LIGO/Virgo/KAGRA S250114ax
GCN Circular 38932
Subject
LIGO/Virgo/KAGRA S250114ax: Identification of a GW compact binary merger candidate
Date
2025-01-14T09:06:32Z (5 months ago)
From
Enzo Tapia at Nikhef <e.tapia@nikhef.nl>
Via
Web form
The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:
We identified the compact binary merger candidate S250114ax during real-time processing of data from LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) at 2025-01-14 08:22:03.223 UTC (GPS time: 1420878141.223). The candidate was found by the CWB [1], cWB BBH [2], GstLAL [3], MBTA [4], MLy [5], PyCBC Live [6], and SPIIR [7] analysis pipelines.
S250114ax is an event of interest because its false alarm rate, as estimated by the online analysis, is 4.1e-27 Hz, or about one in 1e19 years. The event's properties can be found at this URL:
https://gracedb.ligo.org/superevents/S250114ax
After parameter estimation by RapidPE-RIFT [8], the classification of the GW signal, in order of descending probability, is BBH (>99%), NSBH (<1%), BNS (<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%. [9] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [8] 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 [10], distributed via GCN notice about 28 seconds after the candidate event time.
* bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [10], distributed via GCN notice about 5 minutes after the candidate event time.
The preferred sky map at t
his time is bayestar.multiorder.fits,1. For the bayestar.multiorder.fits,1 sky map, the 90% credible region is 37 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 473 +/- 99 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] Skliris et al. (2020) arXiv:2009.14611
[6] Dal Canton et al. ApJ 923, 254 (2021) doi:10.3847/1538-4357/ac2f9a
[7] Chu et al. PRD 105, 024023 (2022) doi:10.1103/PhysRevD.105.024023
[8] Rose et al. (2022) arXiv:2201.05263 and Pankow et al. PRD 92, 023002 (2015) doi:10.1103/PhysRevD.92.023002
[9] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe
[10] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013
GCN Circular 38939
Subject
LIGO/Virgo/KAGRA S250114ax: NED Galaxies in the Localization Volume
Date
2025-01-14T14:45:29Z (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 S250114ax-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 2284 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/S250114ax/3
Top 20 List Download: https://ned.ipac.caltech.edu/uri/NED::GWFglist/fits/S250114ax/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 J093220.56+251556.2| 143.08562| 25.26563| G| 292.07| 0.05| null| null| null| null| 8.990| 0.006|8.06e-07| 8.74e-09|
|WISEA J102022.07+355930.8| 155.09194| 35.99190| G| 483.78| 0.12| null| null| 13.320| 0.129| 11.845| 0.007|3.12e-06| 6.68e-09|
|WISEA J100500.42+324505.5| 151.25175| 32.75138| G| 423.57| 0.09| null| null| 13.634| 0.132| 10.078| 0.006|7.72e-07| 6.45e-09|
