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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"

20 results found.

  1. GRB 251214B: Mondy optical upper limit
  2. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  3. GRB 251214B: UAFO optical upper limit
  4. GRB 251214B: VLT/X-shooter observations
  5. GRB 251214B: Swift-BAT refined analysis
  6. GRB 251214B: AbAO optical observations
  7. GRB 251214B: LCO detection of the optical counterpart
  8. GRB 251214B: Fermi GBM Observation
  9. GRB 251214B: GECAM-B observation of a long burst
  10. GRB 251214B: Swift-XRT refined Analysis
  11. GRB 251214B: Swift/UVOT Detection
  12. GRB 251214B: COLIBRÍ observations of the afterglow
  13. GRB 251214B: 1.3m DFOT optical detection
  14. GRB 251214B: Enhanced Swift-XRT position
  15. GRB 251214B: Xinglong-2.16m optical observation
  16. GRB 251214B : MASTER optical afterglow detection
  17. GRB 251214B: SVOM/C-GFT optical observations
  18. Swift GRB 251214B: Global MASTER-Net observations report
  19. GRB 251214B: Swift detection of a burst with an optical counterpart
  20. GRB 251214B: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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