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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').

8 results found.

  1. GRB 210901A: Swift/UVOT Upper Limits
  2. GRB 210901A: GROND observations
  3. GRB 210901A: Swift-XRT refined Analysis
  4. GRB 210901A: Swift-BAT refined analysis
  5. GRB 210901A: Enhanced Swift-XRT position
  6. GRB 210901A: LCO Optical Upper Limit
  7. Swift GRB 210901A: Global MASTER-Net observations report
  8. GRB 210901A: Swift detection of a burst

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