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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').

10 results found.

  1. GRB 240418A: Swift-BAT refined analysis
  2. GRB240418A - Candidate afterglow from NIRES
  3. GRB 240418A: Swift/UVOT Upper Limits
  4. GRB 240418A: Swift-XRT refined Analysis
  5. GRB240418A: YAHPT Upper Limits
  6. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  7. GRB 240418A: NOT optical upper limits
  8. GRB 240418A: Enhanced Swift-XRT position
  9. GRB 240418A: AKO Upper Limit
  10. GRB 240418A: Swift detection of a burst

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