Talk:List of gravitational wave observations

Table entries/organizations

Despite WP:CRYSTALBALL, We might want to rethink entries/columns in the table. Several issues:

1. The columns seem tuned to black hole merger events. Most of the columns do not really make sense for likely future observations such as continuous sources, GW background, etc.
2. On the other hand, as a table of a binary merger events some properties are weighted more heavily (like energy) while being the least important.

Suggestions:

• It is probably a good idea (for the future) to have separate tables for different types of events: binary mergers, continuous sources, burst sources, etc. (For now we only need the first).
• In the table for binary mergers have separate columns for masses, spins, and nature of primary and secondary.
• Probably include the LVT(s) in the same table but note their speculative nature.

TR 20:09, 27 September 2016 (UTC)

I agree. I notice that the scholarly journals refer to these events as a "compact binary coalescence (CBC)". Perhaps that could be the name of a list page with links to the different tables. Fantasticawesome (talk) 04:23, 17 March 2018 (UTC)

Would it be appropriate to include Joseph Weber's claims that he (and the Gran Sasso National Labs in Italy) observed gravitational waves from Supernova 1987A as a "candidate event"?

As references, see [1], [2], etc.

69.140.36.53 (talk) 03:15, 30 September 2016 (UTC)

I do not think that that would be appropriate, as those claims are widely disputed.TR 07:48, 30 September 2016 (UTC)

Unit conversions in table

I think we should remove the unit conversions from the table. They add a lot of clutter making the table harder to read. We can add a note to the column heading with conversions to other relevant units? As this involves a rather large change to the table, I'd rather get some feedback before being WP:BOLD about it.TR 08:36, 29 September 2017 (UTC)

"Remnant" for a merger?

I know that "remnant" is the term used to describe the collapsed object left behind by a supernovae explosion. But, does it also fit for the product of a collapsed object merger, in which only a small fraction of the mass is lost? WolfmanSF (talk) 14:44, 29 September 2017 (UTC)

This is the terminology that is used in for example all LIGO produced "fact sheets" (e.g. [3]). The use of this terminology becomes more obvious when you start looking binary neutron star mergers, where besides GWs some amount of matter may be ejected from the system at merger.TR 14:51, 29 September 2017 (UTC)

Spin

I removed the "spin" data from the table, as there was no information in, or near, the table to describe what this is, nor the units, e.g. Hz, rpm. If you put it back please state the units.
GW150914 0.68+0.05
−0.06 spin
GW151226 0.74+0.06
−0.06 spin
GM170104 0.64+0.09
−0.20 spin
GW170814 0.70+0.07
−0.05 spin
Nick Beeson (talk) 21:31, 2 October 2017 (UTC)

It's a dimensionless parameter that ranges from 0 to 1. WolfmanSF (talk) 02:46, 3 October 2017 (UTC)

Primary, Secondary, Remnant columns

Should these columns be split into individual columns for the mass, spin, and "nature" (e.g. black hole, white dwarf, neutron star, etc.)?TR 08:18, 3 October 2017 (UTC)

Size of table and wiki code

When we use a display screen 21" or larger this table looks good, but when using a smaller display it becomes ugly, can anyone help to use additional wiki code to make the table has a horizontal scroll bar when using a small dispaly to keep it size like when using 21" or larger display? Does it affect when using on a smartphone? Earthandmoon (talk) 08:37, 9 November 2017 (UTC)

I set a global minimum width for the table. Does this help?TR 18:51, 9 November 2017 (UTC)

It looks ok, thank you. Earthandmoon (talk) 03:43, 10 November 2017 (UTC)

Table entries without full articles?

LIGO-SC just put out a preprint on a new, low-mass BH merger ([[4]]). Would it be appropriate to add an entry to this table, without having the event name (GW170608) be a link to an article? Presumably this will become more relevant in the future, as statistics increase. Kelseymh (talk) 06:41, 16 November 2017 (UTC)

Makes sense to me, but a stub article looks quick to make as well. Tom Ruen (talk) 07:18, 16 November 2017 (UTC)

Chirp masses?

