LIGO/Virgo/KAGRA S250119cv
GCN Circular 38986
Subject
LIGO/Virgo/KAGRA S250119cv: Identification of a GW compact binary merger candidate
Date
2025-01-19T19:28:51Z (5 months ago)
From
Julio Martins at National Institute for Space Research <julio.martins@ligo.org>
Via
Web form
The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:
We identified the compact binary merger candidate S250119cv during real-time processing of data from LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) at 2025-01-19 19:02:38.316 UTC (GPS time: 1421348576.316). The candidate was found by the CWB [1], CWB BBH [2], GstLAL [3], MBTA [4], PyCBC Live [5], and SPIIR [6] analysis pipelines.
S250119cv is an event of interest because its false alarm rate, as estimated by the online analysis, is 4e-20 Hz, or about one in 1e12 years. The event's properties can be found at this URL:
https://gracedb.ligo.org/superevents/S250119cv
The classification of the GW signal, in order of descending probability, is BBH (>99%), BNS (<1%), NSBH (<1%), or Terrestrial (<1%).
Assuming the candidate is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [7] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [7] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassGap) is 1%.
Two sky maps are available at this time and can be retrieved from the GraceDB event page:
* bayestar.multiorder.fits,0, an initial localization generated by BAYESTAR [8], distributed via GCN notice about 27 seconds after the candidate event time.
* bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [8], distributed via GCN notice about 5 minutes after the candidate event time.
The preferred sky map at this time is bayestar.multiorder.fits,1. For the bayestar.multiorder.fits,1 sky map, the 90% credible region is well fit by an ellipse with an area of 18 deg2 described by the following DS9 region (right ascension, declination, semi-major axis, semi-minor axis, position angle of the semi-minor axis):
icrs; ellipse(00h55m, +27d29m, 2.56d, 2.20d, 69.78d)
Marginalized over the whole sky, the a posteriori luminosity distance estimate is 478 +/- 126 Mpc (a posteriori mean +/- standard deviation).
For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/.
[1] Klimenko et al. PRD 93, 042004 (2016) doi:10.1103/PhysRevD.93.042004
[2] T. Mishra et al. PRD 105, 083018 (2022) doi:10.1103/PhysRevD.105.083018
[3] Tsukada et al. PRD 108, 043004 (2023) doi:10.1103/PhysRevD.108.043004 and Ewing et al. (2023) arXiv:2305.05625
[4] Aubin et al. CQG 38, 095004 (2021) doi:10.1088/1361-6382/abe913
[5] Dal Canton et al. ApJ 923, 254 (2021) doi:10.3847/1538-4357/ac2f9a
[6] Chu et al. PRD 105, 024023 (2022) doi:10.1103/PhysRevD.105.024023
[7] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe
[8] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013
GCN Circular 38989
Subject
LIGO/Virgo/KAGRA S250119cv: NED Galaxies in the Localization Volume
Date
2025-01-19T20:44:54Z (5 months ago)
From
David Cook at Caltech/IPAC-NED <dcook@ipac.caltech.edu>
Via
Web form
David O. Cook (Caltech/IPAC), Rick Ebert (Caltech/IPAC), George Helou (Caltech/IPAC), Joseph M. Mazzarella (Caltech/IPAC), Marion Schmitz (Caltech/IPAC), and Leo Singer (NASA/GSFC)
On behalf of the NASA/IPAC Extragalactic Database (NED) Team.
We spatially cross-matched the LVK S250119cv-3-Initial sky localization with the NED Local Volume Sample (NED-LVS; Cook et al. 2023), which is a subset of NED with a redshift or redshift-independent distance less than 1000 Mpc. We find 608 galaxies within the 90% containment volume, and we list here the top 20 galaxies sorted by the joint probability of the 3D localization and the WISE W1 luminosity (an observable proxy for stellar mass). For the full or top 20 list of galaxies in the 90% volume go either to the NED Gravitational Wave Followup service at https://ned.ipac.caltech.edu/uri/NED::GWF/ or click on the following links:
Full List Download: https://ned.ipac.caltech.edu/uri/NED::GWFglist/fits/S250119cv/3
Top 20 List Download: https://ned.ipac.caltech.edu/uri/NED::GWFglist/fits/S250119cv/3/20
The NED-GWF service provides downloadable galaxy lists and visualizations for candidate host galaxies. For each GW alert, these products are automatically generated and made available within minutes to expedite efficient electromagnetic follow-up observations. The NED top 20 list is sorted by the joint probability of the 3D localization and the WISE W1 luminosity, but users can sort on additional pre-computed prioritization metrics (star formation rate, P_3D * P_SFR; and specific star formation rate, P_3D * P_sSFR; etc.) which are available via downloading the entire galaxy list inside the event's probability volume.
