<p>The answer is no. KAGRA's first series of observations was in two parts, first from February 25 to March 10 and then from April 7 to April 2020, the latter a joint run performed in conjunction with the GEO600 detector. The sensitivity was fairly weak during this period, and as expected, no detections were found (<a href="https://arxiv.org/abs/2203.01270" rel="noreferrer">Abbott et al. 2022</a>). (In this case, &quot;fairly weak&quot; means that the maximum distance at which a neutron star-neutron star merger would be detectable was 600 kpc during the February/March run and 1 Mpc during the April run.)</p>
<p>LIGO and Virgo ended O3 on March 27, so they and KAGRA were only operating simultaneously during the first part of KAGRA's observations. By my count, of the O3 candidates released (<a href="https://arxiv.org/abs/2111.03606" rel="noreferrer">Abbott et al. 2021</a>), only four were detected on days when KAGRA was up and running. All were black hole-black hole coalescences with luminosity distances likely over 1 Gpc, nothing particularly easy for KAGRA to find - so again, not surprising that it didn't detect any of them.</p>

CC BY-SA 4.0
2022-04-17T21:10:21.960Z
2022-04-17T21:10:21.960Z
HDE 226868
<p><a href="https://en.wikipedia.org/wiki/KAGRA" rel="nofollow noreferrer">KAGRA</a> the Kamioka Gravitational Wave Detector and formerly the Large Scale Cryogenic Gravitational Wave Telescope (LCGT)</p>
<blockquote>
<p>...<strong>became operational on 25 February 2020</strong>, when it began data collection. It is Asia's first gravitational wave observatory, the first in the world built underground, and the first whose detector uses cryogenic mirrors. The design calls for an operational sensitivity equal to, or greater than, LIGO and Virgo. KAGRA is located in the Kamioka Observatory in Gifu Prefecture, Japan. The observatory specializes in the detection of neutrino, dark matter and gravitational waves, and possesses other important instruments, including Super Kamiokande, XMASS and NEWAGE.</p>
<p>The collaboration of LIGO, Virgo and KAGRA plans to start the next observation run (O4) in mid-December, 2022 (<strong>KAGRA ended its latest observation run on 21 April 2020; that was also the first observation run for KAGRA</strong>)</p>
</blockquote>
<p>There can be a coincidence in time even in the absence of a collaboration, so I'd like to ask:</p>
<p><strong>Question:</strong> Were there any gravitational wave coincidences between KAGRA and VIRGO and/or LIGO?</p>

<observational-astronomy><gravitational-waves>
Were there any gravitational wave coincidences between KAGRA and VIRGO and/or LIGO?
uhoh
# Were there any gravitational wave coincidences between KAGRA and VIRGO and/or LIGO?

(Asked by: username_0 on 2022-04-17)

[KAGRA](https://en.wikipedia.org/wiki/KAGRA) the Kamioka Gravitational Wave Detector and formerly the Large Scale Cryogenic Gravitational Wave Telescope (LCGT)

> ...**became operational on 25 February 2020**, when it began data collection. It is Asia's first gravitational wave observatory, the first in the world built underground, and the first whose detector uses cryogenic mirrors. The design calls for an operational sensitivity equal to, or greater than, LIGO and Virgo. KAGRA is located in the Kamioka Observatory in Gifu Prefecture, Japan. The observatory specializes in the detection of neutrino, dark matter and gravitational waves, and possesses other important instruments, including Super Kamiokande, XMASS and NEWAGE.
>
> The collaboration of LIGO, Virgo and KAGRA plans to start the next observation run (O4) in mid-December, 2022 (**KAGRA ended its latest observation run on 21 April 2020; that was also the first observation run for KAGRA**)

There can be a coincidence in time even in the absence of a collaboration, so I'd like to ask:

**Question:** Were there any gravitational wave coincidences between KAGRA and VIRGO and/or LIGO?

**Tags:** observational-astronomy, gravitational-waves

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## 1 answers

### Answer by username_1 on 2022-04-17. Score: 5

The answer is no. KAGRA's first series of observations was in two parts, first from February 25 to March 10 and then from April 7 to April 2020, the latter a joint run performed in conjunction with the GEO600 detector. The sensitivity was fairly weak during this period, and as expected, no detections were found ([Abbott et al. 2022](https://arxiv.org/abs/2203.01270)). (In this case, "fairly weak" means that the maximum distance at which a neutron star-neutron star merger would be detectable was 600 kpc during the February/March run and 1 Mpc during the April run.)

LIGO and Virgo ended O3 on March 27, so they and KAGRA were only operating simultaneously during the first part of KAGRA's observations. By my count, of the O3 candidates released ([Abbott et al. 2021](https://arxiv.org/abs/2111.03606)), only four were detected on days when KAGRA was up and running. All were black hole-black hole coalescences with luminosity distances likely over 1 Gpc, nothing particularly easy for KAGRA to find - so again, not surprising that it didn't detect any of them.


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