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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 210419C: Swift/UVOT Upper Limits
  2. GRB 210419C: MITSuME Akeno optical upper limits
  3. GRB 210419C: Swift-BAT refined analysis
  4. GRB 210419C: RATIR Optical and NIR Upper Limits
  5. GRB 210419C: Montarrenti Observatory Upper Limit
  6. GRB 210419C: KAIT Optical Upper Limit
  7. GRB 210419C: Enhanced Swift-XRT position
  8. GRB 210419C: Swift detection of a burst

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