| objname| ra| dec|objtype| DistMpc|DistMpc_unc| m_NUV| m_NUV_unc| m_Ks| m_Ks_unc| m_W1| m_W1_unc| P_3D|P_3D_LumW1|
|-------------------------|--------------|--------------|-------|-----------|-----------|------------|------------|------------|------------|------------|------------|--------|----------|
|WISEA J010052.08+272244.7| 15.21700| 27.37903| G| 412.82| null| null| null| 13.063| 0.160| 9.482| 0.006|2.68e-06| 1.23e-07|
|WISEA J005734.00+265543.4| 14.39158| 26.92878| G| 310.80| null| null| null| 13.442| 0.147| 11.227| 0.007|6.10e-06| 3.18e-08|
|WISEA J004900.74+271437.7| 12.25312| 27.24382| IrS| 486.42| null| null| null| 13.943| 0.140| 11.573| 0.007|2.46e-06| 2.28e-08|
|WISEA J005638.99+285344.8| 14.16246| 28.89581| G| 358.17| null| 20.378| 0.203| 13.419| 0.074| 10.380| 0.006|1.26e-06| 1.90e-08|
|WISEA J005359.99+271503.0| 13.50000| 27.25086| G| 411.22| 0.10| null| null| 13.288| 0.141| 13.011| 0.017|9.95e-06| 1.76e-08|
|WISEA J005416.61+280547.4| 13.56917| 28.09650| G| 493.98| null| null| null| 13.645| 0.163| 13.208| 0.024|7.38e-06| 1.56e-08|
|WISEA J005121.10+272804.5| 12.83800| 27.46778| G| 422.60| null| 21.151| 0.304| 12.957| 0.115| 12.853| 0.014|6.96e-06| 1.50e-08|
| UGC 00535| 13.13108| 26.13222| G| 220.59| 0.09| null| null| 11.661| 0.089| 10.301| 0.006|2.34e-06| 1.44e-08|
|WISEA J005455.41+284308.6| 13.73092| 28.71911| G| 492.28| 0.15| null| null| 13.138| 0.150| 12.691| 0.013|4.18e-06| 1.42e-08|
|WISEA J005611.18+272126.2| 14.04667| 27.35733| G| 420.81| null| null| null| 13.468| 0.140| 13.351| 0.024|1.03e-05| 1.40e-08|
|WISEA J005522.22+273458.8| 13.84267| 27.58306| G| 546.38| 0.09| 20.390| 0.291| 13.821| 0.188| 13.423| 0.017|6.54e-06| 1.39e-08|
|WISEA J005908.17+265707.9| 14.78412| 26.95225| G| 309.35| null| null| null| 13.456| 0.163| 11.695| 0.007|3.88e-06| 1.31e-08|
|WISEA J005439.87+281009.8| 13.66575| 28.16906| G| 448.78| null| 20.604| 0.225| 13.617| 0.169| 13.248| 0.018|7.52e-06| 1.27e-08|
|WISEA J005530.30+274200.2| 13.87629| 27.70008| IrS| 545.80| 0.03| null| null| 13.778| 0.164| 13.553| 0.025|6.59e-06| 1.24e-08|
|WISEA J004703.00+270038.7| 11.76246| 27.01083| G| 325.40| null| 19.853| 0.133| 12.937| 0.135| 11.032| 0.006|1.82e-06| 1.24e-08|
|WISEA J005515.68+275512.4| 13.81533| 27.92003| G| 393.72| 0.08| null| null| 13.807| 0.194| 13.123| 0.013|8.21e-06| 1.20e-08|
| NGC 0326| 14.59458| 26.86528| GPair| 211.54| 0.92| null| null| null| null| 10.233| 0.007|1.96e-06| 1.19e-08|
|WISEA J005642.85+265022.8| 14.17850| 26.83967| G| 325.92| null| null| null| 12.596| 0.108| 12.654| 0.010|7.31e-06| 1.13e-08|
|WISEA J005714.88+274253.8| 14.31200| 27.71489| G| 404.88| 0.04| null| null| 13.679| 0.093| 13.234| 0.025|7.94e-06| 1.11e-08|
|WISEA J005413.03+271750.3| 13.55433| 27.29731| G| 444.44| null| null| null| 13.625| 0.156| 13.660| 0.025|9.75e-06| 1.11e-08|
Table 1: Top 20 galaxies in NED-LVS that fall in the 90% probability volume for S250119cv sorted by the joint probability of 3D position and WISE W1 luminosity (P_3D * P_LumW1). Galaxy is the NED preferred name. RA and Dec are the Equatorial coordinates in degrees (J2000). Objtype is the object type of the galaxy candidate. Distance is the distance to the galaxy in Mpc. m_NUV and mErr_NUV are the apparent magnitude and error from GALEX. m_Ks and mErr_Ks are the apparent magnitude and error from 2MASS. m_W1 and mErr_W1 are the apparent magnitude and error from AllWISE. P_3D is the probability that the galaxy is in the volume given the distance of GW event. P_3D_LumW1 is the joint probability within the volume weighted by the WISE1 luminosity of the galaxy (P_3D * P_LumW1).
