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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"

28 results found.

  1. GRB 201029A: Swift-XRT refined Analysis
  2. GRB 130606A: P60 Observations
  3. GRB 080319B: Jet Break, Energetics, Supernova
  4. GRB 071021: possible high-z burst
  5. GRB 050904: Second Epoch of HST/NICMOS Observations
  6. GRB 060928: Swift observations
  7. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  8. GRB 060323: Tautenburg OT candidate retraction
  9. GRB050922B: Swift-BAT detection of a weak long burst
  10. GRB 050904 BAT refined analysis of complete data set
  11. GRB 050904: Subaru Optical Spectroscopy
  12. GRB 050904: Keck I-band Imaging
  13. GRB 050904: more VLT NIR observations
  14. GRB 050904: BOOTES early R-band observation
  15. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  16. GRB 050904: More SOAR
  17. GRB 050904: photometric redshift
  18. GRB 050904: Swift/UVOT observations
  19. GRB 050904: Afterglow Astrometry
  20. GRB 050904: NIR object inside the XRT error box
  21. GRB 050904: early Swift XRT analysis results
  22. GRB 050904: SOAR YJ and PROMPT Ic Observations
  23. GRB 050904: BAT refined analysis of partial data set
  24. GRB 050904: TAROT optical measurements
  25. GRB 050904: Environmental Constraints
  26. GRB 050904: Possible High-Redshift GRB
  27. GRB 050904: SOAR/PROMPT Observations
  28. GRB 050904: TAROT optical limits

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