{ "id": 256059, "title": "why i dont find f=60hz in the data? ", "url": "/competitions/g2net-gravitational-wave-detection/discussion/256059", "author_name": "", "post_date": "2021-07-30T15:53:10.201994300Z", "votes": 5, "comment_count": 5, "views": 0, "content": "

Seems like there are large amplitude noise coming from the power line:

\n
\n

High amplitude noise features are also present in
\n the data at certain frequencies, including lines due to the AC power grid (harmonics of 60 Hz
\n in the U.S. and 50 Hz in Europe)

\n
\n

based on the LIGO noise paper: https://iopscience.iop.org/article/10.1088/1361-6382/ab685e/pdf
\nhowever, I tried notch on the time series and compared before and after, there seems like little to no changes, am I missing something here?

", "messages": [ { "id": "1405231", "postDate": "07/30/2021 15:53:10", "content": "

Seems like there are large amplitude noise coming from the power line:

\n
\n

High amplitude noise features are also present in
\n the data at certain frequencies, including lines due to the AC power grid (harmonics of 60 Hz
\n in the U.S. and 50 Hz in Europe)

\n
\n

based on the LIGO noise paper: https://iopscience.iop.org/article/10.1088/1361-6382/ab685e/pdf
\nhowever, I tried notch on the time series and compared before and after, there seems like little to no changes, am I missing something here?

", "rawMarkdown": "Seems like there are large amplitude noise coming from the power line:\n>High amplitude noise features are also present in\nthe data at certain frequencies, including lines due to the AC power grid (harmonics of 60 Hz\nin the U.S. and 50 Hz in Europe)\n\nbased on the LIGO noise paper: https://iopscience.iop.org/article/10.1088/1361-6382/ab685e/pdf\nhowever, I tried `notch` on the time series and compared before and after, there seems like little to no changes, am I missing something here?", "votes": null }, { "id": "1406645", "postDate": "08/01/2021 03:38:43", "content": "

Try dissecting this ID: 2ea66bcb54 which has GW. I tried getting rid of 60Hz harmonics and it works pretty well for me

", "rawMarkdown": "Try dissecting this ID: 2ea66bcb54 which has GW. I tried getting rid of 60Hz harmonics and it works pretty well for me", "votes": null }, { "id": "1407062", "postDate": "08/01/2021 13:33:40", "content": "

What do you mean by \"it works pretty well for me\" ?

", "rawMarkdown": "What do you mean by \"it works pretty well for me\" ?", "votes": null }, { "id": "1407141", "postDate": "08/01/2021 14:59:34", "content": "

Sorry for being vague. lol

\n

I tried different low, high, and bandpass, and notch filters and could visually see changes to the FFT plot compared to the original signal as GW is strong for ID-2ea66bcb54

\n

Reference:

\n
    \n
  1. https://gwpy.github.io/docs/stable/examples/timeseries/filter.html
    2. \n
  2. https://gwpy.github.io/docs/stable/examples/timeseries/whiten.html
    3. \n
  3. https://gwpy.github.io/docs/stable/examples/signal/gw150914.html
    4. \n
  4. https://colab.research.google.com/github/gwastro/pycbc-tutorials/blob/master/tutorial/2_VisualizationSignalProcessing.ipynb
    5. \n
", "rawMarkdown": "Sorry for being vague. lol\n\nI tried different low, high, and bandpass, and notch filters and could visually see changes to the FFT plot compared to the original signal as GW is strong for ID-2ea66bcb54\n\nReference:\n1. https://gwpy.github.io/docs/stable/examples/timeseries/filter.html\n2. https://gwpy.github.io/docs/stable/examples/timeseries/whiten.html\n3. https://gwpy.github.io/docs/stable/examples/signal/gw150914.html\n4. https://colab.research.google.com/github/gwastro/pycbc-tutorials/blob/master/tutorial/2_VisualizationSignalProcessing.ipynb", "votes": null }, { "id": "1407525", "postDate": "08/02/2021 01:01:04", "content": "

hmm there would be a difference if we notch out the 60hz for sure, but my question was I didn't see 60hz being large amplitude in our signal in the first place, in my asd plot, the 60hz didn't show a large spike comparing to some of the tutorials out there, for example the one you shared (point 4.), in their asd plot, 60hz can be clearly see as a large spike, but I don't see this in ours e.g. in 2ea66bcb54 you gave.

", "rawMarkdown": "hmm there would be a difference if we notch out the 60hz for sure, but my question was I didn't see 60hz being large amplitude in our signal in the first place, in my asd plot, the 60hz didn't show a large spike comparing to some of the tutorials out there, for example the one you shared (point 4.), in their asd plot, 60hz can be clearly see as a large spike, but I don't see this in ours e.g. in 2ea66bcb54 you gave.", "votes": null }, { "id": "1561292", "postDate": "10/27/2021 13:12:41", "content": "

Hey All,

\n

Thank you all for taking part in our competition. The participation has been overwhelmingly positive. We are currently conducting a survey to gauge the demographic and outreach achieved. Kindly spare 2min and fill in this survey https://forms.gle/QP9L16niPexozyhu5.