GCN Circular 38991
Subject
LIGO/Virgo/KAGRA S250119cv: Updated Sky localization and EM Bright Classification
Date
2025-01-20T00:39:00Z (5 months ago)
From
Soichiro Morisaki at U. of Tokyo <soichiro.morisaki@ligo.org>
Via
Web form
The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:
We have conducted further analysis of the LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) data around the time of the compact binary merger (CBC) candidate S250119cv (GCN Circular 38986). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:
https://gracedb.ligo.org/superevents/S250119cv
Based on posterior support from parameter estimation [1], under the assumption that the candidate S250119cv is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassGap) is <1%.
For the Bilby.multiorder.fits,0 sky map, the 90% credible region is well fit by an ellipse with an area of 9 deg2 described by the following DS9 region (right ascension, declination, semi-major axis, semi-minor axis, position angle of the semi-minor axis):
icrs; ellipse(00h56m, +26d48m, 1.84d, 1.56d, 72.16d)
Marginalized over the whole sky, the a posteriori luminosity distance estimate is 472 +/- 112 Mpc (a posteriori mean +/- standard deviation).
For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/.
[1] Ashton et al. ApJS 241, 27 (2019) doi:10.3847/1538-4365/ab06fc and Morisaki et al. (2023) arXiv:2307.13380
[2] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe
GCN Circular 38992
Subject
LIGO/Virgo/KAGRA S250119cv: Updated NED Galaxies in the Localization Volume
Date
2025-01-20T00:54:50Z (5 months ago)
From
David Cook at Caltech/IPAC-NED <dcook@ipac.caltech.edu>
Via
Web form
David O. Cook (Caltech/IPAC), Rick Ebert (Caltech/IPAC), George Helou (Caltech/IPAC), Joseph M. Mazzarella (Caltech/IPAC), Marion Schmitz (Caltech/IPAC), and Leo Singer (NASA/GSFC)
On behalf of the NASA/IPAC Extragalactic Database (NED) Team.
We spatially cross-matched the LVK S250119cv-4-Update sky localization with the NED Local Volume Sample (NED-LVS; Cook et al. 2023), which is a subset of NED with a redshift or redshift-independent distance less than 1000 Mpc. We find 264 galaxies within the 90% containment volume, and we list here the top 20 galaxies sorted by the joint probability of the 3D localization and the WISE W1 luminosity (an observable proxy for stellar mass). For the full or top 20 list of galaxies in the 90% volume go either to the NED Gravitational Wave Followup service at https://ned.ipac.caltech.edu/uri/NED::GWF/ or click on the following links:
Full List Download: https://ned.ipac.caltech.edu/uri/NED::GWFglist/fits/S250119cv/4
Top 20 List Download: https://ned.ipac.caltech.edu/uri/NED::GWFglist/fits/S250119cv/4/20
The NED-GWF service provides downloadable galaxy lists and visualizations for candidate host galaxies. For each GW alert, these products are automatically generated and made available within minutes to expedite efficient electromagnetic follow-up observations. The NED top 20 list is sorted by the joint probability of the 3D localization and the WISE W1 luminosity, but users can sort on additional pre-computed prioritization metrics (star formation rate, P_3D * P_SFR; and specific star formation rate, P_3D * P_sSFR; etc.) which are available via downloading the entire galaxy list inside the event's probability volume.
