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"12 results found.
- Konus-Wind detection of GRB 250601A
- GRB 250601A: PRIME H band upper limit.
- GRB 250601A: PRIME J band upper limit.
- GRB 250601A: VLT/FORS2 Optical Observation
- GRB 250601A: Fermi GBM Observation
- GRB 250601A: EP-FXT follow-up observation and afterglow candidates
- GRB 250601A: Swift/XRT candidate afterglow
- GRB 250601A: Swift-XRT observations
- Fermi GRB 250601A: Global MASTER-Net observations report
- GRB 250601A: Swift/BAT-GUANO arcminute localization of a likely short burst
- GRB 250601A: Swift ToO observations
- GRB 250601A: Fermi GBM Final Real-time Localization