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"14 results found.
- GRB 251003A: LAST optical observations
- GRB 251003A: Swift/UVOT Upper Limits
- GRB 251003A: Swift-XRT refined Analysis
- GRB 251003A: COLIBRÍ photometric redshift
- GRB 251003A: GOTO detection of the optical counterpart
- GRB 251003A: Enhanced Swift-XRT position
- GRB 251003A: GTC/OSIRIS+ spectroscopic redshift z = 4.412
- GRB 251003A: Kilonova-Catcher optical afterglow detection
- GRB 251003A: LCOGT Optical Detection
- GRB 251003A: COLIBRÍ optical detection of the fading afterglow
- GRB 251003A: 1.5m OSN afterglow candidate
- GRB 251003A: Prompt enhanced Swift-XRT position
- GRB 251003A: Swift detection of a burst
- GRB 251003A: Fermi GBM Final Real-time Localization