| objname| ra| dec|objtype| DistMpc|DistMpc_unc| m_NUV| m_NUV_unc| m_Ks| m_Ks_unc| m_W1| m_W1_unc| P_3D|P_3D_LumW1|
|-------------------------|--------------|--------------|-------|-----------|-----------|------------|------------|------------|------------|------------|------------|--------|----------|
|WISEA J010052.08+272244.7| 15.21700| 27.37903| G| 412.82| null| null| null| 13.063| 0.160| 9.482| 0.006|3.08e-06| 3.18e-07|
|WISEA J005607.30+262638.7| 14.03046| 26.44408| G| 494.35| 0.08| null| null| 13.516| 0.147| 13.060| 0.028|1.14e-05| 6.25e-08|
|WISEA J005556.23+263010.8| 13.98417| 26.50308| G| 489.28| 0.48| null| null| 13.560| 0.174| 13.311| 0.020|1.27e-05| 5.40e-08|
|WISEA J005948.86+263351.3| 14.95367| 26.56428| G| 407.84| null| 20.155| 0.094| 13.132| 0.139| 12.600| 0.011|8.56e-06| 4.88e-08|
| UGC 00535| 13.13108| 26.13222| G| 220.59| 0.09| null| null| 11.661| 0.089| 10.301| 0.006|3.48e-06| 4.81e-08|
|WISEA J005802.01+274134.0| 14.50842| 27.69286| G| 528.34| null| 21.078| 0.347| 13.493| 0.155| 13.513| 0.018|1.04e-05| 4.28e-08|
|WISEA J005607.67+254804.7| 14.03167| 25.80111| G| 471.60| null| 18.108| 0.052| 13.402| 0.132| 12.514| 0.023|5.09e-06| 4.19e-08|
|WISEA J005801.84+270201.6| 14.50800| 27.03431| G| 484.58| null| 20.807| 0.258| 13.712| 0.172| 14.040| 0.048|1.93e-05| 4.13e-08|
|WISEA J005219.16+261631.6| 13.07933| 26.27567| G| 282.70| null| null| null| 12.640| 0.082| 11.628| 0.007|5.94e-06| 3.97e-08|
|WISEA J005612.58+255012.0| 14.05271| 25.83672| G| 584.23| null| null| null| 12.708| 0.120| 12.073| 0.010|2.07e-06| 3.93e-08|
|WISEA J005622.27+262812.4| 14.09271| 26.46994| G| 358.94| 0.73| 19.715| 0.146| 13.693| 0.180| 12.830| 0.010|1.07e-05| 3.83e-08|
|WISEA J005734.00+265543.4| 14.39158| 26.92878| G| 310.80| null| null| null| 13.442| 0.147| 11.227| 0.007|3.25e-06| 3.81e-08|
|WISEA J005737.99+263814.8| 14.40834| 26.63756| G| 636.80| 0.29| null| null| 13.166| 0.116| 12.752| 0.017|3.08e-06| 3.71e-08|
|WISEA J005522.22+273458.8| 13.84267| 27.58306| G| 546.38| 0.09| 20.390| 0.291| 13.821| 0.188| 13.423| 0.017|7.75e-06| 3.71e-08|
|WISEA J005359.99+271503.0| 13.50000| 27.25086| G| 411.22| 0.10| null| null| 13.288| 0.141| 13.011| 0.017|8.86e-06| 3.51e-08|
|WISEA J005611.18+272126.2| 14.04667| 27.35733| G| 420.81| null| null| null| 13.468| 0.140| 13.351| 0.024|1.08e-05| 3.29e-08|
|WISEA J005530.30+274200.2| 13.87629| 27.70008| IrS| 545.80| 0.03| null| null| 13.778| 0.164| 13.553| 0.025|7.59e-06| 3.22e-08|
|WISEA J005201.48+261645.2| 13.00621| 26.27922| IrS| 390.49| null| null| null| 12.838| 0.104| 12.605| 0.012|6.04e-06| 3.13e-08|
|WISEA J005817.42+254530.5| 14.57217| 25.75844| G| 369.84| 0.10| null| null| 13.157| 0.130| 12.920| 0.012|7.85e-06| 2.74e-08|
|WISEA J005413.03+271750.3| 13.55433| 27.29731| G| 444.44| null| null| null| 13.625| 0.156| 13.660| 0.025|1.03e-05| 2.63e-08|