Should we add chirp masses to the table? The advantage is that they are much more accurately measurable. WolfmanSF (talk) 23:33, 16 November 2017 (UTC)

Wikidata Query / List of Gravitational Wave events

given that the list of gravitational wave events might somewhat grow in the future the following query might be useful: WikiData Query / List of Gravitational Wave events and wikipedia articles sorted by lang

# Find Gravitational wave events
# Created 2018-10-16 by Wolfgang Fahl BITPlan GmbH
#
# select the events
SELECT ?event ?catalogCode ?eventLabel ?lang ?article 
WHERE 
{
  # any subject
  # which is an instance of
  # https://www.wikidata.org/wiki/Property:P31
  # gravitational wave event
  # https://www.wikidata.org/wiki/Q24748034
  ?event wdt:P31 wd:Q24748034.
  OPTIONAL {
    ?event wdt:P528 ?catalogCode
  }
  SERVICE wikibase:label {               # ... include the labels
        bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en"
  }
  OPTIONAL {
      ?article schema:about ?event .
      ?article schema:inLanguage ?lang .
      FILTER (SUBSTR(str(?article), 1, 25) = concat("https://",?lang,".wikipedia.org/"))
  }
}
order by ?lang

--WolfgangFahl (talk) 11:34, 15 October 2018 (UTC)

Table entries for old events are outdated

The recent announcement also included updated values for all the previously announced events, usually slightly different from the previous values. Still more work to update everything. --mfb (talk) 11:08, 3 December 2018 (UTC)

Now updated. WolfmanSF (talk) 18:02, 6 December 2018 (UTC)

O3 candidates

There are too many... what a nice problem to have. Here is a neutron star merger candidate, and here is a list of all candidates (5 in the last 3 weeks). The information in that database is very rudimentary and likely to change with further analysis. I suggest to not include GraceDb candidates and wait for a proper analysis unless the candidates get significant media attention. --mfb (talk) 16:15, 25 April 2019 (UTC)

@Mfb: As the primary curator for those, what I've been doing is (by intention at least) only including events with a false alarm rate of less than 1 in 100 years, giving brief mention of events with a false alarm rate of 1-100 years, and ignoring sub-1-year-FAR objects unless there's some other notable quality. LIGO predicts that they'll be getting one every week or so, which has held quite true so far. Considering these events are virtually confirmed to exist- but the specifics haven't been hashed out yet- I'd say we should include them and, worst case scenario, we make a separate listing of preliminary GW reports until they can be formally reviewed in a paper. No point in holding off for weeks or months on something that's both in public accessibility and virtually confirmed to exist as a very first point of analysis. exoplanetaryscience (talk) 02:31, 26 April 2019 (UTC)

The main problem is not the question if these events are real (although we shouldn't neglect that: The false positive rate is purely from statistics, it doesn't include other causes). The problem is the poor knowledge about these events. We don't get much more than "we saw something", everything else is uncertain. --mfb (talk) 03:04, 26 April 2019 (UTC)

While I agree that that could potentially result in an overload of (non)information, I think that at the moment it's decently balanced and meaningful to list these. For the recent events, we have not only the fact that 'we saw something' but about where in the sky it is, what kind of object it probably came from, about how far away it is, and an indicator of whether that's something interesting or not. If this preliminary info weren't informational enough to be useful, then we wouldn't have just had a bunch of news outlets posting about the neutron star merger. exoplanetaryscience (talk) 20:51, 26 April 2019 (UTC)

See "unless the candidates get significant media attention". The GraceDB entries are primary sources meant for astronomers. If you think they absolutely have to be in the article put them in - I don't think it is a good idea but I won't remove them. --mfb (talk) 07:12, 27 April 2019 (UTC)

I think they should be here. I came here looking for exactly this. Fig (talk) 21:19, 27 April 2019 (UTC)

Looks like 0421 has been upgraded to 97% BBH... Fig (talk) 09:54, 4 May 2019 (UTC)

Primary vs secondary sourcing

I am concerned about basing an article largely on primary sources and whether your decisions on which reports to include count as original research or synthesis. I'm not going to take any action, as I don't see any conclusion being drawn, other than the interesting one that there is a lot going on. TomS TDotO (talk) 10:41, 4 May 2019 (UTC)

