 m

z = 800 m = λP



12

Rayleigh wave arrives at surface detector

S-wave arrives at sub-ter. detector

5e-14

1e-13

1.5e-13

2e-13

2.5e-13

3e-13

3.5e-13

4e-13

0 0.5 1 1.5 2

Max

imum

acc

eler

atio

n [m

/s2 ]

Depth, z/cP

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

0.1 1 10

Ampl

itude

Spe

ctru

m [m

/s2 ]

Frequency [Hz]

z/cP = 0z/cP = 0.5

z/cP = 1z/cP = 1.5

-1e-13

-5e-14

0

5e-14

1e-13

0 1 2 3 4 5 6

Time [s]

z/cP=1.5

TotalSurface

Bulk

-1e-13

-5e-14

0

5e-14

1e-13

1.5e-13

2e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

Time [s]

z/cP=1 m

-4e-13

-3e-13

-2e-13

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

z/cP=0.5 m

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

QS2Clay3 z/cP=0 m

5e-14

1e-13

1.5e-13

2e-13

2.5e-13

3e-13

3.5e-13

4e-13

0 0.5 1 1.5 2

Max

imum

acc

eler

atio

n [m

/s2 ]

Depth, z/cP

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

0.1 1 10

Ampl

itude

Spe

ctru

m [m

/s2 ]

Frequency [Hz]

z/cP = 0z/cP = 0.5

z/cP = 1z/cP = 1.5

-1e-13

-5e-14

0

5e-14

1e-13

0 1 2 3 4 5 6

Time [s]

z/cP=1.5

TotalSurface

Bulk

-1e-13

-5e-14

0

5e-14

1e-13

1.5e-13

2e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

Time [s]

z/cP=1 m

-4e-13

-3e-13

-2e-13

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

z/cP=0.5 m

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

QS2Clay3 z/cP=0 m

z = 0 m

z = 800 m = λP



12

Rayleigh wave arrives at surface detector

S-wave arrives at sub-ter. detector

5e-14

1e-13

1.5e-13

2e-13

2.5e-13

3e-13

3.5e-13

4e-13

0 0.5 1 1.5 2

Max

imum

acc

eler

atio

n [m

/s2 ]

Depth, z/cP

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

0.1 1 10

Ampl

itude

Spe

ctru

m [m

/s2 ]

Frequency [Hz]

z/cP = 0z/cP = 0.5

z/cP = 1z/cP = 1.5

-1e-13

-5e-14

0

5e-14

1e-13

0 1 2 3 4 5 6

Time [s]

z/cP=1.5

TotalSurface

Bulk

-1e-13

-5e-14

0

5e-14

1e-13

1.5e-13

2e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

Time [s]

z/cP=1 m

-4e-13

-3e-13

-2e-13

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

z/cP=0.5 m

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

QS2Clay3 z/cP=0 m

5e-14

1e-13

1.5e-13

2e-13

2.5e-13

3e-13

3.5e-13

4e-13

0 0.5 1 1.5 2

Max

imum

acc

eler

atio

n [m

/s2 ]

Depth, z/cP

1e-17

1e-16

1e-15

1e-14

1e-13

1e-12

0.1 1 10

Ampl

itude

Spe

ctru

m [m

/s2 ]

Frequency [Hz]

z/cP = 0z/cP = 0.5

z/cP = 1z/cP = 1.5

-1e-13

-5e-14

0

5e-14

1e-13

0 1 2 3 4 5 6

Time [s]

z/cP=1.5

TotalSurface

Bulk

-1e-13

-5e-14

0

5e-14

1e-13

1.5e-13

2e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

Time [s]

z/cP=1 m

-4e-13

-3e-13

-2e-13

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

z/cP=0.5 m

-1e-13

0

1e-13

2e-13

3e-13

4e-13

0 1 2 3 4 5 6

Acce

lera

tion

[m/s

2 ]

QS2Clay3 z/cP=0 m

z = 0 m

z = 800 m = λP


13

Clay:λP = 800 mλS = 462 mρ = 2000 kg/m3ν = 0.25

Limestone:λP = 2200 mλS = 1270 mρ = 2500 kg/m3ν = 0.25

Harmonic excitations only benefit from small reduction factors


13





13



0.1

1

100 1000

Redu

ction

facto

r

Depth [m]

Clay 1Hz FEA/FitClay 4Hz FEA/Fit

Granite 1Hz FEA/FitGranite 4Hz FEA/Fit

GGN re

duction factor

Depth [m]

GGNmax(z)/GGNmax(0)GGN at depth / GGN at surface

λP=800 m λP=2200 m


100 1000

1

0.1

LimestoneClay


Adaptive filter algorithms can be used to predict and subtract GGN

• Use secondary sensors to measure the density perturbations around the detector.

• Create models that estimatethe sensor to test mass impulse responses.

• Use adaptive filter techniques to estimate and reduce GGN

14

NewtonianNoise TFhnn

x(n) d(n) e(n)

e(n) = d(n) -

!+

-

Update algorithm

Digital filtersystemw

d(n)^

d(n)^"w

Seismic signalNewtonian

noise

Estimated Newtonian

noise

GW signal


GGN due to harmonic local source is used to test filter effectiveness

15

0

0

1 2 3 4 5 6Time [s]

Finite Element Analysis GGN - Harmonic excitation

GGNxExcitation

Loca

l acc

elerat

ion am

plitud

e [Ar

b. Un

its]


GGN due to harmonic local source is used to test filter effectiveness

15

0

0

1 2 3 4 5 6Time [s]

Finite Element Analysis GGN - Harmonic excitation

GGNxExcitation

Loca

l acc

elerat

ion am

plitud

e [Ar

b. Un

its]


Results of simple filtering algorithm show a reduction of 1.5 orders of magnitude

16

Time domain performance of the Wiener filter

GGN !xfiltered estimateSubracted channel

Loca

l acc

elerat

ion am

plitud

e [Ar

b. Un

its]

0 1 2 3 4 5 6Time [s]


Future work

• Seismic measurements

• Finish preliminary characterization of sites in Europe

• Data analysis

• FE GGN models

• Multiple uncorrelated sources

• Various geologies

• Cavity size and shape

• GGN filtering

• Optimizing filter coefficients

• Determine requirements for seismic array (seismometer density and positions)


Conclusions

• The ET-B seismic noise requirement can be obtained at various locations in Europe.

• ET-C requirement will be more challenging

• Surface wave effects reduce with depth• Local excitations will still be a source of GGN• Finite element models used to better understand these effects

• Can be reduced using adaptive filtering techniques

• Care must be taken when considering placement of infrastructure (advice committee)




Documents

Einstein Telescope: seismic and GGN studiesgw.icrr.u-tokyo.ac.jp/gwadw2010/program/2010_GWADW_Beker.pdf · Mark Beker, Nikhef Amsterdam on behalf of the ET design study team GWADW