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.
Lucene Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"13 results found.
- GRB 250327A: Swift/UVOT Upper Limits
- GRB 250327A Swift-BAT refined analysis
- GRB 250327A: SVOM/VT upper limits on the XRT position
- GRB 250327A: Swift-XRT refined Analysis
- GRB 250327A: J-band observations with WINTER
- GRB 250327A: SVOM/VT optical candidate
- GRB 250327A: Fermi GBM observation
- Fermi GRB 250327A: Global MASTER-Net observations report
- Swift GRB 250327A: Global MASTER-Net observations report
- GRB 250327A: DDOTI Optical Observations
- GRB 250327A: COLIBRÍ optical upper limit
- GRB 250327A: Swift detection of a burst
- GRB 250327A: Fermi GBM Final Real-time Localization