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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').

18311 results found.

  1. GRB041217: optical limit 30 min after GRB
  2. GRB041217: Optical Observations
  3. GRB041217: NIR and optical observations with REM
  4. GRB041217: P60 Optical Observations
  5. GRB041217: Infrared Observations
  6. GRB041217: The First GRB Located On-Board Swift
  7. GRB040916: Optical observations
  8. GRB040422: optical and NIR observations at the VLT
  9. GRB040223, improved XMM position
  10. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  11. SAX J0840.7+2248 Optical Observations

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