Correct me if I'm wrong, but I don't see what's wrong with using primary sources for an article if they're reliable and decently informative? exoplanetaryscience (talk) 19:56, 4 May 2019 (UTC)

WP:PSTS "Do not base an entire article on primary sources, and be cautious about basing large passages on them." WP:SYN "...do not combine different parts of one source to reach or imply a conclusion not explicitly stated by the source." I know that SYN does not exactly apply, for there is no conclusion stated. ANd I want to make it clear that I am not thinking of objecting, I'm just noting the topic. I am amazed at the large number and frequency of observatons. TomS TDotO (talk) 22:22, 4 May 2019 (UTC)

Since there is only one LIGO it’s perfectly obvious that all detections be will from their primary source, unless there is multi-messenger detection as in GW170817. The current frequency of detections, however, is exactly in line with theoretical predictions from multiple sources. Fig (talk) 08:11, 5 May 2019 (UTC)

WP:PRIMARY

"Policy: Unless restricted by another policy, primary sources that have been reputably published may be used in Wikipedia, but only with care, because it is easy to misuse them.[d] Any interpretation of primary source material requires a reliable secondary source for that interpretation. A primary source may only be used on Wikipedia to make straightforward, descriptive statements of facts that can be verified by any educated person with access to the primary source but without further, specialized knowledge. For example, an article about a novel may cite passages to describe the plot, but any interpretation needs a secondary source.

• Do not analyze, evaluate, interpret, or synthesize material found in a primary source yourself; instead, refer to reliable secondary sources that do so.

• Do not base an entire article on primary sources, and be cautious about basing large passages on them.

• Do not add unsourced material from your personal experience, because that would make Wikipedia a primary source of that material. Use extra caution when handling primary sources about living people; see WP:Biographies of living persons § Avoid misuse of primary sources, which is policy." TomS TDotO (talk) 17:08, 5 May 2019 (UTC)

This policy is less applicable to science than say, history or literature. Recent, ground-breaking scientific findings obviously need to be reported, and it could be a while before suitable secondary sources appear. WolfmanSF (talk) 17:26, 5 May 2019 (UTC)

The qualifier 'candidate' must be applied to all immediate claims for LVC triggers, with lapses in confirmatory discourse rampant throughout LIGO-Virgo social media and popular science articles during O3. Many non-astrophysical transients produce virtually identical waveforms as those assumed to be unique to GW events. No records of magnetometer or power mains fluctuations are presented by LVC, and their mention is avoided, despite that LIGO events are accompanied by unsettled magnetospheric-ionospheric conditions (substorms, particle injections, magnetospheric sawtooth events, unusual radio bursts, pulse-coupled global CG lightning mode).

Some non-rejected events still show a significant probability for terrestrial sources (the very fact of this ambiguity highlights the inexact and bias-prone nature of LIGO-Virgo phenomenology), and three (as of June 4, 2019 12:57 UTC) claimed events have been retracted (including the first reported event for O3, S190405ar, which was not effectively publicized as being a rejected event until the arrival of a second non-rejected candidate, S190412m. In addition to S190405ar, S190518bb and S190524q have been retracted. All three are considered terrestrial noise, yet met criteria for consideration as candidate events. https://gracedb.ligo.org/latest/ False alarm rate is considered virtually meaningless by LIGO, which calls into question yet again the neutrality of any motivation for nearly immediate updates for LVC events on Wikipedia - unprecedented in science, and potentially dangerous/misleading.

Systematic error likely affects parameters, as extremes in values for consecutive events for DL suggest: S190602aq FAR 1/T=16.673 yrs, DL 797±238 S190524q FAR 1/T=4.5458 yrs, [event retracted], DL 192±101 S190521g FAR 1/T=8.3367 yrs, furthest claimed LIGO DL 3931±953 S190519bj FAR 1/T=5.56 yrs, former furthest claimed LIGO DL 3154±791 S190518bb FAR 1/T=3.16 yrs, closest claimed DL [event retracted] 28±15 S190517h FAR 1/T=13.35 yrs, former furthest LIGO DL 2950±1038 S190426c FAR 1/T=1.63 yrs, DL 377±100 S190421ar FAR 1/T=2.13 yrs; DL 1628±535 S190405ar FAR 6756.4/T=1 yrs, [event retracted] DL 268±129. Fulguritics 13:16, 4 June 2019 (UTC)

