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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').

11 results found.

  1. GRB 230906A: optical counterpart
  2. GRB 230906A: Chandra detection of the X-ray afterglow
  3. GRB 230906A: BlackGEM upper limits
  4. GRB 230906A: AstroSat CZTI detection
  5. GRB 230906A: Swift/UVOT Upper Limits
  6. GRB 230906A: Swift-XRT observations
  7. Konus-Wind detection of GRB 230906A (short)
  8. IPN triangulation of GRB 230906A (short)
  9. GRB 230906A: Swift ToO observations
  10. Fermi GRB 230906A: Global MASTER-Net observations report
  11. GRB 230906A: Fermi GBM Final Localizationn

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