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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"

11 results found.

  1. EP 250108A: Upper limits from Fermi-GBM Observations
  2. EP 250108A: Late-time optical observation by LCO
  3. EP250108a / AT2025kg: GMG Optical Observations
  4. GRB 250108A: Swift/XRT afterglow fading
  5. EP-WXT trigger EP250108a：Xinglong optical follow-up observations
  6. GRB 250108A: Swift/UVOT Upper Limits
  7. GRB 250108A: NOT optical upper limit
  8. GRB 250108A: Swift-XRT afterglow detection
  9. GRB 250108A:SVOM/VT optical candidate
  10. GRB 250108A: Swift ToO observations
  11. GRB 250108A: SVOM detection of a soft long burst

Advanced

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