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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').

15 results found.

  1. GRB 220403B: GRANDMA observations
  2. GRB 220403B: Swift/UVOT Detection
  3. GRB 220403B: 1.3m DFOT Optical upper limit
  4. GRB 220403B: Mondy optical upper limit
  5. GRB 220403B: 1.5m OSN optical observation
  6. GRB 220403B: Kitab optical observations
  7. GRB 220403B: Swift-BAT refined analysis
  8. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  9. GRB 220403B: Fermi GBM detection
  10. GRB 220403B: Swift-XRT refined Analysis
  11. GRB 220403B: LBT observations
  12. Swift GRB 220403B: Global MASTER-Net observations report
  13. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  14. GRB 220403B: optical detection by D50
  15. GRB 220403B: Swift detection of a burst with an optical counterpart

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