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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

25 results found.

  1. GRB 241030B: TESS detection of optical counterpart
  2. GRB 241030B: Swift-XRT refined Analysis
  3. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  4. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  5. GRB 241030B: Montarrenti Observatory optical upper limit
  6. GRB 241030B : GIT optical upper limits
  7. GRB 241030B: LCOGT Optical Upper Limits
  8. GRB 241030B: Swift-BAT refined analysis
  9. GRB 241030B: Swift/UVOT Detection
  10. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  11. GRB 241030B: SVOM/GRM observation
  12. GRB 241030B : MITSuME Akeno optical upper limits
  13. GRB 241030B: SVOM/VT optical afterglow observations
  14. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  15. GRB 241030B: BTA observations
  16. GRB 241030B: Enhanced Swift-XRT position
  17. GRB 241030B: optical observations from the INAF Asiago Observatory
  18. GRB241030B: GRANDMA/TAROT Upper Limit
  19. GRB 241030B: SAO RAS optical observations
  20. GRB 241030B: AKO Optical Afterglow Detection
  21. GRB 241030B: Nanshan/HMT optical afterglow detection
  22. GRB 241030B: SVOM/ECLAIRs detection of a burst
  23. GRB 241030B: Prompt enhanced Swift-XRT position
  24. GRB 241030B: Swift detection of a burst
  25. GRB 241030B: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive:
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