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 201020A: 1.3m DFOT, optical upper limits
- GRB 201020A: GROWTH-India Telescope late-time optical upper limit
- Konus-Wind detection of GRB 201020A
- GRB 201020A: Swift/UVOT Observations
- GRB 201020A: VIRT optical observations
- GRB 201020A: Redshift from GTC/OSIRIS
- GRB 201020A: DOAO optical afterglow observations
- GRB 201020A: GROWTH-India Telescope optical observations
- GRB 201020A: CrAO/ZTSH optical observations
- GRB 201020A: Swift-XRT refined Analysis
- GRB 201020A: Fermi GBM observation
- GRB 201020A: Swift-BAT refined analysis
- GRB 201020A: Assy optical observations
- GRB 201020A: Nanshan/NEXT optical observations
- Swift GRB 201020A: Global MASTER-Net observations report
- GRB 201020A: Enhanced Swift-XRT position
- GRB 201020A: MITSuME Akeno optical observation
- GRB 201020A: Swift detection of a burst with an optical counterpart.