TITLE: GCN CIRCULAR NUMBER: 26905 SUBJECT: LIGO/Virgo S200128d: Upper limits from IceCube neutrino searches DATE: 20/01/28 02:52:42 GMT FROM: Raamis Hussain at IceCube IceCube Collaboration (http://icecube.wisc.edu/) reports: Searches [1,2] for track-like muon neutrino events detected by IceCube consistent with the sky localization of gravitational-wave candidate S200128d in a time range of 1000 seconds [3] centered on the alert event time (2020-01-28 02:11:51.903 UTC to 2020-01-28 02:28:31.903 UTC) have been performed. During this time period IceCube was collecting good quality data. No significant track-like events are found in spatial coincidence of S200128d calculated from the map circulated in the 1-Preliminary notice. 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 S200128d ranges from 0.029 to 0.966 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] Bartos et al. arXiv:1810.11467 (2018) and Countryman et al.arXiv:1901.05486 (2019) [2] PoS(ICRC2019)918 and Braun et al., Astroparticle Physics 29, 299 (2008) [3] Baret et al., Astroparticle Physics 35, 1 (2011)