Searching for correlations in global environmental noise Karl Wette, Susan Scott and Antony Searle ACIGA Data Analysis Centre for Gravitational Physics The Australian National University [email protected]
Dec 19, 2015
Searching for correlations in global environmental noiseKarl Wette, Susan Scott and Antony Searle
ACIGA Data AnalysisCentre for Gravitational PhysicsThe Australian National University
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 2
Outline
Global correlations impact global networks
Southern hemisphere monitoring station established
Data acquisition from LIGO, Virgo Software to handle datasets
approaching Tb
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 3
Global gravitational astronomy
Multiple observatories required to triangulate source and veto false alarms
Southern hemisphere detector could complete a global network
Confidence in results requires knowledge of correlated disturbances to detectors
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 4
Local environmental monitoring
In The ANU Gravitational Wave Research Facility Optical cleanroom on damped slab
(VRM, HPTF etc.) Not at Gingin, but still far from existing
observatories Three seismometers (XYZ)
Supplied by Dept. Earth Sciences, from the field
One down for repairs Tri-axial magnetometer (XYZ)
Off-the-shelf instrument Electrical supply voltage monitor
Locally built Australia has 60 Hz power grid
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 5
Local data acquisition
Outside clean-room Power supplies
Several supply different components, minimising cross-talk
Anti-aliasing filters GPS receiver
1 PPS signal Signal generator
2048 Hz locked to GPS NI ADC card
Sampling triggered by generator
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 6
Local data management
NI LabView software extended to write acquired channels directly to standard Frame files
Script uploads completed frames to ANUSF multi-terabyte Mass Data Storage System (MDSS)
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 7
Global data acquisition
Basic environmental channels are large 1 Gb, per day, per site
Important to download only needed channels, not files Use LIGOtools (getFrames) + LDAS to produce and
download an environmental monitoring RDS LIGO does not archive these channels outside science
runs, so this must be done in near real time Use Benoit’s goodwill
Data grid technologies Local work on extensions to permit distribution at
channel, not file level Future feasibility will depend on relative costs of internet
and physical (couriered tape or disk) transfer Part of major Australian data grid effort, with
astronomers and particle physicists
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 8
ACIGA Data Analysis Cluster
16 P4 processors 1 Tb RAID1 storage 14 Gb ECC RAM LDAS Data grid Environmental data
analysis
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 9
Pipeline
Accesses all data Highly parallel Runs on ACIGA Data
Analysis Cluster Produce spectrograms Automated detection of
unusual features Ensemble of statistical
tests
K Wette, S Scott, A Searle Searching for correlations in global environmental noise ACIGA Data Analysis 10
Future
UpgradeAU$10k this year for better acquisition systemPostdoc 2005-7 includes this project
AnalysisLong timescale coherencesCoherence bursts in spectrograms Impact on global astronomyVeto recommendations