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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').

13 results found.

  1. GRB 210402A: MASTER prompt and follow up optical observation
  2. GRB 210402A: Swift/UVOT Upper Limits
  3. GRB 210402A: Fermi GBM detection
  4. GRB 210402A: Further NOT optical observations
  5. GRB 210402A: Swift-BAT refined analysis
  6. GRB 210402A: NOT optical afterglow candidate
  7. GRB 210402A: BOOTES-network early optical upper limit
  8. GRB 210402A: LBT observations
  9. GRB 210402A: DDOTI Upper Limits
  10. GRB 210402A: Swift-XRT refined Analysis
  11. GRB 210402A: Montarrenti Observatory upper limit
  12. GRB 210402A: NOT optical upper limits
  13. GRB 210402A: Swift detection of a burst

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