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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 210723A: Swift/UVOT Upper Limits
  2. GRB 210723A: CALET Gamma-Ray Burst Monitor detection
  3. GRB 210723A: Fermi GBM Observation
  4. GRB 210723A: Swift-BAT refined analysis
  5. GRB 210723A: Swift-XRT refined Analysis
  6. Swift GRB 210723A: Global MASTER-Net observations report
  7. GRB 210723A: Prompt enhanced Swift-XRT position
  8. GRB 210723A: Swift detection of a burst

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