TITLE: GCN CIRCULAR NUMBER: 34142 SUBJECT: LVK S230619bd/GBM-230619: Upper limits from a two-week IceCube neutrino search DATE: 23/07/04 16:14:26 GMT FROM: Jessie Thwaites at IceCube/U Wisc-Madison The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed an additional search for track-like muon neutrino events consistent with the sky localization of the joint skymap for low significance gravitational-wave candidate S230619bd and GBM-230619 (https://gcn.nasa.gov/circulars/34054) in a time range of -0.1 day, +14 days from the GW alert event time (2023-06-19 17:01:06.4 UTC to 2023-07-03 19:25:06.4 UTC). During this time period IceCube was collecting good quality data. This is a maximum likelihood analysis which searches for a generic point-like neutrino source coincident with the given GW skymap [1,2]. In this case, we report a p-value of 0.31, consistent with no significant excess of track events. IceCube's sensitivity assuming an E^-2 spectrum (E^2 dN/dE) to neutrino point sources within the locations spanned by the 90% spatial containment of the joint skymap ranges from 0.037 to 0.061 GeV cm^-2 in this time window. A Bayesian search [1,2] was also performed, using the standard time window of 1000 seconds centered on the alert event time (2023-06-19 19:16:46 UTC to 2023-06-19 19:33:26 UTC), and using the the map for S230619bd circulated in the 2-Preliminary notice. This search uses a Bayesian approach to quantify the joint GW + neutrino event significance, which assumes a binary merger scenario and accounts for known astrophysical priors, such as GW source distance, in the significance estimate [3]. For this search we report a p-value of 0.22, consistent with no significant events coincident with the map. IceCube's sensitivity assuming an E^-2 spectrum (E^2 dN/dE) to neutrino point sources within the locations spanned by the 90% spatial containment of the 2-Preliminary map ranges from 0.0277 to 1.0771 GeV cm^-2 in a 1000 second time window. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu. [1] M. G. Aartsen et al 2020 ApJL 898 L10 [2] Abbasi et al. Astrophys.J. 944 (2023) 1, 80 [3] I. Bartos et al. 2019 Phys. Rev. D 100, 083017