Fulguritics I have seen your posts on Twitter responding to LIGO announcements. You are one of the tiny number of people who think that LIGO is not detecting gravitational waves, and your entire online presence seems geared towards this. As such you are promoting fringe science and therefore I do not believe your tagging of this page as NPOV is valid or itself impartial. This page is not the page for fighting ideological battles on gravitational wave detectors. If you want to do that you should do it at the LIGO talk page...but good luck finding any independent references for the ideas you are promoting.

I believe the NPOV tag should be removed from this page. Fig (talk) 08:56, 7 July 2019 (UTC)

At this point, NPOV tag should remain until independent assessment of O3 LIGO results is published, and realize that no peer-reviewed O3 LIGO publications yet exist. LIGO-Virgo would be unprecedented in their unchecked confidence given that this Wikipedia table is updated as soon as *candidate* signals are presented by LVC collab. here https://gracedb.ligo.org/. This page implies certainty. Candidates are uncertain. Therefore, the presentation of non-reviewed possible false alarms as equivalent to past, peer reviewed findings does not qualify as an unbiased approach.

There is no ideology behind appropriate criticism. One admits their inability to distinguish ideology from criticism when they sacrifice their logical consistency and disinterest. Any beliefs or personal sentiments regarding the capability of LIGO-Virgo to detect gravitational waves has no bearing on the applicability of the NPOV tag, as technically, we adhere to standards that LIGO has no control over. Opposition to equivocal criteria by which LIGO findings are vetted is not a fringe view. My role is purely to apply due controls to an experiment that has demonstrated no concern to publicize magnetometer data, power mains data, and other key onsite control system datasets that are essential to the rejection of LIGO signals, and must be maintained during findings regardless of Bayesian priors. LEt me remind one that LIGO noise floor in the best case for N=28 LIGO-Virgo triggers is 3 orders of magnitude above desired signal, and Numerical Relativity templates do not exist for all candidate transient signals.

There are many "independent" references and new studies in multiple geophysical/heliophysical contexts that are producing findings about the solar-terrestrial neighborhood and its energetic behavior that lead one to think twice regarding instantaneous acceptance of LIGO-Virgo signals, especially as three claimed triggers for O3 have been retracted as noise, and the distinctions between any number of upchirp-producing sources, most terrestrial, that trigger the LVC network are purely statistical, with rejection due to non-presence/"independence" of particular classes of "glitches." Most LIGO signals are accompanied by glitches, and their bearing on LIGO-Virgo signal rejection is weighted by apparent"network SNR." Fulguritics (Fulguritics) 11:49, 7 July 2019 (UTC)

Since these are labelled "preliminary" it should not instill certainty as you suggest. But perhaps we could have en extra sentence in the O3 introduction to say that the observations have not yet been published in a peer reviewed journal yet. Graeme Bartlett (talk) 12:04, 7 July 2019 (UTC)

Table formatting

How about colourising the primary and secondary ‘type’ cells - according to content - as with the o1, o2 and o3 runs? Fig (talk) 19:15, 12 May 2019 (UTC)

@Fig wright: Done, how does that look? exoplanetaryscience (talk) 22:33, 13 May 2019 (UTC)

@Exoplanetaryscience: Good - nice one :) Fig (talk) 13:04, 14 May 2019 (UTC)

Moved O3 alerts to separate table

I moved the O3 alerts to a separate table. This are fundamentally different in nature than the confirmed events. They have not (yet) been subjected to the same detailed analysis as the confirmed events. Their primary function is to allow EM astronomers to follow up on events if they wish. As such the provided information is tailored such that they can make an informed decision on which events events to follow up. Added advantage is that we can now change the columns that we have for these alerts. Things like components and final masses and spins will not be published for alerts during O3, hence we don't need those columns for these events. Instead we can have dedicated columns for the information that is provided (such as the FAR).(TR 10:17, 5 July 2019 (UTC))

