simulations for future ground based gw detectors gwadw 2010 kyoto, japan

Simulations for Future Ground Simulations for Future Ground Based GW DetectorsBased GW Detectors

GWADW 2010GWADW 2010

Kyoto, JapanKyoto, Japan

Matthew Evans, GWDAW 2010Matthew Evans, GWDAW 2010

What do we need simulations for What do we need simulations for anyway?anyway?

Optical SystemOptical SystemQuantum noisesQuantum noisesControl (length, alignment, thermal)Control (length, alignment, thermal)

Mechanical SystemMechanical SystemDisplacement noises (thermal, seismic, …)Displacement noises (thermal, seismic, …)Actuation of opticsActuation of optics

ElectronicsElectronicsSensing noises, actuation noise, …Sensing noises, actuation noise, …


Tools used for iLIGOTools used for iLIGO

TWIDDLE: frequency domainTWIDDLE: frequency domain SMAC: time domainSMAC: time domain FFT code: spatialFFT code: spatial SimulinkSimulink


Tools used for aLIGOTools used for aLIGO(~11 years later)(~11 years later)

Optickle: frequency (radiation pressure)Optickle: frequency (radiation pressure) E2E: time (modular)E2E: time (modular) SIS: space (faster, more flexible)SIS: space (faster, more flexible) ……


Establishing a code baseEstablishing a code base

It may be that it is natural to repeat the It may be that it is natural to repeat the same development many times, with a same development many times, with a small improvement each timesmall improvement each time

This can be useful as writing a simulation This can be useful as writing a simulation is a great way to learnis a great way to learn

Development process may be facilitated Development process may be facilitated by a well established code base and by a well established code base and documentationdocumentation


New simulations,New simulations,or new simulators?or new simulators?

Currently we have few expertsCurrently we have few expertsVery busy applying simulationsVery busy applying simulations Little time to write documentationLittle time to write documentation Little time to train othersLittle time to train others (with the result that we have few experts…)(with the result that we have few experts…)

Note to simulation writersNote to simulation writersYour time, effort and code will be forgottenYour time, effort and code will be forgotten If you document and/or train it will not be If you document and/or train it will not be

wastedwasted


What do we have?What do we have?What do we lack?What do we lack?

We have the basics covered, with one We have the basics covered, with one simulation or another.simulation or another.

We lack simulations which naturally We lack simulations which naturally include some combined effectsinclude some combined effectsExample: parametric instabilities should arise Example: parametric instabilities should arise

naturally in a full opto-mechanical modelnaturally in a full opto-mechanical model Do we need an all-inclusive simulation?Do we need an all-inclusive simulation?

Is such a thing practical or even desirable?Is such a thing practical or even desirable?


Simulations for 3Simulations for 3rdrd

Generation ProblemsGeneration Problems Optical SystemOptical System

Quantum noisesQuantum noisesComputed analytically by smart peopleComputed analytically by smart peopleCan be calculated with OptickleCan be calculated with Optickle… … but we need a system which aids designbut we need a system which aids design

Mechanical SystemMechanical SystemNon-linear processes (creek, creep, …)Non-linear processes (creek, creep, …)Thermal effects and noiseThermal effects and noise

Finite mass, multi-coating, stress-optic, …Finite mass, multi-coating, stress-optic, …Cryogenics, heat flow, material interfaces, …Cryogenics, heat flow, material interfaces, …



Generation ProblemsGeneration Problems Example… heat flow… noise?Example… heat flow… noise?



Generation ProblemsGeneration Problems Opto-mechanical SystemOpto-mechanical System

Suspension point interferometers, limited by Suspension point interferometers, limited by mechanical cross-couplingsmechanical cross-couplings

Xylophones which share mechanical partsXylophones which share mechanical parts Gravity GradientsGravity Gradients

In complex, non-uniform, geological areasIn complex, non-uniform, geological areas In large structures (e.g., super-dome)In large structures (e.g., super-dome)Cancellation with sensor arrayCancellation with sensor array



Generation ProblemsGeneration Problems Thermal noise limited seismic sensorsThermal noise limited seismic sensors

Super seismometersSuper seismometersTiltometers for 1mHz-1Hz bandTiltometers for 1mHz-1Hz band

ParticularsParticularsResidual gas noise (squeeze films)Residual gas noise (squeeze films)Charging noise, including surroundingsCharging noise, including surroundingsParametric InstabilitiesParametric Instabilities

… … many other things …many other things …


The path aheadThe path ahead

Fill gaps with dedicated codes which can Fill gaps with dedicated codes which can be incorporated into more comprehensive be incorporated into more comprehensive models as neededmodels as needed

Focus on making current capabilities easy Focus on making current capabilities easy to use, understand and extendto use, understand and extendDocumentation, examples, good codeDocumentation, examples, good codeAim for more users than authorsAim for more users than authorsOverlapping simulations will always existOverlapping simulations will always exist Let’s make sure they get better with timeLet’s make sure they get better with time


Enjoy Kyoto!Enjoy Kyoto!

simulations for future ground based gw detectors gwadw 2010 kyoto, japan

Documents

matthew evans

time slide

documentation slide

flexible slide

simulations little time

new simulations

spatial simulink slide

sensor array slide