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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

5 results found.

  1. GRB 090915: GROND upper limits
  2. GRB 090915: SARA detection of afterglow candidate
  3. GRB 090915: Swift/UVOT detection of an optical afterglow candidate
  4. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  5. GRB 090915 Swift-BAT detection of a burst in ground analysis

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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