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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"

23 results found.

  1. GRB 241105A: JWST photometric observations of the host galaxy
  2. GRB 241105A: ATCA radio detection
  3. GRB 241105A: ATCA Radio Upper Limits
  4. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  5. GRB 241105A: EP-FXT follow-up observations
  6. GRB 241105A: SVOM/GRM observation
  7. GRB 241105a: PRIME near-infrared upper limits
  8. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  9. GRB241105A: Gemini-South Optical Afterglow Detection
  10. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  11. GRB 241105A: Swift/UVOT Detection
  12. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  13. GRB 241105A: BOOTES-7 optical detection
  14. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  15. Konus-Wind detection of GRB 241105A (short with extended emission)
  16. GRB 241105A: SVOM/VT optical afterglow observations
  17. GRB 241105A: Swift-XRT afterglow detection
  18. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  19. GRB 241105A: Swift ToO observations
  20. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  21. GRB 241105A: GOTO tentative optical counterpart candidate
  22. Fermi GRB 241105A: Global MASTER-Net observations report
  23. GRB 241105A: Fermi GBM Final Real-time Localization

Advanced

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