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"18 results found.
- GRB 250128B: VLA possible radio detection
- GRB 250128B: SAO RAS Zeiss-1000 and CrAO ZTSh optical upper limits
- GRB 250128B: VLA radio upper limit
- GRB 250128B: Gemini-North optical extended source detection
- GRB 250128B: TNG optical upper limit
- GRB 250128B: VLT/HAWKI near-infrared observations
- GRB 250128B: NOT optical upper limit
- GRB 250128B: VLT/FORS2 optical observations
- GRB 250128B: OHP/T193 optical upper limit
- GRB 250128B: Enhanced Swift-XRT position
- Fermi GRB 250128B: Global MASTER-Net observations report
- GRB 250128B: Swift-XRT refined Analysis
- GRB 250128B: Fermi GBM Observation
- GRB 250128B: GOTO optical upper limit
- Swift GRB 250128B: Global MASTER-Net observations report
- GRB 250128B: LCO optical observations
- GRB 250128B: Swift detection of a short burst
- GRB 250128B: Fermi GBM Final Real-time Localization