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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"

24 results found.

  1. GRB 251103A: Optical afterglow detection by ZTF’s public survey
  2. GRB 251103A: WFST optical observations
  3. GRB 251103A: OHP/T193 optical observations
  4. GRB 251103A: Xinglong 2.16m optical detection
  5. GRB 251103A: Insight-HXMT detection
  6. GRB 251103A: KAIT optical observations
  7. GRB 251103A: Swift/BAT-GUANO arcminute localization of a burst
  8. Fermi GRB 251103A: Global MASTER-Net observations report
  9. GRB 251103A: J-band detection with WINTER
  10. GRB 251103A: Kilonova-Catcher optical afterglow detection
  11. GRB 251103A: Swift/UVOT Detection
  12. GRB 251103A: Fermi GBM Observation
  13. GRB 251103A: SVOM/GRM observation
  14. GRB 251103A: Swift-XRT afterglow detection
  15. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  16. GRB 251103A: LCO optical observation
  17. GRB 251103A: GOTO optical afterglow detection
  18. GRB 251103A: NOT spectroscopic redshift z = 0.76
  19. GRB 251103A: BOOTES-2/TELMA optical afterglow
  20. GRB 251103A: LCO optical afterglow detection
  21. GRB 251103A: NOT optical afterglow candidate (duplicate submission)
  22. GRB 251103A: Fermi GBM Final Localization
  23. GRB 251103A: NOT optical afterglow candidate
  24. GRB 251103A: SVOM detection of a bright burst

Advanced

Download all Circulars as a .tar.gz archive:
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