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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').

18 results found.

  1. GRB 090417B: Optical observation
  2. GRB 090417B: Swift/UVOT Upper Limits
  3. GRB 090417B Correction to the BAT refined analysis position
  4. GRB 090418: Erratum in GCN 9168
  5. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  6. VLA radio upper limit on GRB 090417B
  7. GRB 090417B: Gemini imaging
  8. GRB 090417B: Galaxy redshift
  9. GRB 090417B: Swift-XRT refined analysis
  10. GRB 090417B: Swift-BAT further refined analysis
  11. GRB 090417B: Subaru NIR Observations
  12. GRB 090417B: Liverpool Telescope observations
  13. GRB 090417B: MITSuME Okayama optical upper limits
  14. GRB090417B: Xinglong TNT optical upper limit
  15. GRB 090417B: optical observations
  16. GRB090417B: optical observations
  17. GRB 090417B: Swift-BAT refined analysis
  18. GRB 090417B: Swift detection of a burst

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