|WISEA J090550.01+152107.3| 136.45835| 15.35192| G| 511.52| 0.08| null| null| 14.307| 0.263| 9.604| 0.006|2.25e-07| 4.25e-09|
|WISEA J093527.08+261709.6| 143.86289| 26.28603| QSO| 574.23| 0.10| 17.503| 0.029| 12.834| 0.101| 11.630| 0.007|1.11e-06| 4.10e-09|
|WISEA J101629.63+352013.4| 154.12351| 35.33699| G| 473.98| 0.06| null| null| 13.767| 0.099| 12.577| 0.013|3.31e-06| 3.47e-09|
|WISEA J100502.47+332945.3| 151.26023| 33.49586| G| 427.12| 0.08| null| null| 12.666| 0.089| 12.471| 0.010|3.69e-06| 3.46e-09|
|WISEA J101541.71+351111.6| 153.92387| 35.18652| G| 471.79| 0.11| null| null| 12.981| 0.125| 12.653| 0.015|3.33e-06| 3.22e-09|
|WISEA J101130.53+341204.0| 152.87724| 34.20114| G| 457.03| 0.21| null| null| 12.380| 0.104| 12.339| 0.010|2.55e-06| 3.10e-09|
|WISEA J094400.34+285226.8| 146.00147| 28.87415| G| 481.46| 0.21| null| null| 12.867| 0.181| 12.587| 0.012|2.67e-06| 2.86e-09|
|WISEA J100754.06+340153.1| 151.97529| 34.03149| G| 591.45| 0.08| 20.521| 0.228| 12.676| 0.100| 11.987| 0.007|1.01e-06| 2.83e-09|
|WISEA J095318.32+310410.9| 148.32637| 31.06973| G| 371.11| 0.03| 18.643| 0.046| 12.727| 0.098| 12.440| 0.012|3.81e-06| 2.78e-09|
|WISEA J101816.94+354434.1| 154.57056| 35.74274| G| 413.32| 0.11| null| null| 12.650| 0.092| 12.412| 0.011|2.99e-06| 2.78e-09|
|WISEA J094414.06+291215.5| 146.05861| 29.20431| G| 515.30| 0.07| null| null| 12.525| 0.113| 12.242| 0.010|1.51e-06| 2.55e-09|
|WISEA J102925.12+373747.7| 157.35468| 37.63001| G| 478.02| 0.14| null| null| 12.296| 0.039| 11.825| 0.007|1.19e-06| 2.53e-09|
|WISEA J093428.88+272228.7| 143.62045| 27.37482| G| 429.38| null| null| null| 13.506| 0.140| 9.935| 0.006|2.53e-07| 2.48e-09|
|WISEA J100754.29+340159.5| 151.97629| 34.03308| G| 600.01| 0.14| null| null| 13.311| 0.029| 12.035| 0.010|8.85e-07| 2.45e-09|
|WISEA J101631.11+352122.8| 154.12966| 35.35631| G| 481.62| 0.09| null| null| 13.255| 0.109| 12.996| 0.012|3.21e-06| 2.36e-09|
|WISEA J094637.73+294313.0| 146.65722| 29.72030| G| 519.41| 0.23| 21.678| 0.342| 12.783| 0.132| 12.444| 0.009|1.65e-06| 2.35e-09|
|WISEA J093805.80+270456.9| 144.52418| 27.08243| G| 414.27| 0.09| 21.530| 0.257| 13.756| 0.071| 12.595| 0.024|2.84e-06| 2.24e-09|
Table 1: Top 20 galaxies in NED-LVS that fall in the 90% probability volume for S250114ax 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 38951
Subject
LIGO/Virgo/KAGRA S250114ax: GLADEnet Completeness: Potential Host Galaxies in the 90% Credible Volume
Date
2025-01-15T11:58:18Z (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 (UniPG/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 S250114ax event from the 3-Initial alert from the GCN Circular 38932.
The completeness value is 4.4e-1 in the B-band using the last released skymap : bayestar.multiorder.fits,1, which means that the catalogue contains 44% of the total light in the B-band expected from galaxies in the localization volume.