S190728q

GraceDB, 52% mass gap, 34% binary black hole, 14% neutron star black hole, IceCube has seen a neutrino that would be consistent with this event. Forbes article, search for S190728q to skip the irrelevant parts before. --mfb (talk) 11:42, 30 July 2019 (UTC)

S190814bv

S190814bv looks exciting - predicted to be almost certainly a "mass gap" observation. Tayste (edits) 23:52, 14 August 2019 (UTC)

Almost certainly NS/BH, an update changed the expectation completely. --mfb (talk) 04:51, 16 August 2019 (UTC)

S190828j/S190828l

Just 21 minutes apart, very similar sky localization. Let's look if a reliable source discusses potential gravitational lensing. --mfb (talk) 15:52, 28 August 2019 (UTC)

Very unlikely. News article, Blog article (Dutch). --mfb (talk) 01:01, 31 August 2019 (UTC)

2030s

Was informed in a talk yesterday that if things develop as planned, by the 2030s we'll get ~10,000 NS/NS and ~100,000 BH/BH merger detections per annum. WolfmanSF (talk) 20:22, 5 November 2019 (UTC)

By whom? In which talk? And on a substantial note: How are supposed to measure these? --MGChecker (talk) 21:35, 5 November 2019 (UTC)

You can find Samaya Nissanke's talk (starting at 3h 15', with that prediction made at 3h 35') here. WolfmanSF (talk) 22:15, 5 November 2019 (UTC)

Just like Lists of stars, we'll have to restrict lists to the notable ones. Gaia has data about nearly two billion objects, mainly stars and galaxies. --mfb (talk) 01:09, 6 November 2019 (UTC)

Well, at some point, we will have to think about this. However, at the moment we do not have to many observations yet. Let's wait how much is left from O3 after we have actual observations confirmed by the collaboration instead of some mere candidates. --MGChecker (talk) 15:44, 6 November 2019 (UTC)

what are "events" and "superevents"?

I think these terms have a technical meaning here and should be defined. "Event" is used in the "Nomenclature" section without definition and in a figure caption; "superevent" is used in a figure caption. For "superevent", I find a definition at ligo.org but it is too technical and I'm not sure I would get it right. Are events something "in the data" or"the real thing"? --Qcomp (talk) 21:27, 12 November 2019 (UTC)

The "superevent" nomenclature is particular to how things are reported in graceDB, and does not have any deeper physical meaning. (It is just a way of distinguishing different types of entries in the database. )TR 16:33, 13 November 2019 (UTC)

So is the difference between the "events" in the figure for O1 and O2 and the "superevents" for O3 that the latter are not yet confirmed? Would it be correct to extend the first sentence of the Nomenclature-paragraph to read

Gravitational wave events are named starting with the prefix GW, while observations that trigger a event alert but have not (yet) been confirmed are named starting with the prefix S and sometimes referred to as "superevents".

? I think the article text should explain the technical terms (including those used in the figures) so that lay readers (like myself) know what to make of them.--Qcomp (talk) 13:18, 14 November 2019 (UTC)

Apparently you haven't noticed that the offending term has been removed from the article. WolfmanSF (talk) 20:29, 14 November 2019 (UTC)

no, it is still in the figure (the one displaying "LIGO & Virgo O3 Superevents" - that was where I stumbled across the term in the first place... --Qcomp (talk) 20:36, 14 November 2019 (UTC)

S200114f

@Exoplanetaryscience: where did you get its comment from? A three digit number for the frequency makes no sense if the whole event was only one period long. Its frequency spectrum must be extremely broad if that time is correct. --mfb (talk) 04:33, 14 January 2020 (UTC)

The report is from graceDB's initial.xml file: https://gracedb.ligo.org/apiweb/superevents/S200114f/files/S200114f-3-Initial.xml,0 I'm a bit skeptical myself of the cited frequency, but they seem to know what they're doing. I don't think I could confidently change the significant digits of the frequency without seeing any info on LIGO-Virgo's temporal resolution. exoplanetaryscience (talk) 04:54, 14 January 2020 (UTC)

That's the central frequency, a signal that short can't have a frequency that well-defined, and the database just reports the best fit with a silly number of digits in all cases. I rounded it to produce a useful statement. --mfb (talk) 20:56, 14 January 2020 (UTC)

