# Is there a way to fetch Main strain channel data without noise or events?
**URL:** https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197
**Category:** Data Analysis
**Created:** [March 11, 2025, 11:07am UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197 "2025-03-11T11:07:00Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@Shan909](https://ask.igwn.org/u/Shan909)
#### Post date: [March 11, 2025, 11:07am UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197/1 "2025-03-11T11:07:00Z")
I want to fetch O3a run’s strain data that when the detector is in idle state as in when no astrophysical events and no noise from aux channels are detected. Is there any function within gwpy to fetch this or would I have to manually verify this with comparing noise timelines and event timelines?
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### Author:  [@jonah](https://ask.igwn.org/u/jonah)
#### Post date: [March 14, 2025, 10:46pm UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197/2 "2025-03-14T22:46:55Z")
There are a few different ways you could approach this.
To avoid times when there are astrophysical signals, you can start by avoiding times listed in the [GWTC-3 catalog](https://gwosc.org/eventapi/html/GWTC-3-confident/)
Times of “no noise” depends on your threshold for how much noise you can tolerate. One option is to use the [CAT-3 segment lists](https://gwosc.org/timeline/show/O3a_4KHZ_R1/H1_CBC_CAT3*L1_CBC_CAT3*V1_CBC_CAT3/1238166018/15811200/) to find times that pass all of the data quality checks. Alternatively, you could use the strain database information to find times when the BNS range is high.
There’s no method in gwpy that will do all of this automatically, but there are tools for handling segment lists that might help. Good luck!
> **[Data-quality segments - GWpy 3.0.12 documentation](https://gwpy.github.io/docs/stable/segments/)**
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### Author:  [@Shan909](https://ask.igwn.org/u/Shan909)
#### Post date: [March 17, 2025, 3:27pm UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197/3 "2025-03-17T15:27:21Z")
Thank you for the reference, I had forgotten about the CAT labels.
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### Author:  [@Julian](https://ask.igwn.org/u/Julian)
#### Post date: [March 19, 2025, 7:35pm UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197/4 "2025-03-19T19:35:39Z")
> **[GWTC\_cleaned](https://docs.google.com/spreadsheets/d/1ZbIIoxipV4Zf9I8xt-kp81JnM4QEjnjBzXeYt5YFCpM/edit?usp=sharing)**
>
> This Sheet is private
i have full CSV of cleaned data here ready to go, lmk if you have issues
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### Author:  [@Shan909](https://ask.igwn.org/u/Shan909)
#### Post date: [March 20, 2025, 10:09am UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197/5 "2025-03-20T10:09:50Z")
Thank you for this, ton of work reduced
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### Author:  [@Julian](https://ask.igwn.org/u/Julian)
#### Post date: [March 20, 2025, 5:51pm UTC](https://ask.igwn.org/t/is-there-a-way-to-fetch-main-strain-channel-data-without-noise-or-events/1197/6 "2025-03-20T17:51:23Z")
i have a few others, and CMBs for July and Nov 2024 temps cleaned