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.
- GRB 240713A: SVOM/GRM observation
- GRB 240713A: 2.2m CAHA optical limit
- GRB240713A: Swift/UVOT Upper LImits
- GRB 240713A: Swift-XRT observations
- GRB 240713A: LAST optical upper limit
- GRB 240713A: optical upper limits from the INAF Asiago Observatory
- GRB 240713A: Tiled Swift observations
- GRB 240713A: J-band upper limit from WINTER
- GRB 240713A: NOT optical upper limits on three EP/FXT candidates
- GRB 240713A: JinShan optical upper limits
- GRB 240713A: OHP/T120 optical upper limit
- GRB240713A: X-ray follow-up observation with EP-FXT