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GCN Circular 33891

LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
2023-05-29T20:03:57Z (a year ago)
J. L. Wright at Australian National University <>
The LIGO Scientific Collaboration, the Virgo Collaboration, and the
KAGRA Collaboration report:

We have conducted further analysis of the LIGO Livingston Observatory
(L1) data around the time of the compact binary merger (CBC) candidate
S230529ay (GCN Circular 33889).
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:

Based on posterior support from parameter estimation [1], under the
assumption that the candidate S230529ay is astrophysical in origin,the
probability that the lighter compact object is consistent with a
neutron star mass (HasNS) is 98%. [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 any one of the binary components lie between 3 to 5
solar mass (HasMassgap) is 69%.

For the Bilby.multiorder.fits,0 sky map, the 90% credible region is
25623 deg2. Marginalized over the whole sky, the a posteriori
luminosity distance estimate is 201 +/- 63 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

 [1] Ashton et al. ApJS 241, 27 (2019)
 [2] Chatterjee et al. The Astrophysical Journal 896, 1 (2020)
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