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"11 results found.
- EP 250108A: Upper limits from Fermi-GBM Observations
- EP 250108A: Late-time optical observation by LCO
- EP250108a / AT2025kg: GMG Optical Observations
- GRB 250108A: Swift/XRT afterglow fading
- EP-WXT trigger EP250108a：Xinglong optical follow-up observations
- GRB 250108A: Swift/UVOT Upper Limits
- GRB 250108A: NOT optical upper limit
- GRB 250108A: Swift-XRT afterglow detection
- GRB 250108A:SVOM/VT optical candidate
- GRB 250108A: Swift ToO observations
- GRB 250108A: SVOM detection of a soft long burst