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 `-----'`--' `--' `------' `--'   `--' `---' `--''--'     `----'  `--'   `----'  `---'  `----'                                                                                             

Description

The CAGMon etude is a study version of CAGMon that evaluates the dependence between the primary and auxiliary channels.

Project goal

The goal of this project is to find a systematic way of identifying the abnormal glitches in the gravitational-wave data using various methods of correlation analysis. Usually, the community such as LIGO, Virgo, and KAGRA uses a conventional way of finding glitches in auxiliary channels of the detector - Klein-Welle, Omicron, Ordered Veto Lists, etc. However, some different ways can be possible to find and monitor them in a (quasi-) realtime. Also, the method can point out which channel is responsible for the found glitch. In this project, we study its possible to apply three different correlation methods - maximal information coefficient, Pearson's correlation coefficient, and Kendall's tau coefficient - in the gravitational wave data from the KAGRA detector.

Participants

• John.J Oh (NIMS)
• Young-Min Kim (UNIST)
• Pil-Jong Jung (NIMS)

Methods and Frameworks

Maximal Information Coefficient (MIC)

the Maximal Information coefficient(MIC) of a set D of two-variable data with sample size n and grid less than B(n) is given by

\[ MIC(D)=\underset{xy<B(n)}{\max}{\left\{ \frac{I^{*}(D,x,y)}{\log \min \left\{x,y \right\}} \right \}} \],

where \[\omega(1)<B(n)\le O(n^{1-\epsilon}) \] for some \[ 0<\epsilon<1 \]

Pearson's Correlation Coefficient (PCC)

Pearson Correlation Coefficient(PCC) is a statistic that explains the amount of variance accounted for in the relationship between two (or more) variables by \[ R=} \],

where \[ \overline{X} \] and \[ \overline{Y} \] are the mean of X and Y, respectively

Kendall's tau Coefficient

Kendall’s tau with a random samples n of observations from two variables measures the strength of the relationship between two ordinal level variables by

\[ \tau =\frac{c-d} \],

where c is the number of concordant pairs, and d is the number of discordant pairs

Flow chart

Code development

GitHub

TBA

Code versions

1. CAGMon Etude Alpha
   • for the basic test and evaluation of the LASSO regression method developed by LIGO
   • reproduced original CAGMon methods and idea
2. CAGMon Etude Beta
   • added coefficient trend plots with LASSO beta, coherence, MIC, PCC, and Kendall's tau
3. CAGMon Etude Delta
   • fixed a critical problem that sucked enormous memory when it used the matplotlib module
4. CAGMon Etude Eta
   • fixed minor issues
   • added the range limitation of stride
5. CAGMon Etude Flat (current version)
   • fixed minor issues and optimized scripts
   • added the script of HTML summary page
   • added coefficient distribution plots
6. CAGMon Etude Octave (development version)
   • remove some processes that make Time-series and Scatter plots. Even though it required tremendous memory, this information is not useful
   • adjust HTML code
   • fixed minor issues and optimized scripts

Series of scripts

• Agrement.py
  • the script gathered functions the model required
• Melody.py
  • the script to calcutate each coefficient and to save trend data as csv
• Conchord.py
  • the script to make plots
• Echo.py
  • the script to save the result as HTML web page
• CAGMonEtude{Version}.py
  • the script to run each script

User guide

• How to use CAGMon

Needs of code development

• Fundamental critarian or guideline of the stride and its data-size
• Daily running on KAGRA

Exemplary results

1. Earthquake effects during O3GK

• Datetime: 19 April 2020 20:39 UTC
• Purpose
  • Test to run CAGMon algorithm with a remarkable event
  • To figure out the cause of lock-loss in KAGRA
• Results

  • stride 5 seconds Summary page

  • stride 20 seconds Summary page

  • stride 30 seconds Summary page

2. Skim through all obs-segments of O3GK

• Purpose
  • Test for calculation time and required resources with all observation segments during O3GK
  • To figure out trigger events or abnormal behaviors
• Results

  Date	GPS time	Stride	Sample rate	Data size	Summary page link	Remarks
  April 7	1270287158 - 1270328032	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 8	1270339218 - 1270425618					Full Data is unavailable in the KISTI cluster
  April 9	1270425618 - 1270510167	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 10	1270513160 - 1270596544	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 11	1270598418 - 1270683904	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 12	1270684818 - 1270762046	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 14	1270909686 - 1270937768	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 15	1270945288 - 1271017582					GRB200415 (08:48:05 UTC) / Full Data is unavailable in the KISTI cluster
  April 16	1271030433 - 1271112809	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 17	1271119833 - 1271186507	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 18	1271227441 - 1271288128	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 19	1271289618 - 1271364033	600s	16Hz	about 10,000	summary page
  		300s	32Hz	about 10,000	summary page
  April 20	1271377409 - 1271460608					GRB200420A (2:32:58 UTC) / Full Data is unavailable in the KISTI cluster

3. With iKAGRA hardware injection data

• Event
  • Phenomenon: the strain channel and seismometer channels in iKAGRA had a high correlation during the hardware injection test
  • Cause: still unknown
  • Hypothesis: the glitches have relatively the same behavior as the vacuum rotary pump

  • More detail analysis: hveto brief Report for K1 and KGWG Face-to-Face Meeting

• Purpose
  • To verify whether this model senses injected signals and abnormal glitches
  • To test noise resistance and data-size limitation
• Results

  Stride	Sample sata	Data size	Dada length	Summary page link
  10s	512Hz	about 5,000	about 12m	summary page
  10s	1024Hz	about 10,000	about 12m	summary page
  10s	2048Hz	about 20,000	about 12m	summary page
  10s	3072Hz	about 30,000	about 12m	summary page
  10s	4096Hz	about 40,000	about 12m	summary page
  2s	4096Hz	about 8,000	about 12m	summary page
  5s	4096Hz	about 20,000	about 12m	summary page
  60s	128Hz	about 7,500	whole iKAGRA data	summary page
  150s	64Hz	about 10,000	whole iKAGRA data	summary page
  300s	64Hz	about 20,000	whole iKAGRA data	summary page
  600s	16Hz	about 10,000	whole iKAGRA data	summary page

Beyond

References

Presentation materials

JGW-G2112481-v1

Papers

Science.1518; Detecting Novel Associations in Large Data Sets