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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"

12 results found.

  1. GRB 220921A: ATCA detection of radio counterpart
  2. GRB 220921A: LCOGT Optical Observations
  3. GRB 220921A: further MeerLICHT observations
  4. GRB 220921A: ALMA detection
  5. GRB 220921A: DDOTI Detection of the Afterglow
  6. Konus-Wind detection of GRB 220921A
  7. GRB 220921A: Fermi GBM detection
  8. GRB 220921A: MeerLICHT afterglow observations
  9. GRB 220921A: Swift-XRT Observations
  10. GRB 220921A: MASTER OT inside Fermi-LAT error-box
  11. GRB 220921A: Fermi-LAT detection
  12. GRB 220921A: Tiled Swift observations

Advanced

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