Open Public Alerts

All the GW events detected so far, are so-called ‘compact binary coalescences‘, i.e. mergers of stellar-mass black holes and/or neutron stars. During the first and second observing runs  the alerts for possible signals were circulated only among partners who had signed agreements with the LIGO/Virgo collaboration.  

Starting from the third scientific run, the alert information became publicly available with a low latency. The Gravitational Wave Open Center (GWOSC) website allows downloading these data and provides as well various software tools to learn how to access and use these data. Dozens of teams outside the LVK collaboration have already used these datasets for applications ranging from fundamental science to education.  The data of the single runs are released and become fully available after about 18 months from the detection, needed for running the basic analyses by the LVK collaboration.

In addition, the Gamma-ray Coordinates Network (GCN)  system is used by the LVK collaboration to distribute early notices, within minutes after a gravitational wave candidate is detected: they are the open public alerts. In order to send out a GCN notice, the candidate should have passed automated data quality checks; however by construction these checks are trade-offs between accuracy and rapidity. As a result, some of these alerts are retracted later, if more detailed analyses find them to have a low probability of being true gravitational wave signals.
For the continuous wave signal and continuous stochastic background the detection process is totally different, as the analysis of long data pieces, for example of the full run, is needed.

Finally, people interested in contributing to the analysis of gravitational-wave data are welcome to join our citizen-science projects like Gwitch hunters