A Total of Ten Black Hole Collisions and a Neutron Star Collision Have Been Detected

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The LIGO and Virgo gravitational wave observatories report four more gravitation wave detections. The total number of gravitational waves we have every detected is now 11.

Ten were caused by black hole collisions and one was by neutron stars colliding.

The current small amount of evidence suggests :

* black holes may have merged more frequently earlier in the universe’s history
* fewer collisions are now involving black holes bigger than about 50 times the sun’s mass

Both gravitation wave detectors will be shutdown until next spring to upgrade their equipment. The improvements should allow the detection of three times the volume of gravitational wave detections.

Abstract – Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs

Arxiv – GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs.

We present the results from three gravitational-wave searches for coalescing compact binaries with component masses above 1M⊙ during the first and second observing runs of the Advanced gravitational-wave detector network. During the first observing run (O1), from September 12th, 2015 to January 19th, 2016, gravitational waves from three binary black hole mergers were detected. The second observing run (O2), which ran from November 30th, 2016 to August 25th, 2017, saw the first detection of gravitational waves from a binary neutron star inspiral, in addition to the observation of gravitational waves from a total of seven binary black hole mergers, four of which we report here for the first time: GW170729, GW170809, GW170818 and GW170823. For all significant gravitational-wave events, we provide estimates of the source properties. The detected binary black holes have total masses between 18.6+3.1−0.7M⊙, and 85.1+15.6−10.9M⊙, and range in distance between 320+120−110 Mpc and 2750+1350−1320 Mpc. No neutron star – black hole mergers were detected. In addition to highly significant gravitational-wave events, we also provide a list of marginal event candidates with an estimated false alarm rate less than 1 per 30 days. From these results over the first two observing runs, which include approximately one gravitational-wave detection per 15 days of data searched, we infer merger rates at the 90% confidence intervals of 110 – 3840 Gpc−3y−1 for binary neutron stars and 9.7 – 101 Gpc−3y−1 for binary black holes, and determine a neutron star – black hole merger rate 90% upper limit of 610 Gpc−3y−1.

12 thoughts on “A Total of Ten Black Hole Collisions and a Neutron Star Collision Have Been Detected”

  1. LOL.  

    Assuming that the Relentless-Spell-Corrector got the better of your message, I believe you meant “Large Hadron Collider” … but in any case LOL. 

    We puny Earthlings have little to fear about being sucked up in so-called black holes. 
    First … and foremost … is that they’re dâhmned rare, as astronomers have determined. 

    At this juncture, there are thought to be 3 kinds: most numerous kind, left over when extra massive stars exhaust their fuel and collapse due to gravitational pressure (these are the “small” or “stellar scale” type), those (still rather numerous) that act as consolidation nuclei at the centers of globular clusters, micro galaxies, and probably quasars, and the much rarer supergiants, will millions-to-billions of 1-Sol masses that are at the center of virtually every elliptical and most spiral galaxies. 

    Sounds like a lot? 

    The closest 7 known black hole candidates are 

    A0620–00-V616 (3,000 Ly), 
    Cygnus X–1 (6,000 Ly),
    V404-Cygni (7,800 Ly),
    GRO J0422+32 (8,100 Ly),
    Cygnus X–3 (11,100 Ly),
    GRO J1655 (11,900 Ly),
    4U1543–475 (29,700 Ly). 

    That would be 7 in a volume of ⁴⁄₃π(29,700)³ → 109 TRILLION cubic light years. 

    Needless to say, since the INFLUENCE of a black hole is measured in single-digit AUs (distance of Earth to Sun), there are 3×10²⁸ AU³ of space, in which there are 7 black holes. It really isn’t like we’re going to run into any of them. Ever. 

    Hope that helps.
    GoatGuy

  4. Hi I am wondering about the logic of black holes and gravity. Is it possible to extract the earth from black holes before sucking the earth by large Hadrian collided or by bombarded the black holes.feedback back is congenial.

  5. So it is. Using Chrome’s developer tools, I can see that the <sup> and <sub> tags have had their style reset by the WP theme Brian uses…

  8. The detected binary black holes have total masses between 18.6±8% M⊙¹, and 85.1+−15% M⊙, and range in distance between 320±115 Mpc and 2750±1333 Mpc. No (neutron star – black hole) mergers were detected. In addition to highly significant gravitational-wave events, we also provide a list of marginal event candidates with an estimated false alarm rate less than 1 per 30 days. From these results over the first two observing runs, which include approximately one gravitational-wave detection per 15 days of data searched, we infer merger rates at the 90% confidence intervals of 110 – 3840 per Gpc³ per year for binary neutron stars and 9.7 – 101 per Gpc³ per year for binary black holes, and determine a neutron star – black hole merger rate 90% upper limit of 610 per Gpc³ per year.

    ¹ M⊙ = mass of Sol, our star
    ² Gpc = giga parsec.
    ³ parsec = 3.26 light years

    Therefore a cubic gigaparsec is a HUGE volume of space, to be sure. But how big?

    1 giga( unit³ ) = 10⁹ unit³.  
    Take the cube root of that, and that’s 10³ or 1,000 units-on-a-side.  

    Well, 1,000 parsec × 3.26 Ly/pc = 3,260 Ly on a side. That’s tiny. Can’t be right.  

    More likely the induction is:

    1 (giga unit)³ = 10²⁷ unit³
    1,000,000,000 parsec × 3.26 Ly/kc = 3,260,000,000 Ly. Which is

    1,326 MLy ÷ 13,700 MLy ≈ 10% of scale-size of Universe. 

    Not sure this helps, but what the heck…

  9. Any ideas on how to do that tweaking?
    Perhaps writers could use ^ to indicate ‘raise to the power of’. It is a fairly standard use that doesn’t get messed up of web pages.

  10. tweak your browser, I see nicely -3 and -1 as upper indices (powers), i.e. spatial and temporal density, as you say

  12. Can the astronomers in the house unpack 110 – 3840 Gpc – 3 y – 1 for us? I see gigaparsecs and years, but I can’t correlate those to rates of mergers, which ought to have dimensions of inverse time times inverse volume ([Gpc · y]³?)

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