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"9 results found.
- GRB 251106A: Swift/UVOT Upper Limits
- GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
- GRB 251106A: Swift-XRT afterglow detection
- GRB 251106A: Kilonova-Catcher optical upper limit
- Fermi GBM Sub-Threshold Detection of GRB 251106A
- GRB 251106A: Swift/BAT arcminute localization of a burst
- GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
- GRB 251106A: MASTER optical observations
- GRB 251106A: SVOM detection of a burst