Table 1: Top 20 galaxies in NED-LVS that fall in the 90% probability volume for S250119cv sorted by the joint probability of 3D position and WISE W1 luminosity (P_3D * P_LumW1). Galaxy is the NED preferred name. RA and Dec are the Equatorial coordinates in degrees (J2000). Objtype is the object type of the galaxy candidate. Distance is the distance to the galaxy in Mpc. m_NUV and mErr_NUV are the apparent magnitude and error from GALEX. m_Ks and mErr_Ks are the apparent magnitude and error from 2MASS. m_W1 and mErr_W1 are the apparent magnitude and error from AllWISE. P_3D is the probability that the galaxy is in the volume given the distance of GW event. P_3D_LumW1 is the joint probability within the volume weighted by the WISE1 luminosity of the galaxy (P_3D * P_LumW1).
GCN Circular 38996
Subject
LIGO/Virgo/KAGRA S250119cv: GLADEnet Completeness: Potential Host Galaxies in the 90% Credible Volume
Date
2025-01-20T10:28:32Z (5 months ago)
From
Maria Lisa Brozzetti at Università degli Studi di Perugia <marialisa.brozzetti@ligo.org>
Via
Web form
M. L. Brozzetti (UniPG/INFN), G. Dálya (L2IT/EotvosU), G. Greco (INFN), M. Bawaj (UniPG/INFN), T. Matcovich (UniPG/INFN), S. Cutini (INFN) , R. De Pietri (UniPR/INFN), Marica Branchesi (GSSI)
On behalf of the GLADEnet Team.
We analyzed the completeness of the GLADE+ [1] catalog within the 90% credible localization volume of the S250119cv event from the 4-Update alert from the GCN Circular 38986.
The completeness value is 5.0e-1 in the B-band using the last released skymap : Bilby.multiorder.fits,0, which means that the catalogue contains 50% of the total light in the B-band expected from galaxies in the localization volume.
A total of 1469 galaxies are identified within the 90% gravitational volume. The complete list of galaxies can be downloaded from the GLADEnet webpage [2] : https://virgo.pg.infn.it/gladenet/catalogs/
GLADEnet allows for the interactive visualization of the 90% localization area and its intersection with regions of high extinction as defined in GLADE+. Furthermore, the first 1000 galaxies can be explored interactively, enabling users to filter galaxies based on their 3D probability density or their absolute B magnitude. The ligo.skymap cross-match method [3,4] is used to obtain the list of galaxies.
References:
[1]GLADE+: An Extended Galaxy Catalogue for Multimessenger Searches with Advanced Gravitational-wave Detectors
G. Dálya et al. MNRAS, 514,1, pp.1403-1411, 2022
[2] GLADEnet: A progressive web app for multi-messenger cosmology and electromagnetic follow-ups of gravitational-wave sources M. L. Brozzetti, G. Dálya, G. Greco, M. Bawaj, T. Matcovich, M. Branchesi, T. Boch, M. Baumann, S. Cutini, R. De Pietri et al. (4 more) A&A, 684, A44 (2024)
[3] Singer, L. P., Chen, H.-Y., Holz, D. E., et al. 2016, Astropys. J. Lett., 829, L15. doi:10.3847/2041-8205/829/1/L15
[4] Singer, L. P., Chen, H.-Y., Holz, D. E., et al. 2016, Astropys. J. Supp., 226, 10. doi:10.3847/0067-0049/226/1/10