TITLE: GCN CIRCULAR NUMBER: 24411 SUBJECT: LIGO/Virgo S190426c: Update on Source Classification DATE: 19/05/06 16:21:43 GMT FROM: Deep Chatterjee at University of Wisconsin, Milwaukee LIGO/Virgo S190426c: Update on Source Classification The LIGO Scientific Collaboration and Virgo Collaboration report: Based on posterior support from preliminary parameter estimation [1,2], under the assumption that the candidate S190426c is astrophysical in origin, the relative probabilities amongst the signal categories NSBH : MassGap : BNS : BBH are revised to be approximately 12 : 5 : 3 : 0. Under the same assumption of astrophysical origin, we find strong evidence that the lighter compact object has a mass < 3 solar masses (HasNS: >99%) and a 72% probability of having disrupted material outside the final compact object (HasRemnant: 72%). The probability of non-astrophysical origin and the false alarm rate are not being updated at this time; both measures of significance should be expected to change with offline analyses and continued observations. For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo Public Alerts User Guide . [1] Veitch, et al. PRD 91, 042003 (2015) [2] Abbott, et al. PRL 116, 241102 (2016)