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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. GRB 150817A: AAO optical observations
  2. GRB 150817A: LCOGT observations
  3. GRB 150817A: Continued RATIR Optical Observations - Afterglow Confirmation
  4. GRB 150817A: P60 Observations
  5. GRB 150817A: Swift/UVOT Upper Limits
  6. GRB 150817A: Fermi GBM observation
  7. GRB 150817A: Swift-BAT refined analysis
  8. GRB 150817A: Swift-XRT refined Analysis
  9. GRB 150817A: Enhanced Swift-XRT position
  10. GRB 150817A: Continued RATIR Observations, Revised Candidate
  11. GRB 150817A: RATIR Optical Afterglow Candidate
  12. GRB 150817A: Swift detection of a burst

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