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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').

15 results found.

  1. GRB 200228B: continued optical observations
  2. GRB 200228B: Mondy, TSHAO, AbAO and CrAO optical observations, afterglow candidate
  3. GRB 200228B: LCO Optical Upper Limit
  4. GRB 200228B: Swift-BAT refined analysis
  5. GRB 200228B: RATIR Optical Observations
  6. GRB 200228B: Liverpool Telescope imaging
  7. GRB 200228B: Swift-XRT refined Analysis
  8. Swift GRB 200228B: Global MASTER-Net observations report
  9. GRB 200228B: Swift/UVOT Upper Limits
  10. GRB 200228B: RATIR Optical Observations
  11. GRB 200228B: Fermi GBM observation
  12. GRB 200228B: KAIT Optical Upper Limit
  13. GRB 200228B: Enhanced Swift-XRT position
  14. GRB 200228B: Swift detection of a burst
  15. GRB 200228B: Fermi GBM Final Real-time Localization

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