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"16 results found.
- GRB 200122A: Optical upper limit: correction to the GCN circ. 26870
- GRB 200122A: AstroSat CZTI detection
- GRB 200122A: Optical upper limit
- GRB 200122A: Mondy optical upper limit
- Konus-Wind observation of GRB 200122A
- GRB 200122A: MITSuME Akeno optical upper limits
- GRB 200122A: RATIR Optical Observations
- GRB 200122A: Swift-BAT refined analysis
- GRB 200122A: Xinglong-2.16m optical upper limit
- GRB 200122A: Swift/UVOT Upper Limits
- GRB 200122A: FRAM-ORM optical limit
- GRB 200122A: GOTO non-detection of optical afterglow
- GRB 200122A: Swift-XRT refined Analysis
- GRB 200122A: Enhanced Swift-XRT position
- Swift GRB 200122A: Global MASTER-Net observations report
- GRB 200122A: Swift detection of a burst