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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').
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"

32107 results found.

  1. GRB 971024: KPNO Optical Observations
  2. GRB 971024: USNO Observations
  3. GRB 970925: BATSE Localization
  4. IRAS 18119-1342 and the possible new SGR
  5. Possible new SGR from US Naval Observatory
  6. GRB 970828: Palomar Observations
  7. GRB 970228: Keck/LRIS Optical Observations

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Download all Circulars as a .tar.gz archive:
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