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.
- GRB 240619A: Host galaxy redshift from VLT/X-shooter
- Konus-Wind detection of GRB 240619A
- GRB 240619A: detection of a radio counterpart with AMI-LA
- GRB 240619A: J-band detection with WINTER (duplicate submission of GCN 36739)
- GRB 240619A: J-band detection with WINTER
- GRB 240619A: GRBAlpha detection
- GRB 240619A: Swift-XRT probable afterglow detection
- GRB 240619A: Swift ToO observations
- GRB 240619A: CALET Gamma-Ray Burst Monitor detection
- GRB 240619A: Fermi GBM Observation
- GRB 240619A: GOTO candidate optical afterglow
- Fermi GRB 240619A: Global MASTER-Net observations report
- GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
- GRB 240619A: Fermi GBM Final Real-time Localization