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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').

11 results found.

  1. GRB 091221 : IRSF NIR upper limit
  2. GRB 091221: Skynet/PROMPT Detections
  3. GRB 091221: Fermi GBM Observation
  4. GRB 091221 Swift-BAT refined analysis
  5. GRB 091221: Swift/UVOT refined analysis
  6. GRB 091221: Swift-XRT refined analysis
  7. GRB 091221: Enhanced Swift-XRT position
  8. GRB 091221, GROND observations
  9. GRB 091221: UVOT Confirmation of an Optical Afterglow
  10. GRB 091221: ROTSE-III Detection of Optical Counterpart
  11. GRB 091221: Swift detection of a burst

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