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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').

9 results found.

  1. GRB 210509A: RATIR Optical and NIR Upper Limits
  2. GRB 210509A: Swift/UVOT Upper Limits
  3. GRB 210509A: Swift-XRT refined Analysis
  4. GRB 210509A: Swift-BAT refined analysis
  5. Swift GRB 210509A: Global MASTER-Net observations report
  6. GRB 210509A: Enhanced Swift-XRT position
  7. GRB 210509A: BOOTES-4/MET optical upper limit
  8. GRB 210509A: Swift-XRT observations
  9. GRB 210509A: Swift detection of a burst

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