GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search
To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"14 results found.
- Updates to IceCube realtime alert system for muon tracks
- Fermi-LAT Gamma-ray Observations of IceCube-241006A
- GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
- GRB 240929A: Liverpool Telescope prompt followup observations
- GRB 240929A: GRBAlpha detection
- Fermi-LAT Gamma-ray Observations of IceCube-240929A
- GRB 240929A: SVOM/GRM observation
- IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
- GRB 240929A : Leavitt Observatory optical upper limit
- GRB 240929A long GRB detected by INTEGRAL
- GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
- Fermi GRB 240929A: Global MASTER-Net observations report
- GRB 240929A: Fermi GBM Final Real-time Localization
- IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event