Column ordering

Ideally, the Massgap column in O3 should come before the BH/BH column to preserve the order of increasing mass. I realise that’s a lot of work though... Fig (talk) 10:08, 19 January 2020 (UTC)

controversies

There are lots of controversies about the so-called discoveries of so-called gravitational waves. They should be discussed here. — Preceding unsigned comment added by 178.122.67.240 (talk) 00:19, 12 February 2020 (UTC)

Please add new sections at the bottom, not at the top. There isn't really a controversy in science. There is the science, and then there are a few people who can't accept it (most of the time for ideological reasons, as far as I can see) and make up stuff. --mfb (talk) 06:39, 12 February 2020 (UTC)

Events from non-LIGO analyses

At least two groups (in Princton, and the former LIGO group in Hannover) have re-analyzed the O1 and O2 data, finding a few more high significance events. How should we include them in this list?TR 22:54, 12 March 2020 (UTC)

One option might be to treat them the same, except adding a note to the publication date indicating the event was found in a later re-analysis. WolfmanSF (talk) 23:12, 12 March 2020 (UTC)

As a test, I've added the one extra event for O1.TR 09:35, 13 March 2020 (UTC)

For reference some of the relevant references:

Hanover group:

• 1811.01921
• 1910.05331

Princeton group:

• 1902.10341
• 1904.07214
• 1910.09528

TR 08:51, 13 March 2020 (UTC)

I'm somewhat hesitant to put all of these in as observations due to their hesitant nature- LTV151012 was held from the list until last year because the 2.4% chance of a false signal wasn't considered strong enough evidence on its own. I propose we make a separate list of marginal detections whose existence is unconfirmed. exoplanetaryscience (talk) 22:16, 24 March 2020 (UTC)

Or we could add a false alarm rate column to the table. WolfmanSF (talk) 22:29, 24 March 2020 (UTC)

The last two of these preprints haven't been published either. Headbomb {t · c · p · b} 22:31, 24 March 2020 (UTC)

What do you guys think of this edit I made? exoplanetaryscience (talk) 00:22, 25 March 2020 (UTC)

I'm not sure I see much value in listing events with less than a 50% probability of being astrophysical in origin. Is there something interesting about them I'm missing? WolfmanSF (talk) 07:45, 25 March 2020 (UTC)

Well I thought about it this way: say you've got 7 different events with a 90% chance of being terrestrial noise. Statistically, one of them is probably a bona fide event. Sure, a lot of them have pretty low probabilities even below 10%, but nevertheless the fact that a possible signal was detected makes them worthy of at least a footnote to me. exoplanetaryscience (talk) 18:11, 25 March 2020 (UTC)

Given that we will be drowning in detections fairly soon, my preference would be to focus on the most meaningful events. WolfmanSF (talk) 23:33, 25 March 2020 (UTC)

@TimothyRias:@Headbomb: what do you think? >50% p_astro detections only? exoplanetaryscience (talk) 20:45, 26 March 2020 (UTC)

I would suggest to limit it to only events that have been identified as "real" events by at least two sources. I.e. for O1+02 this would be the LIGO sources plus GW170121, GW170304, and GW170727.TR 14:53, 27 March 2020 (UTC)

I'd personally just make a tally of what's been reported in peer-reviewed venues, e.g. "In addition, 42 sources are considered potential observations at a lesser significance" or something. But I don't have any strong feelings on this. Headbomb {t · c · p · b} 20:05, 27 March 2020 (UTC)

probability

candidate events with a probability of near 1 to be terrestrial should not be listed here. i think a fair threshold would be either .9 or .5. this should not be a comprehensive academic review, and there are plenty of detections by now to try to be limiting the number of low relevancy events. — Preceding unsigned comment added by 2601:602:9200:1310:F86F:2D18:D52:FD1A (talk) 10:07, 4 June 2020 (UTC)

Published 03 events

I think we should move the published events from O3 to a separate table, either the same one used for O1/O2, or a new one. One of the many reasons is that the current table with public triggers does not have columns for listing the inferred source parameters.TR 18:25, 4 June 2020 (UTC)