A total of 5511 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
GCN Circular 38955
Subject
LIGO/Virgo/KAGRA S250114ax: Updated Sky localization
Date
2025-01-15T17:12:57Z (5 months ago)
From
Patricia Schmidt at University of Birmingham <patricia.schmidt@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) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S250114ax (GCN Circular ***CITE ORIGINAL GCN ID, e.g. 38932***). 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/S250114ax
For the Bilby.multiorder.fits,0 sky map, the 90% credible region is 145 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 385 +/- 49 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
GCN Circular 38957
Subject
LIGO/Virgo/KAGRA S250114ax: Updated NED Galaxies in the Localization Volume
Date
2025-01-15T17:29:30Z (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 S250114ax-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 3851 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/S250114ax/4
Top 20 List Download: https://ned.ipac.caltech.edu/uri/NED::GWFglist/fits/S250114ax/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 J100500.42+324505.5| 151.25175| 32.75138| G| 423.57| 0.09| null| null| 13.634| 0.132| 10.078| 0.006|1.26e-06| 7.67e-09|
|WISEA J115623.09+445139.1| 179.09635| 44.86105| G| 314.71| 0.06| 21.467| 0.316| 13.724| 99.000| 9.624| 0.006|1.21e-06| 6.17e-09|
|WISEA J105708.99+403512.2| 164.28746| 40.58676| G| 411.64| null| null| null| 13.533| 0.147| 11.565| 0.008|3.13e-06| 4.59e-09|
|WISEA J110915.34+413340.7| 167.31395| 41.56143| G| 349.06| 0.07| 21.404| 0.319| 11.423| 0.091| 11.701| 0.008|2.65e-06| 2.46e-09|
|WISEA J111211.85+421834.7| 168.04936| 42.30966| G| 367.29| 0.08| 20.038| 0.166| 12.893| 0.131| 12.098| 0.008|3.41e-06| 2.43e-09|
|WISEA J092056.01+194727.2| 140.23333| 19.79083| G| 401.36| 0.03| null| null| 14.106| 0.203| 10.088| 0.006|4.25e-07| 2.32e-09|
|WISEA J120613.48+452001.3| 181.55612| 45.33371| G| 349.47| 0.05| 18.190| 0.055| 11.620| 0.044| 11.375| 0.006|1.80e-06| 2.27e-09|
|WISEA J093428.88+272228.7| 143.62045| 27.37482| G| 429.38| null| null| null| 13.506| 0.140| 9.935| 0.006|2.92e-07| 2.09e-09|
|WISEA J110931.66+413353.3| 167.38212| 41.56486| G| 359.90| 0.37| null| null| 13.527| 0.150| 12.204| 0.008|3.12e-06| 1.94e-09|
|WISEA J103714.13+374030.7| 159.30885| 37.67520| G| 389.27| 0.16| 21.790| 0.148| 12.035| 0.079| 12.054| 0.008|2.30e-06| 1.92e-09|
|WISEA J104816.70+393833.3| 162.06963| 39.64257| G| 367.73| 0.12| 21.671| 0.151| 12.483| 0.073| 12.343| 0.008|3.36e-06| 1.92e-09|
|WISEA J111237.50+423546.8| 168.15621| 42.59659| G| 368.55| 0.14| null| null| 11.885| 0.093| 11.940| 0.007|2.30e-06| 1.92e-09|
|WISEA J110930.98+413350.1| 167.37908| 41.56396| G| 358.54| 0.08| null| null| 13.572| 0.048| 12.227| 0.010|3.12e-06| 1.89e-09|
|WISEA J111455.39+420838.9| 168.73079| 42.14411| G| 370.21| 0.17| 21.340| 0.169| 12.763| 0.110| 12.564| 0.012|3.97e-06| 1.88e-09|
|WISEA J122323.53+463630.7| 185.84804| 46.60852| G| 357.96| 0.07| 18.214| 0.016| 12.290| 0.104| 11.651| 0.007|1.83e-06| 1.87e-09|
|WISEA J105612.55+402802.0| 164.05226| 40.46726| G| 414.71| null| 19.671| 0.125| 12.877| 0.089| 12.543| 0.015|3.05e-06| 1.84e-09|
|WISEA J111620.92+420056.6| 169.08707| 42.01561| G| 375.55| 0.08| null| null| 13.334| 0.140| 12.046| 0.007|2.33e-06| 1.82e-09|
|WISEA J111621.84+420102.9| 169.09088| 42.01737| G| 372.99| 0.02| 19.063| 0.024| 12.928| 0.123| 12.042| 0.008|2.31e-06| 1.79e-09|
|WISEA J103836.82+382454.0| 159.65336| 38.41500| G| 385.86| 0.18| null| null| 12.737| 0.093| 12.413| 0.012|3.03e-06| 1.79e-09|
|WISEA J103517.11+374300.4| 158.82118| 37.71685| G| 395.44| 0.09| 21.068| 0.087| 12.973| 0.095| 12.436| 0.010|2.91e-06| 1.77e-09|
Table 1: Top 20 galaxies in NED-LVS that fall in the 90% probability volume for S250114ax 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).