\n

Thank you all,

\n

Regards,
\nChris

", "rawMarkdown": "Hey All,\n\nThank you all for taking part in our competition. The participation has been overwhelmingly positive. We are currently conducting a survey to gauge the demographic and outreach achieved. Kindly spare 2min and fill in this survey https://forms.gle/QP9L16niPexozyhu5.\n\nThank you all,\n\nRegards,\nChris", "votes": null } ], "comments": [ { "id": 1406645, "author_name": "harshpatel1692", "author_url": "", "post_date": "08/01/2021 03:38:43", "content": "

Try dissecting this ID: 2ea66bcb54 which has GW. I tried getting rid of 60Hz harmonics and it works pretty well for me

", "votes": null, "replies": [ { "id": 1407062, "author_name": "cpmpml", "author_url": "", "post_date": "08/01/2021 13:33:40", "content": "

What do you mean by \"it works pretty well for me\" ?

", "votes": null, "replies": [] }, { "id": 1407141, "author_name": "harshpatel1692", "author_url": "", "post_date": "08/01/2021 14:59:34", "content": "

Sorry for being vague. lol

\n

I tried different low, high, and bandpass, and notch filters and could visually see changes to the FFT plot compared to the original signal as GW is strong for ID-2ea66bcb54

\n

Reference:

\n
    \n
  1. https://gwpy.github.io/docs/stable/examples/timeseries/filter.html
    2. \n
  2. https://gwpy.github.io/docs/stable/examples/timeseries/whiten.html
    3. \n
  3. https://gwpy.github.io/docs/stable/examples/signal/gw150914.html
    4. \n
  4. https://colab.research.google.com/github/gwastro/pycbc-tutorials/blob/master/tutorial/2_VisualizationSignalProcessing.ipynb
    5. \n
", "votes": null, "replies": [] }, { "id": 1407525, "author_name": "samshipengs", "author_url": "", "post_date": "08/02/2021 01:01:04", "content": "

hmm there would be a difference if we notch out the 60hz for sure, but my question was I didn't see 60hz being large amplitude in our signal in the first place, in my asd plot, the 60hz didn't show a large spike comparing to some of the tutorials out there, for example the one you shared (point 4.), in their asd plot, 60hz can be clearly see as a large spike, but I don't see this in ours e.g. in 2ea66bcb54 you gave.

", "votes": null, "replies": [] } ] }, { "id": 1561292, "author_name": "zerafachris", "author_url": "", "post_date": "10/27/2021 13:12:41", "content": "

Hey All,

\n

Thank you all for taking part in our competition. The participation has been overwhelmingly positive. We are currently conducting a survey to gauge the demographic and outreach achieved. Kindly spare 2min and fill in this survey https://forms.gle/QP9L16niPexozyhu5.

\n

Thank you all,

\n

Regards,
\nChris

", "votes": null, "replies": [] } ], "raw_markdown_by_id": { "1405231": "Seems like there are large amplitude noise coming from the power line:\n>High amplitude noise features are also present in\nthe data at certain frequencies, including lines due to the AC power grid (harmonics of 60 Hz\nin the U.S. and 50 Hz in Europe)\n\nbased on the LIGO noise paper: https://iopscience.iop.org/article/10.1088/1361-6382/ab685e/pdf\nhowever, I tried `notch` on the time series and compared before and after, there seems like little to no changes, am I missing something here?", "1406645": "Try dissecting this ID: 2ea66bcb54 which has GW. I tried getting rid of 60Hz harmonics and it works pretty well for me", "1407062": "What do you mean by \"it works pretty well for me\" ?", "1407141": "Sorry for being vague. lol\n\nI tried different low, high, and bandpass, and notch filters and could visually see changes to the FFT plot compared to the original signal as GW is strong for ID-2ea66bcb54\n\nReference:\n1. https://gwpy.github.io/docs/stable/examples/timeseries/filter.html\n2. https://gwpy.github.io/docs/stable/examples/timeseries/whiten.html\n3. https://gwpy.github.io/docs/stable/examples/signal/gw150914.html\n4. https://colab.research.google.com/github/gwastro/pycbc-tutorials/blob/master/tutorial/2_VisualizationSignalProcessing.ipynb", "1407525": "hmm there would be a difference if we notch out the 60hz for sure, but my question was I didn't see 60hz being large amplitude in our signal in the first place, in my asd plot, the 60hz didn't show a large spike comparing to some of the tutorials out there, for example the one you shared (point 4.), in their asd plot, 60hz can be clearly see as a large spike, but I don't see this in ours e.g. in 2ea66bcb54 you gave.", "1561292": "Hey All,\n\nThank you all for taking part in our competition. The participation has been overwhelmingly positive. We are currently conducting a survey to gauge the demographic and outreach achieved. Kindly spare 2min and fill in this survey https://forms.gle/QP9L16niPexozyhu5.\n\nThank you all,\n\nRegards,\nChris" }, "source": "meta" }