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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').

12 results found.

  1. GRB100305A: Optical upper limits at IAO
  2. GRB 100305A: Super-LOTIS early observations
  3. GRB 100305A, Swift-BAT refined analysis
  4. GRB 100305A: Gemini z'-band observation
  5. GRB 100305A: Swift/UVOT Upper Limits
  6. GRB 100305A: Swift-XRT refined analysis
  7. GRB 100305A Optical Observations
  8. GRB 100305A: Enhanced Swift-XRT position
  9. GRB 100305A: Gemini-N OT candidate
  10. GRB 100305A: PAIRITEL NIR Upper Limits
  11. GRB 100305A: P60 Observations
  12. GRB 100305A: Swift detection of a burst

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