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"13 results found.
- GRB 210726A: VLA radio afterglow detection
- GRB 210726A: Chandra detection of the X-ray afterglow
- GRB 210726A: OSIRIS/GTC observations
- GRB 210726A: Deep CAHA 2.2m limit
- GRB 210726A: 6 GHz VLA radio upper limit
- Fermi GBM Sub-Threshold Detection of GRB 210726A
- GRB 210726A: Swift-XRT refined Analysis
- GRB 210726A: Swift-BAT refined analysis
- GRB 210726A: Likely a short burst
- GRB 210726A: RATIR Optical Upper Limits and Candidate Host Galaxy
- GRB 210726A: CAHA 2.2m telescope optical limit
- GRB 210726A: Enhanced Swift-XRT position
- GRB 210726A: Swift detection of a burst