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"17 results found.
- GRB 250813B: Swift/UVOT Upper Limit
- GRB 250813B: SVOM/ECLAIRs refined analysis
- GRB 250813B: Liverpool Telescope optical upper limits
- GRB 250813B: Calapai Observatory, Massa S. Giorgio (Messina), upper limit
- GRB 250813B: SVOM/GRM observation
- GRB 250813B: Fermi GBM Observation
- GRB 250813B: NOT observations of the optical afterglow
- GRB 250813B: SVOM/VT optical observations
- Subject GRB 250813B: SVOM/MXT refined analysis
- GRB 250813B: VLT X-shooter spectroscopic redshift z = 1.752
- GRB 250813B: EP-FXT counterpart detection
- GRB 250813B: Swift-XRT afterglow detection
- GRB 250813B: SVOM/COLIBRÍ (FM-GFT) optical observations
- GRB 250813B: Ondrejov D50 fast decay
- GRB 250813B: SVOM detection of a bright long burst (Correction for GCN 41352).
- GRB 250813B: Ondrejov D50 optical afterglow detection
- GRB 250813B: SVOM detection of a bright long burst