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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"

26 results found.

  1. GRB 251002A: LAST optical observations
  2. GRB 251002A: Mondy/AZT-33IK optical observations
  3. GRB 251002A: Insight-HXMT detection
  4. GRB 251002A: Insight-HXMT detection
  5. GRB 251002A: NIR observations with WINTER
  6. GRB 251002A: Swift/UVOT detection
  7. GRB 251002A: Fermi GBM Observation
  8. GRB 251002A: GOTO detection of optical counterpart
  9. GRB 251002A: AKO Early Optical Afterglow Detection
  10. GRB 251002A: Swift-XRT afterglow detection
  11. GRB 251002A: Kilonova-Catcher optical afterglow detection
  12. GRB 251002A: AbAO optical observations
  13. GRB 251002A: SVOM/COLIBRÍ (FM-GFT) optical observations
  14. GRB 251002A: J band observations by SYSU 80cm infrared telescope
  15. GRB 251002A: OHP/T193 MISTRAL optical afterglow detection
  16. GRB 251002A: VLT/X-shooter spectroscopic redshift z = 2.178
  17. GRB 251002A: EP-FXT counterpart detection
  18. Fermi/SVOM GRB 251002A : MASTER OT earlier detection in 2 polarization filters
  19. GRB 251002A: BOOTES-6 early optical detection
  20. GRB 251002A: SAO RAS optical observations
  21. GRB 251002A: ULL-ASTRO-MASTER early detection of the optical afterglow with the LCO 40-cm telescope at Sutherland Observatory
  22. GRB 251002A: FRAM-ORM afterglow detection
  23. GRB 251002A: LCO optical observation
  24. GRB 251002A: SVOM/VT optical observation
  25. GRB 251002A: SVOM detection of a burst
  26. Fermi GRB 251002A: Global MASTER-Net observations report

Advanced

Download all Circulars as a .tar.gz archive:
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